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1. Erratum: 'The NANOGrav 15 yr Data Set: Search for Signals from New Physics' (2023, ApJL 951 L11)

Author

Adeela Afzal, Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Paul T. Baker, Bence Bécsy, Jose Juan Blanco-Pillado, Laura Blecha, Kimberly K. Boddy, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, Robin Case, Maria Charisi, Shami Chatterjee, Katerina Chatziioannou, Belinda D. Cheeseboro, Siyuan Chen, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Curt J. Cutler, Megan E. DeCesar, Dallas DeGan, Paul B. Demorest, Heling Deng, Timothy Dolch, Brendan Drachler, Richard von Eckardstein, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nate Garver-Daniels, Peter A. Gentile, Kyle A. Gersbach, Joseph Glaser, Deborah C. Good, Lydia Guertin, Kayhan Gültekin, Jeffrey S. Hazboun, Sophie Hourihane, Kristina Islo, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Matthew Kerr, Joey S. Key, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Vincent S. H. Lee, Natalia Lewandowska, Rafael R. Lino dos Santos, Tyson B. Littenberg, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Natasha McMann, Bradley W. Meyers, Patrick M. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Jonathan Nay, Priyamvada Natarajan, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Benetge B. P. Perera, Polina Petrov, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Shashwat C. Sardesai, Ann Schmiedekamp, Carl Schmiedekamp, Kai Schmitz, Tobias Schröder, Levi Schult, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Peter Stratmann, Jerry P. Sun, Abhimanyu Susobhanan, Joseph K. Swiggum, Jacob Taylor, Stephen R. Taylor, Tanner Trickle, Jacob E. Turner, Caner Unal, Michele Vallisneri, Sonali Verma, Sarah J. Vigeland, Haley M. Wahl, Qiaohong Wang, Caitlin A. Witt, David Wright, Olivia Young, Kathryn M. Zurek, and The NANOGrav Collaboration

Subjects
Astrophysics, QB460-466
Published
2024
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2. The NANOGrav 15 yr Data Set: Search for Transverse Polarization Modes in the Gravitational-wave Background

Author

Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Jeremy Baier, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, Robin Case, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. DeCesar, Dallas DeGan, Paul B. Demorest, Timothy Dolch, Brendan Drachler, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nate Garver-Daniels, Peter A. Gentile, Joseph Glaser, Deborah C. Good, Kayhan Gültekin, Jeffrey S. Hazboun, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Matthew Kerr, Joey S. Key, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Natasha McMann, Bradley W. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Priyamvada Natarajan, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Benetge B. P. Perera, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Alexander Saffer, Shashwat C. Sardesai, Ann Schmiedekamp, Carl Schmiedekamp, Kai Schmitz, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Jerry P. Sun, Abhimanyu Susobhanan, Joseph K. Swiggum, Jacob A. Taylor, Stephen R. Taylor, Jacob E. Turner, Caner Unal, Michele Vallisneri, Sarah J. Vigeland, Haley M. Wahl, Caitlin A. Witt, Olivia Young, and The NANOGrav Collaboration

Subjects
Gravitational waves, Pulsars, Scalar-tensor-vector gravity, Astrophysics, QB460-466
Abstract

Recently we found compelling evidence for a gravitational-wave background with Hellings and Downs (HD) correlations in our 15 yr data set. These correlations describe gravitational waves as predicted by general relativity, which has two transverse polarization modes. However, more general metric theories of gravity can have additional polarization modes, which produce different interpulsar correlations. In this work, we search the NANOGrav 15 yr data set for evidence of a gravitational-wave background with quadrupolar HD and scalar-transverse (ST) correlations. We find that HD correlations are the best fit to the data and no significant evidence in favor of ST correlations. While Bayes factors show strong evidence for a correlated signal, the data does not strongly prefer either correlation signature, with Bayes factors ∼2 when comparing HD to ST correlations, and ∼1 for HD plus ST correlations to HD correlations alone. However, when modeled alongside HD correlations, the amplitude and spectral index posteriors for ST correlations are uninformative, with the HD process accounting for the vast majority of the total signal. Using the optimal statistic, a frequentist technique that focuses on the pulsar-pair cross-correlations, we find median signal-to-noise ratios of 5.0 for HD and 4.6 for ST correlations when fit for separately, and median signal-to-noise ratios of 3.5 for HD and 3.0 for ST correlations when fit for simultaneously. While the signal-to-noise ratios for each of the correlations are comparable, the estimated amplitude and spectral index for HD are a significantly better fit to the total signal, in agreement with our Bayesian analysis.

Published
2024
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3. A Statistical Analysis of Crab Pulsar Giant Pulse Rates

Author

Graham M. Doskoch, Andrea Basuroski, Kriisa Halley, Avinash Sookram, Iliomar Rodriguez-Ramos, Valmik Nahata, Zahi Rahman, Maureen Zhang, Ashish Uhlmann, Abby Lynch, Natalia Lewandowska, Nohely Miranda, Ann Schmiedekamp, Carl Schmiedekamp, Maura A. McLaughlin, Daniel E. Reichart, Joshua B. Haislip, Vladimir V. Kouprianov, Steve White, Frank Ghigo, and Sue Ann Heatherly

Subjects
Pulsars, Neutron stars, Interstellar scintillation, Astrophysics, QB460-466
Abstract

A small number of pulsars are known to emit giant pulses (GPs), single pulses much brighter than average. Among these is PSR J0534+2200, also known as the Crab pulsar, a young pulsar with high GP rates. Long-term monitoring of the Crab pulsar presents an excellent opportunity to perform statistical studies of its GPs and the processes affecting them, potentially providing insight into the behavior of other neutron stars that emit bright single pulses. Here, we present an analysis of a set of 24,985 Crab GPs obtained from 88 hr of daily observations at a center frequency of 1.55 GHz by the 20 m telescope at the Green Bank Observatory, spread over 461 days. We study the effects of refractive scintillation at higher frequencies than previous studies and compare methods of correcting for this effect. We also search for deterministic patterns seen in other single-pulse sources, possible periodicities seen in several rotating radio transients and fast radio bursts, and clustering of GPs like that seen in the repeating fast radio burst FRB 121102.

Published
2024
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4. The NANOGrav 12.5 yr Data Set: A Computationally Efficient Eccentric Binary Search Pipeline and Constraints on an Eccentric Supermassive Binary Candidate in 3C 66B

Author

Gabriella Agazie, Zaven Arzoumanian, Paul T. Baker, Bence Bécsy, Laura Blecha, Harsha Blumer, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Belinda D. Cheeseboro, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Megan E. DeCesar, Paul B. Demorest, Lankeswar Dey, Timothy Dolch, Justin A. Ellis, Robert D. Ferdman, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nate Garver-Daniels, Peter A. Gentile, Joseph Glaser, Deborah C. Good, Achamveedu Gopakumar, Kayhan Gültekin, Jeffrey S. Hazboun, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Joey S. Key, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Patrick M. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Shashwat C. Sardesai, Kai Schmitz, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Sophia V. Sosa Fiscella, Renée Spiewak, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Abhimanyu Susobhanan, Joseph K. Swiggum, Stephen R. Taylor, Jacob E. Turner, Caner Unal, Michele Vallisneri, Sarah J. Vigeland, Caitlin A. Witt, Olivia Young, and The NANOGrav Collaboration

Subjects
Gravitational waves, Millisecond pulsars, Supermassive black holes, Astrophysics, QB460-466
Abstract

The radio galaxy 3C 66B has been hypothesized to host a supermassive black hole binary (SMBHB) at its center based on electromagnetic observations. Its apparent 1.05 yr period and low redshift (∼0.02) make it an interesting testbed to search for low-frequency gravitational waves (GWs) using pulsar timing array (PTA) experiments. This source has been subjected to multiple searches for continuous GWs from a circular SMBHB, resulting in progressively more stringent constraints on its GW amplitude and chirp mass. In this paper, we develop a pipeline for performing Bayesian targeted searches for eccentric SMBHBs in PTA data sets, and test its efficacy by applying it to simulated data sets with varying injected signal strengths. We also search for a realistic eccentric SMBHB source in 3C 66B using the NANOGrav 12.5 yr data set employing PTA signal models containing Earth term-only as well as Earth+pulsar term contributions using this pipeline. Due to limitations in our PTA signal model, we get meaningful results only when the initial eccentricity e _0 < 0.5 and the symmetric mass ratio η > 0.1. We find no evidence for an eccentric SMBHB signal in our data, and therefore place 95% upper limits on the PTA signal amplitude of 88.1 ± 3.7 ns for the Earth term-only and 81.74 ± 0.86 ns for the Earth+pulsar term searches for e _0 < 0.5 and η > 0.1. Similar 95% upper limits on the chirp mass are (1.98 ± 0.05) × 10 ^9 and (1.81 ± 0.01) × 10 ^9 M _☉ . These upper limits, while less stringent than those calculated from a circular binary search in the NANOGrav 12.5 yr data set, are consistent with the SMBHB model of 3C 66B developed from electromagnetic observations.

Published
2024
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5. The NANOGrav 12.5 yr Data Set: Search for Gravitational Wave Memory

Author

Gabriella Agazie, Zaven Arzoumanian, Paul T. Baker, Bence Bécsy, Laura Blecha, Harsha Blumer, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, Robin Case, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Megan E. DeCesar, Dallas DeGan, Paul B. Demorest, Timothy Dolch, Brendan Drachler, Justin A. Ellis, Robert D. Ferdman, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nate Garver-Daniels, Peter A. Gentile, Joseph Glaser, Deborah C. Good, Kayhan Gültekin, Jeffrey S. Hazboun, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Joey S. Key, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Patrick M. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Nihan S. Pol, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Shashwat C. Sardesai, Kai Schmitz, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Sophia V. Sosa Fiscella, Renée Spiewak, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Jerry P. Sun, Joseph K. Swiggum, Jacob Taylor, Stephen R. Taylor, Jacob E. Turner, Caner Unal, Michele Vallisneri, Sarah J. Vigeland, Haley M. Wahl, Caitlin A. Witt, Olivia Young, and The NANOGrav Collaboration

Subjects
Gravitational waves, Gravitational wave astronomy, Astrophysics, QB460-466
Abstract

We present the results of a Bayesian search for gravitational wave (GW) memory in the NANOGrav 12.5 yr data set. We find no convincing evidence for any gravitational wave memory signals in this data set. We find a Bayes factor of 2.8 in favor of a model that includes a memory signal and common spatially uncorrelated red noise (CURN) compared to a model including only a CURN. However, further investigation shows that a disproportionate amount of support for the memory signal comes from three dubious pulsars. Using a more flexible red-noise model in these pulsars reduces the Bayes factor to 1.3. Having found no compelling evidence, we go on to place upper limits on the strain amplitude of GW memory events as a function of sky location and event epoch. These upper limits are computed using a signal model that assumes the existence of a common, spatially uncorrelated red noise in addition to a GW memory signal. The median strain upper limit as a function of sky position is approximately 3.3 × 10 ^−14 . We also find that there are some differences in the upper limits as a function of sky position centered around PSR J0613−0200. This suggests that this pulsar has some excess noise that can be confounded with GW memory. Finally, the upper limits as a function of burst epoch continue to improve at later epochs. This improvement is attributable to the continued growth of the pulsar timing array.

Published
2024
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6. The NANOGrav 15 yr Data Set: Search for Anisotropy in the Gravitational-wave Background

Author

Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. DeCesar, Paul B. Demorest, Timothy Dolch, Brendan Drachler, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Emiko Gardiner, Nate Garver-Daniels, Peter A. Gentile, Joseph Glaser, Deborah C. Good, Kayhan Gültekin, Jeffrey S. Hazboun, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Matthew Kerr, Joey S. Key, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Natasha McMann, Bradley W. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Benetge B. P. Perera, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Shashwat C. Sardesai, Ann Schmiedekamp, Carl Schmiedekamp, Kai Schmitz, Levi Schult, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Abhimanyu Susobhanan, Joseph K. Swiggum, Stephen R. Taylor, Jacob E. Turner, Caner Unal, Michele Vallisneri, Sarah J. Vigeland, Haley M. Wahl, Caitlin A. Witt, and Olivia Young

Subjects
Gravitational waves, Gravitational wave astronomy, Supermassive black holes, Pulsars, Astrophysics, QB460-466
Abstract

The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has reported evidence for the presence of an isotropic nanohertz gravitational-wave background (GWB) in its 15 yr data set. However, if the GWB is produced by a population of inspiraling supermassive black hole binary (SMBHB) systems, then the background is predicted to be anisotropic, depending on the distribution of these systems in the local Universe and the statistical properties of the SMBHB population. In this work, we search for anisotropy in the GWB using multiple methods and bases to describe the distribution of the GWB power on the sky. We do not find significant evidence of anisotropy. By modeling the angular power distribution as a sum over spherical harmonics (where the coefficients are not bound to always generate positive power everywhere), we find that the Bayesian 95% upper limit on the level of dipole anisotropy is ( C _l _=1 / C _l _=0 ) < 27%. This is similar to the upper limit derived under the constraint of positive power everywhere, indicating that the dipole may be close to the data-informed regime. By contrast, the constraints on anisotropy at higher spherical-harmonic multipoles are strongly prior dominated. We also derive conservative estimates on the anisotropy expected from a random distribution of SMBHB systems using astrophysical simulations conditioned on the isotropic GWB inferred in the 15 yr data set and show that this data set has sufficient sensitivity to probe a large fraction of the predicted level of anisotropy. We end by highlighting the opportunities and challenges in searching for anisotropy in pulsar timing array data.

Published
2023
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7. The NANOGrav 15 yr Data Set: Constraints on Supermassive Black Hole Binaries from the Gravitational-wave Background

Author

Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Paul T. Baker, Bence Bécsy, Laura Blecha, Alexander Bonilla, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, Robin Case, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Katerina Chatziioannou, Belinda D. Cheeseboro, Siyuan Chen, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Curt J. Cutler, Daniel J. D’Orazio, Megan E. DeCesar, Dallas DeGan, Paul B. Demorest, Heling Deng, Timothy Dolch, Brendan Drachler, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Emiko Gardiner, Nate Garver-Daniels, Peter A. Gentile, Kyle A. Gersbach, Joseph Glaser, Deborah C. Good, Kayhan Gültekin, Jeffrey S. Hazboun, Sophie Hourihane, Kristina Islo, Ross J. Jennings, Aaron Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Matthew Kerr, Joey S. Key, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Tyson B. Littenberg, Tingting Liu, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Natasha McMann, Bradley W. Meyers, Patrick M. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Priyamvada Natarajan, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Benetge B. P. Perera, Polina Petrov, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Jessie C. Runnoe, Shashwat C. Sardesai, Ann Schmiedekamp, Carl Schmiedekamp, Kai Schmitz, Levi Schult, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Jerry P. Sun, Abhimanyu Susobhanan, Joseph K. Swiggum, Jacob Taylor, Stephen R. Taylor, Jacob E. Turner, Caner Unal, Michele Vallisneri, Sarah J. Vigeland, Jeremy M. Wachter, Haley M. Wahl, Qiaohong Wang, Caitlin A. Witt, David Wright, Olivia Young, and The NANOGrav Collaboration

Subjects
Gravitational waves, Supermassive black holes, Galaxy evolution, Astrophysics, QB460-466
Abstract

The NANOGrav 15 yr data set shows evidence for the presence of a low-frequency gravitational-wave background (GWB). While many physical processes can source such low-frequency gravitational waves, here we analyze the signal as coming from a population of supermassive black hole (SMBH) binaries distributed throughout the Universe. We show that astrophysically motivated models of SMBH binary populations are able to reproduce both the amplitude and shape of the observed low-frequency gravitational-wave spectrum. While multiple model variations are able to reproduce the GWB spectrum at our current measurement precision, our results highlight the importance of accurately modeling binary evolution for producing realistic GWB spectra. Additionally, while reasonable parameters are able to reproduce the 15 yr observations, the implied GWB amplitude necessitates either a large number of parameters to be at the edges of expected values or a small number of parameters to be notably different from standard expectations. While we are not yet able to definitively establish the origin of the inferred GWB signal, the consistency of the signal with astrophysical expectations offers a tantalizing prospect for confirming that SMBH binaries are able to form, reach subparsec separations, and eventually coalesce. As the significance grows over time, higher-order features of the GWB spectrum will definitively determine the nature of the GWB and allow for novel constraints on SMBH populations.

Published
2023
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8. The NANOGrav 15 yr Data Set: Bayesian Limits on Gravitational Waves from Individual Supermassive Black Hole Binaries

Author

Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Robin Case, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. DeCesar, Paul B. Demorest, Matthew C. Digman, Timothy Dolch, Brendan Drachler, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nate Garver-Daniels, Peter A. Gentile, Joseph Glaser, Deborah C. Good, Kayhan Gültekin, Jeffrey S. Hazboun, Sophie Hourihane, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Matthew Kerr, Joey S. Key, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Natasha McMann, Bradley W. Meyers, Patrick M. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Benetge B. P. Perera, Polina Petrov, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Shashwat C. Sardesai, Ann Schmiedekamp, Carl Schmiedekamp, Kai Schmitz, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Abhimanyu Susobhanan, Joseph K. Swiggum, Jacob Taylor, Stephen R. Taylor, Jacob E. Turner, Caner Unal, Michele Vallisneri, Rutger van Haasteren, Sarah J. Vigeland, Haley M. Wahl, Caitlin A. Witt, Olivia Young, and The NANOGrav Collaboration

Subjects
Gravitational wave astronomy, Astrophysics, QB460-466
Abstract

Evidence for a low-frequency stochastic gravitational-wave background has recently been reported based on analyses of pulsar timing array data. The most likely source of such a background is a population of supermassive black hole binaries, the loudest of which may be individually detected in these data sets. Here we present the search for individual supermassive black hole binaries in the NANOGrav 15 yr data set. We introduce several new techniques, which enhance the efficiency and modeling accuracy of the analysis. The search uncovered weak evidence for two candidate signals, one with a gravitational-wave frequency of ∼4 nHz, and another at ∼170 nHz. The significance of the low-frequency candidate was greatly diminished when Hellings–Downs correlations were included in the background model. The high-frequency candidate was discounted due to the lack of a plausible host galaxy, the unlikely astrophysical prior odds of finding such a source, and since most of its support comes from a single pulsar with a commensurate binary period. Finding no compelling evidence for signals from individual binary systems, we place upper limits on the strain amplitude of gravitational waves emitted by such systems. At our most sensitive frequency of 6 nHz, we place a sky-averaged 95% upper limit of 8 × 10 ^−15 on the strain amplitude. We also calculate an exclusion volume and a corresponding effective radius, within which we can rule out the presence of black hole binaries emitting at a given frequency.

Published
2023
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9. The NANOGrav 12.5 yr Data Set: Bayesian Limits on Gravitational Waves from Individual Supermassive Black Hole Binaries

Author

Zaven Arzoumanian, Paul T. Baker, Laura Blecha, Harsha Blumer, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Bence Bécsy, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Siyuan Chen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Megan E. DeCesar, Paul B. Demorest, Timothy Dolch, Brendan Drachler, Justin A. Ellis, E. C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nathan Garver-Daniels, Peter A. Gentile, Joseph Glaser, Deborah C. Good, Kayhan Gültekin, Jeffrey S. Hazboun, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Joey Shapiro Key, Nima Laal, Michael T. Lam, William G Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Dustin R. Madison, Alexander McEwen, Maura A. McLaughlin, Chiara M. F. Mingarelli, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Nihan S. Pol, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena Siwek, Renée Spiewak, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Joseph K. Swiggum, Jessica Sydnor, Stephen R. Taylor, Jacob E. Turner, Michele Vallisneri, Sarah J. Vigeland, Haley M. Wahl, Gregory Walsh, Caitlin A. Witt, Olivia Young, and The NANOGrav Collaboration

Subjects
Gravitational waves, Astronomy data analysis, Millisecond pulsars, Supermassive black holes, Astrophysics, QB460-466
Abstract

Pulsar timing array collaborations, such as the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), are seeking to detect nanohertz gravitational waves emitted by supermassive black hole binaries formed in the aftermath of galaxy mergers. We have searched for continuous waves from individual circular supermassive black hole binaries using NANOGrav’s recent 12.5 yr data set. We created new methods to accurately model the uncertainties on pulsar distances in our analysis, and we implemented new techniques to account for a common red-noise process in pulsar timing array data sets while searching for deterministic gravitational wave signals, including continuous waves. As we found no evidence for continuous waves in our data, we placed 95% upper limits on the strain amplitude of continuous waves emitted by these sources. At our most sensitive frequency of 7.65 nHz, we placed a sky-averaged limit of h _0 < (6.82 ± 0.35) × 10 ^−15 , and h _0 < (2.66 ± 0.15) × 10 ^−15 in our most sensitive sky location. Finally, we placed a multimessenger limit of ${ \mathcal M }\lt (1.41\pm 0.02)\times {10}^{9}\,{M}_{\odot }$ on the chirp mass of the supermassive black hole binary candidate 3C 66B.

Published
2023
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10. The NANOGrav 15 yr Data Set: Evidence for a Gravitational-wave Background

Author

Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, Robin Case, Maria Charisi, Shami Chatterjee, Katerina Chatziioannou, Belinda D. Cheeseboro, Siyuan Chen, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Curt J. Cutler, Megan E. DeCesar, Dallas DeGan, Paul B. Demorest, Heling Deng, Timothy Dolch, Brendan Drachler, Justin A. Ellis, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nate Garver-Daniels, Peter A. Gentile, Kyle A. Gersbach, Joseph Glaser, Deborah C. Good, Kayhan Gültekin, Jeffrey S. Hazboun, Sophie Hourihane, Kristina Islo, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Matthew Kerr, Joey S. Key, Tonia C. Klein, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Tyson B. Littenberg, Tingting Liu, Andrea Lommen, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Margaret A. Mattson, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Natasha McMann, Bradley W. Meyers, Patrick M. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Priyamvada Natarajan, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Benetge B. P. Perera, Polina Petrov, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Shashwat C. Sardesai, Ann Schmiedekamp, Carl Schmiedekamp, Kai Schmitz, Levi Schult, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Jerry P. Sun, Abhimanyu Susobhanan, Joseph K. Swiggum, Jacob Taylor, Stephen R. Taylor, Jacob E. Turner, Caner Unal, Michele Vallisneri, Rutger van Haasteren, Sarah J. Vigeland, Haley M. Wahl, Qiaohong Wang, Caitlin A. Witt, Olivia Young, and The NANOGrav Collaboration

Subjects
Gravitational waves, Gravitational wave astronomy, Millisecond pulsars, Radio pulsars, Supermassive black holes, Astrophysics, QB460-466
Abstract

We report multiple lines of evidence for a stochastic signal that is correlated among 67 pulsars from the 15 yr pulsar timing data set collected by the North American Nanohertz Observatory for Gravitational Waves. The correlations follow the Hellings–Downs pattern expected for a stochastic gravitational-wave background. The presence of such a gravitational-wave background with a power-law spectrum is favored over a model with only independent pulsar noises with a Bayes factor in excess of 10 ^14 , and this same model is favored over an uncorrelated common power-law spectrum model with Bayes factors of 200–1000, depending on spectral modeling choices. We have built a statistical background distribution for the latter Bayes factors using a method that removes interpulsar correlations from our data set, finding p = 10 ^−3 (≈3 σ ) for the observed Bayes factors in the null no-correlation scenario. A frequentist test statistic built directly as a weighted sum of interpulsar correlations yields p = 5 × 10 ^−5 to 1.9 × 10 ^−4 (≈3.5 σ –4 σ ). Assuming a fiducial f ^−2/3 characteristic strain spectrum, as appropriate for an ensemble of binary supermassive black hole inspirals, the strain amplitude is ${2.4}_{-0.6}^{+0.7}\times {10}^{-15}$ (median + 90% credible interval) at a reference frequency of 1 yr ^−1 . The inferred gravitational-wave background amplitude and spectrum are consistent with astrophysical expectations for a signal from a population of supermassive black hole binaries, although more exotic cosmological and astrophysical sources cannot be excluded. The observation of Hellings–Downs correlations points to the gravitational-wave origin of this signal.

Published
2023
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11. The NANOGrav 15 yr Data Set: Observations and Timing of 68 Millisecond Pulsars

Author

Gabriella Agazie, Md Faisal Alam, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Paul T. Baker, Laura Blecha, Victoria Bonidie, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Bence Bécsy, Christopher Chapman, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. DeCesar, Paul B. Demorest, Timothy Dolch, Brendan Drachler, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nate Garver-Daniels, Peter A. Gentile, Joseph Glaser, Deborah C. Good, Kayhan Gültekin, Jeffrey S. Hazboun, Ross J. Jennings, Cody Jessup, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Matthew Kerr, Joey S. Key, Anastasia Kuske, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Ye Lin, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Kaleb Maraccini, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Natasha McMann, Bradley W. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Elisa Panciu, Timothy T. Pennucci, Benetge B. P. Perera, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Laura Salo, Shashwat C. Sardesai, Carl Schmiedekamp, Ann Schmiedekamp, Kai Schmitz, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Abhimanyu Susobhanan, Joseph K. Swiggum, Stephen R. Taylor, Jacob E. Turner, Caner Unal, Michele Vallisneri, Sarah J. Vigeland, Haley M. Wahl, Qiaohong Wang, Caitlin A. Witt, Olivia Young, and The NANOGrav Collaboration

Subjects
Millisecond pulsars, Pulsar timing method, Time series analysis, Pulsars, Gravitational waves, Astrophysics, QB460-466
Abstract

We present observations and timing analyses of 68 millisecond pulsars (MSPs) comprising the 15 yr data set of the North American Nanohertz Observatory for Gravitational Waves (NANOGrav). NANOGrav is a pulsar timing array (PTA) experiment that is sensitive to low-frequency gravitational waves (GWs). This is NANOGrav’s fifth public data release, including both “narrowband” and “wideband” time-of-arrival (TOA) measurements and corresponding pulsar timing models. We have added 21 MSPs and extended our timing baselines by 3 yr, now spanning nearly 16 yr for some of our sources. The data were collected using the Arecibo Observatory, the Green Bank Telescope, and the Very Large Array between frequencies of 327 MHz and 3 GHz, with most sources observed approximately monthly. A number of notable methodological and procedural changes were made compared to our previous data sets. These improve the overall quality of the TOA data set and are part of the transition to new pulsar timing and PTA analysis software packages. For the first time, our data products are accompanied by a full suite of software to reproduce data reduction, analysis, and results. Our timing models include a variety of newly detected astrometric and binary pulsar parameters, including several significant improvements to pulsar mass constraints. We find that the time series of 23 pulsars contain detectable levels of red noise, 10 of which are new measurements. In this data set, we find evidence for a stochastic GW background.

Published
2023
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12. The NANOGrav 15 yr Data Set: Detector Characterization and Noise Budget

Author

Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Paul T. Baker, Bence Bécsy, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Maria Charisi, Shami Chatterjee, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. DeCesar, Paul B. Demorest, Timothy Dolch, Brendan Drachler, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nate Garver-Daniels, Peter A. Gentile, Joseph Glaser, Deborah C. Good, Lydia Guertin, Kayhan Gültekin, Jeffrey S. Hazboun, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Matthew Kerr, Joey S. Key, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Natasha McMann, Bradley W. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Benetge B. P. Perera, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Shashwat C. Sardesai, Ann Schmiedekamp, Carl Schmiedekamp, Kai Schmitz, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Abhimanyu Susobhanan, Joseph K. Swiggum, Stephen R. Taylor, Jacob E. Turner, Caner Unal, Michele Vallisneri, Sarah J. Vigeland, Haley M. Wahl, Caitlin A. Witt, Olivia Young, and The NANOGrav Collaboration

Subjects
Millisecond pulsars, Pulsar timing method, Gravitational wave astronomy, Gravitational wave detectors, Radio astronomy, Astrophysics, QB460-466
Abstract

Pulsar timing arrays (PTAs) are galactic-scale gravitational wave (GW) detectors. Each individual arm, composed of a millisecond pulsar, a radio telescope, and a kiloparsecs-long path, differs in its properties but, in aggregate, can be used to extract low-frequency GW signals. We present a noise and sensitivity analysis to accompany the NANOGrav 15 yr data release and associated papers, along with an in-depth introduction to PTA noise models. As a first step in our analysis, we characterize each individual pulsar data set with three types of white-noise parameters and two red-noise parameters. These parameters, along with the timing model and, particularly, a piecewise-constant model for the time-variable dispersion measure, determine the sensitivity curve over the low-frequency GW band we are searching. We tabulate information for all of the pulsars in this data release and present some representative sensitivity curves. We then combine the individual pulsar sensitivities using a signal-to-noise ratio statistic to calculate the global sensitivity of the PTA to a stochastic background of GWs, obtaining a minimum noise characteristic strain of 7 × 10 ^−15 at 5 nHz. A power-law-integrated analysis shows rough agreement with the amplitudes recovered in NANOGrav’s 15 yr GW background analysis. While our phenomenological noise model does not model all known physical effects explicitly, it provides an accurate characterization of the noise in the data while preserving sensitivity to multiple classes of GW signals.

Published
2023
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13. The NANOGrav 15 yr Data Set: Search for Signals from New Physics

Author

Adeela Afzal, Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Paul T. Baker, Bence Bécsy, Jose Juan Blanco-Pillado, Laura Blecha, Kimberly K. Boddy, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, Rand Burnette, Robin Case, Maria Charisi, Shami Chatterjee, Katerina Chatziioannou, Belinda D. Cheeseboro, Siyuan Chen, Tyler Cohen, James M. Cordes, Neil J. Cornish, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Curt J. Cutler, Megan E. DeCesar, Dallas DeGan, Paul B. Demorest, Heling Deng, Timothy Dolch, Brendan Drachler, Richard von Eckardstein, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nate Garver-Daniels, Peter A. Gentile, Kyle A. Gersbach, Joseph Glaser, Deborah C. Good, Lydia Guertin, Kayhan Gültekin, Jeffrey S. Hazboun, Sophie Hourihane, Kristina Islo, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Luke Zoltan Kelley, Matthew Kerr, Joey S. Key, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Vincent S. H. Lee, Natalia Lewandowska, Rafael R. Lino dos Santos, Tyson B. Littenberg, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Natasha McMann, Bradley W. Meyers, Patrick M. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Jonathan Nay, Priyamvada Natarajan, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Benetge B. P. Perera, Polina Petrov, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Shashwat C. Sardesai, Ann Schmiedekamp, Carl Schmiedekamp, Kai Schmitz, Tobias Schröder, Levi Schult, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Peter Stratmann, Jerry P. Sun, Abhimanyu Susobhanan, Joseph K. Swiggum, Jacob Taylor, Stephen R. Taylor, Tanner Trickle, Jacob E. Turner, Caner Unal, Michele Vallisneri, Sonali Verma, Sarah J. Vigeland, Haley M. Wahl, Qiaohong Wang, Caitlin A. Witt, David Wright, Olivia Young, Kathryn M. Zurek, and The NANOGrav Collaboration

Subjects
Gravitational waves, Cosmology, Particle astrophysics, Gravitational wave sources, Astrophysics, QB460-466
Abstract

The 15 yr pulsar timing data set collected by the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) shows positive evidence for the presence of a low-frequency gravitational-wave (GW) background. In this paper, we investigate potential cosmological interpretations of this signal, specifically cosmic inflation, scalar-induced GWs, first-order phase transitions, cosmic strings, and domain walls. We find that, with the exception of stable cosmic strings of field theory origin, all these models can reproduce the observed signal. When compared to the standard interpretation in terms of inspiraling supermassive black hole binaries (SMBHBs), many cosmological models seem to provide a better fit resulting in Bayes factors in the range from 10 to 100. However, these results strongly depend on modeling assumptions about the cosmic SMBHB population and, at this stage, should not be regarded as evidence for new physics. Furthermore, we identify excluded parameter regions where the predicted GW signal from cosmological sources significantly exceeds the NANOGrav signal. These parameter constraints are independent of the origin of the NANOGrav signal and illustrate how pulsar timing data provide a new way to constrain the parameter space of these models. Finally, we search for deterministic signals produced by models of ultralight dark matter (ULDM) and dark matter substructures in the Milky Way. We find no evidence for either of these signals and thus report updated constraints on these models. In the case of ULDM, these constraints outperform torsion balance and atomic clock constraints for ULDM coupled to electrons, muons, or gluons.

Published
2023
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14. Touristic cultural determinants in Canada based on the authorial route of cultural heritage in the Alberta province

Author

Kamila Ziółkowska-Weiss and Natalia Lewandowska

Subjects
Alberta, Canada, cultural conditions, cultural heritage, tourism, Industries. Land use. Labor, HD28-9999
Abstract

Important elements of the trail include its tourist development. It is of great importance in drawing in tourists to visit a particular attraction or region. It is a special element in the development of tourism space. It increases attractiveness of the reception area, similarly to catering or accommodation facilities. The created network of the tourist routes is considered as internal accessibility of the region. The trail that is well-organised and adapted to the conditions, allows for a wide selection of active forms of spending free time. The work focuses on the development of the cultural heritage trail in the province of Alberta (Canada). Based on the literature analysis, the trail was defined as a tourist attraction in itself. From the information received it was found that the tourist route is an inseparable part of the tourist product. An important element of the tourist trail is tourism development. The text emphasizes cultural aspect of the original route. The protected areas and the cultural heritage of the Indians have been characterised in particular. As part of the original route, the following were characterised: accommodation, catering, accompanying facilities and threats that may occur during the journey. Based on a review of the literature and the author’s route, the relation between local heritage and cultural tourism was inferred.

Published
2022
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15. Statins in Chronic Kidney Disease—Effects on Atherosclerosis and Cellular Senescence

Author

Piotr Fularski, Julia Krzemińska, Natalia Lewandowska, Ewelina Młynarska, Maciej Saar, Magdalena Wronka, Jacek Rysz, and Beata Franczyk

Subjects
atherosclerosis, senescence, chronic kidney disease, inflammation, statins, Cytology, QH573-671
Abstract

Chronic kidney disease (CKD) is a serious health problem that can affect various systems in the human body. Renal failure promotes mechanisms of premature cellular aging and also features of generalized inflammation in the body, which translates into a close relationship between kidney dysfunction and cardiovascular disease (CVD). As kidney function deteriorates, cardiovascular risk and mortality increase in this group of patients. Oxidative stress and inflammation are two closely related processes that initiate a vicious cycle by activating each other. Together with aging, they represent the key factors that cause and exacerbate CVD in CKD. Patients with CKD are particularly vulnerable to the accumulation of aging endothelial cells, vascular smooth muscle and macrophages, increasing the risk of atherosclerosis. Several mechanisms are known that can lead to the progression of the aforementioned problems, such as the accumulation of uremic toxins, persistent inflammation, impaired lipid and electrolyte metabolism, nitric oxide (NO) deficiency, the increased production of reactive oxygen species (ROS) and damage to deoxyribonucleic acid (DNA) and mitochondria. According to research, we can distinguish a group of drugs that effectively counteract the negative effects of CKD—statins. This is a group of drugs that inhibit 3-hydroxy-3-methylglutaryl-coenzyme-A (HMG-CoA) reductase and affect a number of cellular processes and pathways, resulting in the overall slowing of atherosclerosis and cellular aging.

Published
2023
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16. Big Data - A Complex Analysis of Daily Attitudes as a Modern Inevitable Global Danger

Author

Natalia Lewandowska

Subjects
phishing, digitalization, cybercrimes, industry 4.0, the fourth industrial revolution, big data, globalization, International relations, JZ2-6530, Political science (General), JA1-92
Abstract

In the Fourth Industrial Revolution we already have robots, also there are such technologies as genetic sequencing and editing, artificial intelligence, miniaturized sensors, 3D printing and much more. Digital technologies are constantly being developed with new methods and have been implemented worldwide into various processes and automation systems. The article describes modern digitalization components and analyzes its possible threats. Along with an increase in life comfort, modern civilizations must face with cybercrimes based on data collection, including cyber thefts and hacker attacks. Globalization enables exchanging goods and services between countries of the world. It also gives a tool phishing and illegally access vulnerable information of global enterprises to compete unfairly. Although Big Data can be helpful among organizations, it can also be a mark of the inevitable danger worldwide.

Published
2020
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17. How to Detect an Astrophysical Nanohertz Gravitational Wave Background

Author

Bence Bécsy, Neil J. Cornish, Patrick M. Meyers, Luke Zoltan Kelley, Gabriella Agazie, Akash Anumarlapudi, Anne M. Archibald, Zaven Arzoumanian, Paul T. Baker, Laura Blecha, Adam Brazier, Paul R. Brook, Sarah Burke-Spolaor, J. Andrew Casey-Clyde, Maria Charisi, Shami Chatterjee, Katerina Chatziioannou, Tyler Cohen, James M. Cordes, Fronefield Crawford, H. Thankful Cromartie, Kathryn Crowter, Megan E. DeCesar, Paul B. Demorest, Timothy Dolch, Elizabeth C. Ferrara, William Fiore, Emmanuel Fonseca, Gabriel E. Freedman, Nate Garver-Daniels, Peter A. Gentile, Joseph Glaser, Deborah C. Good, Kayhan Gültekin, Jeffrey S. Hazboun, Sophie Hourihane, Ross J. Jennings, Aaron D. Johnson, Megan L. Jones, Andrew R. Kaiser, David L. Kaplan, Matthew Kerr, Joey S. Key, Nima Laal, Michael T. Lam, William G. Lamb, T. Joseph W. Lazio, Natalia Lewandowska, Tyson B. Littenberg, Tingting Liu, Duncan R. Lorimer, Jing Luo, Ryan S. Lynch, Chung-Pei Ma, Dustin R. Madison, Alexander McEwen, James W. McKee, Maura A. McLaughlin, Natasha McMann, Bradley W. Meyers, Chiara M. F. Mingarelli, Andrea Mitridate, Cherry Ng, David J. Nice, Stella Koch Ocker, Ken D. Olum, Timothy T. Pennucci, Benetge B. P. Perera, Nihan S. Pol, Henri A. Radovan, Scott M. Ransom, Paul S. Ray, Joseph D. Romano, Shashwat C. Sardesai, Ann Schmiedekamp, Carl Schmiedekamp, Kai Schmitz, Brent J. Shapiro-Albert, Xavier Siemens, Joseph Simon, Magdalena S. Siwek, Sophia V. Sosa Fiscella, Ingrid H. Stairs, Daniel R. Stinebring, Kevin Stovall, Abhimanyu Susobhanan, Joseph K. Swiggum, Stephen R. Taylor, Jacob E. Turner, Caner Unal, Michele Vallisneri, Rutger van Haasteren, Sarah J. Vigeland, Haley M. Wahl, Caitlin A. Witt, and Olivia Young

Subjects
Gravitational waves, Gravitational wave sources, Gravitational wave astronomy, Supermassive black holes, Astronomy data analysis, Bayesian statistics, Astrophysics, QB460-466
Abstract

Analyses of pulsar timing data have provided evidence for a stochastic gravitational wave background in the nanohertz frequency band. The most plausible source of this background is the superposition of signals from millions of supermassive black hole binaries. The standard statistical techniques used to search for this background and assess its significance make several simplifying assumptions, namely (i) Gaussianity, (ii) isotropy, and most often, (iii) a power-law spectrum. However, a stochastic background from a finite collection of binaries does not exactly satisfy any of these assumptions. To understand the effect of these assumptions, we test standard analysis techniques on a large collection of realistic simulated data sets. The data-set length, observing schedule, and noise levels were chosen to emulate the NANOGrav 15 yr data set. Simulated signals from millions of binaries drawn from models based on the Illustris cosmological hydrodynamical simulation were added to the data. We find that the standard statistical methods perform remarkably well on these simulated data sets, even though their fundamental assumptions are not strictly met. They are able to achieve a confident detection of the background. However, even for a fixed set of astrophysical parameters, different realizations of the universe result in a large variance in the significance and recovered parameters of the background. We also find that the presence of loud individual binaries can bias the spectral recovery of the background if we do not account for them.

Published
2023
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20. A NICER View of Spectral and Profile Evolution for Three X-ray-Emitting Millisecond Pulsars

Author

Dominick M Rowan, Zaynab Ghazi, Lauren Lugo, Elizabeth Spano, Andrea Lommen, Alice Harding, Christo Venter, Renee Ludlam, Paul S Ray, Matthew Kerr, Zaven Arzoumanian, Slavko Bogdanov, Julia Deneva, Sebastien Guillot, Natalia Lewandowska, Craig B Markwardt, Scott Ransom, Teruaki Enoto, Kent S Wood, and Keith C Gendreau

Subjects
Astrophysics
Abstract

We present two years of Neutron star Interior Composition Explorer (NICER) X-ray observations of three energetic rotation-powered millisecond pulsars (MSPs): PSRs B1937+21, B1821−24, and J0218+4232. We fit Gaussians and Lorentzians to the pulse profiles for different energy sub-bands of the soft X-ray regime to measure the energy dependence of pulse separation and width. We find that the separation between pulse components of PSR J0218+4232 decreases with increasing energy at >3σ confidence. The 95% upper limit on pulse separation evolution for PSRs B1937+21 and B1821−24 is less than 2 milliperiods per keV. Our phase-resolved spectral results provide updated constraints on the non-thermal X-ray emission of these three pulsars. The photon indices of the modeled X-ray emission spectra for each pulse component of PSR B1937+21 are inconsistent with each other at the 90% confidence level, suggesting different emission origins for each pulse. We find that the PSR B1821−24 and PSR J0218+4232 emission spectra are invariant with phase at the 90% confidence level. We describe the implications of our profile and spectral results in the context of equatorial current sheet emission models for these three MSPs with non-thermal, magnetospheric X-ray emission.

Published
2020
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21. Timing six energetic rotation-powered X-ray pulsars, including the fast-spinning young PSR J0058-7218 and Big Glitcher PSR J0537-6910

Author

Wynn C. G. Ho, Lucien Kuiper, Cristóbal M. Espinoza, Sebastien Guillot, Paul S. Ray, D. A. Smith, Slavko Bogdanov, Danai Antonopoulou, Zaven Arzoumanian, Michał Bejger, Teruaki Enoto, Paolo Esposito, Alice K. Harding, Brynmor Haskell, Natalia Lewandowska, Chandreyee Maitra, Georgios Vasilopoulos, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Centre National d'Études Spatiales [Toulouse] (CNES), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire astronomique de Strasbourg (ObAS), and Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Solar and Stellar Astrophysics (astro-ph.SR)
Abstract

Measuring a pulsar's rotational evolution is crucial to understanding the nature of the pulsar. Here we provide updated timing models for the rotational evolution of six pulsars, five of which are rotation phase-connected using primarily NICER X-ray data. For the newly-discovered fast energetic young pulsar, PSR J0058-7218, we increase the baseline of its timing model from 1.4 days to 8 months and not only measure more precisely its spin-down rate nudot = (-6.2324+/-0.0001)x10^-11 Hz s^-1 but also for the first time the second time derivative of spin rate nuddot = (4.2+/-0.2)x10^-21 Hz s^-2. For the fastest and most energetic young pulsar, PSR J0537-6910 (with 16 ms spin period), we detect 4 more glitches, for a total of 15 glitches over 4.5 years of NICER monitoring, and show that its spin-down behavior continues to set this pulsar apart from all others, including a long-term braking index n = -1.234+/-0.009 and interglitch braking indices that asymptote to, 18 pages, 17 figures; accepted for publication in ApJ; very minor edits and no changes to numbers

Published
2023
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22. Enhanced x-ray emission coinciding with giant radio pulses from the Crab Pulsar

Author

Keith C. Gendreau, Alice K. Harding, Slavko Bogdanov, Yoshinori Yonekura, Hiroaki Misawa, Takahiko Aoki, Sebastien Guillot, Zaven Arzoumanian, Tomoaki Oyama, Steve Kenyon, Kazuhiro Takefuji, Zorawar Wadiasingh, Tolga Guver, R. S. Foster, Mamoru Sekido, Katsuaki Asano, Christian Malacaria, Shuta J. Tanaka, Yang Soong, Craig B. Markwardt, Takashi Okajima, Shota Kisaka, Natalia Lewandowska, Chin-Ping Hu, Fuminori Tsuchiya, Paul S. Ray, Hiroshi Takeuchi, Teruaki Enoto, Toshio Terasawa, Shinpei Shibata, Osamu Kameya, Munetoshi Tokumaru, Gaurava K. Jaisawal, Mareki Honma, Wynn C. G. Ho, Yasuhiro Murata, Walid A. Majid, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), and Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Multidisciplinary, Crab Pulsar, Astrophysics::High Energy Astrophysical Phenomena, X-ray, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Wavelength, Microsecond, Pulsar, 0103 physical sciences, Optical emission spectroscopy, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], 010306 general physics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract

Giant radio pulses (GRPs) are sporadic bursts emitted by some pulsars, lasting a few microseconds. GRPs are hundreds to thousands of times brighter than regular pulses from these sources. The only GRP-associated emission outside radio wavelengths is from the Crab Pulsar, where optical emission is enhanced by a few percent during GRPs. We observed the Crab Pulsar simultaneously at X-ray and radio wavelengths, finding enhancement of the X-ray emission by $3.8\pm0.7\%$ (a 5.4$\sigma$ detection) coinciding with GRPs. This implies that the total emitted energy from GRPs is tens to hundreds of times higher than previously known. We discuss the implications for the pulsar emission mechanism and extragalactic fast radio bursts., Comment: 63 pages, 23 figures, 7 Tables. Published in Science

Published
2021
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23. A Detection of Red Noise in PSR J1824–2452A and Projections for PSR B1937+21 Using NICER X-Ray Timing Data

Author

Jeffrey S. Hazboun, Jack Crump, Andrea N. Lommen, Sergio Montano, Samantha J. H. Berry, Jesse Zeldes, Elizabeth Teng, Paul S. Ray, Matthew Kerr, Zaven Arzoumanian, Slavko Bogdanov, Julia Deneva, Natalia Lewandowska, Craig B. Markwardt, Scott Ransom, Teruaki Enoto, Kent S. Wood, Keith C. Gendreau, David A. Howe, and Aditya Parthasarathy

Subjects
High Energy Astrophysical Phenomena (astro-ph.HE), Space and Planetary Science, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM)
Abstract

We have used X-ray data from the Neutron Star Interior Composition Explorer (NICER) to search for long time-scale, correlated variations ("red noise") in the pulse times of arrival from the millisecond pulsars PSR J1824$-$2452A and PSR B1937+21. These data more closely track intrinsic noise because X-rays are unaffected by the radio-frequency dependent propagation effects of the interstellar medium. Our Bayesian search methodology yields strong evidence (natural log Bayes factor of $9.634 \pm 0.016$) for red noise in PSR J1824$-$2452A, but is inconclusive for PSR B1937+21. In the interest of future X-ray missions, we devise and implement a method to simulate longer and higher precision X-ray datasets to determine the timing baseline necessary to detect red noise. We find that the red noise in PSR B1937+21 can be reliably detected in a 5-year mission with a time-of-arrival (TOA) error of 2 microseconds and an observing cadence of 20 observations per month compared to the 5 microsecond TOA error and 11 observations per month that NICER currently achieves in PSR B1937+21. We investigate detecting red noise in PSR B1937+21 with other combinations of observing cadences and TOA errors. We also find that an injected stochastic gravitational wave background (GWB) with an amplitude of $A_{\rm GWB}=2\times10^{-15}$ and spectral index of $\gamma_{\rm GWB}=13/3$ can be detected in a pulsar with similar TOA precision to PSR B1937+21, but with no additional red noise, in a 10-year mission that observes the pulsar 15 times per month and has an average TOA error of 1 microsecond., Comment: 21 pages, 13 figures

Published
2022
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24. Bacteriophages as sources of small non-coding RNA molecules

Author

Sylwia Bloch, Bożena Nejman-Faleńczyk, Natalia Lewandowska, and Grzegorz Węgrzyn

Subjects
Genetics, 0303 health sciences, Bacteria, Virulence, 030306 microbiology, viruses, Structural gene, Biology, Non-coding RNA, 03 medical and health sciences, Lytic cycle, Lysogenic cycle, Gene expression, Gene silencing, RNA, Small Untranslated, Bacteriophages, Molecular Biology, Gene, Lysogeny, 030304 developmental biology, Plasmids
Abstract

Bacteriophages play an essential role in the transferring of genes that contribute to the bacterial virulence and whose products are dangerous to human health. Interestingly, phages carrying virulence genes are mostly temperate and in contrast to lytic phages undergo both lysogenic and lytic cycles. Importantly, expression of the majority of phage genes and subsequent production of phage encoded proteins is suppressed during lysogeny. The expression of the majority of phage genes is tightly linked to lytic development. Among others, small non-coding RNAs (sRNAs) of phage origin are involved in the regulation of phage gene expression and thus play an important role in both phage and host development. In the case of bacteria, sRNAs affect processes such as virulence, colonization ability, motility and cell growth or death. In turn, in the case of phages, they play essential roles during the early stage of infection, maintaining the state of lysogeny and silencing the expression of late structural genes, thereby regulating the transition between phage life cycles. Interestingly, sRNAs have been identified in both lytic and temperate phages and they have been discussed in this work according to this classification. Particular attention was paid to viral sRNAs resembling eukaryotic microRNAs.

Published
2020

25. A NICER View of Spectral and Profile Evolution for Three X-ray Emitting Millisecond Pulsars

Author

Zaven Arzoumanian, Lauren Lugo, Paul S. Ray, Slavko Bogdanov, Julia Deneva, Scott M. Ransom, Matthew Kerr, Elizabeth Spano, Keith C. Gendreau, Christo Venter, Andrea N. Lommen, Sebastien Guillot, Kent S. Wood, Natalia Lewandowska, D. M. Rowan, Craig B. Markwardt, Alice K. Harding, Renee M. Ludlam, Zaynab Ghazi, Teruaki Enoto, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Centre National d'Études Spatiales [Toulouse] (CNES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), and 12006653 - Venter, Christo

Subjects
010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Context (language use), Astrophysics, 7. Clean energy, 01 natural sciences, Neutron stars, X-ray astronomy, Pulsar, Millisecond pulsar, 0103 physical sciences, Emission spectrum, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Millisecond pulsars, Neutron Star Interior Composition Explorer, Astronomy and Astrophysics, Pulse (physics), Neutron star, 13. Climate action, Space and Planetary Science, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

We present two years of Neutron star Interior Composition Explorer (NICER) X-ray observations of three energetic rotation-powered millisecond pulsars (MSPs): PSRs B1937+21, B1821-24, and J0218+4232. We fit Gaussians and Lorentzians to the pulse profiles for different energy sub-bands of the soft X-ray regime to measure the energy dependence of pulse separation and width. We find that the separation between pulse components of PSR J0218+4232 decreases with increasing energy at $\gt 3\sigma$ confidence. The 95% upper limit on pulse separation evolution for PSRs B1937+21 and B1821-24 is less than 2 milliperiods per keV. Our phase-resolved spectral results provide updated constraints on the non-thermal X-ray emission of these three pulsars. The photon indices of the modeled X-ray emission spectra for each pulse component of PSR B1937+21 are inconsistent with each other at the 90% confidence level, suggesting different emission origins for each pulse. We find that the PSR B1821-24 and PSR J0218+4232 emission spectra are invariant with phase at the 90% confidence level. We describe the implications of our profile and spectral results in the context of equatorial current sheet emission models for these three MSPs with non-thermal, magnetospheric X-ray emission., Comment: 16 pages, 13 figures, accepted for publication in ApJ

Published
2020
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26. Large High-precision X-Ray Timing of Three Millisecond Pulsars with $NICER$: Stability Estimates and Comparison with Radio

Author

Samuel R. Price, R. Spiewak, Paul Demorest, Sarah J. Vigeland, Slavko Bogdanov, W. W. Zhu, Timothy Dolch, Michael T. Lam, Julia S. Deneva, Peter A. Gentile, Cherry Ng, Zaven Arzoumanian, Harsha Blumer, D. R. Lorimer, N. Garver-Daniels, Maura McLaughlin, K. S. Wood, Matthew Kerr, J. Doty, Paul S. Ray, Scott M. Ransom, C. B. Markwardt, C. Malacaria, Joseph K. Swiggum, J. A. Ellis, Ingrid H. Stairs, M. L. Jones, Sebastien Guillot, Emmanuel Fonseca, Andrea N. Lommen, Paul R. Brook, Alice K. Harding, Kevin Stovall, Kevin Black, L. Guillemot, Robert D. Ferdman, David J. Nice, Timothy T. Pennucci, Luke M. Winternitz, Ismaël Cognard, M. T. Wolff, E. C. Ferrara, Ryan S. Lynch, H. T. Cromartie, M. E. DeCesar, Paul T. Baker, Natalia Lewandowska, Keith Gendreau, Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010504 meteorology & atmospheric sciences, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, 01 natural sciences, 7. Clean energy, Stability (probability), stars: neutron, Pulsar, Millisecond pulsar, pulsars: general, 0103 physical sciences, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Neutron Star Interior Composition Explorer, Sigma, Order (ring theory), Astronomy and Astrophysics, Interstellar medium, pulsars: individual, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Noise (radio)
Abstract

The Neutron Star Interior Composition Explorer (NICER) is an X-ray astrophysics payload on the International Space Station. It enables unprecedented high-precision timing of millisecond pulsars without the pulse broadening and delays due to dispersion and scattering within the interstellar medium that plague radio timing. We present initial timing results from a year of data on the millisecond pulsars PSR B1937+21 and PSR J0218+4232, and nine months of data on PSR B1821-24. NICER time-of-arrival uncertainties for the three pulsars are consistent with theoretical lower bounds and simulations based on their pulse shape templates and average source and background photon count rates. To estimate timing stability, we use the $\sigma_z$ measure, which is based on the average of the cubic coefficients of polynomial fits to subsets of timing residuals. So far we are achieving timing stabilities $\sigma_z \approx 3 \times 10^{-14}$ for PSR B1937+21 and on the order of $10^{-12}$ for PSRs B1821$-$24 and J0218+4232. Within the span of our \textit{NICER} data we do not yet see the characteristic break point in the slope of $\sigma_z$; detection of such a break would indicate that further improvement in the cumulative root-mean-square (RMS) timing residual is limited by timing noise. We see this break point in our comparison radio data sets for PSR B1821-24 and PSR B1937+21 on time scales of $> 2$ years., Comment: 30 pages, 15 figures; accepted to ApJ

Published
2019
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27. Statistics of VHE gamma-Rays in Temporal Association with Radio Giant Pulses from the Crab Pulsar

Author

J. Palacio, J. M. Paredes, Antonio Stamerra, L. Maraschi, Elina Lindfors, Daniel Mazin, Chiara Righi, Wlodek Bednarek, Alessandro Carosi, P. Temnikov, Pratik Majumdar, N. Torres-Albà, M. V. Fonseca, S. N. Shore, Martin Will, Jose Miguel Miranda, E. Colombo, E. Prandini, Aaron Dominguez, Kari Nilsson, L. O. Takalo, Francesco Longo, Juan Abel Barrio, Masahiro Teshima, Nikola Godinovic, U. Menzel, L. A. Antonelli, Mosè Mariotti, D. Hadasch, J. E. Ward, Alba Fernández-Barral, M. Engelkemeier, Stefano Covino, Martin Makariev, Alexander Hahn, P. Colin, Saverio Lombardi, Andrea Rugliancich, Sidika Merve Colak, Oscar Blanch, Arka Chatterjee, Adrian Biland, Christian Fruck, Tomoki Saito, M. Doert, T. Surić, Shimpei Tsujimoto, M. Garczarczyk, Ana Babić, D. Fidalgo, M. Peresano, Camilla Maggio, J. Rico, S. Schroeder, Ivica Puljak, Ievgen Vovk, M. Vazquez Acosta, D. Dominis Prester, Tarek M. Hassan, B. Biasuzzi, Victoria Moreno, Fabrizio Tavecchio, L. Nogués, E. Moretti, D. Kuveždić, Jose Luis Contreras, Abelardo Moralejo, F. Di Pierro, Yusuke Konno, Juan Cortina, T. Schweizer, J. R. Garcia, Giacomo Bonnoli, A. De Angelis, A. Treves, Vitaly Neustroev, V. Fallah Ramazani, Max Ludwig Ahnen, Wrijupan Bhattacharyya, T. Nagayoshi, Daniela Dorner, Dariusz Gora, Gaia Vanzo, G. Maneva, Junko Kushida, P. Da Vela, Kyoshi Nishijima, U. Barres de Almeida, M. Minev, I. Reichardt, P. Giammaria, A. Niedzwiecki, R. Smits, M. Gaug, Damir Lelas, D. Elsaesser, I. Snidaric, Dorota Sobczyńska, J. Herrera, B. De Lotto, Julian Sitarek, Koji Noda, J. Hose, Elisa Bernardini, Stefano Ansoldi, David Paneque, M. I. Martínez, Riccardo Paoletti, D. Guberman, Marina Manganaro, Sabrina Einecke, D. Galindo, P. Cumani, Konstancja Satalecka, Michele Doro, Dario Hrupec, M. A. Lopez, S. Paiano, Karl Mannheim, P. G. Prada Moroni, Tomislav Terzić, Francesco Dazzi, J. Becerra González, Alessio Berti, Natalia Lewandowska, L. Perri, D. Eisenacher Glawion, Cosimo Nigro, M. Nievas Rosillo, B. Banerjee, C. Arcaro, Lluis Font, Marcel Strzys, R. J. García López, G. Pedaletti, Massimo Persic, Wolfgang Rhode, D. Ninci, M. Hayashida, D. Zarić, Marc Ribó, P. Bangale, Hidetoshi Kubo, R. Mirzoyan, Kazuma Ishio, Rodolfo Carosi, German Research Foundation, Istituto Nazionale di Fisica Nucleare, Istituto Nazionale di Astrofisica, Swiss National Science Foundation, Ministerio de Economía y Competitividad (España), Japan Society for the Promotion of Science, Ministry of Education, Culture, Sports, Science and Technology (Japan), Universidad de Barcelona, Croatian Science Foundation, University of Rijeka, Foundation for Polish Science, Ministério da Ciência, Tecnologia e Inovação (Brasil), Ahnen, M. L., Ansoldi, S., Antonelli, L. A., Arcaro, C., Babic, A., Banerjee, B., Bangale, P., Barres De Almeida, U., Barrio, J. A., Becerra Gonzalez, J., Bednarek, W., Bernardini, E., Berti, A., Bhattacharyya, W., Biasuzzi, B., Biland, A., Blanch, O., Bonnoli, G., Carosi, R., Carosi, A., Chatterjee, A., Colak, S. M., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Cumani, P., Da Vela, P., Dazzi, F., De Angelis, A., De Lotto, B., Di Pierro, F., Doert, M., Dominguez, A., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher Glawion, D., Elsaesser, D., Engelkemeier, M., Fallah Ramazani, V., Fernandez-Barral, A., Fidalgo, D., Fonseca, M. V., Font, L., Fruck, C., Galindo, D., Garcia Lopez, R. J., Garczarczyk, M., Gaug, M., Giammaria, P., Godinovic, N., Gora, D., Guberman, D., Hadasch, D., Hahn, A., Hassan, T., Hayashida, M., Herrera, J., Hose, J., Hrupec, D., Ishio, K., Konno, Y., Kubo, H., Kushida, J., Kuvez Dic, D., Lelas, D., Lewandowska, N., Lindfors, E., Lombardi, S., Longo, F., Lopez, M., Maggio, C., Majumdar, P., Makariev, M., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Mariotti, M., Martinez, M., Mazin, D., Menzel, U., Minev, M., Miranda, J. M., Mirzoyan, R., Moralejo, A., Moreno, V., Moretti, E., Nagayoshi, T., Neustroev, V., Niedzwiecki, A., Nievas Rosillo, M., Nigro, C., Nilsson, K., Ninci, D., Nishijima, K., Noda, K., Nogues, L., Paiano, S., Palacio, J., Paneque, D., Paoletti, R., Paredes, J. M., Pedaletti, G., Peresano, M., Perri, L., Persic, M., Prada Moroni, P. G., Prandini, E., Puljak, I., Garcia, J. R., Reichardt, I., Rhode, W., Ribo, M., Rico, J., Righi, C., Rugliancich, A., Saito, T., Satalecka, K., Schroeder, S., Schweizer, T., Shore, S. N., Sitarek, J., Snidaric, I., Sobczynska, D., Stamerra, A., Strzys, M., Suric, T., Takalo, L., Tavecchio, F., Temnikov, P., Terzic, T., Teshima, M., Torres-Alba, N., Treves, A., Tsujimoto, S., Vanzo, G., Vazquez Acosta, M., Vovk, I., Ward, J. E., Will, M., Zaric, D., and Smits, R.

Subjects
Photon, Radiation mechanisms: non-thermal, Radio continuum: stars, VHE [gamma ray], Astrophysics, 01 natural sciences, Cherenkov, individual, 010303 astronomy & astrophysics, Pulsars: individual: Crab pulsar, pulsar, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), photon, Gamma ray, Astrophysics::Instrumentation and Methods for Astrophysics, imaging, pulsed, Gamma rays: stars, pulsars: individual: Crab pulsar - gamma-rays: stars - radio continuum: stars - radiation mechanics: non-thermal, detector [radio wave], statistics, Crab pulsar, Global Positioning System, stars [Radio continuum], Física nuclear, Astrophysics - High Energy Astrophysical Phenomena, stars, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, pulsars, gamma rays, radio continuum, radiation mechanisms, non-thermal, Astrophysics::Cosmology and Extragalactic Astrophysics, Radio telescope, star [Gamma rays], Pulsar, emission [gamma ray], 0103 physical sciences, 010306 general physics, enhancement, Astrophysics::Galaxy Astrophysics, Cherenkov radiation, non-thermal [Radiation mechanisms], business.industry, Crab Pulsar, stars [Gamma rays], Astronomy and Astrophysics, individual: Crab pulsar [Pulsars], MAGIC, flux, Stars, Space and Planetary Science, correlation, ddc:520, business, statistical
Abstract

[Aims] The aim of this study is to search for evidence of a common emission engine between radio giant pulses (GPs) and very-high-energy (VHE, E > 100 GeV) γ-rays from the Crab pulsar., [Methods] We performed 16 h of simultaneous observations of the Crab pulsar at 1.4 GHz with the Effelsberg radio telescope and the Westerbork Synthesis Radio Telescope (WSRT), and at energies above 60 GeV we used the Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) telescopes. We searched for a statistical correlation between the radio and VHE γ-ray emission with search windows of different lengths and different time lags to the arrival times of a radio GP. A dedicated search for an enhancement in the number of VHE γ-rays correlated with the occurrence of radio GPs was carried out separately for the P1 and P2 phase ranges, respectively., [Results] In the radio data sample, 99444 radio GPs were detected. We find no significant correlation between the GPs and VHE photons in any of the search windows. Depending on phase cuts and the chosen search windows, we find upper limits at a 95% confidence level on an increase in VHE γ-ray events correlated with radio GPs between 7% and 61% of the average Crab pulsar VHE flux for the P1 and P2 phase ranges, respectively. This puts upper limits on the flux increase during a radio GP between 12% and 2900% of the pulsed VHE flux, depending on the search window duration and phase cuts. This is the most stringent upper limit on a correlation between γ-ray emission and radio GPs reported so far., The financial support of the German BMBF and MPG, the Italian INFN and INAF, the Swiss National Fund SNF, the ERDF under the Spanish MINECO (FPA2015-69818-P, FPA2012-36668, FPA2015-68378-P, FPA2015-69210-C6-2-R, FPA2015-69210-C6-4-R, FPA2015-69210-C6-6-R, AYA2015-71042-P, AYA2016-76012-C3-1-P, ESP2015-71662-C2-2-P, CSD2009-00064), and the Japanese JSPS and MEXT is gratefully acknowledged. This work was also supported by the Spanish Centro de Excelencia “Severo Ochoa” SEV-2012-0234 and SEV-2015-0548, and Unidad de Excelencia “María de Maeztu” MDM-2014-0369, by the Croatian Science Foundation (HrZZ) Project 09/176 and the University of Rijeka Project 13.12.1.3.02, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, the Polish National Research Centre grant UMO-2016/22/M/ST9/00382 and by the Brazilian MCTIC, CNPq and FAPERJ.

Published
2019
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28. The Pulsar Search Collaboratory: Current Status and Future Prospects

Author

John Stewart, Shirley Au, Aubrey Roy, Natalia Lewandowska, Sue Ann Heatherly, Cabot Zabriskie, Duncan R. Lorimer, Joseph K. Swiggum, Harsha Blumer, Kathryn Williamson, Ryan S. Lynch, and Maura McLaughlin

Subjects
Medical education, business.industry, Process (engineering), 4. Education, Evaluation data, West virginia, Physics - Physics Education, General Physics and Astronomy, Information technology, FOS: Physical sciences, Collaboratory, 01 natural sciences, Pulsar, Observatory, Physics Education (physics.ed-ph), 0103 physical sciences, ComputingMilieux_COMPUTERSANDEDUCATION, Observational study, 010306 general physics, business, Astrophysics - Instrumentation and Methods for Astrophysics, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Mathematics
Abstract

The Pulsar Search Collaboratory (PSC) is a collaboration between the Green Bank Observatory and West Virginia University, funded by the National Science Foundation. The PSC program is currently expanding nationwide and engages high school students, teachers, and undergraduate mentors in real-world research by searching for pulsars in data collected with the 100-m Green Bank Telescope. In the process, students learn about observational radio astronomy, radio frequency interference, pulsar timing, and data analysis procedures. The primary goals of the PSC are to stimulate student interest in Science, Technology, Engineering, and Mathematics (STEM) careers, to prepare teachers in implementing authentic research with students by training them within a professional scientific community, and to promote student use of information technologies through online activities and workshops. In this paper, we provide an overview of pulsar science and the data analysis students undertake, as well as a general overview of the program. We then discuss evaluation data collected from participants through a series of survey questions to determine if the program's initial goals were met. The program had a positive impact on the students according to multiple measures, in particular, on their understanding of the nature of scientific inquiry and motivation to pursue STEM career paths., Comment: 10 pages, 3 figures, Accepted for publication in American Journal of Physics

Published
2019
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29. Meshing strategy for bifurcation arteries in the context of blood flow simulation accuracy

Author

Natalia Lewandowska and Jędrzej Mosiężny

Subjects
lcsh:GE1-350, 0303 health sciences, Aspect ratio, Skew, Context (language use), Geometry, 02 engineering and technology, Flight control surfaces, 03 medical and health sciences, Boundary layer, 0202 electrical engineering, electronic engineering, information engineering, 020201 artificial intelligence & image processing, Polygon mesh, Prism, Bifurcation, lcsh:Environmental sciences, 030304 developmental biology, Mathematics
Abstract

The study presents a mesh dependency study for a carotid artery bifurcation geometry of a real-life specimen. The results of time-averaged velocity profiles at artery control surfaces and wall shear stresses are compared between a set of structured and unstructured meshes, with varying non–dimensional boundary layer first element thickness (y+) parameter. A set of four meshes in total is considered: a full–hexagonal structured mesh, an unstructured tetrahedral mesh with prism inflation layer, both created for y+=1 and y+=30. Apart from numerical results, overall mesh creation work time, overall analysisstability are compared with the mesh quality results: cell non–orthogonality, cell skew and aspect ratio. Numerical results are validated against results of real–life CT examination performed in Poznań Medical University.

Published
2019

30. Swirled injector modeling for cavitating multiphase flow

Author

Jędrzej Mosędrżny, Natalia Lewandowska, and Bartosz Ziegler

Subjects
Propellant, lcsh:GE1-350, Materials science, business.industry, Multiphase flow, 0211 other engineering and technologies, 02 engineering and technology, Injector, Mechanics, 010501 environmental sciences, 01 natural sciences, law.invention, Homogeneous, law, Cavitation, Heat exchanger, Rocket engine, 021108 energy, business, Body orifice, lcsh:Environmental sciences, 0105 earth and related environmental sciences
Abstract

The goal of this study is to present a comparison between different approaches to multiphase injection modeling of self-pressurized rocket engine propellant. Swirled, tangential orifice injector of nitrous oxide, for an “N” class hybrid rocket motor is the object of the study. A brief descriptionof the injector purpose and geometry is provided, followed by a description of different approaches for flow modeling. Examined techniques range from 0D, Homogeneous Equilibrium Model (HEM) to 3D multiphase with mass and heat exchange between phases. Results of analyses are provided and compared with experimental data. The discrepancies between results are of significant magnitude but expected nature. Co clusions about most feasible approaches for engineering calculations are drawn.

Published
2019

31. The Impact of Patches on Blood Flow Disorders In Carotid Artery

Author

Maciej Micker, Andrzej Frąckowiak, Paweł Chęciński, Michał Ciałkowski, Natalia Lewandowska, and Marcin Warot

Subjects
medicine.medical_treatment, Lumen (anatomy), Blood flow, Anatomy, medicine.disease, Flow separation, Stenosis, medicine.anatomical_structure, medicine.artery, medicine, Internal carotid artery, Surgical incision, Artery, Endarterectomy
Abstract

The atherosclerotic plaques are surgically removed by endarterectomy of the common and internal carotid artery wall, removal of lesions, and suturing the artery again. To avoid arterial lumen stenosis, sewing a patch in the incision area is indicated, which will cause a slight expansion of the flow lumen. The channel expansion causes a positive tension gradient, enhancing separation of the parietal layer and occurrence of whirlpools. The latter may cause plaque redeposition. The selection of the patch size is not described in detail in the literature and is based on the surgeon’s experience and intuition. The purpose of the studies is to determine the maximum patch width per surgical incision at which no flow separation will occur. To determine the geometry of the channel with a patch sewn in, an equation was determined to reflect the course of the arterial wall curves by math functions. The artery radius, the maximum expansion radius, and the length of the patch sewn in have been assumed as the input parameters that define the boundary conditions necessary for the determination of polynomial coefficients. By a gradual increase of the maximum radius, a geometry group was determined, which was the starting point for numerical simulations. The simulations were made with the use of Fluent. The increasing of the maximum radius was continued until the separation of the parietal layer was detected and whirlpools occurred. The results showed that when the maximum radius is 30% greater in relation to the arterial radius, whirlpools occur, which in consequence may lead to plaque redeposition.

Published
2019
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32. A new concept of surgical patch used in vascular surgery

Author

Natalia Lewandowska and Michał Ciałkowski

Subjects
0301 basic medicine, lcsh:GE1-350, medicine.medical_specialty, Computer science, Geometric shape, Blood flow, Wall shear, Vascular surgery, Flow field, 03 medical and health sciences, 030104 developmental biology, 0302 clinical medicine, medicine.anatomical_structure, Surgical patch, medicine, 030217 neurology & neurosurgery, lcsh:Environmental sciences, Artery, Biomedical engineering
Abstract

During the surgery of atherosclerotic plaques removal, a longitudinal artery incision is made. Frequently used practice is sewing a patch in the incision area. It reduces the risk of narrowing of the artery but also causes its widening. The channel expansion leads to the enhancing separation of the boundary layer and vortexes creation. The selection of the patch size is based on the surgeon’s experience. The purpose of the studies is to determine a new geometric concept of a patch. The resultingpatch is fully parameterizedand can be influenced by its geometric shape, adapting it to the patient’s diameter. Simulations of blood flow in the artery were performed, with the patch used during the surgery and a patch developed by the authors. The analysis of the flow field in terms of the wall shear stresses (WSS) and velocity distribution has shown, that the patch developed by authors give the most satisfactory results.

Published
2019

33. Microwave-Assisted Degradation of Biomass with the Use of Acid Catalysis

Author

Natalia Lewandowska, Dawid Mikulski, and Grzegorz Kłosowski

Subjects
020209 energy, Biomass, 02 engineering and technology, 010501 environmental sciences, Xylose, lcsh:Chemical technology, Furfural, 01 natural sciences, Catalysis, microwave-assisted degradation, lcsh:Chemistry, chemistry.chemical_compound, Acid catalysis, Nitric acid, 0202 electrical engineering, electronic engineering, information engineering, lcsh:TP1-1185, Hemicellulose, Physical and Theoretical Chemistry, acid catalysis, 0105 earth and related environmental sciences, biomass, fungi, food and beverages, Sulfuric acid, lcsh:QD1-999, chemistry, Nuclear chemistry
Abstract

The aim of the study was to assess the effectiveness of microwave pretreatment combined with acid catalysis in the decomposition of various types of biomass (pine and beech chips and hemp stems). It was clearly demonstrated that sulfuric acid was a catalyst enabling the most effective decomposition of the tested plant biomass, guaranteeing the highest concentrations of simple sugars released. Acid catalysis with 1% v/v sulfuric acid combined with microwave radiation provided high glucose concentrations of 89.8 &plusmn, 3.4, 170.4 &plusmn, 2.4 and 164.6 &plusmn, 4.6 mg/g for pine chips, beech chips and hemp stems, respectively. In turn, the use of nitric acid promoted the degradation of hemicellulose, which resulted in high concentrations of galactose and xylose, i.e., 147.6 &plusmn, 0.6, 163.6 &plusmn, 0.4 and 134.9 &plusmn, 0.8 mg/g of pine chips, beech chips and hemp stems, respectively, while glucose levels remained relatively low. It was also demonstrated that the undesirable dehydration of sugars such as glucose and xylose is more pronounced in sulfuric acid than nitric acid processes. The use of H2SO4 and increased pressure generated 5-hydroxymethylfurfural (5-HMF) and furfural at a concentration of ca. 12 and 6 mg/g, 10 and 45 mg/g and 14 and 30 mg/g, of pine chips, beech chips and hemp shoots, respectively. Our studies confirmed the usefulness of the combined use of microwaves and acid catalysis in the degradation of softwood, hardwood and non-wood plant biomass. It should be emphasized that obtaining high concentrations of released simple sugars (as potential substrates in biosynthesis), while maintaining low levels of toxic by-products (inhibitors), requires precise selection of process parameters such as pressure, exposition time and type of acid catalyst.

Published
2020
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34. Impact of the artery diameter and the surgical patch geometry on the boundary layer thickness and wall shear stresses distribution

Author

Joanna Jójka, Michał Ciałkowski, Bartosz Ziegler, and Natalia Lewandowska

Subjects
Materials science, 020209 energy, Geometry, 02 engineering and technology, Computational fluid dynamics, Boundary layer thickness, Industrial and Manufacturing Engineering, Viscosity, 020401 chemical engineering, medicine.artery, 0202 electrical engineering, electronic engineering, information engineering, medicine, Common carotid artery, 0204 chemical engineering, Electrical and Electronic Engineering, Civil and Structural Engineering, Polynomial (hyperelastic model), business.industry, Mechanical Engineering, Building and Construction, Blood flow, Pollution, Non-Newtonian fluid, General Energy, medicine.anatomical_structure, business, Artery
Abstract

Article presents results of the numerical study concerning nature of blood flow in the post-surgical artery. The research focuses on the development of geometric variants of patches sewn into the common carotid artery during surgery of the atherosclerotic plaque removal. Based on analytical methods, the geometry of the patch described by the polynomial function has been developed. The simulations of blood flow in the arteries with the sewn patch were performed. The study includes the influence of the patient’s diameter, the width and length of the chosen patch on blood flow disorders. The study results comprise the development of software that with the use on input data related to arterial geometry, patch length and patient’s blood parameters (affecting the fluid density and viscosity), shall generate an accurate contour of the patch of width in the selected range.

Published
2020
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35. MAGIC detection of short-term variability of the high-peaked BL Lac object 1ES 0806+524

Author

A. De Angelis, A. Treves, Vitaly Neustroev, R. Zanin, Adrian Biland, J. Rico, G. Maneva, Dario Hrupec, Thomas Bretz, M. Palatiello, Dario Gasparrini, I. Lozano, M. A. Lopez, A. González Muñoz, Louis Antonelli, Walter Max-Moerbeck, Diego F. Torres, Jelena Aleksić, R. López-Coto, X. Paredes-Fortuny, A. Niedzwiecki, D. Nakajima, Julian Sitarek, Francesco Dazzi, A. Fernández-Barral, Patrick Vogler, P. Munar-Adrover, J. M. Paredes, J. Kushida, Jose Luis Contreras, Masahiro Teshima, Ivica Puljak, Filippo D'Ammando, Daniela Dorner, K. Mallot, Wolfgang Rhode, Pierre Colin, R. J. García López, Elina Lindfors, A. Sillanpää, Juan Abel Barrio, David Paneque, Juan Cortina, C. Fruck, M. Gaug, D. Fidalgo, T. Toyama, Antonio Stamerra, Daniel Mazin, Takashi Saito, J. Krause, W. Bednarek, J. Herrera, B. De Lotto, Fabrizio Tavecchio, Julia Thaele, S. N. Shore, K. Berger, Ll. Font, Koji Noda, Reiko Orito, Elisa Bernardini, J. Hose, I. Snidaric, J. L. Richards, D. Elsaesser, E. de Oña Wilhelmi, Francesco Longo, H. Takami, Abelardo Moralejo, K. Nishijima, F. Di Pierro, C. Delgado Mendez, D. Dominis Prester, T. Steinbring, Massimo Persic, Yusuke Konno, Juri Poutanen, E. Lorenz, M. Hayashida, Stefano Covino, G. De Caneva, M. V. Fonseca, Kari Nilsson, K. Kodani, Y. Hanabata, K. Saito, G. Bonnoli, Talvikki Hovatta, M. Will, Marc Ribó, D. Tescaro, P. Antoranz, Konstancja Satalecka, R. Reinthal, P. Temnikov, Michele Doro, M. L. Knoetig, S. Buson, Razmik Mirzoyan, Hidetoshi Kubo, P. G. Prada Moroni, D. Garrido Terrats, Damir Lelas, V. Scalzotto, Nikola Godinovic, Benito Marcote, Dorota Sobczyńska, Oscar Blanch, Ana Babić, P. Da Vela, Stefano Ansoldi, T. Schweizer, Riccardo Paoletti, E. Prandini, F. Borracci, Alessandro Carosi, D. Hadasch, Jose Miguel Miranda, C. Schultz, V. Scapin, Anthony C. S. Readhead, M. Strzys, L. Maraschi, B. Biasuzzi, Tomislav Terzić, D. Galindo, M. I. Martínez, P. Bangale, Sabrina Einecke, S. R. Gozzini, J. Rodriguez Garcia, M. Makariev, U. Menzel, W. Idec, E. Colombo, L. O. Takalo, Mosè Mariotti, A.-K. Overkemping, Saverio Lombardi, Hanna Kellermann, K. Frantzen, V. Kadenius, S. Bonnefoy, S. Paiano, Karl Mannheim, D. Eisenacher, E. Carmona, Markus Garczarczyk, Alicia López-Oramas, Natalia Lewandowska, A. La Barbera, M. Nievas Rosillo, J. Becerra González, Aalto-yliopisto, Aalto University, Aleksi , J., Ansoldi, Stefano, Antonelli, L. A., Antoranz, P., Babic, A., Bangale, P., Barrio, J. A., Becerra Gonzalez, J., Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., de Ona Wilhelmi, E., Delgado Mendez, C., Di Pierro, F., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Fernandez Barral, A., Fidalgo, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., Garcia Lopez, R. J., Garczarczyk, M., Garrido Terrats, D., Gaug, M., Godinovi , N., Gonzalez Munoz, A., Gozzini, S. R., Hadasch, D., Hanabata, Y., Hayashida, M., Herrera, J., Hose, J., Hrupec, D., Idec, W., Kadenius, V., Kellermann, H., Knoetig, M. L., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lewandowska, N., Lindfors, E., Lombardi, S., Longo, Francesco, Lopez, M., Lopez Coto, R., Lopez Oramas, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martinez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar Adrover, P., Nakajima, D., Neustroev, V., Niedzwiecki, A., Nievas Rosillo, M., Nilsson, K., Nishijima, K., Noda, K., Orito, R., Overkemping, A., Paiano, S., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes Fortuny, X., Persic, M., Poutanen, J., Prada Moroni, P. G., Prandini, E., Puljak, I., Reinthal, R., Rhode, W., Ribo, M., Rico, J., Rodriguez Garcia, J., Saito, T., Saito, K., Satalecka, K., Scalzotto, V., Scapin, V., Schultz, C., Schweizer, T., Shore, S. N., Sillanpaa, A., Sitarek, J., Snidaric, I., Sobczynska, D., Stamerra, A., Steinbring, T., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzi , T., Tescaro, D., Teshima, M., Thaele, J., Torres, D. F., Toyama, T., Treves, A., Vogler, P., Will, M., Zanin, R., Berger, K., Buson, S., D'Ammando, F., Gasparrini, D., Hovatta, T., Max Moerbeck, W., Readhead, A., and Richards, J.

Subjects
radiation mechanisms: non-thermal, galaxies: active, BL Lacertae objects: individual: 1ES 0806+524, galaxies: jets, gamma rays: galaxies, Astrophysics::High Energy Astrophysical Phenomena, astro-ph.GA, galaxies: active, jets [galaxies], Flux, FOS: Physical sciences, radiation mechanisms: non-thermal, BL Lacertae objects: individual: 1ES 0806+524, galaxies: jets, gamma rays: galaxies, individual: 1ES 0806+524 [BL Lacertae objects], Astrophysics, law.invention, law, MAGIC (telescope), Blazar, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), astro-ph.HE, ta115, ta213, Compton scattering, Astronomy, Astronomy and Astrophysics, non-thermal [radiation mechanisms], non-thermal, galaxies: active, BL Lacertae objects: individual: 1ES 0806+524, galaxies: jets, gamma rays: galaxies [radiation mechanisms], Astrophysics - Astrophysics of Galaxies, Galaxies: active, Galaxies: jets, Gamma rays: galaxies, Radiation mechanisms: non-thermal, Space and Planetary Science, Crab Nebula, Astrophysics of Galaxies (astro-ph.GA), active [galaxies], galaxies [gamma rays], ddc:520, Spectral energy distribution, Astrophysics - High Energy Astrophysical Phenomena, BL Lac object, Flare
Abstract

Monthly notices of the Royal Astronomical Society 451(1), 739 - 750 (2015). doi:10.1093/mnras/stv895, The high-frequency-peaked BL Lac (HBL) 1ES 0806+524 (z = 0.138) was discovered in very high energy (VHE) γ-rays in 2008. Until now, the broad-band spectrum of 1ES 0806+524 has been only poorly characterized, in particular at high energies. We analysed multiwavelength observations from γ-rays to radio performed from 2011 January to March, which were triggered by the high activity detected at optical frequencies. These observations constitute the most precise determination of the broad-band emission of 1ES 0806+524 to date. The stereoscopic Major Atmospheric Gamma-Ray Imaging Cherenkov (MAGIC) observations yielded a γ-ray signal above 250 GeV of (3.7 ± 0.7) per cent of the Crab Nebula flux with a statistical significance of 9.9σ. The multiwavelength observations showed significant variability in essentially all energy bands, including a VHE γ-ray flare that lasted less than one night, which provided unprecedented evidence for short-term variability in 1ES 0806+524. The spectrum of this flare is well described by a power law with a photon index of 2.97 ± 0.29 between ∼150 GeV and 1 TeV and an integral flux of (9.3 ± 1.9) per cent of the Crab nebula flux above 250 GeV. The spectrum during the non-flaring VHE activity is compatible with the only available VHE observation performed in 2008 with VERITAS when the source was in a low optical state. The broad-band spectral energy distribution can be described with a one-zone synchrotron self-Compton model with parameters typical for HBLs, indicating that 1ES 0806+524 is not substantially different from the HBLs previously detected., Published by Oxford Univ. Press, Oxford

Published
2015
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36. MAGIC upper limits on the GRB 090102 afterglow

Author

M. Gaug, Elisa Bernardini, Gianluca Giavitto, A. González Muñoz, C. Delgado Mendez, Victor Stamatescu, T. Schweizer, A. De Angelis, Mosè Mariotti, A.-K. Overkemping, D. Dominis Prester, Robert Wagner, L. A. Antonelli, Julian Sitarek, Saverio Lombardi, M. L. Knoetig, P. Antoranz, J. Hose, Natalia Lewandowska, T. Toyama, A. Sillanpää, Nikola Godinovic, Takashi Saito, P. Temnikov, Benito Marcote, Abelardo Moralejo, A. La Barbera, Fabrizio Tavecchio, M. V. Fonseca, A. Bouvier, J. Moldón, D. Garrido Terrats, Konstancja Satalecka, Ll. Font, Reiko Orito, Francisco Prada, W. Idec, Julia Thaele, Michele Doro, M. Palatiello, Dario Hrupec, Jelena Aleksić, M. A. Lopez, E. Colombo, P. Da Vela, V. Scalzotto, Dominik Elsaesser, U. Barres de Almeida, A. Niedzwiecki, M. Doert, Damir Lelas, Fabio Zandanel, Ralph Bock, L. O. Takalo, K. Frantzen, Q. Weitzel, Tihomir Surić, M. Uellenbeck, David Paneque, Francesco Dazzi, Patrick Vogler, Hiroyasu Tajima, I. Snidaric, D. Carreto Fidalgo, Ana Babić, Dorota Sobczyńska, G. De Caneva, U. Menzel, M. Salvati, Stefano Ansoldi, S. Rügamer, Juan Abel Barrio, Riccardo Paoletti, Nina Nowak, Diego F. Torres, A. Herrero, Christian Fruck, S. Partini, M. Hayashida, Francesco Longo, E. Lorenz, S. Paiano, Kari Nilsson, Karl Mannheim, Nijil Mankuzhiyil, K. Berger, P. Munar-Adrover, I. Lozano, D. Hadasch, Giacomo Bonnoli, E. Prandini, J. M. Paredes, M. Garczarczyk, Antonio Stamerra, Silvia Preziuso, Marc Ribó, P. G. Prada Moroni, J. Kushida, Aldo Treves, Jose Luis Contreras, J. Krause, B. De Lotto, Masahiro Teshima, O. Tibolla, Juan Cortina, Martin Makariev, Oscar Blanch, Tomislav Terzić, A. Hadamek, J. Storz, Ivica Puljak, Alicia López-Oramas, Pierre Colin, J. Becerra González, Emanuele Paolo Farina, S. Bonnefoy, Aaron Dominguez, Mario Meucci, R. Mirzoyan, D. Eisenacher, E. Carmona, Daniel Ferenc, Thomas Bretz, S. N. Shore, Wlodek Bednarek, Alessandro Carosi, Ruben Lopez-Coto, Felix Spanier, D. Nakajima, C. Schultz, V. Scapin, Jose Miguel Miranda, F. Borracci, Wolfgang Rhode, Ignasi Reichardt, G. Maneva, R. Zanin, A. Saggion, Adrian Biland, J. Rico, R. Reinthal, L. Maraschi, Elina Lindfors, Daniel Mazin, K. Mallot, R. J. García López, Stefano Covino, S. Sun, Massimo Persic, A. Boller, L. Cossio, D. Tescaro, T. Krähenbühl, K. Saito, J. Masbou, M. I. Martínez, V. Kadenius, S. R. Gozzini, J. Rodriguez Garcia, Daniela Dorner, J., Aleksic, S., Ansoldi, L. A., Antonelli, P., Antoranz, A., Babic, U. B., de Almeida, J. A., Barrio, J. B., Gonzalez, W., Bednarek, K., Berger, E., Bernardini, A., Biland, O., Blanch, R. K., Bock, A., Boller, S., Bonnefoy, G., Bonnoli, F., Borracci, T., Bretz, E., Carmona, A., Carosi, D. C., Fidalgo, P., Colin, E., Colombo, J. L., Contrera, J., Cortina, L., Cossio, S., Covino, P., Da Vela, F., Dazzi, A., De Angeli, G., De Caneva, B., De Lotto, C. D., Mendez, M., Doert, A., Dominguez, D. D., Prester, D., Dorner, M., Doro, D., Eisenacher, D., Elsaesser, E., Farina, D., Ferenc, M. V., Fonseca, L., Font, K., Frantzen, C., Fruck, R. J. G., Lopez, M., Garczarczyk, D. G., Terrat, M., Gaug, G., Giavitto, N., Godinovic, A. G., Munoz, S. R., Gozzini, A., Hadamek, D., Hadasch, A., Herrero, J., Hose, D., Hrupec, W., Idec, V., Kadeniu, M. L., Knoetig, T., Krahenbuhl, J., Krause, J., Kushida, A. L., Barbera, D., Lela, N., Lewandowska, E., Lindfor, S., Lombardi, R., Lopez Coto, M., Lopez, A., Lopez Orama, E., Lorenz, I., Lozano, M., Makariev, K., Mallot, G., Maneva, N., Mankuzhiyil, K., Mannheim, L., Maraschi, B., Marcote, M., Mariotti, M., Martinez, J., Masbou, D., Mazin, U., Menzel, M., Meucci, J. M., Miranda, R., Mirzoyan, J., Moldon, A., Moralejo, P., Munar Adrover, D., Nakajima, A., Niedzwiecki, K., Nilsson, N., Nowak, R., Orito, A., Overkemping, S., Paiano, M., Palatiello, D., Paneque, R., Paoletti, J. M., Parede, S., Partini, M., Persic, F., Prada, P. G. P., Moroni, E., Prandini, S., Preziuso, I., Puljak, I., Reichardt, R., Reinthal, W., Rhode, M., Ribo, J., Rico, J. R., Garcia, S., Rugamer, A., Saggion, K., Saito, T., Saito, M., Salvati, K., Satalecka, V., Scalzotto, V., Scapin, C., Schultz, T., Schweizer, S. N., Shore, A., Sillanpaa, J., Sitarek, I., Snidaric, D., Sobczynska, F., Spanier, V., Stamatescu, A., Stamerra, J., Storz, S., Sun, T., Suric, L., Takalo, F., Tavecchio, P., Temnikov, T., Terzic, D., Tescaro, M., Teshima, J., Thaele, O., Tibolla, D. F., Torre, T., Toyama, A., Treve, M., Uellenbeck, P., Vogler, R. M., Wagner, Q., Weitzel, F., Zandanel, R., Zanin, A., Bouvier, M., Hayashida, H., Tajima, and Longo, Francesco

Subjects
Photon, General, Non-thermal - gamma-ray burst, Radiation mechanisms, Astrophysics::High Energy Astrophysical Phenomena, gamma-ray burst: general, Hadron, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, general [gamma-ray burst], 7. Clean energy, 01 natural sciences, law.invention, Telescope, law, 0103 physical sciences, MAGIC (telescope), 010306 general physics, 010303 astronomy & astrophysics, Cherenkov radiation, High Energy Astrophysical Phenomena (astro-ph.HE), astro-ph.HE, Physics, ta115, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, radiation mechanisms: non-thermal, non-thermal [radiation mechanisms], Afterglow, gamma-rays bursts: general, Space and Planetary Science, ddc:520, Electrónica, Física nuclear, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, Gamma-ray burst, Fermi Gamma-ray Space Telescope
Abstract

Indications of a GeV component in the emission from GRBs are known since the EGRET observations during the 1990's and they have been confirmed by the data of the Fermi satellite. These results have, however, shown that our understanding of GRB physics is still unsatisfactory. The new generation of Cherenkov observatories and in particular the MAGIC telescope, allow for the first time the possibility to extend the measurement of GRBs from several tens up to hundreds of GeV energy range. Both leptonic and hadronic processes have been suggested to explain the possible GeV/TeV counterpart of GRBs. Observations with ground-based telescopes of very high energy photons (E>30 GeV) from these sources are going to play a key role in discriminating among the different proposed emission mechanisms, which are barely distinguishable at lower energies. MAGIC telescope observations of the GRB 090102 (z=1.547) field and Fermi Large Area Telescope (LAT) data in the same time interval are analysed to derive upper limits of the GeV/TeV emission. We compare these results to the expected emissions evaluated for different processes in the framework of a relativistic blast wave model for the afterglow. Simultaneous upper limits with Fermi and a Cherenkov telescope have been derived for this GRB observation. The results we obtained are compatible with the expected emission although the difficulties in predicting the HE and VHE emission for the afterglow of this event makes it difficult to draw firmer conclusions. Nonetheless, MAGIC sensitivity in the energy range of overlap with space-based instruments (above about 40 GeV) is about one order of magnitude better with respect to Fermi. This makes evident the constraining power of ground-based observations and shows that the MAGIC telescope has reached the required performance to make possible GRB multiwavelength studies in the very high energy range., 8 pages, 5 figures, 2 tables. Submitted to MNRAS

Published
2014
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37. Timing Noise analysis of HartRAO pulsars: Possible mode switching in the magnetosphere of PSR J1326-5859

Author

Buchner Sarah, Jaques Maritz, Pieter Meintjes, and Natalia Lewandowska

Subjects
Physics, Radio telescope, Pulsar, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics::Instrumentation and Methods for Astrophysics, Mode switching, Astronomy, Magnetosphere, Noise (radio), Pulse (physics)
Abstract

Timing noise in long-term pulsar timing residuals is challenging our understanding of the present pulsar model and forms part of several key science projects, including the detection of GWs and the development of next-generation instruments for pulsar astronomy. We investigate the timing noise phenomena in PSR J1326-5859 that was observed with the 26m HartRAO radio telescope for several decades. One explanation for timing noise is mode switching in the magnetosphere of the pulsar. In this paper we investigate the possible mode switching seen in the spin-down evolution and the pulse shape parameters of PSR J1326-5859. We also search for possible correlations between the parameter data sets.

Published
2016
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38. The major upgrade of the MAGIC telescopes, Part I: The hardware improvements and the commissioning of the system

Author

R. Zanin, Adrian Biland, I. Lozano, J. Rico, Masahiro Teshima, W. Idec, Takashi Saito, J. Krause, B. De Lotto, Nikola Godinovic, Benito Marcote, Stefano Ansoldi, I. Snidaric, David Fink, K. Mallot, R. J. García López, D. Corti, Alessandro Carosi, Mosè Mariotti, A.-K. Overkemping, J. M. Illa, Riccardo Paoletti, Massimo Persic, Gianluca Giavitto, A. González Muñoz, Reiko Orito, P. Temnikov, M. Palatiello, J. Becerra González, Marcel Strzys, Dario Hrupec, M. Bitossi, Ruben Lopez-Coto, Jose Luis Lemus, D. Nakajima, Elina Lindfors, E. Lorenz, Abelardo Moralejo, Saverio Lombardi, A. Treves, Vitaly Neustroev, M. Makariev, Thomas Bretz, Daniel Mazin, Jose Miguel Miranda, M. A. Lopez, S. Rügamer, Juan Abel Barrio, S. Schmidl, T. Steinbring, Francesco Dazzi, J. M. Paredes, Antonio Stamerra, C. Delgado Mendez, G. Maneva, Stefano Covino, B. Biasuzzi, A. Dettlaff, M. Hayashida, D. Hildebrand, Francesco Longo, G. De Caneva, D. Fidalgo, Daniela Dorner, Jose Luis Contreras, Wolfgang Rhode, M. I. Martínez, Marc Ribó, S. Bonnefoy, K. Saito, Natalia Lewandowska, Patrick Vogler, E. Colombo, M. Gaug, Juan Cortina, D. Tescaro, Roberto Cecchi, P. Bangale, H. Wetteskind, A. La Barbera, A. Deangelis, J. Herrera, Hidetoshi Kubo, Sabrina Einecke, S. R. Gozzini, Luis Ángel Tejedor, M. V. Fonseca, Hanna Kellermann, Koji Noda, Louis Antonelli, G. Bonnoli, J. Rodriguez Garcia, Elisa Bernardini, X. Paredes-Fortuny, J. Hose, U. Menzel, K. Kodani, J. Storz, Yusuke Konno, Christian Fruck, A. Sillanpää, D. Elsaesser, L. O. Takalo, F. Borracci, W. Haberer, H. Takami, Oscar Blanch, K. Frantzen, P. G. Prada Moroni, Diego F. Torres, W. Bednarek, Fabrizio Tavecchio, V. Kadenius, S. Paiano, Ll. Font, D. Garrido Terrats, A. Lorca, Karl Mannheim, O. Tibolla, Alicia López-Oramas, T. Schweizer, Felix Spanier, R. Mirzoyan, P. Munar-Adrover, D. Eisenacher, V. Scalzotto, Markus Garczarczyk, N. Mankuzhiyil, Juri Poutanen, Kyoshi Nishijima, D. Dominis Prester, Y. Hanabata, C. Schultz, V. Scapin, P. Antoranz, M. L. Knoetig, Ana Babić, Julia Thaele, E. Carmona, Kari Nilsson, M. Will, L. Maraschi, E. Prandini, Tomislav Terzić, R. Reinthal, M. Negrello, Damir Lelas, Dorota Sobczyńska, Ivica Puljak, Pierre Colin, E. de Oña Wilhelmi, Jelena Aleksić, A. Niedzwiecki, David Paneque, M. Barcelo, D. Galindo, Konstancja Satalecka, Michele Doro, Julian Sitarek, Daniela Hadasch, T. Toyama, Junko Kushida, P. Da Vela, J. Schlammer, Universitat de Barcelona, Aleksić, J, Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Bangale, P., Barceló, M., Barrio, J. A., Becerra González, J., Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Bitossi, M., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Cecchi, R., Colin, P., Colombo, E., Contreras, J. L., Corti, D., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., Deangelis, A., De Caneva, G., De Lotto, B., De Oña Wilhelmi, E., Delgado Mendez, C., Dettlaff, A., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Fidalgo, D., Fink, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., García López, R. J., Garczarczyk, M., Garrido Terrats, D., Gaug, M., Giavitto, G., Godinović, N., González Muñoz, A., Gozzini, S. R., Haberer, W., Hadasch, D., Hanabata, Y., Hayashida, M., Herrera, J., Hildebrand, D., Hose, J., Hrupec, D., Idec, W., Illa, J. M., Kadenius, V., Kellermann, H., Knoetig, M. L., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lemus, J. L., Lewandowska, N., Lindfors, E., Lombardi, S., Longo, Francesco, López, M., López Coto, R., López Oramas, A., Lorca, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mankuzhiyil, N., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar Adrover, P., Nakajima, D., Negrello, M., Neustroev, V., Niedzwiecki, A., Nilsson, K., Nishijima, K., Noda, K., Orito, R., Overkemping, A., Paiano, S., Palatiello, Michele, Paneque, D., Paoletti, R., Paredes, J. M., Paredes Fortuny, X., Persic, M., Poutanen, J., Prada Moroni, P. G., Prandini, E., Puljak, I., Reinthal, R., Rhode, W., Ribó, M., Rico, J., Rodriguez Garcia, J., Rügamer, S., Saito, T., Saito, K., Satalecka, K., Scalzotto, V., Scapin, V., Schultz, C., Schlammer, J., Schmidl, S., Schweizer, T., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Spanier, F., Stamerra, A., Steinbring, T., Storz, J., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Tejedor, L. A., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thaele, J., Tibolla, O., Torres, D. F., Toyama, T., Treves, A., Vogler, P., Wetteskind, H., Will, M., and Zanin, R.

Subjects
Astrofísica, Physics::Instrumentation and Detectors, MAGIC, Imaging Atmospheric Cherenkov Telescopes, Instruments, TeV astrophysics, Very High Energy Gamma Rays, Stereoscopy, Astrophysics, 01 natural sciences, law.invention, Raigs gamma, law, Overall performance, MAGIC (telescope), TeV, astrophysics, CRAB-NEBULA, PERFORMANCE, STEREO, 010303 astronomy & astrophysics, Physics, Astrophysics::Instrumentation and Methods for Astrophysics, Instrument, Upgrade, ddc:540, Electrónica, Física nuclear, Astrophysics::Earth and Planetary Astrophysics, Electricidad, Astrophysics - Instrumentation and Methods for Astrophysics, TeV astrophysic, Noise (radio), Computer hardware, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, Telescope, 0103 physical sciences, Very High Energy Gamma Ray, Instrumentation and Methods for Astrophysics (astro-ph.IM), Cherenkov radiation, ta115, Telescopis, 010308 nuclear & particles physics, business.industry, Gamma rays, Cherenkov Telescope Array, Imaging Atmospheric Cherenkov Telescope, business, astro-ph.IM, Telescopes
Abstract

The MAGIC telescopes are two Imaging Atmospheric Cherenkov Telescopes (IACTs) located on the Canary island of La Palma. The telescopes are designed to measure Cherenkov light from air showers initiated by gamma rays in the energy regime from around 50 GeV to more than 50 TeV. The two telescopes were built in 2004 and 2009, respectively, with different cameras, triggers and readout systems. In the years 2011-2012 the MAGIC collaboration undertook a major upgrade to make the stereoscopic system uniform, improving its overall performance and easing its maintenance. In particular, the camera, the receivers and the trigger of the first telescope were replaced and the readout of the two telescopes was upgraded. This paper (Part I) describes the details of the upgrade as well as the basic performance parameters of MAGIC such as raw data treatment, dead time of the system, linearity in the electronic chain and sources of noise. In Part II, we describe the physics performance of the upgraded system., 19 pages, 18 figures, accepted by Astroparticle Physics

Published
2016
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39. Insights into the emission of the blazar 1ES 1011+496 through unprecedented broadband observations during 2011 and 2012

Author

Daniela Dorner, E. Prandini, Iain A. Steele, Francesco Dazzi, M. Gaug, J. Herrera, A. Fernández-Barral, M. V. Fonseca, Koji Noda, Elisa Bernardini, E. Colombo, F. Di Pierro, S. Bonnefoy, M. Makariev, Talvikki Hovatta, Ivica Puljak, Pierre Colin, L. O. Takalo, D. Garrido Terrats, J. L. Richards, E. de Oña Wilhelmi, Roberta Zanin, Mosè Mariotti, A.-K. Overkemping, D. Eisenacher, E. Carmona, Markus Garczarczyk, J. Krause, B. De Lotto, Natalia Lewandowska, P. Da Vela, D. Nakajima, M. Hayashida, V. Scalzotto, U. Menzel, R. Reinthal, Juan Abel Barrio, Carole Mundell, Razmik Mirzoyan, U. Barres de Almeida, Abelardo Moralejo, Damir Lelas, K. Nishijima, Saverio Lombardi, P. G. Prada Moroni, Michele Palatiello, T. Schweizer, C. Delgado Mendez, T. Steinbring, P. Temnikov, D. Fidalgo, Anthony C. S. Readhead, Hanna Kellermann, M. I. Martínez, P. Bangale, Dorota Sobczyńska, A. De Angelis, A. Treves, Vitaly Neustroev, D. Dominis Prester, Francesco Longo, A. La Barbera, Juri Poutanen, Ana Babić, Stefano Ansoldi, Sabrina Einecke, S. R. Gozzini, Stefano Covino, Riccardo Paoletti, Nikola Godinovic, Benito Marcote, Elizaveta Rastorgueva-Foi, M. Strzys, Yusuke Konno, Y. Hanabata, Marc Ribó, J. Rodriguez Garcia, M. Nievas Rosillo, Jelena Aleksić, Kazuo Saito, J. Kushida, P. Antoranz, M. L. Knoetig, R. López-Coto, Diego F. Torres, G. Maneva, Antonio Stamerra, A. Niedzwiecki, Hidetoshi Kubo, S. N. Shore, X. Paredes-Fortuny, Jose Luis Contreras, Adrian Biland, Alessandro Carosi, W. Idec, David Sánchez, B. Biasuzzi, D. Tescaro, Tuomas Savolainen, David Paneque, P. Munar-Adrover, Julian Sitarek, K. Frantzen, J. Rico, I. Lozano, C. Fruck, T. Toyama, G. De Caneva, Juan Cortina, Anne Lähteenmäki, Oscar Blanch, K. Kodani, Masahiro Teshima, D. Hadasch, V. Kadenius, Elina Lindfors, Merja Tornikoski, Alexander B. Pushkarev, Daniel Mazin, Matthew L. Lister, Julia Thaele, Konstancja Satalecka, Louis Antonelli, Michele Doro, S. Paiano, Joni Tammi, F. D'Ammando, G. Bonnoli, K. Mallot, Karl Mannheim, Jose Miguel Miranda, R. J. García López, J. Hose, Massimo Persic, A. Sillanpää, D. Elsaesser, Takashi Saito, H. Takami, Eckart Lorenz, Alicia López-Oramas, V. Scapin, Reiko Orito, D. Galindo, J. Becerra González, Dario Hrupec, M. A. Lopez, F. Borracci, J. M. Paredes, A. González Mu. noz, Yuri Y. Kovalev, Kari Nilsson, S. Buson, M. Will, C. Arcaro, I. Snidaric, Thomas Bretz, L. Maraschi, Walter Max-Moerbeck, Tomislav Terzić, Wolfgang Rhode, Patrick Vogler, W. Bednarek, Fabrizio Tavecchio, Ll. Font, Aleksic J, Ansoldi S, Antonelli LA, Antoranz P, Arcaro C, Babic A, Bangale P, de Almeida UB, Barrio JA, Gonzalez JB, Bednarek W, Bernardini E, Biasuzzi B, Biland A, Blanch O, Bonnefoy S, Bonnoli G, Borracci F, Bretz T, Carmona E, Carosi A, Colin P, Colombo E, Contreras JL, Cortina J, Covino S, Da Vela P, Dazzi F, De Angelis A, De Caneva G, De Lotto B, Wilhelmi ED, Mendez CD, Di Pierro F, Prester DD, Dorner D, Doro M, Einecke S, Eisenacher D, Elsaesser D, Fernandez-Barral A, Fidalgo D, Fonseca MV, Font L, Frantzen K, Fruck C, Galindo D, Lopez RJG, Garczarczyk M, Terrats DG, Gaug M, Godinovic N, Munoz AG, Gozzini SR, Hadasch D, Hanabata Y, Hayashida M, Herrera J, Hose J, Hrupec D, Idec W, Kadenius V, Kellermann H, Knoetig ML, Kodani K, Konno Y, Krause J, Kubo H, Kushida J, La Barbera A, Lelas D, Lewandowska N, Lindfors E, Lombardi S, Longo F, Lopez M, Lopez-Coto R, Lopez-Oramas A, Lorenz E, Lozano I, Makariev M, Mallot K, Maneva G, Mannheim K, Maraschi L, Marcote B, Mariotti M, Martinez M, Mazin D, Menzel U, Miranda JM, Mirzoyan R, Moralejo A, Munar-Adrover P, Nakajima D, Neustroev V, Niedzwiecki A, Rosillo MN, Nilsson K, Nishijima K, Noda K, Orito R, Overkemping A, Paiano S, Palatiello M, Paneque D, Paoletti R, Paredes JM, Paredes-Fortuny X, Persic M, Poutanen J, Moroni PGP, Prandini E, Puljak I, Reinthal R, Rhode W, Ribo M, Rico J, Garcia JR, Saito T, Saito K, Satalecka K, Scalzotto V, Scapin V, Schweizer T, Shore SN, Sillanpaa A, Sitarek J, Snidaric I, Sobczynska D, Stamerra A, Steinbring T, Strzys M, Takalo L, Takami H, Tavecchio F, Temnikov P, Terzic T, Tescaro D, Teshima M, Thaele J, Torres DF, Toyama T, Treves A, Vogler P, Will M, Zanin R, Buson S, DAmmando F, Lateenmaki A, Hovatta T, Kovalev YY, Lister ML, Max-Moerbeck W, Mundell C, Pushkarev AB, Rastorgueva-Foi E, Readhead ACS, Richards JL, Tammi J, Sanchez DA, Tornikoski M, Savolainen T, Steele I, Autonomous University of Barcelona, University of Udine, INAF, Osservatorio Astronomico di Roma, University of Siena, University of Padova, University of Rijeka, Max Planck Institute for Physics, Centro Brasileiro de Pesquisas Físicas, Complutense University, University of Maryland, College Park, University of Łódź, Deutsches Elektronen-Synchrotron, Swiss Federal Institute of Technology Zurich, University of Würzburg, CIEMAT, Instituto de Astrofísica de Canarias, Institute of Space Studies of Catalonia, Technische Universität Dortmund, University of Barcelona, Kyoto University, Finnish MAGIC Consortium, Institute for Nuclear Research and Nuclear Energy, Japanese MAGIC Consortium, University of Turku, University of Pisa, Max-Planck-Institut für Physik, ICREA, University of Insubria, Istituto di Astrofisica Spaziale e Fisica Cosmica di Bologna, Department of Radio Science and Engineering, California Institute of Technology, Lebedev Physical Institute, Purdue University, National Radio Astronomy Observatory Socorro, University of Liverpool, Crimean Astrophysical Observatory, Max Planck Institute for Radio Astronomy, Metsähovi Radio Observatory, Université Savoie Mont Blanc, Max-Planck-Institut für Radioastronomie, Aalto-yliopisto, Aalto University, Aleksić, J., Ansoldi, S., Antonelli, L. A., Antoranz, P., Arcaro, C, Babic, A., Bangale, P., Barres De Almeida, U., Barrio, J. A., Becerra González, J., Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., De Oña Wilhelmi, E., Delgado Mendez, C., Di Pierro, F., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Fernández Barral, A., Fidalgo, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., García López, R. J., Garczarczyk, M., Garrido Terrats, D., Gaug, M., Godinović, N., González Muñoz, A., Gozzini, S. R., Hadasch, D., Hanabata, Y., Hayashida, M., Herrera, J., Hose, J., Hrupec, D., Idec, W., Kadenius, V., Kellermann, H., Knoetig, M. L., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lewandowska, N., Lindfors, E., Lombardi, S., Longo, Francesco, López, M., López Coto, R., López Oramas, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar Adrover, P., Nakajima, D., Neustroev, V., Niedzwiecki, A., Nievas Rosillo, M., Nilsson, K., Nishijima, K., Noda, K., Orito, R., Overkemping, A., Paiano, S., Palatiello, Michele, Paneque, D., Paoletti, R., Paredes, J. M., Paredes Fortuny, X., Persic, M., Poutanen, J., Prada Moroni, P. G., Prandini, E., Puljak, I., Reinthal, R., Rhode, W., Ribó, M., Rico, J., Rodriguez Garcia, J., Saito, T., Saito, K., Satalecka, K., Scalzotto, V., Scapin, V., Schweizer, T., Shore, S. N., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Stamerra, A., Steinbring, T., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thaele, J., Torres, D. F., Toyama, T., Treves, A., Vogler, P., Will, M., Zanin, R., Buson, S., D'Ammando, F., Lähteenmäki, A., Hovatta, T., Kovalev, Y. Y., Lister, M. L., Max Moerbeck, W., Mundell, C., Pushkarev, A. B., Rastorgueva Foi, E., Readhead, A. C. S., Richards, J. L., Tammi, J., Sanchez, D. A., Tornikoski, M., Savolainen, T., Steele, I., Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), and Universitat de Barcelona

Subjects
Photon, jets [galaxies], Astrophysics, 7. Clean energy, 01 natural sciences, LARGE-AREA TELESCOPE, law.invention, law, BL Lacertae objects: individual: 1ES 1011+496, galaxies: active, galaxies: jets, gamma rays: galaxies, radiation mechanisms: non-thermal, Astronomy and Astrophysics, Space and Planetary Science, individual: 1ES 1011+496 [BL Lacertae objects], 010303 astronomy & astrophysics, QC, QB, Physics, astro-ph.HE, High Energy Astrophysical Phenomena (astro-ph.HE), Superluminal motion, TEV BLAZARS, Polarization (waves), non-thermal [radiation mechanisms], Cosmology, BL-LACERTAE OBJECTS, ACTIVE GALACTIC NUCLEI, GAMMA-RAY EMISSION, X-RAY, LAC OBJECTS, MAGIC TELESCOPE, CRAB-NEBULA, ENERGY-DISTRIBUTION, active [galaxies], galaxies [gamma rays], Spectral energy distribution, Degree of polarization, Electrónica, Física nuclear, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Telescope, 0103 physical sciences, galaxie [gamma rays], Blazar, Cosmologia, 010308 nuclear & particles physics, Astronomy and Astrophysic, Position angle, Galaxies, Galàxies, jet [galaxies], ddc:520, BL Lacertae objects: individual: 1ES 1011+496 – galaxies: active – galaxies: jets – radiation mechanisms: non-thermal – gamma rays: galaxies
Abstract

1ES 1011+496 $(z=0.212)$ was discovered in very high energy (VHE, E >100 GeV) $\gamma$-rays with MAGIC in 2007. The absence of simultaneous data at lower energies led to a rather incomplete characterization of the broadband spectral energy distribution (SED). We study the source properties and the emission mechanisms, probing whether a simple one-zone synchrotron-self-Compton (SSC) scenario is able to explain the observed broadband spectrum. We analyzed VHE to radio data from 2011 and 2012 collected by MAGIC, $Fermi$-LAT, $Swift$, KVA, OVRO, and Mets\"ahovi in addition to optical polarimetry data and radio maps from the Liverpool Telescope and MOJAVE. The VHE spectrum was fit with a simple power law with a photon index of $3.69\pm0.22$ and a flux above 150 GeV of $(1.46\pm0.16)\times10^{-11}$ ph cm$^{-2}$ s$^{-1}$. 1ES 1011+496 was found to be in a generally quiescent state at all observed wavelengths, showing only moderate variability from radio to X-rays. A low degree of polarization of less than 10% was measured in optical, while some bright features polarized up to 60% were observed in the radio jet. A similar trend in the rotation of the electric vector position angle was found in optical and radio. The radio maps indicated a superluminal motion of $1.8\pm0.4\,c$, which is the highest speed statistically significantly measured so far in a high-frequency-peaked BL Lac. For the first time, the high-energy bump in the broadband SED of 1ES 1011+496 could be fully characterized from 0.1 GeV to 1 TeV which permitted a more reliable interpretation within the one-zone SSC scenario. The polarimetry data suggest that at least part of the optical emission has its origin in some of the bright radio features, while the low polarization in optical might be due to the contribution of parts of the radio jet with different orientations of the magnetic field to the optical emission., Comment: 14 pages, 7 figures

Published
2016
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40. Very high-energy gamma-ray observations of novae and dwarf novae with the MAGIC telescopes

Author

J. Kushida, Jose Luis Contreras, Juan Cortina, Tomislav Terzić, A. De Angelis, A. Treves, Vitaly Neustroev, M. Hayashida, Marc Ribó, Marina Manganaro, P. Bangale, D. Galindo, Hidetoshi Kubo, B. Biasuzzi, Abelardo Moralejo, H. Takami, Vassil Verguilov, G. Maneva, D. Nakajima, Konstancja Satalecka, Michele Doro, Giacomo Bonnoli, Julia Thaele, M. I. Martínez, R. Zanin, Adrian Biland, Arka Chatterjee, P. G. Prada Moroni, T. Steinbring, D. Fidalgo, K. Mallot, R. J. García López, J. Rico, M. Palatiello, Kyoshi Nishijima, Yusuke Konno, Sabrina Einecke, Pratik Majumdar, R. Reinthal, Francesco Dazzi, Gareth Hughes, M. V. Fonseca, K. Kodani, C. Schultz, V. Scapin, J. Rodriguez Garcia, Dominik Elsaesser, U. Barres de Almeida, R. Desiante, Stefano Covino, R. López-Coto, B. Banerjee, Max Ludwig Ahnen, Stefano Ansoldi, A. Niedzwiecki, Riccardo Paoletti, G. De Caneva, Damir Lelas, Massimo Persic, D. Tescaro, David Paneque, K. Saito, J. Palacio, Ievgen Vovk, D. Guberman, Dorota Sobczyńska, Julian Sitarek, J. M. Paredes, Antonio Stamerra, P. Giammaria, L. Maraschi, Nikola Godinovic, Benito Marcote, E. Hays, Elina Lindfors, J. Hose, Daniel Mazin, T. Toyama, Hanna Kellermann, B. De Lotto, T. Schweizer, D. Dominis Prester, Ivica Puljak, S. Bonnefoy, R. Clavero, P. Temnikov, Pierre Colin, L. A. Antonelli, Kari Nilsson, M. Will, K. Frantzen, Thomas Bretz, F. Di Pierro, R. Mirzoyan, Juri Poutanen, D. Garrido Terrats, P. Da Vela, Wlodek Bednarek, Alessandro Carosi, E. de Oña Wilhelmi, Y. Hanabata, J. A. Barrio, P. Antoranz, E. Carmona, Masahiro Teshima, S. Paiano, Wolfgang Rhode, Karl Mannheim, Jose Miguel Miranda, Fabrizio Tavecchio, Alicia López-Oramas, Ana Babić, F. Borracci, I. Snidaric, Natalia Lewandowska, A. La Barbera, D. Eisenacher Glawion, X. Paredes-Fortuny, M. Nievas Rosillo, E. Lorenz, J. Becerra González, Takashi Saito, Reiko Orito, E. Prandini, U. Menzel, Daniela Dorner, Diego F. Torres, M. Garczarczyk, A. Sillanpää, E. Colombo, M. Gaug, J. Herrera, L. O. Takalo, Francesco Longo, Koji Noda, Elisa Bernardini, Lluis Font, Marcel Strzys, Martin Makariev, Oscar Blanch, Alba Fernández-Barral, W. Idec, Christian Fruck, Mosè Mariotti, A.-K. Overkemping, Dario Hrupec, M. A. Lopez, A. González Muñoz, Saverio Lombardi, C. Delgado Mendez, Ahnen, M. L, Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Banerjee, B., Bangale, P., Barres De Almeida, U., Barrio, J. A., Becerra González, J., Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Chatterjee, A., Clavero, R., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., De Oña Wilhelmi, E., Delgado Mendez, C., Di Pierro, F., Dominis Prester, D., Dorner, D., Doro, M., Einecke, S., Eisenacher Glawion, D., Elsaesser, D., Fernández Barral, A., Fidalgo, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., García López, R. J., Garczarczyk, M., Garrido Terrats, D., Gaug, M., Giammaria, P., Godinović, N., González Muñoz, A., Guberman, D., Hanabata, Y., Hayashida, M., Herrera, J., Hose, J., Hrupec, D., Hughes, G., Idec, W., Kellermann, H., Kodani, K., Konno, Y., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lewandowska, N., Lindfors, E., Lombardi, S., Longo, Francesco, López, M., López Coto, R., López Oramas, A., Lorenz, E., Majumdar, P., Makariev, M., Mallot, K., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Nakajima, D., Neustroev, V., Niedzwiecki, A., Nievas Rosillo, M., Nilsson, K., Nishijima, K., Noda, K., Orito, R., Overkemping, A., Paiano, S., Palacio, J., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes Fortuny, X., Persic, M., Poutanen, J., Prada Moroni, P. G., Prandini, E., Puljak, I., Reinthal, R., Rhode, W., Ribó, M., Rico, J., Rodriguez Garcia, J., Saito, T., Saito, K., Satalecka, K., Scapin, V., Schultz, C., Schweizer, T., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Stamerra, A., Steinbring, T., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thaele, J., Torres, D. F., Toyama, T., Treves, A., Verguilov, V., Vovk, I., Will, M., Zanin, R., Desiante, R., Hays, E., and Universitat de Barcelona

Subjects
Proton, Hadron, Astrophysics, 01 natural sciences, 7. Clean energy, law.invention, Raigs gamma, law, Astrophysics::Solar and Stellar Astrophysics, novae, cataclysmic variables, gamma rays: stars, binaries: general, stars: activity, 010303 astronomy & astrophysics, Dwarf nova, Novae, Estels binaris de raigs X, astro-ph.HE, Physics, Novae, cataclysmic variable, cataclysmic variables, Binaries: general, Gamma rays: stars, Novae, cataclysmic variables, Stars: activity, Astronomy and Astrophysics, Space and Planetary Science, Gamma-rays, stars, Binaries, general, Stars, activity, Gamma ray, X-ray binaries, Electrónica, Física nuclear, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, activity [Stars], Astrophysics::High Energy Astrophysical Phenomena, Noves (Estels), Telescope, star [Gamma rays], 0103 physical sciences, New stars, general [Binaries], 010308 nuclear & particles physics, Gamma rays, Astronomy and Astrophysic, 13. Climate action, ddc:520, High Energy Physics::Experiment, Fermi Gamma-ray Space Telescope, Lepton
Abstract

Context. In the last five years the Fermi Large Area Telescope (LAT) instrument detected GeV {\gamma}-ray emission from five novae. The GeV emission can be interpreted in terms of an inverse Compton process of electrons accelerated in a shock. In this case it is expected that protons in the same conditions can be accelerated to much higher energies. Consequently they may produce a second component in the {\gamma}-ray spectrum at TeV energies. Aims. We aim to explore the very-high-energy domain to search for {\gamma}-ray emission above 50 GeV and to shed light on the acceleration process of leptons and hadrons in nova explosions. Methods. We have performed observations with the MAGIC telescopes of the classical nova V339 Del shortly after the 2013 outburst, triggered by optical and subsequent GeV {\gamma}-ray detec- tions. We also briefly report on VHE observations of the symbiotic nova YY Her and the dwarf nova ASASSN-13ax. We complement the TeV MAGIC observations with the analysis of con- temporaneous Fermi-LAT data of the sources. The TeV and GeV observations are compared in order to evaluate the acceleration parameters for leptons and hadrons. Results. No significant TeV emission was found from the studied sources. We computed upper limits on the spectrum and night-by-night flux. The combined GeV and TeV observations of V339 Del limit the ratio of proton to electron luminosities to Lp, Comment: 7 pages, 2 figures, accepted for publication in A&A

Published
2015
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41. A new technology for microfluidic structures preparation based on a photoimageable ceramic

Author

Michal Chudy, Artur Dybko, Zbigniew Magonski, Iwona Wyżkiewicz, Zbigniew Brzozka, Małgorzata Jakubowska, Natalia Lewandowska, and Barbara Dziurdzia

Subjects
Microchannel, Fabrication, Materials science, Microfluidics, Nanotechnology, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, law.invention, Hardware and Architecture, law, visual_art, Screen printing, visual_art.visual_art_medium, Thick film technology, Fluidics, Ceramic, Electrical and Electronic Engineering, Photolithography
Abstract

A new method for fabrication of hybrid ceramic-polymer structures with diversified geometry of microchannel was elaborated. This method is universal, non-complicated, and utilises commercially available materials and basic equipment for thick film technology and photolithography. A microchip for capillary electrophoresis was prepared as an example of microfluidic structure fabrication. The chip was prepared by using a photosensitive paste (dielectric FODEL 6050) which was screen printed onto a ceramic substrate, exposed through an appropriate mask, developed, fired and then glazed. In this way, we obtained the structure which can be bonded with poly(dimethylsiloxane) PDMS after oxygen plasma treatment. The application of transparent PDMS as a seal of the microchannel enabled the optical detection.

Published
2006
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42. Black hole lightning due to particle acceleration at subhorizon scales

Author

J. Kushida, Jose Luis Contreras, Juan Cortina, J. Hose, R. Reinthal, D. Elsaesser, Michele Palatiello, P. Munar-Adrover, Elina Lindfors, Damir Lelas, Dario Hrupec, R. Zanin, Daniel Mazin, D. Nakajima, Victor Stamatescu, M. A. Lopez, Dorota Sobczyńska, Adrian Biland, K. Nishijima, M. Uellenbeck, D. Garrido Terrats, D. Dominis Prester, J. Rico, V. Scalzotto, Christian Fruck, E. Prandini, Stefano Covino, P. G. Prada Moroni, Francesco Longo, F. Borracci, P. Da Vela, Nikola Godinovic, Benito Marcote, Patrick Vogler, Ana Babić, D. Galindo, Yusuke Konno, O. Tibolla, I. Snidaric, M. Makariev, D. Tescaro, P. Temnikov, Ivica Puljak, M. V. Fonseca, A. Sillanpää, Jörn Wilms, G. Bonnoli, L. Maraschi, Pierre Colin, C. Delgado Mendez, S. R. Gozzini, E. de Oña Wilhelmi, Konstancja Satalecka, Julian Sitarek, Michele Doro, A. Treves, Kari Nilsson, Tomislav Terzić, N. Mankuzhiyil, Daniela Hadasch, Jelena Aleksić, Oscar Blanch, Alessandro Carosi, E. Lorenz, Ruben Lopez-Coto, T. Toyama, A. Niedzwiecki, I. Lozano, G. De Caneva, M. Hayashida, David Paneque, S. Bonnefoy, A. González Muñoz, T. Schweizer, Jose Miguel Miranda, E. Colombo, Francesco Dazzi, Masahiro Teshima, G. Maneva, Felix Spanier, Y. Hanabata, Daniela Dorner, C. Schultz, V. Scapin, Miriam Lucio Martinez, S. Rügamer, Juan Abel Barrio, M. Gaug, W. Bednarek, Fabrizio Tavecchio, Ll. Font, Juri Poutanen, Stefano Ansoldi, J. Herrera, Koji Noda, B. Biasuzzi, U. Bach, Marc Ribó, Riccardo Paoletti, P. Antoranz, Elisa Bernardini, Hajime Takami, P. Bangale, J. M. Paredes, Felicia Krauß, Hidetoshi Kubo, Antonio Stamerra, Julia Thaele, K. Kodani, E. Carmona, L. O. Takalo, Louis Antonelli, J. Storz, A. De Angelis, D. Hildebrand, Mosè Mariotti, A.-K. Overkemping, Sabrina Einecke, Saverio Lombardi, J. Rodriguez Garcia, K. Saito, W. Idec, K. Frantzen, V. Kadenius, S. Paiano, Karl Mannheim, Alicia López-Oramas, Natalia Lewandowska, R. Mirzoyan, A. La Barbera, D. Eisenacher, Markus Garczarczyk, X. Paredes-Fortuny, J. Becerra González, Abelardo Moralejo, T. Steinbring, Hanna Kellermann, U. Menzel, Diego F. Torres, J. Krause, B. De Lotto, Takashi Saito, Reiko Orito, Eduardo Ros, Marcel Strzys, Matthias Kadler, K. Mallot, R. J. García López, Massimo Persic, R. Schulz, Thomas Bretz, S. N. Shore, Wolfgang Rhode, Aleksić, J, Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Bangale, P., Barrio, J. A., González, J. Becerra, Bednarek, W., Bernardini, E., Biasuzzi, B., Bil, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., De Oña Wilhelmi, E., Mendez, C. Delgado, Prester, D. Domini, Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., López, R. J. García, Garczarczyk, M., Terrats, D. Garrido, Gaug, M., Godinoviæ, N., Muñoz, A. González, Gozzini, S. R., Hadasch, D., Hanabata, Y., Hayashida, M., Herrera, J., Hildebr, D., Hose, J., Hrupec, D., Idec, W., Kadenius, V., Kellermann, H., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., Barbera, A. La, Lelas, D., Lewowska, N., Lindfors, E., Lombardi, S., Longo, Francesco, López, M., López Coto, R., López Oramas, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mankuzhiyil, N., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Mira, J. M., Mirzoyan, R., Moralejo, A., Munar Adrover, P., Nakajima, D., Niedzwiecki, A., Nilsson, K., Nishijima, K., Noda, K., Orito, R., Overkemping, A., Paiano, S., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes Fortuny, X., Persic, M., Poutanen, J., Moroni, P. G. Prada, Prini, E., Puljak, I., Reinthal, R., Rhode, W., Ribó, M., Rico, J., Garcia, J. Rodriguez, Rügamer, S., Saito, T., Saito, K., Satalecka, K., Scalzotto, V., Scapin, V., Schultz, C., Schweizer, T., Shore, S. N., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Spanier, F., Stamatescu, V., Stamerra, A., Steinbring, T., Storz, J., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thaele, J., Tibolla, O., Torres, D. F., Toyama, T., Treves, A., Uellenbeck, M., Vogler, P., Zanin, R., Kadler, M., Schulz, R., Ros, E., Bach, U., Krauß, F., and Wilms, J.

Subjects
Black Holes, Radio galaxy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Very High Energy Gamma Astronomy, Black Holes, Very High Energy Gamma Astronomy, Active Galactic Nuclei, X-shaped radio galaxy, supermassive black hole, jet formation, IC 310, MAGIC telescopes, Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), astro-ph.HE, Supermassive black hole, ta115, Multidisciplinary, Active Galactic Nuclei, Astronomy and Astrophysics, Galaxy, Intermediate-mass black hole, Stellar black hole, Electrónica, Física nuclear, ddc:500, Spin-flip, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, Schwarzschild radius
Abstract

Supermassive black holes with masses of millions to billions of solar masses are commonly found in the centers of galaxies. Astronomers seek to image jet formation using radio interferometry, but still suffer from insufficient angular resolution. An alternative method to resolve small structures is to measure the time variability of their emission. Here, we report on gamma-ray observations of the radio galaxy IC 310 obtained with the MAGIC telescopes revealing variability with doubling time scales faster than 4.8 min. Causality constrains the size of the emission region to be smaller than 20\% of the gravitational radius of its central black hole. We suggest that the emission is associated with pulsar-like particle acceleration by the electric field across a magnetospheric gap at the base of the radio jet., 19 pages, 10 figures, includes Supplementary Materials

Published
2014
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43. Unprecedented study of the broadband emission of Mrk 421 during flaring activity in March 2010

Author

E. Pueschel, J. Hose, Svetlana G. Jorstad, M. F. Aller, David A. Williams, G. H. Sembroski, D. Nakajima, M. Strzys, R. Welsing, A. Archer, E. Colombo, B. Biasuzzi, F. Borracci, Stefano Ansoldi, Riccardo Paoletti, I. Telezhinsky, Jamie Holder, D. Elsaesser, D. Staszak, Dario Hrupec, L. Ciupik, L. C. Reyes, G. Bonnoli, K. Ragan, M. A. Lopez, N. Galante, Hajime Takami, J. M. Paredes, P. T. Reynolds, Natalia Lewandowska, Hugh D. Aller, L. O. Takalo, G. H. Gillanders, T. Schweizer, Mosè Mariotti, Wystan Benbow, A.-K. Overkemping, D. Hadasch, Victor Stamatescu, J. Biteau, Paul S. Smith, Gordon T. Richards, Wei Cui, A. La Barbera, Sinéad M. Griffin, E. Roache, A. López-Oramas, S. Rügamer, Juan Abel Barrio, J. A. Ros, O. M. Kurtanidze, Alessandro Carosi, Ruben Lopez-Coto, X. Paredes-Fortuny, Mark Gurwell, U. Menzel, Saverio Lombardi, Calvin A. Johnson, P. Kar, M. Villata, K. Mallot, R. J. García López, Felix Spanier, M. Kertzman, A. C. S. Readhead, E. Prandini, D. Galindo, Merja Tornikoski, Yusuke Konno, Diego F. Torres, M. G. Nikolashvili, D. Eisenacher, Antonio Stamerra, K. Kodani, Givi N. Kimeridze, Julian Sitarek, Lorand A. Sigua, K. Nishijima, J. V. Tucci, A. Cesarini, M. Perri, P. Kaaret, J. Storz, D. Dominis Prester, Martin Pohl, C. M. Raiteri, Markus Garczarczyk, C. Fruck, A. Sillanpää, N. Håkansson, M. Makariev, T. Toyama, L. Maraschi, A. Pichel, Jose Miguel Miranda, Matteo Cerruti, Konstancja Satalecka, J. Becerra González, P. Antoranz, Amy Furniss, S. P. Wakely, B. Jordan, Elena G. Larionova, Xuhui Chen, H. C. Lin, Geza Gyuk, Louis Antonelli, Michele Doro, Abelardo Moralejo, Jelena Aleksić, S. McArthur, M. L. Knoetig, P. G. Prada Moroni, P. Munar-Adrover, Ivica Puljak, E. Collins-Hughes, K. Meagher, Nikola Godinovic, Benito Marcote, T. Steinbring, W. Idec, M. V. Fonseca, Pierre Colin, P. Temnikov, M. Hayashida, Patrick Vogler, J. Tyler, A. Niedzwiecki, C. Schultz, V. Scapin, J. H. Buckley, P. Moriarty, Tomislav Terzić, K. Berger, T. Sakamoto, C. Delgado Mendez, S. R. Gozzini, B. McBreen, O. Tibolla, Shan Sun, E. de Oña Wilhelmi, Ivan S. Troitsky, David Paneque, I. Snidaric, Marc Ribó, P. Da Vela, D. Hildebrand, B. Steinke, Steven N. Shore, Q. Feng, K. Frantzen, Massimo Persic, Hidetoshi Kubo, A. Boller, D. A. Morozova, A. Wilhelm, R. Reinthal, Thomas Bretz, Sofia O. Kurtanidze, Kari Nilsson, Elina Lindfors, Justin D. Finke, J. Krause, B. De Lotto, Walter Max-Moerbeck, K. Saito, Razmik Mirzoyan, U. Barres de Almeida, A. González Muñoz, V. Kadenius, Damir Lelas, N. Mankuzhiyil, J. P. Finley, J. S. Perkins, Wen Ping Chen, S. Paiano, E. Lorenz, Karl Mannheim, H. Prokoph, Hanna Kellermann, Daniel Mazin, I. Lozano, Dorota Sobczyńska, J. D. Eisch, Wolfgang Rhode, Daniela Dorner, M. Palatiello, Joseph Moody, Lucy Fortson, M. I. Martínez, M. Gaug, P. Bangale, G. De Caneva, J. Herrera, Matthias Beilicke, Koji Noda, J. Millis, Abraham D. Falcone, Francesco Dazzi, Karlen Shahinyan, Elisa Bernardini, S. Bonnefoy, Sabrina Einecke, J. Rodriguez Garcia, W. Bednarek, Fabrizio Tavecchio, Ll. Font, A. C. Sadun, Anne Lähteenmäki, Stefano Covino, M. J. Lang, A. Varlotta, Masahiro Teshima, A. McCann, Ekaterina Koptelova, A. C. Rovero, J. Kushida, D. Tescaro, Jose Luis Contreras, G. Hughes, M. Uellenbeck, Takashi Saito, Y. Hanabata, A. Popkow, Juan Cortina, V. Bugaev, David Kieda, Reiko Orito, S. Buson, J. L. Richards, Ann E. Wehrle, D. Garrido Terrats, P. Fortin, Oscar Blanch, Ralph Bird, S. Archambault, Valeri M. Larionov, V. Scalzotto, Ana Babić, Julia Thaele, E. Carmona, A. De Angelis, A. Treves, R. A. Ong, G. Maneva, R. Zanin, A. N. Otte, Adrian Biland, J. Rico, Alan P. Marscher, Universitat de Barcelona, Department of Radio Science and Engineering, Aalto-yliopisto, Aalto University, and ~

Subjects
extragalactic background light, Ciencias Físicas, spectral energy-distribution, Flux, Non-thermal / galaxies, Astrophysics, law.invention, Relativistic particle, purl.org/becyt/ford/1 [https], atmospheric cherenkov telescopes, Raigs gamma, bl lacertae objects, law, MAGIC (telescope), Active / BL Lacertae objects, astro-ph.HE, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, individual: Mrk 421 [BL Lacertae objects], education.field_of_study, gamma-ray outburst, non-thermal [radiation mechanisms], BL Lacertae objects: individual: Mrk 421, Galaxies: active, Gamma rays: galaxies, Radiation mechanisms: non-thermal, Astronomy and Astrophysics, Space and Planetary Science, Particle acceleration, NON THERMAL RADIATION, large-area telescope, active [galaxies], galaxies [gamma rays], BL LACERTAE OBJECTS, Electrónica, self-compton model, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, CIENCIAS NATURALES Y EXACTAS, Flare, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, Population, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Radio telescope, radiation mechanisms: non-thermal, gamma rays: galaxies, Radiation mechanisms, BL Lacertae objects: individual, simultaneous multiwavelength observations, AGN, education, Blazar, Individual: Mrk 421 / gamma rays, tev blazars, Gamma rays, Institut für Physik und Astronomie, purl.org/becyt/ford/1.3 [https], Galaxies, Astronomía, x-ray, Galàxies actives, Active galaxies, ddc:520
Abstract

A flare from the TeV blazar Mrk 421, occurring in March 2010, was observed for 13 consecutive days from radio to very high energy (VHE, E > 100 GeV) gamma-rays with MAGIC, VERITAS, Whipple, FermiLAT, MAXI, RXTE, Swift, GASP-WEBT, and several optical and radio telescopes. We model the day-scale SEDs with one-zone and two-zone synchrotron self-Compton (SSC) models, investigate the physical parameters, and evaluate whether the observed broadband SED variability can be associated to variations in the relativistic particle population. Flux variability was remarkable in the X-ray and VHE bands while it was minor or not significant in the other bands. The one-zone SSC model can describe reasonably well the SED of each day for the 13 consecutive days. This flaring activity is also very well described by a two-zone SSC model, where one zone is responsible for the quiescent emission while the other smaller zone, which is spatially separated from the first one, contributes to the daily-variable emission occurring in X-rays and VHE gamma-rays. Both the one-zone SSC and the two-zone SSC models can describe the daily SEDs via the variation of only four or five model parameters, under the hypothesis that the variability is associated mostly to the underlying particle population. This shows that the particle acceleration and cooling mechanism producing the radiating particles could be the main one responsible for the broadband SED variations during the flaring episodes in blazars. The two-zone SSC model provides a better agreement to the observed SED at the narrow peaks of the low- and high-energy bumps during the highest activity, although the reported one-zone SSC model could be further improved by the variation of the parameters related to the emitting region itself ($\delta$, $B$ and $R$), in addition to the parameters related to the particle population., Comment: Published in A&A, 30 pages, 15 figures, 6 tables. Online-data: multi-wavelength light curves (data in Fig. 1) and broadband spectral energy distributions (the data in Figs. 6, and B1-B4) are available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/578/A22. Corresponding authors: David Paneque (dpaneque@mpp.mpg.de), Shangyu Sun (sysun@mpp.mpg.de), Hajime Takami (takami@post.kek.jp)

Published
2014
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44. First broadband characterization and redshift determination of the VHE blazar MAGIC J2001+439

Author

Robert Wagner, Konstancja Satalecka, Michele Doro, K. Nishijima, K. Mallot, R. J. García López, A. Herrero, D. Dominis Prester, M. Uellenbeck, Nina Nowak, J. M. Paredes, A. López-Oramas, J. Kushida, Antonio Stamerra, Jelena Aleksić, Nikola Godinovic, Benito Marcote, Jose Luis Contreras, A. Niedzwiecki, David Paneque, Wlodek Bednarek, Alessandro Carosi, Francisco Prada, J. L. Richards, Juan Cortina, K. Kodani, Ruben Lopez-Coto, Massimo Persic, D. Nakajima, J. Storz, D. Garrido Terrats, Talvikki Hovatta, Patrick Vogler, P. G. Prada Moroni, Valeri M. Larionov, Jose Miguel Miranda, V. Scalzotto, C. Schultz, V. Scapin, Tomislav Terzić, Yusuke Konno, Anthony C. S. Readhead, J. Krause, O. Tibolla, M. Hayashida, B. De Lotto, P. Da Vela, Ana Babić, Hanna Kellermann, L. Maraschi, Elina Lindfors, Kari Nilsson, Daniel Mazin, Marc Ribó, M. V. Fonseca, P. Bangale, Julia Thaele, Hidetoshi Kubo, Stefano Covino, U. Menzel, Emanuele Paolo Farina, A. De Angelis, D. Tescaro, M. Perri, I. Snidaric, Natalia Lewandowska, M. Palatiello, Diego F. Torres, S. Rügamer, Stefano Ansoldi, Juan Abel Barrio, M. I. Martínez, Riccardo Paoletti, Felix Spanier, T. Sakamoto, M. Garczarczyk, E. Lorenz, Hajime Takami, A. La Barbera, L. A. Antonelli, Francesco Dazzi, Sabrina Einecke, P. Antoranz, R. Reinthal, J. Rodriguez Garcia, Dominik Elsaesser, Giacomo Bonnoli, X. Paredes-Fortuny, U. Barres de Almeida, I. Lozano, Fabrizio Tavecchio, Damir Lelas, Ll. Font, Masahiro Teshima, Victor Stamatescu, S. Bonnefoy, R. D. Schwartz, Filippo D'Ammando, Dorota Sobczyńska, R. Mirzoyan, D. Eisenacher, Abelardo Moralejo, P. Temnikov, Fabio Zandanel, Shan Sun, E. Carmona, T. Steinbring, Julian Sitarek, J. Hose, Aaron Dominguez, E. Prandini, Daniela Hadasch, T. Toyama, Aldo Treves, W. Idec, Thomas Bretz, S. N. Shore, Walter Max-Moerbeck, Wolfgang Rhode, K. Frantzen, Ivica Puljak, Tihomir Surić, Pierre Colin, D. Carreto Fidalgo, T. Schweizer, C. Delgado Mendez, S. R. Gozzini, F. Borracci, V. Kadenius, S. Paiano, Karl Mannheim, J. Becerra González, Mario Meucci, F. Verrecchia, E. Colombo, Nijil Mankuzhiyil, P. Munar-Adrover, G. Maneva, Silvia Preziuso, L. O. Takalo, R. Zanin, A. Saggion, Adrian Biland, A. González Muñoz, Mosè Mariotti, A.-K. Overkemping, J. Rico, A. Sillanpää, Daniela Dorner, Takashi Saito, Saverio Lombardi, M. Gaug, Reiko Orito, J. Herrera, Koji Noda, Elisa Bernardini, Christian Fruck, K. Saito, D. Hildebrand, Daniel Ferenc, G. De Caneva, S. Partini, Marcel Strzys, L. C. Reyes, Martin Makariev, Oscar Blanch, M. Doert, Dario Hrupec, M. A. Lopez, Aleksic J, Ansoldi S, Antonelli LA, Antoranz P, Babic A, Bangale P, de Almeida UB, Barrio JA, Gonzalez JB, Bednarek W, Bernardini E, Biland A, Blanch O, Bonnefoy S, Bonnoli G, Borracci F, Bretz T, Carmona E, Carosi A, Fidalgo DC, Colin P, Colombo E, Contreras JL, Cortina J, Covino S, Da Vela P, Dazzi F, De Angelis A, De Caneva G, De Lotto B, Mendez CD, Doert M, Dominguez A, Prester DD, Dorner D, Doro M, Einecke S, Eisenacher D, Elsaesser D, Farina E, Ferenc D, Fonseca MV, Font L, Frantzen K, Fruck C, Lopez RJG, Garczarczyk M, Terrats DG, Gaug M, Godinovic N, Munoz AG, Gozzini SR, Hadasch D, Hayashida M, Herrera J, Herrero A, Hildebrand D, Hose J, Hrupec D, Idec W, Kadenius V, Kellermann H, Kodani K, Konno Y, Krause J, Kubo H, Kushida J, La Barbera A, Lelas D, Lewandowska N, Lindfors E, Lombardi S, Lopez M, Lopez-Coto R, Lopez-Oramas A, Lorenz E, Lozano I, Makariev M, Mallot K, Maneva G, Mankuzhiyil N, Mannheim K, Maraschi L, Marcote B, Mariotti M, Martinez M, Mazin D, Menzel U, Meucci M, Miranda JM, Mirzoyan R, Moralejo A, Munar-Adrover P, Nakajima D, Niedzwiecki A, Nilsson K, Nishijima K, Noda K, Nowak N, Orito R, Overkemping A, Paiano S, Palatiello M, Paneque D, Paoletti R, Paredes JM, Paredes-Fortuny X, Partini S, Persic M, Prada F, Moroni PGP, Prandini E, Preziuso S, Puljak I, Reinthal R, Rhode W, Riboo M, Rico J, Garcia JR, Rugamer S, Saggion A, Saito T, Saito K, Satalecka K, Scalzotto V, Scapin V, Schultz C, Schweizer T, Shore SN, Sillanpaa A, Sitarek J, Snidaric I, Sobczynska D, Spanier F, Stamatescu V, Stamerra A, Steinbring T, Storz J, Strzys M, Sun S, Suric T, Takalo L, Takami H, Tavecchio F, Temnikov P, Terzic T, Tescaro D, Teshima M, Thaele J, Tibolla O, Torres DF, Toyama T, Treves A, Uellenbeck M, Vogler P, Wagner RM, Zandanel F, Zanin R, DAmmando F, Hovatta T, Larionov VM, Max-Moerbeck W, Perri M, Readhead ACS, Richards JL, Sakamoto T, Schwartz RD, Verrecchia F, and Reyes LC

Subjects
ACTIVE GALACTIC NUCLEI, BL Lacertae objects: individual: MAGIC J2001+439, Galaxies: active, BL Lac objects: individual (MAGIC J2001+435), gamma rays: observations, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, LARGE-AREA TELESCOPE, Nordic Optical Telescope, Spectral line, BL Lacertae objects: individual: MAGIC J2001+435, Gamma rays: galaxies, 0103 physical sciences, GAMMA-RAY SPECTRUM, MAGIC (telescope), 010306 general physics, Blazar, 010303 astronomy & astrophysics, Physics, astro-ph.HE, High Energy Astrophysical Phenomena (astro-ph.HE), galaxies: active – BL Lacertae objects: individual: MAGIC J2001+435 – BL Lacertae objects: individual: MAGIC J2001+439 – gamma rays: galaxies, FERMI ERA, Astronomy and Astrophysics, PKS 1424+240, BL-LACERTAE OBJECTS, Galaxy, Redshift, EXTRAGALACTIC BACKGROUND LIGHT, LAC OBJECTS, SKY SURVEY, RADIATION, Amplitude, Space and Planetary Science, ddc:520, Electrónica, Física nuclear, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, BL Lac object
Abstract

We aim to characterize the broadband emission from 2FGL J2001.1+4352, which has been associated with the unknown-redshift blazar MG4 J200112+4352. Based on its gamma-ray spectral properties, it was identified as a potential very high energy (VHE; E > 100 GeV) gamma-ray emitter. The source was observed with MAGIC first in 2009 and later in 2010 within a multi-instrument observation campaign. The MAGIC observations yielded 14.8 hours of good quality stereoscopic data. The object was monitored at radio, optical and gamma-ray energies during the years 2010 and 2011. The source, named MAGIC J2001+439, is detected for the first time at VHE with MAGIC at a statistical significance of 6.3 {\sigma} (E > 70 GeV) during a 1.3-hour long observation on 2010 July 16. The multi-instrument observations show variability in all energy bands with the highest amplitude of variability in the X-ray and VHE bands. We also organized deep imaging optical observations with the Nordic Optical Telescope in 2013 to determine the source redshift. We determine for the first time the redshift of this BL Lac object through the measurement of its host galaxy during low blazar activity. Using the observational evidence that the luminosities of BL Lac host galaxies are confined to a relatively narrow range, we obtain z = 0.18 +/- 0.04. Additionally, we use the Fermi-LAT and MAGIC gamma-ray spectra to provide an independent redshift estimation, z = 0.17 +/- 0.10. Using the former (more accurate) redshift value, we adequately describe the broadband emission with a one-zone SSC model for different activity states and interpret the few-day timescale variability as produced by changes in the high-energy component of the electron energy distribution., Comment: 17 pages, 15 figures, Accepted for publication in A&A

Published
2014
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45. Discovery of very high energy gamma-ray emission from the blazar 1ES 0033+595 by the MAGIC telescopes

Author

T. Steinbring, A. González Muñoz, Natalia Lewandowska, D. Hildebrand, A. La Barbera, Daniela Dorner, X. Paredes-Fortuny, A. De Angelis, F. Borracci, M. Uellenbeck, Konstancja Satalecka, Michele Doro, S. Partini, S. Buson, Aaron Dominguez, Dario Hrupec, M. A. Lopez, K. Saito, U. Menzel, M. Gaug, J. Becerra González, Mario Meucci, Jelena Aleksić, R. López-Coto, Julian Sitarek, J. Hose, Daniela Hadasch, K. Nishijima, Takashi Saito, A. Niedzwiecki, J. Herrera, T. Toyama, Koji Noda, Giacomo Bonnoli, D. Dominis Prester, Reiko Orito, Diego F. Torres, Thomas Bretz, K. Frantzen, David Paneque, Elisa Bernardini, S. N. Shore, D. Nakajima, G. Maneva, Nikola Godinovic, Benito Marcote, R. Zanin, A. Saggion, P. G. Prada Moroni, M. Garczarczyk, Tihomir Surić, D. Carreto Fidalgo, Martin Makariev, M. I. Martínez, A. Borghese, E. Prandini, Oscar Blanch, O. Tibolla, V. Kadenius, P. Temnikov, Adrian Biland, Francisco Prada, S. Paiano, Lluis Font, Karl Mannheim, M. Hayashida, Victor Stamatescu, J. Krause, A. Herrero, B. De Lotto, J. Rico, Alicia López-Oramas, Stefano Covino, A. Sillanpää, K. Berger, M. Doert, C. Delgado Mendez, V. Tronconi, Hajime Takami, I. Lozano, Nijil Mankuzhiyil, G. De Caneva, S. Bonnefoy, Wolfgang Rhode, Aldo Treves, Sabrina Einecke, S. R. Gozzini, Robert Wagner, J. Rodriguez Garcia, Felix Spanier, W. Idec, P. Munar-Adrover, M. Palatiello, Francesco Dazzi, Masahiro Teshima, S. Sun, Christian Fruck, Daniel Ferenc, D. Tescaro, Yusuke Konno, Silvia Preziuso, Mosè Mariotti, A.-K. Overkemping, P. Da Vela, C. Schultz, V. Scapin, Ivica Puljak, Pierre Colin, Saverio Lombardi, Wlodek Bednarek, Alessandro Carosi, L. Maraschi, Elina Lindfors, E. Colombo, Julia Thaele, Daniel Mazin, Fabio Zandanel, Marc Ribó, L. O. Takalo, P. Bangale, Jose Miguel Miranda, R. Reinthal, Dominik Elsaesser, Hidetoshi Kubo, U. Barres de Almeida, Damir Lelas, R. Mirzoyan, M. V. Fonseca, P. Antoranz, Dorota Sobczyńska, D. Eisenacher, L. A. Antonelli, J. A. Barrio, E. Carmona, Fabrizio Tavecchio, Emanuele Paolo Farina, Nina Nowak, T. Schweizer, S. Rügamer, Tomislav Terzić, Patrick Vogler, I. Snidaric, Hanna Kellermann, K. Mallot, R. J. García López, E. Lorenz, Massimo Persic, J. M. Paredes, Antonio Stamerra, K. Kodani, J. Storz, Stefano Ansoldi, Riccardo Paoletti, J. Kushida, Jose Luis Contreras, Juan Cortina, D. Garrido Terrats, V. Scalzotto, Ana Babić, Kari Nilsson, and Abelardo Moralejo

Subjects
BL Lacertae objects: individual: (1ES 0033+595), Gamma-rays: galaxies, Astronomy and Astrophysics, Space and Planetary Science, Cosmology and Nongalactic Astrophysics (astro-ph.CO), astro-ph.HE, astro-ph.CO, astro-ph.GA, Astrophysics::High Energy Astrophysical Phenomena, Population, FOS: Physical sciences, individual: (1ES 0033 595), gamma-rays: galaxies [BL Lacertae objects], Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, BL Lacertae objects: individual: (1ES 0033 595), 01 natural sciences, Luminosity, 0103 physical sciences, MAGIC (telescope), education, Blazar, 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), education.field_of_study, ta115, 010308 nuclear & particles physics, galaxies: BL Lacertae objects: individual (1ES 0033+595), gamma rays: galaxies, Compton scattering, Astronomy, Astrophysics - Astrophysics of Galaxies, Extragalactic background light, Astrophysics of Galaxies (astro-ph.GA), ddc:520, Spectral energy distribution, Astrophysics - High Energy Astrophysical Phenomena, Fermi Gamma-ray Space Telescope, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Monthly Notices of the Royal Astronomical Society, 446 (1), ISSN:0035-8711, ISSN:1365-2966, ISSN:1365-8711

Published
2014
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46. MAGIC search for vhe γ-ray emission from ae aquarii in a multiwavelength context

Author

D. Nakajima, P. G. Prada Moroni, Laura Maraschi, Yusuke Konno, A. López-Oramas, Alessandro Carosi, Ruben Lopez-Coto, Victor Stamatescu, B. Biasuzzi, Konstancja Satalecka, Michele Doro, D. Dorner, I. Snidaric, Jose Miguel Miranda, M. Bogosavljevic, E. Lorenz, Fabrizio Tavecchio, Hajime Takami, Z. Ioannou, Tomislav Terzić, Ll. Font, A.-K. Overkemping, Elina Lindfors, M. López, Julia Thaele, E. Carmona, Daniel Mazin, A. Treves, K. Nishijima, M. V. Fonseca, Abelardo Moralejo, Patrick Vogler, M. Mariotti, Thomas Bretz, S. Rügamer, Julian Sitarek, Saverio Lombardi, T. Steinbring, Louis Antonelli, Morihiro Hayashida, P. Da Vela, Pierre Colin, K. Nilsson, J. Kushida, D. Hadasch, Dorothee Hildebrand, P. Antoranz, Robert Wagner, G. De Caneva, J. Becerra González, S. Bonnefoy, C. Schultz, X. Paredes-Fortuny, T. Toyama, Dario Hrupec, R. Paoletti, P. Munar-Adrover, Razmik Mirzoyan, M. Palatiello, I. Lozano, M. Strzys, Jose Luis Contreras, Jelena Aleksić, Silvia Preziuso, Damir Lelas, D. Galindo, D. Dominis Prester, R. Zanin, A. Niedzwiecki, A. Saggion, A. De Angelis, A. Sillanpää, Stefano Covino, Dorota Sobczyńska, V. Scapin, Juan Cortina, K. Frantzen, David Paneque, A. Biland, Diego F. Torres, Masahiro Teshima, Christopher W. Mauche, Takashi Saito, E. de Ona Wilhelmi, Y. Hanabata, D. Tescaro, W. Idec, J. M. Paredes, Nikola Godinovic, Benito Marcote, D. Garrido Terrats, R. Reinthal, M. Uellenbeck, Natalia Lewandowska, Reiko Orito, Francesco Dazzi, V. Scalzotto, A. La Barbera, T. Schweizer, Ana Babić, E. V. Palaiologou, Leo O. Takalo, R. J. García López, Antonio Stamerra, Oscar Blanch, Petar Temnikov, Koji Noda, J. Herrera, Elisa Bernardini, H. Kellermann, G. Bonnoli, N. Mankuzhiyil, W. Rhode, Felix Spanier, K. Kodani, C. Delgado Mendez, O. Tibolla, G. Maneva, A. González Muñoz, Christian Fruck, J. Storz, Juan Abel Barrio, I. Puljak, Stefano Ansoldi, D. Eisenacher, Markus Gaug, Markus Garczarczyk, Nina Nowak, D. Elsaesser, J. Hose, B. De Lotto, Elisa Prandini, M. Makariev, W. Bednarek, J. Rico, S. Paiano, U. Menzel, Miguel A. Pérez-Torres, M. I. Martínez, E. Colombo, P. Bangale, V. Kadenius, M. Doert, Sabrina Einecke, S. R. Gozzini, J. Rodriguez Garcia, K. Saito, Marc Ribó, Hidetoshi Kubo, F. Borracci, K. Mallot, T. Tuominen, Massimo Persic, K. Mannheim, J. Krause, and Universitat de Barcelona

Subjects
accretion: accretion disks, Radiation mechanisms: non-thermal, Novae: cataclysmic variables, Gamma rays: stars, Astrofísica, Accretion, Photon, Astrophysics::High Energy Astrophysical Phenomena, Signal region, Cataclysmic variable star, Astrophysics, Noves (Estels), Raigs gamma, Coincident, Accretion, accretion disks, Novae, cataclysmic variables, Astronomy and Astrophysics, Space and Planetary Science, New stars, Novae, Astrophysics::Galaxy Astrophysics, Physics, astro-ph.HE, cataclysmic variables, Spectral index, accretion disks, Gamma rays, Gamma ray, Stars, Estels, Wavelength, 13. Climate action, ddc:520, Electrónica, Física nuclear, Rayleigh test, Electricidad, Astrophysics - High Energy Astrophysical Phenomena
Abstract

It has been claimed that the nova-like cataclysmic variable (CV) AE Aquarii (AE Aqr) is a very-high-energy (VHE, $E>$100 GeV) source both on observational and theoretical grounds. We aim to search for VHE gamma-ray emission from AE Aqr during different states of the source at several wavelengths to confirm or rule out previous claims of detection of gamma-ray emission from this object. We report on observations of AE Aqr performed by MAGIC. The source was observed during 12 hours as part of a multiwavelength campaign carried out between May and June 2012 covering the optical, X-ray, and gamma-ray ranges. Besides MAGIC, the other facilities involved were the KVA, Skinakas, and Vidojevica telescopes in the optical and Swift in X-rays. We calculated integral upper limits coincident with different states of the source in the optical. We computed upper limits to the pulsed emission limiting the signal region to 30% of the phaseogram and we also searched for pulsed emission at different frequencies applying the Rayleigh test. AE Aqr was not detected at VHE energies during the multiwavelength campaign. We establish integral upper limits at the 95\% confidence level for the steady emission assuming the differential flux proportional to a power-law function d\phi/dE \propto E^{-Gamma}, with a Crab-like photon spectral index of Gamma=2.6. The upper limit above 200 GeV is 6.4\times10^{-12} cm^{-2}s^{-1} and above 1 TeV is 7.4\times10^{-13} cm^{-2}s^{-1}. We obtained an upper limit for the pulsed emission of 2.6\times10^{-12} cm^{-2}s^{-1} for energies above 200 GeV. Applying the Rayleigh test for pulsed emission at different frequencies we did not find any significant signal. Our results indicate that AE Aqr is not a VHE gamma-ray emitter at the level of emission previously claimed. We have established the most constraining upper limits for the VHE gamma-ray emission of AE Aqr., Comment: 9 pages, 5 figures. Accepted for publication in A&A

Published
2014
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47. Discovery of very high energy gamma-ray emission from the blazar 1ES 1727+502 with the MAGIC Telescopes

Author

Nina Nowak, Abelardo Moralejo, D. Häfner, L. A. Antonelli, W. Idec, J. Masbou, M. I. Martínez, J. M. Paredes, Antonio Stamerra, M. Salvati, Dario Hrupec, Thomas Bretz, V. Kadenius, S. Rügamer, Mosè Mariotti, Marc Ribó, M. A. Lopez, Fabrizio Tavecchio, S. N. Shore, Juan Abel Barrio, D. Borla Tridon, Dominik Elsaesser, U. Barres de Almeida, S. Bonnefoy, K. Berger, Ll. Font, A. Hadamek, M. Doert, Emanuele Paolo Farina, Aaron Dominguez, J. Storz, G. De Caneva, Damir Lelas, R. Mirzoyan, Michael Backes, A. De Angelis, Christian Fruck, D. Eisenacher, J. Becerra González, Saverio Lombardi, T. Krähenbühl, M. L. Knoetig, Ignasi Reichardt, P. G. Prada Moroni, E. Carmona, I. Snidaric, Markus Garczarczyk, Nijil Mankuzhiyil, P. Munar-Adrover, Wolfgang Rhode, O. Tibolla, Dorota Sobczyńska, Kari Nilsson, M. V. Fonseca, Mario Meucci, Felix Spanier, M. Palatiello, E. Colombo, G. Maneva, Daniel Ferenc, A. Boller, L. Cossio, R. Zanin, A. Saggion, Ralph Bock, Nikola Godinovic, Benito Marcote, K. Mallot, R. J. García López, S. Spiro, E. Lorenz, Adrian Biland, Francesco Dazzi, L. O. Takalo, B. Steinke, Riccardo Paoletti, S. Partini, D. Dominis Prester, Artemio Herrero, J. Rico, K. Saito, J. Kushida, Jose Luis Contreras, Tomislav Terzić, J. Moldón, Francisco Prada, Juan Cortina, Hajime Takami, Ivica Puljak, Massimo Persic, Pierre Colin, R. Reinthal, Giacomo Bonnoli, Patrick Vogler, J. Krause, B. De Lotto, Martin Makariev, M. Asensio, Oscar Blanch, D. Garrido Terrats, A. Sillanpää, V. Scalzotto, Takashi Saito, Q. Weitzel, Tihomir Surić, Reiko Orito, C. Schultz, V. Scapin, D. Carreto Fidalgo, E. Prandini, Aldo Treves, S. Klepser, S. Paiano, C. Delgado Mendez, S. R. Gozzini, Karl Mannheim, Gianluca Giavitto, A. González Muñoz, Daniela Dorner, M. Gaug, Diego F. Torres, Elisa Bernardini, Natalia Lewandowska, F. Jankowski, F. Borracci, A. La Barbera, A. López-Oramas, Wlodek Bednarek, Alessandro Carosi, Ruben Lopez-Coto, D. Nakajima, Jose Miguel Miranda, P. Antoranz, L. Maraschi, M. Uellenbeck, Elina Lindfors, Konstancja Satalecka, Daniel Mazin, Michele Doro, P. Temnikov, Fabio Zandanel, Shan Sun, Jelena Aleksić, I. Lozano, D. Hadasch, Masahiro Teshima, A. Niedzwiecki, T. Schweizer, Stefano Covino, David Paneque, D. Tescaro, Robert Wagner, Victor Stamatescu, Julian Sitarek, J. Hose, T. Toyama, P. Da Vela, and Universitat de Barcelona

Subjects
Astrofísica, Swift Gamma-Ray Burst Mission, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, 7. Clean energy, law.invention, Telescope, Raigs gamma, law, 0103 physical sciences, MAGIC (telescope), Nucli galàctic actiu, Blazar, 010303 astronomy & astrophysics, BL Lac objects: individual(1ES 1727+502), galaxies: active, gamma rays, Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), astro-ph.HE, Active galactic nuclei, Telescopis, 010308 nuclear & particles physics, Gamma rays, Gamma ray, Astronomy and Astrophysics, Galaxies: active, Space and Planetary Science, Galaxies, Galàxies, Crab Nebula, 13. Climate action, ddc:520, Spectral energy distribution, Electrónica, Física nuclear, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, BL Lac object, Telescopes
Abstract

Motivated by the Costamante & Ghisellini (2002) predictions we investigated if the blazar 1ES 1727+502 (z=0.055) is emitting very high energy (VHE, E>100 GeV) gamma rays. We observed the BL Lac object 1ES 1727+502 in stereoscopic mode with the two MAGIC telescopes during 14 nights between May 6th and June 10th 2011, for a total effective observing time of 12.6 hours. For the study of the multiwavelength spectral energy distribution (SED) we use simultaneous optical R-band data from the KVA telescope, archival UV/optical and X-ray observations by instruments UVOT and XRT on board of the Swift satellite and high energy (HE, 0.1 GeV - 100 GeV) gamma-ray data from the Fermi-LAT instrument. We detect, for the first time, VHE gamma-ray emission from 1ES 1727+502 at a statistical significance of 5.5 sigma. The integral flux above 150 GeV is estimated to be (2.1\pm0.4)% of the Crab Nebula flux and the de-absorbed VHE spectrum has a photon index of (2.7\pm0.5). No significant short-term variability was found in any of the wavebands presented here. We model the SED using a one-zone synchrotron self-Compton model obtaining parameters typical for this class of sources., 7 pages, 5 figures, 2 tables, submitted to A&A

Published
2014
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48. Optimized dark matter searches in deep observations of Segue 1 with MAGIC

Author

M. V. Fonseca, L. Maraschi, M. Palatiello, Daniel Ferenc, Antonio Stamerra, Christian Fruck, Juan Abel Barrio, I. Puljak, J. Kushida, K. Kodani, Mosè Mariotti, Abelardo Moralejo, A.-K. Overkemping, Stefano Covino, Jose Luis Contreras, Oscar Blanch, Tomislav Terzić, Francesco Dazzi, Daniela Dorner, Juan Cortina, T. Steinbring, J. Storz, R. J. García López, Fabio Zandanel, G. Bonnoli, Shan Sun, Nikola Godinovic, Benito Marcote, R. Zanin, P. Da Vela, Robert Wagner, D. Hadasch, A. Saggion, Tihomir Surić, D. Carreto Fidalgo, Jelena Aleksić, D. Tescaro, A. Niedzwiecki, Adrian Biland, David Paneque, B. De Lotto, Saverio Lombardi, D. Garrido Terrats, K. Frantzen, Nijil Mankuzhiyil, X. Paredes-Fortuny, D. Dominis Prester, Damir Lelas, D. Nakajima, Louis Antonelli, Elina Lindfors, Karl Mannheim, P. Munar-Adrover, P. G. Prada Moroni, Daniel Mazin, A. De Angelis, V. Scalzotto, Stefano Ansoldi, Konstancja Satalecka, Silvia Preziuso, Riccardo Paoletti, Markus Gaug, S. Rügamer, Michele Doro, C. Schultz, V. Scapin, Dario Hrupec, Aaron Dominguez, Marc Ribó, A. López-Oramas, M. Uellenbeck, Dorothee Hildebrand, Ana Babić, G. De Caneva, R. Reinthal, Alessandro Carosi, P. Antoranz, Hidetoshi Kubo, S. Bonnefoy, Ruben Lopez-Coto, J. Becerra González, Petar Temnikov, J. M. Paredes, J. Hose, Diego F. Torres, Jose Miguel Miranda, Kari Nilsson, M. López, Dorota Sobczyńska, Elisa Bernardini, D. Elsaesser, T. Schweizer, H. Kellermann, Yusuke Konno, O. Tibolla, U. Barres de Almeida, Mario Meucci, K. Berger, I. Lozano, M. Salvati, F. Borracci, W. Idec, R. K. Bock, Emanuele Paolo Farina, A. Sillanpää, M. Doert, Takashi Saito, Masahiro Teshima, Alejandro Ibarra, E. Colombo, Hajime Takami, Reiko Orito, G. Maneva, C. Delgado Mendez, Felix Spanier, Natalia Lewandowska, K. Saito, Julian Sitarek, Pierre Colin, Julia Thaele, Aldo Treves, L. O. Takalo, A. La Barbera, E. Carmona, M. I. Martínez, Kazuyoshi Nishijima, M. Hayashida, P. Bangale, Gianluca Giavitto, A. González Muñoz, V. Kadenius, Sabrina Einecke, S. R. Gozzini, Francisco Prada, J. Rodriguez Garcia, M. Makariev, J. Rico, Victor Stamatescu, U. Menzel, Simona Paiano, Thomas Bretz, R. Mirzoyan, Wolfgang Rhode, J. Krause, K. Mallot, Massimo Persic, Takeshi Toyama, I. Snidaric, D. Eisenacher, Markus Garczarczyk, Nina Nowak, E. Lorenz, W. Bednarek, Fabrizio Tavecchio, Ll. Font, Elisa Prandini, Patrick Vogler, A. Herrero, S. Partini, Universitat de Barcelona, and SCOAP

Subjects
Astrofísica, Particle physics, Electromagnetic spectrum, Astrophysics::High Energy Astrophysical Phenomena, Dark matter, dark matter, indirect searches, gamma-ray experiments, Imaging Air Cherenkov Telescopes, dwarf spheroidal galaxies, Segue 1, Gamma ray experiments, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, Gamma ray astronomy, Satellite galaxy, Astronomia de raigs gamma, ddc:530, 010306 general physics, Dwarf galaxies, Dwarf galaxy, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Annihilation, Telescopis, 010308 nuclear & particles physics, Bremsstrahlung, Astronomy and Astrophysics, Segue, Galaxies, dwarfs galaxies, Galàxies, High Energy Physics - Phenomenology, Dark matter experiments, Dark matter (Astronomy), dark matter experiments, gamma ray experiments, Monochromatic color, Matèria fosca (Astronomia), Astrophysics - High Energy Astrophysical Phenomena, Telescopes
Abstract

Aleksic, J. et al., We present the results of stereoscopic observations of the satellite galaxy Segue 1 with the MAGIC Telescopes, carried out between 2011 and 2013. With almost 160 hours of good-quality data, this is the deepest observational campaign on any dwarf galaxy performed so far in the very high energy range of the electromagnetic spectrum. We search this large data sample for signals of dark matter particles in the mass range between 100 GeV and 20 TeV. For this we use the full likelihood analysis method, which provides optimal sensitivity to characteristic gamma-ray spectral features, like those expected from dark matter annihilation or decay. In particular, we focus our search on gamma-rays produced from different final state Standard Model particles, annihilation with internal bremsstrahlung, monochromatic lines and box-shaped signals. Our results represent the most stringent constraints to the annihilation cross-section or decay lifetime obtained from observations of satellite galaxies, for masses above few hundred GeV. In particular, our strongest limit (95% confidence level) corresponds to a ~ 500 GeV dark matter particle annihilating into τ+τ−, and is of order langleσannvrangle simeq 1.2 × 10−24 cm3 s−1 — a factor ~ 40 above the langleσannvrangle simeq thermal value., The support of the German BMBF and MPG, the Italian INFN, the Swiss National Fund SNF, and the Spanish MICINN is gratefully acknowledged. This work was also supported by the CPAN CSD2007-00042 and MultiDark CSD2009-00064 projects of the Spanish Consolider- Ingenio 2010 programme, by grant 127740 of the Academy of Finland, by the DFG Cluster of Excellence “Origin and Structure of the Universe”, by the Croatian Science Foundation Project 09/176, by the DFG Collaborative Research Centers SFB823/C4 and SFB876/C3, and by the Polish MNiSzW grant 745/N-HESS-MAGIC/2010/0.

Published
2014
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49. MAGIC long-term study of the distant TeV blazar PKS 1424+240 in a multiwavelength context

Author

Aaron Dominguez, Mosè Mariotti, A.-K. Overkemping, P. G. Prada Moroni, C. Schultz, V. Scapin, Anthony C. S. Readhead, A. González Muñoz, Hajime Takami, O. Tibolla, A. De Angelis, A. Treves, Saverio Lombardi, Daniela Dorner, Daniel Ferenc, S. Rügamer, Juan Abel Barrio, M. Gaug, J. Herrera, Koji Noda, Hanna Kellermann, Elisa Bernardini, G. Maneva, R. Zanin, A. Saggion, S. Partini, Antonio Stamerra, S. N. Shore, K. Kodani, Adrian Biland, Victor Stamatescu, C. Delgado Mendez, J. Rico, P. Temnikov, Stefano Covino, J. Storz, Nina Nowak, Fabio Zandanel, Nikola Godinovic, Benito Marcote, S. Sun, Jari Kotilainen, Julian Sitarek, S. Bonnefoy, D. Tescaro, C. Fruck, T. Toyama, M. Palatiello, Dario Gasparrini, D. Eisenacher, T. Schweizer, Stefano Ansoldi, M. Uellenbeck, Francesco Dazzi, Riccardo Paoletti, E. Carmona, Markus Garczarczyk, A. K. Furniss, Oscar Blanch, J. L. Richards, Elina Lindfors, K. Mallot, Daniel Mazin, R. J. García López, Matthew L. Lister, Konstancja Satalecka, E. Prandini, Michele Doro, Talvikki Hovatta, G. De Caneva, G. Bonnoli, M. Doert, Massimo Persic, P. Da Vela, Ivica Puljak, Pierre Colin, M. Makariev, D. Nakajima, Robert Wagner, R. Reinthal, Razmik Mirzoyan, U. Barres de Almeida, U. Menzel, Jelena Aleksić, Damir Lelas, I. Lozano, D. Hildebrand, W. Idec, M. V. Fonseca, A. Niedzwiecki, Vasiliki Pavlidou, Dorota Sobczyńska, David Paneque, Anne Lähteenmäki, A. Sillanpää, Masahiro Teshima, K. Nishijima, K. Saito, Tuomas Kangas, Takashi Saito, Dario Hrupec, D. Dominis Prester, D. Hadasch, M. I. Martínez, P. Bangale, Francisco Prada, Reiko Orito, Sabrina Einecke, S. R. Gozzini, J. Rodriguez Garcia, E. Colombo, Louis Antonelli, Felix Spanier, L. O. Takalo, Nijil Mankuzhiyil, X. Paredes-Fortuny, P. Munar-Adrover, Silvia Preziuso, M. A. Lopez, P. Antoranz, Natalia Lewandowska, A. La Barbera, Yusuke Konno, Julia Thaele, J. Becerra González, Mario Meucci, K. Frantzen, Tihomir Surić, D. Carreto Fidalgo, J. M. Paredes, V. Kadenius, S. Paiano, Karl Mannheim, M. Hayashida, Alicia López-Oramas, J. Krause, B. De Lotto, Marc Ribó, Diego F. Torres, Hidetoshi Kubo, Abelardo Moralejo, J. Hose, T. Steinbring, D. Elsaesser, A. Herrero, Emanuele Paolo Farina, S. Cutini, Kari Nilsson, Thomas Bretz, J. Kushida, Jose Luis Contreras, Juan Cortina, F. Borracci, D. Garrido Terrats, V. Scalzotto, Ana Babić, Walter Max-Moerbeck, Wolfgang Rhode, Alessandro Carosi, Ruben Lopez-Coto, Jose Miguel Miranda, W. Bednarek, Fabrizio Tavecchio, Ll. Font, I. Snidaric, E. Lorenz, Patrick Vogler, Erkki Kankare, L. Maraschi, Tomislav Terzić, Universitat de Barcelona, Metsähovi Radio Observatory, Department of Radio Science and Engineering, Aalto-yliopisto, Aalto University, and Anne Lähteenmäki Group

Subjects
Astrofísica, PARTICLE-ACCELERATION, Astrophysics, 7. Clean energy, LARGE-AREA TELESCOPE, Spectral line, Raigs gamma, Gamma rays: galaxies, Astronomy and Astrophysics, Space and Planetary Science, MAGIC (telescope), High Energy Astrophysical Phenomena (astro-ph.HE), Physics, astro-ph.HE, 213 Electronic, automation and communications engineering, electronics, BL-LACERTAE OBJECTS, EXTRAGALACTIC BACKGROUND LIGHT, GAMMA-RAY EMISSION, SPECTRAL ENERGY-DISTRIBUTION, ACTIVE GALACTIC NUCLEI, LAC OBJECTS, X-RAY, FERMI OBSERVATIONS, Gamma ray, Extragalactic background light, galaxies [gamma rays], astro-ph.CO, Spectral energy distribution, Electrónica, Física nuclear, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics, 1171 Geosciences, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics::High Energy Astrophysical Phenomena, education, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, gamma rays: observations, blazar, BL Lac: AGNs: individual (PKS 1424+240), 114 Physical sciences, Nucli galàctic actiu, Blazar, Active galactic nuclei, Telescopis, 221 Nanotechnology, Gamma rays, Light curve, Redshift, individual: PKS 1424+240 [BL Lacertae objects], 115 Astronomy and space science, 216 Materials engineering, ddc:520, Telescopes
Abstract

We present a study of the very high energy (VHE; E > 100 GeV) gamma-ray emission of the blazar PKS 1424+240 observed with the MAGIC telescopes. The primary aim of this paper is the multiwavelength spectral characterization and modeling of this blazar, which is made particularly interesting by the recent discovery of a lower limit of its redshift of z > 0.6 and makes it a promising candidate to be the most distant VHE source. The source has been observed with the MAGIC telescopes in VHE gamma rays for a total observation time of ~33.6 h from 2009 to 2011. The source was marginally detected in VHE gamma rays during 2009 and 2010, and later, the detection was confirmed during an optical outburst in 2011. The combined significance of the stacked sample is ~7.2 sigma. The differential spectra measured during the different campaigns can be described by steep power laws with the indices ranging from 3.5 +/- 1.2 to 5.0 +/- 1.7. The MAGIC spectra corrected for the absorption due to the extragalactic background light connect smoothly, within systematic errors, with the mean spectrum in 2009-2011 observed at lower energies by the Fermi-LAT. The absorption-corrected MAGIC spectrum is flat with no apparent turn down up to 400 GeV. The multiwavelength light curve shows increasing flux in radio and optical bands that could point to a common origin from the same region of the jet. The large separation between the two peaks of the constructed non-simultaneous spectral energy distribution also requires an extremely high Doppler factor if an one zone synchrotron self-Compton model is applied. We find that a two-component synchrotron self-Compton model describes the spectral energy distribution of the source well, if the source is located at z~0.6., 15 pages, 8 figures. A&A accepted for publication

Published
2014
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50. Detection of bridge emission above 50 GeV from the Crab pulsar with the MAGIC telescopes

Author

P. G. Prada Moroni, W. Bednarek, Pierre Colin, Diego F. Torres, D. Nakajima, Fabrizio Tavecchio, Stefano Covino, Ll. Font, Konstancja Satalecka, Michele Doro, Kouichi Hirotani, Nijil Mankuzhiyil, X. Paredes-Fortuny, Dario Hrupec, R. Zanin, A. Saggion, Adrian Biland, Kazuo Saito, P. Munar-Adrover, A. Treves, R. Reinthal, Shan Sun, A. Sillanpää, Antonio Stamerra, Silvia Preziuso, M. A. Lopez, Marc Ribó, Thomas Bretz, S. N. Shore, G. Maneva, Jelena Aleksić, Takashi Saito, A. Niedzwiecki, Abelardo Moralejo, J. Kushida, Jose Luis Contreras, J. M. Paredes, Hidetoshi Kubo, Reiko Orito, Natalia Lewandowska, U. Barres de Almeida, T. Steinbring, M. Makariev, A. Herrero, I. Puljak, M. V. Fonseca, E. Lorenz, M. Uellenbeck, D. Hadasch, J. Storz, Juan Cortina, D. Paneque, G. De Caneva, A. La Barbera, J. Rico, Christian Fruck, Elina Lindfors, S. Partini, Yusuke Konno, Emanuele Paolo Farina, U. Menzel, S. Bonnefoy, M. Doert, Daniel Mazin, Simona Paiano, B. Biasuzzi, Patrick Vogler, Daniel Ferenc, Elisa Prandini, P. Da Vela, T. Schweizer, Razmik Mirzoyan, S. Rügamer, B. De Lotto, L. Maraschi, Robert Wagner, J. Krause, I. Lozano, J. Becerra González, S. Ansoldi, Damir Lelas, M. I. Martínez, P. Bangale, V. Kadenius, Tomislav Terzić, D. Tescaro, G. Bonnoli, Hajime Takami, C. Delgado Mendez, Dorota Sobczyńska, Sabrina Einecke, Oscar Blanch, M. Hayashida, S. R. Gozzini, R. J. García López, N. Nowak, Kari Nilsson, Masahiro Teshima, Juan Abel Barrio, J. Rodriguez Garcia, Riccardo Paoletti, Markus Gaug, Nikola Godinovic, Benito Marcote, J. Hose, D. Garrido Terrats, Daniela Dorner, Takeshi Toyama, K. Mallot, W. Rhode, V. Scalzotto, D. Eisenacher, I. Šnidarić, K. Frantzen, M. Palatiello, Markus Garczarczyk, D. Elsaesser, Massimo Persic, Ana Babić, Petar Temnikov, Koji Noda, Elisa Bernardini, H. Kellermann, A. González Muñoz, C. Schultz, V. Scapin, Jose Carlos Herrera, Francesco Dazzi, A. López-Oramas, Karl Mannheim, Alessandro Carosi, Ruben Lopez-Coto, Jose Miguel Miranda, F. Borracci, T. Surić, Julia Thaele, E. Carmona, D. Fidalgo, Dorothee Hildebrand, P. Antoranz, M. Strzys, Julian Sitarek, Victor Stamatescu, Felix Spanier, K. Nishijima, D. Dominis Prester, Omar Tibolla, Louis Antonelli, A. De Angelis, K. Kodani, W. Idec, Mosè Mariotti, A.-K. Overkemping, Saverio Lombardi, E. Colombo, L. O. Takalo, and Universitat de Barcelona

Subjects
Astrofísica, Spectral shape analysis, Astrophysics::High Energy Astrophysical Phenomena, Theoretical models, FOS: Physical sciences, Gamma rays: stars, Pulsars: individual: Crab pulsar, Stars: neutron, Astronomy and Astrophysics, Space and Planetary Science, Astrophysics, Spectral line, Raigs gamma, MAGIC (telescope), Connection (algebraic framework), pulsars: individual: Crab pulsar, gamma rays: stars, Pulsars, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Telescopis, Crab Pulsar, Gamma rays, Light curve, Stars, Púlsars, Estels, ddc:520, Electrónica, Física nuclear, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, Telescopes, Fermi Gamma-ray Space Telescope
Abstract

The Crab pulsar is the only astronomical pulsed source detected at very high energy (VHE, E>100GeV) gamma-rays. The emission mechanism of VHE pulsation is not yet fully understood, although several theoretical models have been proposed. In order to test the new models, we measured the light curve and the spectra of the Crab pulsar with high precision by means of deep observations. We analyzed 135 hours of selected MAGIC data taken between 2009 and 2013 in stereoscopic mode. In order to discuss the spectral shape in connection with lower energies, 4.6 years of {\it Fermi}-LAT data were also analyzed. The known two pulses per period were detected with a significance of $8.0 \sigma$ and $12.6 \sigma$. In addition, significant emission was found between the two pulses with $6.2 \sigma$. We discovered the bridge emission above 50 GeV between the two main pulses. This emission can not be explained with the existing theories. These data can be used for testing new theoretical models., Comment: 5 pages, 4 figures

Published
2014
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