136 results on '"Alessandro Paggi"'
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2. Detection of X-Ray Polarization from the Blazar 1ES 1959+650 with the Imaging X-Ray Polarimetry Explorer
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Manel Errando, Ioannis Liodakis, Alan P. Marscher, Herman L. Marshall, Riccardo Middei, Michela Negro, Abel Lawrence Peirson, Matteo Perri, Simonetta Puccetti, Pazit L. Rabinowitz, Iván Agudo, Svetlana G. Jorstad, Sergey S. Savchenko, Dmitry Blinov, Ioakeim G. Bourbah, Sebastian Kiehlmann, Evangelos Kontopodis, Nikos Mandarakas, Stylianos Romanopoulos, Raphael Skalidis, Anna Vervelaki, Francisco José Aceituno, Maria I. Bernardos, Giacomo Bonnoli, Víctor Casanova, Beatriz Agís-González, César Husillos, Alessandro Marchini, Alfredo Sota, Pouya M. Kouch, Elina Lindfors, Carolina Casadio, Juan Escudero, Ioannis Myserlis, Ryo Imazawa, Mahito Sasada, Yasushi Fukazawa, Koji S. Kawabata, Makoto Uemura, Tsunefumi Mizuno, Tatsuya Nakaoka, Hiroshi Akitaya, Mark Gurwell, Garrett K. Keating, Ramprasad Rao, Adam Ingram, Francesco Massaro, Lucio Angelo Antonelli, Raffaella Bonino, Elisabetta Cavazzuti, Chien-Ting Chen, Nicolò Cibrario, Stefano Ciprini, Alessandra De Rosa, Laura Di Gesu, Federico Di Pierro, Immacolata Donnarumma, Steven R. Ehlert, Francesco Fenu, Ephraim Gau, Vladimir Karas, Dawoon E. Kim, Henric Krawczynski, Marco Laurenti, Lindsey Lisalda, Rubén López-Coto, Grzegorz Madejski, Frédéric Marin, Andrea Marinucci, Ikuyuki Mitsuishi, Fabio Muleri, Luigi Pacciani, Alessandro Paggi, Pierre-Olivier Petrucci, Nicole Rodriguez Cavero, Roger W. Romani, Fabrizio Tavecchio, Stefano Tugliani, Kinwah Wu, Matteo Bachetti, Luca Baldini, Wayne H. Baumgartner, Ronaldo Bellazzini, Stefano Bianchi, Stephen D. Bongiorno, Alessandro Brez, Niccolò Bucciantini, Fiamma Capitanio, Simone Castellano, Enrico Costa, Ettore Del Monte, Niccolò Di Lalla, Alessandro Di Marco, Victor Doroshenko, Michal Dovčiak, Teruaki Enoto, Yuri Evangelista, Sergio Fabiani, Riccardo Ferrazzoli, Javier A. Garcia, Shuichi Gunji, Kiyoshi Hayashida, Jeremy Heyl, Wataru Iwakiri, Philip Kaaret, Fabian Kislat, Takao Kitaguchi, Jeffery J. Kolodziejczak, Fabio La Monaca, Luca Latronico, Simone Maldera, Alberto Manfreda, Giorgio Matt, C.-Y. Ng, Stephen L. O’Dell, Nicola Omodei, Chiara Oppedisano, Alessandro Papitto, George G. Pavlov, Melissa Pesce-Rollins, Maura Pilia, Andrea Possenti, Juri Poutanen, Brian D. Ramsey, John Rankin, Ajay Ratheesh, Oliver J. Roberts, Carmelo Sgrò, Patrick Slane, Paolo Soffitta, Gloria Spandre, Douglas A. Swartz, Toru Tamagawa, Roberto Taverna, Yuzuru Tawara, Allyn F. Tennant, Nicholas E. Thomas, Francesco Tombesi, Alessio Trois, Sergey S. Tsygankov, Roberto Turolla, Jacco Vink, Martin C. Weisskopf, Fei Xie, and Silvia Zane
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Relativistic jets ,X-ray active galactic nuclei ,Active galactic nuclei ,Blazars ,Polarimetry ,Spectropolarimetry ,Astrophysics ,QB460-466 - Abstract
Observations of linear polarization in the 2–8 keV energy range with the Imaging X-ray Polarimetry Explorer (IXPE) explore the magnetic field geometry and dynamics of the regions generating nonthermal radiation in relativistic jets of blazars. These jets, particularly in blazars whose spectral energy distribution peaks at X-ray energies, emit X-rays via synchrotron radiation from high-energy particles within the jet. IXPE observations of the X-ray-selected BL Lac–type blazar 1ES 1959+650 on 2022 May 3–4 showed a significant linear polarization degree of Π _x = 8.0% ± 2.3% at an electric-vector position angle ψ _x = 123° ± 8°. However, on 2022 June 9–12, only an upper limit of Π _x ≤ 5.1% could be derived (at the 99% confidence level). The degree of optical polarization at that time, Π _O ∼ 5%, is comparable to the X-ray measurement. We investigate possible scenarios for these findings, including temporal and geometrical depolarization effects. Unlike some other X-ray-selected BL Lac objects, there is no significant chromatic dependence of the measured polarization in 1ES 1959+650, and its low X-ray polarization may be attributed to turbulence in the jet flow with dynamical timescales shorter than 1 day.
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- 2024
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3. The IXPE View of GRB 221009A
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Michela Negro, Niccolò Di Lalla, Nicola Omodei, Péter Veres, Stefano Silvestri, Alberto Manfreda, Eric Burns, Luca Baldini, Enrico Costa, Steven R. Ehlert, Jamie A. Kennea, Ioannis Liodakis, Herman L. Marshall, Sandro Mereghetti, Riccardo Middei, Fabio Muleri, Stephen L. O’Dell, Oliver J. Roberts, Roger W. Romani, Carmelo Sgró, Masanobu Terashima, Andrea Tiengo, Domenico Viscolo, Alessandro Di Marco, Fabio La Monaca, Luca Latronico, Giorgio Matt, Matteo Perri, Simonetta Puccetti, Juri Poutanen, Ajay Ratheesh, Daniele Rogantini, Patrick Slane, Paolo Soffitta, Elina Lindfors, Kari Nilsson, Anni Kasikov, Alan P. Marscher, Fabrizio Tavecchio, Nicoló Cibrario, Shuichi Gunji, Christian Malacaria, Alessandro Paggi, Yi-Jung Yang, Silvia Zane, Martin C. Weisskopf, Iván Agudo, Lucio A. Antonelli, Matteo Bachetti, Wayne H. Baumgartner, Ronaldo Bellazzini, Stefano Bianchi, Stephen D. Bongiorno, Raffaella Bonino, Alessandro Brez, Niccolò Bucciantini, Fiamma Capitanio, Simone Castellano, Elisabetta Cavazzuti, Chien-Ting Chen, Stefano Ciprini, Alessandra De Rosa, Ettore Del Monte, Laura Di Gesu, Immacolata Donnarumma, Victor Doroshenko, Michal Dovc̆iak, Teruaki Enoto, Yuri Evangelista, Sergio Fabiani, Riccardo Ferrazzoli, Javier A. Garcia, Kiyoshi Hayashida, Jeremy Heyl, Wataru Iwakiri, Svetlana G. Jorstad, Philip Kaaret, Vladimir Karas, Fabian Kislat, Takao Kitaguchi, Jeffery J. Kolodziejczak, Henric Krawczynski, Simone Maldera, Frédéric Marin, Andrea Marinucci, Ikuyuki Mitsuishi, Tsunefumi Mizuno, C.-Y. Ng, Chiara Oppedisano, Alessandro Papitto, George G. Pavlov, Abel L. Peirson, Melissa Pesce-Rollins, Pierre-Olivier Petrucci, Maura Pilia, Andrea Possenti, Brian D. Ramsey, John Rankin, Gloria Spandre, Douglas A. Swartz, Toru Tamagawa, Roberto Taverna, Yuzuru Tawara, Allyn F. Tennant, Nicholas E. Thomas, Francesco Tombesi, Alessio Trois, Sergey S. Tsygankov, Roberto Turolla, Jacco Vink, Kinwah Wu, and Fei Xie
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Gamma-ray bursts ,Polarimetry ,X-ray astronomy ,Astrophysics ,QB460-466 - Abstract
We present the IXPE observation of GRB 221009A, which includes upper limits on the linear polarization degree of both prompt and afterglow emission in the soft X-ray energy band. GRB 221009A is an exceptionally bright gamma-ray burst (GRB) that reached Earth on 2022 October 9 after traveling through the dust of the Milky Way. The Imaging X-ray Polarimetry Explorer (IXPE) pointed at GRB 221009A on October 11 to observe, for the first time, the 2–8 keV X-ray polarization of a GRB afterglow. We set an upper limit to the polarization degree of the afterglow emission of 13.8% at a 99% confidence level. This result provides constraints on the jet opening angle and the viewing angle of the GRB, or alternatively, other properties of the emission region. Additionally, IXPE captured halo-rings of dust-scattered photons that are echoes of the GRB prompt emission. The 99% confidence level upper limit to the prompt polarization degree depends on the background model assumption, and it ranges between ∼55% and ∼82%. This single IXPE pointing provides both the first assessment of X-ray polarization of a GRB afterglow and the first GRB study with polarization observations of both the prompt and afterglow phases.
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- 2023
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4. Optical Spectroscopic Observations of Gamma-Ray Blazar Candidates. XII. Follow-up Observations from SOAR, Blanco, NTT, and OAN-SPM
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Abigail García-Pérez, Harold A. Peña-Herazo, Francesco Massaro, Vahram Chavushyan, Raffaele D’abrusco, Nicola Masetti, Marco Landoni, Fabio La Franca, Víctor M. Patiño-Álvarez, Raúl A. Amaya-Almazán, Dan Milisavljevic, Alessandro Paggi, Federica Ricci, Elena Jiménez-Bailón, and Howard A. Smith
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Optical identification ,Blazars ,BL Lacertae objects ,Flat-spectrum radio quasars ,Astronomy ,QB1-991 - Abstract
Roughly one third of the sources in the Fermi-LAT catalogs are listed as unidentified/unassociated γ -ray sources (UGS), i.e., they lack a low-energy counterpart. In addition, there is a growing population of blazars of uncertain type (BCUs). Spectroscopic observations are crucial to confirm the blazar nature of the UGSs candidate counterparts and BCUs. Hence, in 2013 we started an optical spectroscopic campaign to carry out the identifications and classifications. In this paper, as a continuation of the campaign we report the spectra of 39 sources: the sample comprises 37 sources classified as BCUs, one source classified as a BL Lac in the Fourth Source Catalog of the Fermi-LAT (4FGL), and one source classified as UGS. We classify 19 of the sources in the sample as BL Lacs, 13 as blazars with nonnegligible host-galaxy emission, six as Flat Spectrum Radio Quasars, and one as a normal elliptical galaxy. The source listed as BL Lac in the 4FGL seems to be a blazar with nonnegligible host-galaxy emission in our observations, most likely due to an ongoing quiescent state. We classified the UGS source as a BL Lac. Six out of the 39 sources were previously reported in the campaign; in general, both the classifications and redshifts are in agreement, except for one of them with no redshift reported before. Altogether, we provided reliable redshift estimates to 21 out of the 39 sources. Finally, we describe the statistics of the data collected in our campaign so far.
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- 2023
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5. Powerful Yet Lonely: Is 3C 297 a High-redshift Fossil Group?
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Valentina Missaglia, Juan P. Madrid, Mischa Schirmer, Francesco Massaro, Alberto Rodríguez-Ardila, Carlos J. Donzelli, Martell Valencia, Alessandro Paggi, Ralph P. Kraft, Chiara Stuardi, and Belinda J. Wilkes
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Active galactic nuclei ,Brightest cluster galaxies ,Galaxy clusters ,Intracluster medium ,Astrophysics ,QB460-466 - Abstract
The environment of the high-redshift ( z = 1.408), powerful radio-loud galaxy 3C 297 has several distinctive features of a galaxy cluster. Among them, a characteristic halo of hot gas revealed by Chandra X-ray observations. In addition, a radio map obtained with the Very Large Array shows a bright hotspot in the northwestern direction, created by the interaction of the active galactic nucleus (AGN) jet arising from 3C 297 with its environment. In the X-ray images, emission cospatial with the northwestern radio lobe is detected, and peaks at the position of the radio hotspot. The extended, complex X-ray emission observed with our new Chandra data is largely unrelated to its radio structure. Despite having attributes of a galaxy cluster, no companion galaxies have been identified from 39 new spectra of neighboring targets of 3C 297 obtained with the Gemini Multi-Object Spectrograph. None of the 19 galaxies for which a redshift was determined lies at the same distance as 3C 297. The optical spectral analysis of the new Gemini spectrum of 3C 297 reveals an isolated Type II radio-loud AGN. We also detected line broadening in [O ii ] λ 3728 with a FWHM about 1700 km s ^−1 and possible line shifts of up to 500–600 km s ^−1 . We postulate that the host galaxy of 3C 297 is a fossil group, in which most of the stellar mass has merged into a single object, leaving behind an X-ray halo.
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- 2022
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6. The X-Ray Polarization View of Mrk 421 in an Average Flux State as Observed By the Imaging X-Ray Polarimetry Explorer
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Laura Di Gesu, Immacolata Donnarumma, Fabrizio Tavecchio, Iván Agudo, Thibault Barnounin, Nicolò Cibrario, Niccolò Di Lalla, Alessandro Di Marco, Juan Escudero, Manel Errando, Svetlana G. Jorstad, Dawoon E. Kim, Pouya M. Kouch, Ioannis Liodakis, Elina Lindfors, Grzegorz Madejski, Herman L. Marshall, Alan P. Marscher, Riccardo Middei, Fabio Muleri, Ioannis Myserlis, Michela Negro, Nicola Omodei, Luigi Pacciani, Alessandro Paggi, Matteo Perri, Wayne H. Baumgartner, Stephen D. Bongiorno, Steven R. Ehlert, Jeffery J. Kolodziejczak, Stephen L. O’Dell, Brian D. Ramsey, Allyn F. Tennant, Nicolas E. Thomas, and Martin C. Weisskopf
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Astrophysics - Abstract
Particle acceleration mechanisms in supermassive black hole jets, such as shock acceleration, magnetic reconnection, and turbulence, are expected to have observable signatures in the multiwavelength polarization properties of blazars. The recent launch of the Imaging X-Ray Polarimetry Explorer (IXPE) enables us, for the first time, to use polarization in the X-ray band (2–8 keV) to probe the properties of the jet synchrotron emission in high-synchrotron-peaked BL Lac objects (HSPs). We report the discovery of X-ray linear polarization (degree Πx = 15% ± 2% and electric vector position angle ψx = 35° ± 4°) from the jet of the HSP Mrk 421 in an average X-ray flux state. At the same time, the degree of polarization at optical, infrared, and millimeter wavelengths was found to be lower by at least a factor of 3. During the IXPE pointing, the X-ray flux of the source increased by a factor of 2.2, while the polarization behavior was consistent with no variability. The higher level of Πx compared to longer wavelengths, and the absence of significant polarization variability, suggest a shock is the most likely X-ray emission site in the jet of Mrk 421 during the observation. The multiwavelength polarization properties are consistent with an energy-stratified electron population, where the particles emitting at longer wavelengths are located farther from the acceleration site, where they experience a more disordered magnetic field.
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- 2022
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7. Temperature profiles of hot gas in early-type galaxies
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Dong-Woo Kim, Liam Traynor, Alessandro Paggi, Ewan O'Sullivan, Craig Anderson, Douglas Burke, Raffaele D'Abrusco, Giuseppina Fabbiano, Antonella Fruscione, Jennifer Lauer, Michael McCollough, Douglas Morgan, Amy Mossman, Saeqa Vrtilek, and Ginevra Trinchieri
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- 2019
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8. An XMM-Newton Early-type Galaxy Atlas
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Nazma Islam, Dong-Woo Kim, Kenneth Lin, Ewan O'Sullivan, Craig Anderson, Giuseppina Fabbiano, Jennifer Lauer, Douglas Morgan, Amy Mossman, and Alessandro Paggi
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Astrophysics ,Astronomy - Abstract
The distribution of hot interstellar medium in early-type galaxies(ETGs)bears the imprint of the various astrophysical processes it underwent during its evolution. The X-ray observations of these galaxies have identified various structural features related to active galactic nucleus(AGN)and stellar feedback and environmental effects such as merging and sloshing. In our XMM-Newton Galaxy Atlas(NGA)project, we analyze archival observations of 38 ETGs, utilizing the high sensitivity and large field of view of XMM-Newton to construct spatially resolved 2D spectral maps of the hot gas halos. To illustrate our NGA data products in conjunction with the Chandra Galaxy Atlas, we describe two distinct galaxies, NGC 4636 and NGC 1550, in detail. We discuss the revolutionary history with a particular focus on the asymmetric distribution of metal-enriched, low-entropy gas caused by sloshing and AGN-driven uplift. We will release the NGA data products to a dedicated website, from where users can download them to perform further analyses.
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- 2021
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9. High-frequency Radio Imaging of 3CR 403.1 with the Sardinia Radio Telescope
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Valentina Missaglia, Matteo Murgia, Francesco Massaro, Alessandro Paggi, Ana Jimenez-Gallardo, William R. Forman, Ralph P. Kraft, and Barbara Balmaverde
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- 2022
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10. Polarized blazar X-rays imply particle acceleration in shocks
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Ioannis Liodakis, Alan P. Marscher, Iván Agudo, Andrei V. Berdyugin, Maria I. Bernardos, Giacomo Bonnoli, George A. Borman, Carolina Casadio, Vı́ctor Casanova, Elisabetta Cavazzuti, Nicole Rodriguez Cavero, Laura Di Gesu, Niccoló Di Lalla, Immacolata Donnarumma, Steven R. Ehlert, Manel Errando, Juan Escudero, Maya Garcı́a-Comas, Beatriz Agı́s-González, César Husillos, Jenni Jormanainen, Svetlana G. Jorstad, Masato Kagitani, Evgenia N. Kopatskaya, Vadim Kravtsov, Henric Krawczynski, Elina Lindfors, Elena G. Larionova, Grzegorz M. Madejski, Frédéric Marin, Alessandro Marchini, Herman L. Marshall, Daria A. Morozova, Francesco Massaro, Joseph R. Masiero, Dimitri Mawet, Riccardo Middei, Maxwell A. Millar-Blanchaer, Ioannis Myserlis, Michela Negro, Kari Nilsson, Stephen L. O’Dell, Nicola Omodei, Luigi Pacciani, Alessandro Paggi, Georgia V. Panopoulou, Abel L. Peirson, Matteo Perri, Pierre-Olivier Petrucci, Juri Poutanen, Simonetta Puccetti, Roger W. Romani, Takeshi Sakanoi, Sergey S. Savchenko, Alfredo Sota, Fabrizio Tavecchio, Samaporn Tinyanont, Andrey A. Vasilyev, Zachary R. Weaver, Alexey V. Zhovtan, Lucio A. Antonelli, Matteo Bachetti, Luca Baldini, Wayne H. Baumgartner, Ronaldo Bellazzini, Stefano Bianchi, Stephen D. Bongiorno, Raffaella Bonino, Alessandro Brez, Niccoló Bucciantini, Fiamma Capitanio, Simone Castellano, Stefano Ciprini, Enrico Costa, Alessandra De Rosa, Ettore Del Monte, Alessandro Di Marco, Victor Doroshenko, Michal Dovčiak, Teruaki Enoto, Yuri Evangelista, Sergio Fabiani, Riccardo Ferrazzoli, Javier A. Garcia, Shuichi Gunji, Kiyoshi Hayashida, Jeremy Heyl, Wataru Iwakiri, Vladimir Karas, Takao Kitaguchi, Jeffery J. Kolodziejczak, Fabio La Monaca, Luca Latronico, Simone Maldera, Alberto Manfreda, Andrea Marinucci, Giorgio Matt, Ikuyuki Mitsuishi, Tsunefumi Mizuno, Fabio Muleri, Stephen C.-Y. Ng, Chiara Oppedisano, Alessandro Papitto, George G. Pavlov, Melissa Pesce-Rollins, Maura Pilia, Andrea Possenti, Brian D. Ramsey, John Rankin, Ajay Ratheesh, Carmelo Sgró, Patrick Slane, Paolo Soffitta, Gloria Spandre, Toru Tamagawa, Roberto Taverna, Yuzuru Tawara, Allyn F. Tennant, Nicolas E. Thomas, Francesco Tombesi, Alessio Trois, Sergey Tsygankov, Roberto Turolla, Jacco Vink, Martin C. Weisskopf, Kinwah Wu, Fei Xie, Silvia Zane, Liodakis, Ioanni, Marscher, Alan P, Agudo, Iván, Berdyugin, Andrei V, Bernardos, Maria I, Bonnoli, Giacomo, Borman, George A, Casadio, Carolina, Casanova, Vı Ctor, Cavazzuti, Elisabetta, Rodriguez Cavero, Nicole, Di Gesu, Laura, Di Lalla, Niccoló, Donnarumma, Immacolata, Ehlert, Steven R, Errando, Manel, Escudero, Juan, Garcı A-Comas, Maya, Agı S-González, Beatriz, Husillos, César, Jormanainen, Jenni, Jorstad, Svetlana G, Kagitani, Masato, Kopatskaya, Evgenia N, Kravtsov, Vadim, Krawczynski, Henric, Lindfors, Elina, Larionova, Elena G, Madejski, Grzegorz M, Marin, Frédéric, Marchini, Alessandro, Marshall, Herman L, Morozova, Daria A, Massaro, Francesco, Masiero, Joseph R, Mawet, Dimitri, Middei, Riccardo, Millar-Blanchaer, Maxwell A, Myserlis, Ioanni, Negro, Michela, Nilsson, Kari, O'Dell, Stephen L, Omodei, Nicola, Pacciani, Luigi, Paggi, Alessandro, Panopoulou, Georgia V, Peirson, Abel L, Perri, Matteo, Petrucci, Pierre-Olivier, Poutanen, Juri, Puccetti, Simonetta, Romani, Roger W, Sakanoi, Takeshi, Savchenko, Sergey S, Sota, Alfredo, Tavecchio, Fabrizio, Tinyanont, Samaporn, Vasilyev, Andrey A, Weaver, Zachary R, Zhovtan, Alexey V, Antonelli, Lucio A, Bachetti, Matteo, Baldini, Luca, Baumgartner, Wayne H, Bellazzini, Ronaldo, Bianchi, Stefano, Bongiorno, Stephen D, Bonino, Raffaella, Brez, Alessandro, Bucciantini, Niccoló, Capitanio, Fiamma, Castellano, Simone, Ciprini, Stefano, Costa, Enrico, De Rosa, Alessandra, Del Monte, Ettore, Di Marco, Alessandro, Doroshenko, Victor, Dovčiak, Michal, Enoto, Teruaki, Evangelista, Yuri, Fabiani, Sergio, Ferrazzoli, Riccardo, Garcia, Javier A, Gunji, Shuichi, Hayashida, Kiyoshi, Heyl, Jeremy, Iwakiri, Wataru, Karas, Vladimir, Kitaguchi, Takao, Kolodziejczak, Jeffery J, La Monaca, Fabio, Latronico, Luca, Maldera, Simone, Manfreda, Alberto, Marinucci, Andrea, Matt, Giorgio, Mitsuishi, Ikuyuki, Mizuno, Tsunefumi, Muleri, Fabio, Ng, Stephen C-Y, Oppedisano, Chiara, Papitto, Alessandro, Pavlov, George G, Pesce-Rollins, Melissa, Pilia, Maura, Possenti, Andrea, Ramsey, Brian D, Rankin, John, Ratheesh, Ajay, Sgró, Carmelo, Slane, Patrick, Soffitta, Paolo, Spandre, Gloria, Tamagawa, Toru, Taverna, Roberto, Tawara, Yuzuru, Tennant, Allyn F, Thomas, Nicolas E, Tombesi, Francesco, Trois, Alessio, Tsygankov, Sergey, Turolla, Roberto, Vink, Jacco, Weisskopf, Martin C, Wu, Kinwah, Xie, Fei, Zane, Silvia, High Energy Astrophys. & Astropart. Phys (API, FNWI), Gravitation and Astroparticle Physics Amsterdam, and Ministerio de Ciencia e Innovación (España)
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High Energy Astrophysical Phenomena (astro-ph.HE) ,High-energy astrophysics ,Multidisciplinary ,Settore FIS/05 ,FOS: Physical sciences ,Astrophysics - High Energy Astrophysical Phenomena ,High-energy astrophysics, Particle astrophysics ,Particle astrophysics - Abstract
Full list of authors: Liodakis, Ioannis; Marscher, Alan P.; Agudo, Ivan; Berdyugin, Andrei V.; Bernardos, Maria I.; Bonnoli, Giacomo; Borman, George A.; Casadio, Carolina; Casanova, Victor; Cavazzuti, Elisabetta; Cavero, Nicole Rodriguez; Di Gesu, Laura; Di Lalla, Niccolo; Donnarumma, Immacolata; Ehlert, Steven R.; Errando, Manel; Escudero, Juan; Garcia-Comas, Maya; Agis-Gonzalez, Beatriz; Husillos, Cesar; Jormanainen, Jenni; Jorstad, Svetlana G.; Kagitani, Masato; Kopatskaya, Evgenia N.; Kravtsov, Vadim; Krawczynski, Henric; Lindfors, Elina; Larionova, Elena G.; Madejski, Grzegorz M.; Marin, Frederic; Marchini, Alessandro; Marshall, Herman L.; Morozova, Daria A.; Massaro, Francesco; Masiero, Joseph R.; Mawet, Dimitri; Middei, Riccardo; Millar-Blanchaer, Maxwell A.; Myserlis, Ioannis; Negro, Michela; Nilsson, Kari; O'Dell, Stephen L.; Omodei, Nicola; Pacciani, Luigi; Paggi, Alessandro; Panopoulou, Georgia V.; Peirson, Abel L.; Perri, Matteo; Petrucci, Pierre-Olivier; Poutanen, Juri; Puccetti, Simonetta; Romani, Roger W.; Sakanoi, Takeshi; Savchenko, Sergey S.; Sota, Alfredo; Tavecchio, Fabrizio; Tinyanont, Samaporn; Vasilyev, Andrey A.; Weaver, Zachary R.; Zhovtan, Alexey V.; Antonelli, Lucio A.; Bachetti, Matteo; Baldini, Luca; Baumgartner, Wayne H.; Bellazzini, Ronaldo; Bianchi, Stefano; Bongiorno, Stephen D.; Bonino, Raffaella; Brez, Alessandro; Bucciantini, Niccolo; Capitanio, Fiamma; Castellano, Simone; Ciprini, Stefano; Costa, Enrico; De Rosa, Alessandra; Del Monte, Ettore; Di Marco, Alessandro; Doroshenko, Victor; Dovciak, Michal; Enoto, Teruaki; Evangelista, Yuri; Fabiani, Sergio; Ferrazzoli, Riccardo; Garcia, Javier A.; Gunji, Shuichi; Hayashida, Kiyoshi; Heyl, Jeremy; Iwakiri, Wataru; Karas, Vladimir; Kitaguchi, Takao; Kolodziejczak, Jeffery J.; La Monaca, Fabio; Latronico, Luca; Maldera, Simone; Manfreda, Alberto; Marinucci, Andrea; Matt, Giorgio; Mitsuishi, Ikuyuki; Mizuno, Tsunefumi; Muleri, Fabio; Ng, Stephen C. -Y.; Oppedisano, Chiara; Papitto, Alessandro; Pavlov, George G.; Pesce-Rollins, Melissa; Pilia, Maura; Possenti, Andrea; Ramsey, Brian D.; Rankin, John; Ratheesh, Ajay; Sgro, Carmelo; Slane, Patrick; Soffitta, Paolo; Spandre, Gloria; Tamagawa, Toru; Taverna, Roberto; Tawara, Yuzuru; Tennant, Allyn F.; Thomas, Nicolas E.; Tombesi, Francesco; Trois, Alessio; Tsygankov, Sergey; Turolla, Roberto; Vink, Jacco; Weisskopf, Martin C.; Wu, Kinwah; Xie, Fei; Zane, Silvia.--This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to around 1 TeV. Although the jets are known to be ultimately powered by a supermassive black hole, how the particles are accelerated to such high energies has been an unanswered question. The process must be related to the magnetic field, which can be probed by observations of the polarization of light from the jets. Measurements of the radio to optical polarization—the only range available until now—probe extended regions of the jet containing particles that left the acceleration site days to years earlier1,2,3, and hence do not directly explore the acceleration mechanism, as could X-ray measurements. Here we report the detection of X-ray polarization from the blazar Markarian 501 (Mrk 501). We measure an X-ray linear polarization degree ΠX of around 10%, which is a factor of around 2 higher than the value at optical wavelengths, with a polarization angle parallel to the radio jet. This points to a shock front as the source of particle acceleration and also implies that the plasma becomes increasingly turbulent with distance from the shock. © The Author(s) 2022., I.L. was supported by the JSPS postdoctoral short-term fellowship programme. The Imaging X-ray Polarimetry Explorer (IXPE) is a joint US and Italian mission. The US contribution is supported by the National Aeronautics and Space Administration (NASA) and led and managed by its Marshall Space Flight Center (MSFC), with industry partner Ball Aerospace (contract NNM15AA18C). The Italian contribution is supported by the Italian Space Agency (Agenzia Spaziale Italiana, ASI) through contract ASI-OHBI-2017-12-I.0, agreements ASI-INAF-2017-12-H0 and ASI-INFN-2017.13-H0, and its Space Science Data Center (SSDC) with agreements ASI-INAF-2022-14-HH.0 and ASI-INFN 2021-43-HH.0, and by the Istituto Nazionale di Astrofisica (INAF) and the Istituto Nazionale di Fisica Nucleare (INFN) in Italy. This research used data products provided by the IXPE Team (MSFC, SSDC, INAF and INFN) and distributed with additional software tools by the High-Energy Astrophysics Science Archive Research Center (HEASARC), at NASA Goddard Space Flight Center (GSFC). Data from the Steward Observatory spectropolarimetric monitoring project were used. This programme is supported by Fermi Guest Investigator grants NNX08AW56G, NNX09AU10G, NNX12AO93G and NNX15AU81G. This research has made use of data from the RoboPol programme, a collaboration between Caltech, the University of Crete, the Institute of Astrophysics-Foundation for Research and Technology (IA-FORTH), the Inter-University Centre for Astronomy and Astrophysics (IUCAA), the Max Planck Institute for Radioastronomy (MPIfR) and the Nicolaus Copernicus University, which was conducted at Skinakas Observatory in Crete, Greece. The Instituto Astrofísica Andalucía (IAA)-Consejo Superior de Investigaciones Científicas (CSIC) co-authors acknowledge financial support from the Spanish Ministerio de Ciencia e Innovacion (MCINN) through the ‘Center of Excellence Severo Ochoa‘ award for the Instituto de Astrofisica de Andalucia-CSIC (SEV-2017-0709). Acquisition and reduction of the POLAMI and Monitoring AGN with Polarimetry at the Calar Alto Telescopes (MAPCAT) data were supported in part by Ministerio de Ciencia e Innovación (MICINN) through grants AYA2016-80889-P and PID2019-107847RB-C44. The POLAMI observations were carried out at the IRAM 30 m Telescope. IRAM is supported by the National Institute of Sciences of the Universe (INSU)/Scientific Research National Center (CNRS) (France), Max-Planck-Gesellschaft (MPG) (Germany) and Instituto Geográfico Nacional (IGN) (Spain). The research at Boston University was supported in part by National Science Foundation grant AST-2108622, NASA Fermi Guest Investigator grant 80NSSC21K1917 and NASA Swift Guest Investigator grant 80NSSC22K0537. This study uses observations conducted with the 1.8 m Perkins Telescope Observatory in Arizona (USA), which is owned and operated by Boston University. Based on observations obtained at the Hale Telescope, Palomar Observatory as part of a continuing collaboration between the California Institute of Technology, NASA/Jet Propulsion Laboratory (JPL), Yale University and the National Astronomical Observatories of China. This research made use of Photutils, an Astropy package for detection and photometry of astronomical sources60. G.V.P. acknowledges support by NASA through the NASA Hubble Fellowship grant no. HST-HF2-51444.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555. Based on observations made with the Nordic Optical Telescope, owned in collaboration by the University of Turku and Aarhus University, and operated jointly by Aarhus University, the University of Turku and the University of Oslo, representing Denmark, Finland and Norway, the University of Iceland and Stockholm University at the Observatorio del Roque de los Muchachos, La Palma, Spain, of the Instituto de Astrofisica de Canarias. The data presented here were obtained (in part) with ALFOSC, which is provided by the Instituto de Astrofisica de Andalucia (IAA) under a joint agreement with the University of Copenhagen and the Nordic Optical Telescope. V.K. thanks the Vilho, Yrjö and Kalle Väisälä Foundation. J.J. was supported by Academy of Finland project 320085. E.L. was supported by Academy of Finland projects 317636 and 320045. Part of the French contribution was supported by the CNRS and the French spatial agency (CNES). Based on observations collected at the Observatorio de Sierra Nevada, owned and operated by the Instituto de Astrofisica de Andalucia (IAA-CSIC). Based on observations collected at the Centro Astronomico Hispano-Aleman (CAHA), proposal 22A-2.2-015, operated jointly by Junta de Andalucia and Consejo Superior de Investigaciones Cientificas (IAA-CSIC).
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- 2022
11. Imaging X-ray Polarimetry Explorer: prelaunch
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Martin C. Weisskopf, Paolo Soffitta, Luca Baldini, Brian D. Ramsey, Stephen L. O’Dell, Roger W. Romani, Giorgio Matt, William D. Deininger, Wayne H. Baumgartner, Ronaldo Bellazzini, Enrico Costa, Jeffery J. Kolodziejczak, Luca Latronico, Herman L. Marshall, Fabio Muleri, Stephen D. Bongiorno, Allyn Tennant, Niccolo Bucciantini, Michal Dovciak, Frederic Marin, Alan Marscher, Juri Poutanen, Pat Slane, Roberto Turolla, William Kalinowski, Alessandro Di Marco, Sergio Fabiani, Massimo Minuti, Fabio La Monaca, Michele Pinchera, John Rankin, Carmelo Sgro’, Alessio Trois, Fei Xie, Cheryl Alexander, D. Zachery Allen, Fabrizio Amici, Jason Andersen, Angelo Antonelli, Spencer Antoniak, Primo Attinà, Mattia Barbanera, Matteo Bachetti, Randy M. Baggett, Jeff Bladt, Alessandro Brez, Raffaella Bonino, Christopher Boree, Fabio Borotto, Shawn Breeding, Daniele Brienza, H. Kyle Bygott, Ciro Caporale, Claudia Cardelli, Rita Carpentiero, Simone Castellano, Marco Castronuovo, Luca Cavalli, Elisabetta Cavazzuti, Marco Ceccanti, Mauro Centrone, Saverio Citraro, Fabio D’Amico, Elisa D’Alba, Laura Di Gesu, Ettore Del Monte, Kurtis L. Dietz, Niccolo’ Di Lalla, Giuseppe Di Persio, David Dolan, Immacolata Donnarumma, Yuri Evangelista, Kevin Ferrant, Riccardo Ferrazzoli, MacKenzie Ferrie, Joseph Footdale, Brent Forsyth, Michelle Foster, Benjamin Garelick, Shuichi Gunji, Eli Gurnee, Michael Head, Grant Hibbard, Samantha Johnson, Erik Kelly, Kiranmayee Kilaru, Carlo Lefevre, Shelley Le Roy, Pasqualino Loffredo, Paolo Lorenzi, Leonardo Lucchesi, Tyler Maddox, Guido Magazzu, Simone Maldera, Alberto Manfreda, Elio Mangraviti, Marco Marengo, Alessandra Marrocchesi, Francesco Massaro, David Mauger, Jeffrey McCracken, Michael McEachen, Rondal Mize, Paolo Mereu, Scott Mitchell, Ikuyuki Mitsuishi, Alfredo Morbidini, Federico Mosti, Hikmat Nasimi, Barbara Negri, Michela Negro, Toan Nguyen, Isaac Nitschke, Alessio Nuti, Mitch Onizuka, Chiara Oppedisano, Leonardo Orsini, Darren Osborne, Richard Pacheco, Alessandro Paggi, Will Painter, Steven D. Pavelitz, Christina Pentz, Raffaele Piazzolla, Matteo Perri, Melissa Pesce-Rollins, Colin Peterson, Maura Pilia, Alessandro Profeti, Simonetta Puccetti, Jaganathan Ranganathan, Ajay Ratheesh, Lee Reedy, Noah Root, Alda Rubini, Stephanie Ruswick, Javier Sanchez, Paolo Sarra, Francesco Santoli, Emanuele Scalise, Andrea Sciortino, Christopher Schroeder, Tim Seek, Kalie Sosdian, Gloria Spandre, Chet O. Speegle, Toru Tamagawa, Marcello Tardiola, Antonino Tobia, Nicholas E. Thomas, Robert Valerie, Marco Vimercati, Amy L. Walden, Bruce Weddendorf, Jeffrey Wedmore, David Welch, Davide Zanetti, Francesco Zanetti, Weisskopf, M. C., Soffitta, P., Baldini, L., Ramsey, B. D., O'Dell, S. L., Romani, R. W., Matt, G., Deininger, W. D., Baumgartner, W. H., Bellazzini, R., Costa, E., Kolodziejczak, J. J., Latronico, L., Marshall, H. L., Muleri, F., Bongiorno, S. D., Tennant, A., Bucciantini, N., Dovciak, M., Marin, F., Marscher, A., Poutanen, J., Slane, P., Turolla, R., Kalinowski, W., Di Marco, A., Fabiani, S., Minuti, M., La Monaca, F., Pinchera, M., Rankin, J., Sgro', C., Trois, A., Xie, F., Alexander, C., Allen, D. Z., Amici, F., Andersen, J., Antonelli, A., Antoniak, S., Attina, P., Barbanera, M., Bachetti, M., Baggett, R. M., Bladt, J., Brez, A., Bonino, R., Boree, C., Borotto, F., Breeding, S., Brienza, D., Bygott, H. K., Caporale, C., Cardelli, C., Carpentiero, R., Castellano, S., Castronuovo, M., Cavalli, L., Cavazzuti, E., Ceccanti, M., Centrone, M., Citraro, S., D'Amico, F., D'Alba, E., Di Gesu, L., Del Monte, E., Dietz, K. L., Di Lalla, N., Persio, G. D., Dolan, D., Donnarumma, I., Evangelista, Y., Ferrant, K., Ferrazzoli, R., Ferrie, M., Footdale, J., Forsyth, B., Foster, M., Garelick, B., Gunji, S., Gurnee, E., Head, M., Hibbard, G., Johnson, S., Kelly, E., Kilaru, K., Lefevre, C., Roy, S. L., Loffredo, P., Lorenzi, P., Lucchesi, L., Maddox, T., Magazzu, G., Maldera, S., Manfreda, A., Mangraviti, E., Marengo, M., Marrocchesi, A., Massaro, F., Mauger, D., Mccracken, J., Mceachen, M., Mize, R., Mereu, P., Mitchell, S., Mitsuishi, I., Morbidini, A., Mosti, F., Nasimi, H., Negri, B., Negro, M., Nguyen, T., Nitschke, I., Nuti, A., Onizuka, M., Oppedisano, C., Orsini, L., Osborne, D., Pacheco, R., Paggi, A., Painter, W., Pavelitz, S. D., Pentz, C., Piazzolla, R., Perri, M., Pesce-Rollins, M., Peterson, C., Pilia, M., Profeti, A., Puccetti, S., Ranganathan, J., Ratheesh, A., Reedy, L., Root, N., Rubini, A., Ruswick, S., Sanchez, J., Sarra, P., Santoli, F., Scalise, E., Sciortino, A., Schroeder, C., Seek, T., Sosdian, K., Spandre, G., Speegle, C. O., Tamagawa, T., Tardiola, M., Tobia, A., Thomas, N. E., Valerie, R., Vimercati, M., Walden, A. L., Weddendorf, B., Wedmore, J., Welch, D., Zanetti, D., and Zanetti, F.
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grazing-incidence optic ,Space and Planetary Science ,Control and Systems Engineering ,Mechanical Engineering ,gas pixel detector ,Astronomy and Astrophysics ,x-ray polarimetry ,Astrophysics - Instrumentation and Methods for Astrophysics ,Instrumentation ,Electronic, Optical and Magnetic Materials - Abstract
Launched on 2021 December 9, the Imaging X-ray Polarimetry Explorer (IXPE) is a NASA Small Explorer Mission in collaboration with the Italian Space Agency (ASI). The mission will open a new window of investigation—imaging x-ray polarimetry. The observatory features three identical telescopes, each consisting of a mirror module assembly with a polarization-sensitive imaging x-ray detector at the focus. A coilable boom, deployed on orbit, provides the necessary 4-m focal length. The observatory utilizes a three-axis-stabilized spacecraft, which provides services such as power, attitude determination and control, commanding, and telemetry to the ground. During its 2-year baseline mission, IXPE will conduct precise polarimetry for samples of multiple categories of x-ray sources, with follow-on observations of selected targets.
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- 2022
12. The Imaging X-Ray Polarimetry Explorer (IXPE): technical overview IV
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D. Zachery Allen, Stephen D. Bongiorno, Lee Reedy, M. Ceccanti, Tim Seek, Stephen L. O'Dell, MacKenzie Ferrie, Paolo Sarra, Chet O. Speegle, H.Kyle Byggott, John Rankin, Joseph Footdale, Kevin Ferrant, Carmelo Sgrò, Noah Root, Alessio Nuti, Alda Rubini, Ciro Caporale, Steven D. Pavelitz, Scott C. Mitchell, Maura Pilia, Ettore Delmonte, Toan Nguyen, Marcello Tardiola, S. Castellano, Federico Mosti, Christopher Schroeder, Randy M. Baggett, C. Oppedisano, Simonetta Puccetti, Allyn F. Tennant, Brent Forsyth, Marco Vimercati, Enrico Costa, Alessio Trois, Marco Castronuovo, Giusseppe Di Persio, Grant Hibbard, Elisabetta Cavazutti, Hikmat Nasimi, Nicholas Thomas, Leonardo Orsini, Jeff Bladt, Christopher Boree, Paolo Soffitta, Elisa D'Alba, Francesco Santoli, Eric Kelly, Saverio Citraro, Michele Pinchera, Michelle Foster, Daniele Brienza, Francesco Zanetti, M. Negro, Roger W. Romani, Kalie Sosdian, Riccardo Ferrazzoli, Antonino Tobia, Sergio Fabiani, Darren Osborne, Herman L. Marshall, Elio Mangravati, Michael McEachen, Brian D. Ramsey, Claudia Cardelli, Ajay Ratheesh, Giorgio Matt, Pasqualino Lofredo, Richard Pacheco, Jeffery J. Kolodziejczak, Samantha Johnson, I. Donnarumma, Jeffery Wedmore, Y. Evangelista, Shuichi Gunji, Colin Peterson, Fabio La Monaca, Christina Pentz, Kurtis L. Dietz, Ronaldo Bellazzini, M. Perri, Mauro Centrone, Javier Sánchez, Fabio Borotto, Jason Andersen, Alberto Manfreda, Gloria Spandre, Isaac Nitschke, Mitch Onizuka, Alessandro Brez, Alessandra Marrocchesi, Fabio D'Amico, Shawn Breeding, Jeffrey McCracken, Francesco Massaro, Will Painter, Rafaella Bonino, Michael Head, Shelley Le Roy, Kiranmayee Kilaru, Paolo Mereu, Raffaele Piazzolla, Luca Cavalli, William D. Deininger, Fabrizio Amici, Martin C. Weisskopf, F. Muleri, Cheryl Alexander, S. Maldera, Andrea Sciortino, Primo Attina, Leonardo Lucchesi, David Welch, E. Scalise, Barbara Negri, Angelo Antonelli, Jaganathan Ranganathan, Matteo Bachetti, Benjamin Garelick, Carlo Lefevre, Mattia Barbanera, W. H. Baumgartner, Marco Marengo, Niccolò Di Lalla, Ikuyuki Mitsuishi, William Kalinowski, Stephanie Ruswick, Bruce Weddendorf, Eli Gurnee, Toru Tamagawa, Fei Xie, Amy L. Walden, Robert Valerie, Luca Latronico, Massimo Minuti, David Dolan, Rita Carpentiero, Rondal Mize, David Mauger, Alessandro Profeti, Paolo Lorenzi, Alessandro Paggi, Melissa Pesce-Rollins, Luca Baldini, Alessandro Di Marco, Alfredo Morbidini, Guido Magazzu, Spencer Antoniak, and Tyler Maddox
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Spacecraft ,gas pixel detectors ,Computer science ,Payload ,business.industry ,grazing-incidence optics ,Detector ,Polarimetry ,law.invention ,Telescope ,X-ray polarimetry ,law ,Observatory ,Orbit (dynamics) ,Focal length ,X-ray polarimetry, gas pixel detectors, grazing-incidence optics ,business ,Remote sensing - Abstract
Scheduled to launch in late 2021 the Imaging X-ray Polarimetry Explorer (IXPE) is a Small Explorer Mission designed to open up a new window of investigation -- X-ray polarimetry. The IXPE observatory features 3 identical telescope each consisting of a mirror module assembly with a polarization-sensitive imaging x-ray detector at its focus. An extending beam, deployed on orbit provides the necessary 4 m focal length. The payload sits atop a 3-axis stabilized spacecraft which among other things provides power, attitude determination and control, commanding, and telemetry to the ground. During its 2-year baseline mission, IXPE will conduct precise polarimetry for samples of multiple categories of x-ray sources, with follow-on observations of selected targets. IXPE is a partnership between NASA and the Italian Space Agency (ASI).
- Published
- 2021
13. Multi-Messenger observations of the Fermi-LAT blazar 4FGL J0658.6+0636 consistent with an IceCube high-energy neutrino
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David R. Williams, Antoine Kouchner, K. A. Farrell, Alasdair E. Gent, V. V. Vassiliev, Fabian Schüssler, H. A. Peña-Herazo, Georgios Paraschos, R. Shang, D. S. Hanna, Q. Feng, John L. Quinn, D. Ribeiro, Daniel Nieto, A. Brill, Giacomo Bonnoli, M. Kertzman, Lucy Fortson, Yong Sheng, Olivier Hervet, T. B. Humensky, Francesco Massaro, S. O'Brien, Alessio Berti, M. J. Lang, donggeun tak, Teddy Cheung, Suvi Gezari, Joern Wilms, A. D. Falcone, P. T. Reynolds, Miguel Perez-Torres, Andrea Tramacere, Reshmi Mukherjee, G. M. Foote, Binita Hona, C. Giuri, Raniere de Menezes, P. Kaaret, I. Sadeh, Frank J. Masci, Emilio Fernandez-Garcia, W. Jin, Wystan Benbow, Uwe Bach, R. R. Prado, P. Moriarty, Jonas Heßdörfer, M. Pohl, Matthias Kadler, Steven Hämmerich, Gernot Maier, G. H. Sembroski, Andrea Gokus, R. A. Ong, M. Capasso, Ivan Agudo, Marcos Santander, C. E. McGrath, T. J. Williamson, A. J.R. Weinstein, E. Roache, A. Archer, Jorge Otero-Santos, Simone Garrappa, Alex Kraus, G. H. Gillanders, A. J. Castro-Tirado, Alexis Coleiro, Jodi Christiansen, Jamie Holder, K. Ragan, Meenakshi Rajagopal, A. N. Otte, Alessandro Paggi, K. Pfrang, Orel Gueta, Marcello Giroletti, Cristina Nanci, Javier Moldon, M. Nievas-Rosillo, Elisa Bernardini, C. Adams, Werner Colmar, Y. D. Hu, J. A. Ryan, Richard Walters, M. Lundy, Florian Eppel, Tobias Kleiner, R. Sanchez-Ramirez, J. H. Buckley, A. J. Chromey, Amy Furniss, Charlotte Ward, Konstancja Satalecka, E. Pueschel, Manel Errando, Sara Buson, S. Kumar, S. Patel, M. D. Caballero-Garcia, and Marco Ajello
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Physics ,High energy ,Astrophysics ,Neutrino ,Blazar ,Fermi Gamma-ray Space Telescope - Published
- 2021
14. Extended X-ray Emission in Compton Thick AGN with Deep Chandra Observations
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Kieran Parker, W. P. Maksym, Junfeng Wang, A. Siemiginowska, Alessandro Paggi, Martin Elvis, Giuseppina Fabbiano, Mackenzie L. Jones, Jingzhe Ma, and Margarita Karovska
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Physics ,X-ray active galactic nuclei ,Active galaxies ,AGN host galaxies ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Active galactic nucleus ,Molecular cloud ,Astrophysics::High Energy Astrophysical Phenomena ,X-ray ,High resolution ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,New population ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Space and Planetary Science ,Ionization ,Astrophysics of Galaxies (astro-ph.GA) ,Disc ,Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics::Galaxy Astrophysics - Abstract
We present the spatial analysis of five Compton thick (CT) active galactic nuclei (AGNs), including MKN 573, NGC 1386, NGC 3393, NGC 5643, and NGC 7212, for which high resolution Chandra observations are available. For each source, we find hard X-ray emission (>3 keV) extending to ~kpc scales along the ionization cone, and for some sources, in the cross-cone region. This collection represents the first, high-signal sample of CT AGN with extended hard X-ray emission for which we can begin to build a more complete picture of this new population of AGN. We investigate the energy dependence of the extended X-ray emission, including possible dependencies on host galaxy and AGN properties, and find a correlation between the excess emission and obscuration, suggesting a connection between the nuclear obscuring material and the galactic molecular clouds. Furthermore, we find that the soft X-ray emission extends farther than the hard X-rays along the ionization cone, which may be explained by a galactocentric radial dependence on the density of molecular clouds due to the orientation of the ionization cone with respect to the galactic disk. These results are consistent with other CT AGN with observed extended hard X-ray emission (e.g., ESO 428-G014 and the Ma et al. 2020 CT AGN sample), further demonstrating the ubiquity of extended hard X-ray emission in CT AGN., 29 pages, 22 figures, 7 tables, Accepted for publication in ApJ
- Published
- 2021
15. Raining in MKW 3 s: A Chandra-MUSE Analysis of X-Ray Cold Filaments around 3CR 318.1
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Jeremy J. Harwood, Giacomo Venturi, B. Balmaverde, C. P. O'Dea, E. Sani, B. Wilkes, R. P. Kraft, F. Ricci, V. H. Mahatma, Stefi A. Baum, A. Jimenez-Gallardo, R. J. van Weeren, William B. Sparks, Elisabetta Liuzzo, Grant R. Tremblay, M. A. Prieto, Pasquale Mazzotta, C. Mazzucchelli, Alessandro Capetti, Francesco Massaro, William R. Forman, H. J. A. Röttgering, V. Missaglia, Ranieri D. Baldi, Joanna Kuraszkiewicz, Alessandro Paggi, Jimenez-Gallardo, A, Massaro, F, Balmaverde, B, Paggi, A, Capetti, A, Forman, Wr, Kraft, Rp, Baldi, Rd, Mahatma, Vh, Mazzucchelli, C, Missaglia, V, Ricci, F, Venturi, G, Baum, Sa, Liuzzo, E, O'Dea, Cp, Prieto, Ma, Rottgering, Hja, Sani, E, Sparks, Wb, Tremblay, Gr, van Weeren, Rj, Wilkes, Bj, Harwood, Jj, Mazzotta, P, Kuraszkiewicz, J, Jimenez-Gallardo, A., Massaro, F., Balmaverde, B., Paggi, A., Capetti, A., Forman, W.R., Kraft, R.P., Baldi, R.D., Mahatma, V.H., Mazzucchelli, C., Missaglia, V., Ricci, F., Venturi, G., Baum, S.A., Liuzzo, E., O'Dea, C.P., Prieto, M.A., Röttgering, H.J.A., Sani, E., Sparks, W.B., Tremblay, G.R., Van Weeren, R.J., Wilkes, B.J., Harwood, J.J., Mazzotta, P., and Kuraszkiewicz, J.
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Active galactic nucleus ,010504 meteorology & atmospheric sciences ,Galaxy clusters (584) ,Astrophysics - astrophysics of galaxies ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Radio active galactic nuclei (2134) ,Galaxy clusters ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics - high energy astrophysical phenomena ,01 natural sciences ,0103 physical sciences ,Cool cores (302) ,010303 astronomy & astrophysics ,Galaxy cluster ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Cool cores ,Physics ,Active galactic nuclei ,Settore FIS/05 ,Astronomy and Astrophysics ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Radio active galactic nuclei ,Active galactic nuclei (16) ,16, 2134, 584, 302 - Abstract
We present the analysis of X-ray and optical observations of gas filaments observed in the radio source 3CR 318.1, associated with NGC 5920, the Brightest Cluster Galaxy (BCG) of MKW 3s, a nearby cool core galaxy cluster. This work is one of the first X-ray and optical analyses of filaments in cool core clusters carried out using MUSE observations. We aim at identifying the main excitation processes responsible for the emission arising from these filaments. We complemented the optical VLT/MUSE observations, tracing the colder gas phase, with X-ray $\textit{Chandra}$ observations of the hotter highly ionized gas phase. Using the MUSE observations, we studied the emission line intensity ratios along the filaments to constrain the physical processes driving the excitation, and, using the $\textit{Chandra}$ observations, we carried out a spectral analysis of the gas along these filaments. We found a spatial association between the X-ray and optical morphology of these filaments, which are colder and have lower metal abundance than the surrounding intra-cluster medium (ICM), as already seen in other BCGs. Comparing with previous results from the literature for other BCGs, we propose that the excitation process that is most likely responsible for these filaments emission is a combination of star formation and shocks, with a likely contribution from self-ionizing, cooling ICM. Additionally, we conclude that the filaments most likely originated from AGN-driven outflows in the direction of the radio jet., 9 pages, 5 figures, ApJL accepted, pre-proof version
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- 2021
16. An Optical Overview of Blazars with LAMOST. II. Gamma-Ray Blazar Candidates and Updated Classifications
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H. A. Peña-Herazo, Minfeng Gu, N. Masetti, Alessandro Paggi, Federica Ricci, Francesco Massaro, Raffaele D'Abrusco, Marco Landoni, V. H. Chavushyan, Pena-Herazo, Ha, Massaro, F, Gu, Mf, Paggi, A, Landoni, M, D'Abrusco, R, Ricci, F, Masetti, N, Chavushyan, V, Peña-Herazo, H.A., Massaro, F., Gu, M., Paggi, A., Landoni, M., D'Abrusco, R., Ricci, F., Masetti, N., and Chavushyan, V.
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Physics ,Point source ,media_common.quotation_subject ,Gamma-ray sources (633) ,Astronomy and Astrophysics ,Astrophysics ,Flat-spectrum radio quasars (2163) ,Optical identification (1167) ,Redshift ,law.invention ,LAMOST ,Telescope ,Space and Planetary Science ,law ,Sky ,Spectroscopy (1558) ,BL Lacertae objects (158) ,Emission spectrum ,Blazar ,Blazars (164) ,media_common ,Fermi Gamma-ray Space Telescope - Abstract
Blazars represent the dominant class of associated γ-ray sources detected by the Fermi Large Area Telescope (LAT). However, in the more recent release of the Fourth Fermi-LAT Point Source Catalog (4FGL), ∼25% of the sources associated with lower-energy counterparts show a multifrequency behavior similar to that of blazars, but lacks an optical spectroscopic confirmation of their nature and are therefore classified as Blazar Candidates of Uncertain Type (BCUs). A particularly challenging task in blazar studies is to classify these BCUs and, when possible to estimate their redshifts, in particular for BL Lac objects, characterized by almost featureless optical spectra with only weak emission lines. Continuing our study of blazars with Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) optical spectral data, we perform an extensive search for optical spectra available in the LAMOST Data Release 6 archive. Our aim is confirming the blazar nature of BCUs and to test if new data can allow us to get a redshift estimate for BL Lac objects that lack measurement, as well as to search for and discover changing-look blazars. We selected sources out of the 4FGL catalog, the list of targets from our follow-up spectroscopic campaign of unidentified and/or unassociated γ-ray sources, and the Roma-BZCAT multifrequency catalog of blazars, finding a total of 42 sources with available LAMOST DR6 spectra. We confirmed the blazar-like nature of four blazar candidates . For the remaining 37 sources we confirm their previous classification. © 2021. The American Astronomical Society. All rights reserved.
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- 2021
17. Hidden Treasures in the Unknown 3CR Extragalactic Radio Sky: A Multiwavelength Approach
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Barbara Balmaverde, A. Maselli, Stefi A. Baum, A. Jimenez-Gallardo, Juan P. Madrid, F. Ricci, C. Stuardi, V. Missaglia, Elisabetta Liuzzo, Grant R. Tremblay, R. P. Kraft, Belinda Jane Wilkes, C. P. O'Dea, Alessandro Paggi, Alessandro Capetti, Francesco Massaro, D. E. Harris, William R. Forman, Joanna Kuraszkiewicz, Eleonora Sani, Missaglia V., Massaro F., Liuzzo E., Paggi A., Kraft R.P., Forman W.R., Jimenez-Gallardo A., Madrid J.P., Ricci F., Stuardi C., Wilkes B.J., Baum S.A., O'Dea C.P., Kuraszkiewicz J., Tremblay G.R., Maselli A., Capetti A., Sani E., Balmaverde B., Harris D.E., Missaglia, V, Massaro, F, Liuzzo, E, Paggi, A, Kraft, Rp, Forman, Wr, Jimenez-Gallardo, A, Madrid, Jp, Ricci, F, Stuardi, C, Wilkes, Bj, Baum, Sa, O'Dea, Cp, Kuraszkiewicz, J, Tremblay, Gr, Maselli, A, Capetti, A, Sani, E, Balmaverde, B, and Harris, De
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Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,X-ray astronomy ,Active galactic nucleus ,media_common.quotation_subject ,Astronomy ,FOS: Physical sciences ,Astronomy and Astrophysics ,Active galaxies (17) ,Space and Planetary Science ,Sky ,Radio continuum emission (1340) ,X-ray astronomy (1810) ,Astrophysics - High Energy Astrophysical Phenomena ,media_common - Abstract
We present the analysis of multi-wavelength observations of seven extragalactic radio sources, listed as unidentified in the Third Cambridge Revised Catalog (3CR). X-ray observations, performed during Chandra Cycle 21, were compared to VLA, WISE and Pan-STARRS observations in the radio, infrared and optical bands, respectively. All sources in this sample lack a clear optical counterpart, and are thus missing their redshift and optical classification. In order to confirm the X-ray and infrared radio counterparts of core and extended components, here we present for the first time radio maps obtained manually reducing VLA archival data. As in previous papers on the Chandra X-ray snapshot campaign, we report X-ray detections of radio cores and two sources, out of the seven presented here, are found to be members of galaxy clusters. For these two cluster sources (namely, 3CR 409 and 3CR 454.2), we derived surface brightness profiles in four directions. For all seven sources, we measured X-ray intensities of the radio sources and we also performed standard X-ray spectral analysis for the four sources (namely, 3CR 91, 3CR 390, 3CR 409 and 3CR 428) with the brightest nuclei (more than 400 photons in the 2'' nuclear region). We also detected extended X-ray emission around 3CR 390 and extended X-ray emission associated with the northern jet of 3CR 158. This paper represents the first attempt to give a multi-wavelength view of the unidentified radio sources listed in the 3CR catalog., Comment: 18 pages, 19 figures, 5 tables, accepted for publication on ApJS
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- 2021
18. AGN-host interaction in IC 5063. I. Large-scale X-ray morphology and spectral analysis
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R. Morganti, W. P. Maksym, Fabrizio Fiore, Martin Elvis, Giuseppina Fabbiano, A. Travascio, Tom Oosterloo, Alessandro Paggi, Astronomy, and ITA
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Photon ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Photoionization ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Spectral line ,0103 physical sciences ,Emission spectrum ,Disc ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common ,Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Active galactic nuclei ,X-ray active galactic nuclei ,010308 nuclear & particles physics ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Universe ,Interstellar medium ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,85-00 ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report the analysis of the deep (270 ks) X-ray Chandra data of one of the most radio-loud, Seyfert 2 galaxies in the nearby Universe (z=0.01135), IC 5063. The alignment of the radio structure with the galactic disk and ionized bi-cone, enables us to study the effects of both radio jet and nuclear irradiation on the interstellar medium (ISM). The nuclear and bi-cone spectra suggest a low photoionization phase mixed with a more ionized or thermal gas component, while the cross-cone spectrum is dominated by shocked and collisionally ionized gas emission. The clumpy morphology of the soft (3 keV) and the Fe K-alpha 6.4 keV emission are both extended to kpc size along the bi-cone direction, suggesting an interaction of nuclear photons with dense clouds in the galaxy disk, as observed in other Compton Thick (CT) active nuclei. The north-west cone spectrum also exhibits an Fe XXV emission line, which appears spatially extended and spatially correlated with the most intense radio hot-spot, suggesting jet-ISM interaction., 28 pages, 10 figures and 3 tables (with 10 more figures and 3 more tables in the Appendix), submitted to ApJ on May 24, 2021
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- 2021
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19. Optical Spectroscopic Observations of Gamma-ray Blazar Candidates. XI. Optical Observations from SOAR, Blanco, NTT and OAN-SPM. The Story so Far
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Marco Landoni, Fabio La Franca, Howard A. Smith, V. H. Chavushyan, Francesco Massaro, Federica Ricci, Elena Jiménez-Bailón, Dan Milisavljevic, Alessandro Paggi, N. Masetti, Raffaele D'Abrusco, Víctor M. Patiño-Álvarez, H. A. Peña-Herazo, E. J. Marchesini, Abigail García-Pérez, Gino Tosti, Raúl A. Amaya-Almazán, Pena-Herazo, H. A., Paggi, A., Garcia-Perez, A., Amaya-Almazan, R. A., Massaro, F., Ricci, F., Chavushyan, V., Marchesini, E. J., Masetti, N., Landoni, M., D'Abrusco, R., Milisavljevic, D., Jimenez-Bailon, E., Patino-Alvarez, V. M., La Franca, F., Smith, H. A., Tosti, G., Peña-Herazo, H.A., García-Pérez, A., Amaya-Almazán, R.A., Marchesini, E.J., Jiménez-Bailón, E., Patiño-Álvarez, V.M., and Smith, H.A.
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Physics ,Astrophysics::High Energy Astrophysical Phenomena ,Optical identification, Blazars, BL Lacertae objects, Flat-spectrum radio quasars ,Gamma ray ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,extended figures ,Flat-spectrum radio quasars (2163) ,Optical identification (1167) ,Space and Planetary Science ,BL Lacertae objects (158) ,Optical identification ,Soar ,Blazar ,Blazars (164) ,Astrophysics::Galaxy Astrophysics - Abstract
Blazars represent about 62% of the sources in the ?-ray Fermi-LAT catalog, and about 80% of the ?-ray sources associated with a lower-energy counterpart, dominating the ?-ray sky. In particular, about 42% of the ?-ray blazars are classified as Blazars Candidates of Uncertain type (BCUs) for which spectroscopic observations are mandatory to confirm their blazar nature. Here we report the spectra of 64 targets observed as part of our follow-up optical spectroscopic campaign. This sample includes 62 sources classified in Fermi-LAT catalog as BCUs, one source classified as a generic active galactic nucleus, and one source classified as a BL Lac in Fermi-LAT and as blazar of uncertain type in the Roma-BZCAT catalog. We confirm the blazar nature of all BCUs. We classify 33 of them as BL Lacs, 11 as Flat Spectrum Radio Quasars, and 18 as blazars with nonnegligible host-galaxy emission. We also classify the generic active galactic nucleus as a BL Lac. Finally, we confirm the classification of the BL Lac. We also reported a lower limit redshift for 43 sources. For 20 sources, we got redshift measurements consistent with the literature values. For the other 21 sources, we obtained their first spectroscopic redshift measurement; while, for two sources, we provide lower limits on the redshift. With the upcoming release of the sixth edition of the Roma-BZCAT Multifrequency Catalog of Blazars, we take the opportunity in the present work to present the collective results of the first phase of our optical spectroscopic follow-up campaign. © 2021. The American Astronomical Society. All rights reserved..
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- 2021
20. Turin-SyCAT: A multifrequency catalog of Seyfert galaxies
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V. H. Chavushyan, Francesco Massaro, Alessandro Paggi, N. Masetti, H. A. Peña-Herazo, and Alessandro Capetti
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Physics ,Galaxies: Seyfert ,Space and Planetary Science ,Catalogs ,Galaxies: Active ,Astronomy and Astrophysics ,Astrophysics ,Galaxy - Abstract
Aims. We present the first release of Turin-SyCAT, a multifrequency catalog of Seyfert galaxies. Methods. We selected Seyfert galaxies considering criteria based on radio, infrared, and optical properties and starting from sources belonging to hard X-ray catalogs and surveys. We visually inspected optical spectra available for all selected sources. We adopted homogeneous and stringent criteria in the source selection aiming at reducing the possible contamination from other source classes. Results. Our final catalog includes 351 Seyfert galaxies distinguished in 233 type 1 and 118 type 2. Type 1 Seyfert galaxies appear to have mid-IR colors similar to blazars, but are distinguished from them by their radio-loudness. Additionally, Seyfert 2 galaxies have mid-IR colors more similar to quasars than BL Lac objects. As expected from their spectral properties, type 1 and 2 Seyfert galaxies show a clear distinction when using the u − r color. Finally, we found a tight correlation between the mid-IR fluxes at both 12 and 22 μm (i.e., F12 and F22, respectively) and hard X-ray fluxes between 15 and 150 keV. Both Seyfert types appear to follow the same trend and share similar values of the ratios of F12 and F22 to FHX in agreement with expectations of the AGN unification scenario. Conclusions. As future perspectives, the Turin-SyCAT will then be used to search for heavily obscured Seyfert galaxies among unidentified hard X-ray sources, given the correlation between mid-IR and hard X-rays, and to investigate their large-scale environments.
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- 2022
21. Revisiting the complex nuclear region of NGC 6240 with Chandra
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Alessandro Paggi, Junfeng Wang, Emanuele Nardini, Martin Elvis, Giuseppina Fabbiano, and Margarita Karovska
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,Active galactic nucleus ,010504 meteorology & atmospheric sciences ,Molecular cloud ,Astrophysics::High Energy Astrophysical Phenomena ,Continuum (design consultancy) ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Submillimeter Array ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Redshift ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Surface brightness ,Astrophysics - High Energy Astrophysical Phenomena ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Line (formation) - Abstract
We present a reanalysis of the cumulative ACIS S Chandra data set pointed at the double AGNs of the NGC 6240 merging galaxy, focusing on the hard energy bands containing the hard spectral continuum (5.5-5.9 keV), the redshifted Fe I K alpha line (6.0-6.4 keV), and the redshifted Fe XXV line (6.4-6.7 keV). We have used to the full the Chandra telescope angular resolution, and we have modeled the Chandra PSF by comparing pre-flight calibration model to the data for the two bright AGNs. With two complementary approaches: (1) studying the residuals after PSF subtraction, and (2) producing reconstructed Expectation through Markov Chain Monte Carlo (EMC2) images, we are able to resolve structures extending from 1 kpc to, in press on The Astrophysical Journal
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- 2020
22. The $\gamma$-ray sky seen at X-ray energies II: the Swift hunt of Fermi BL Lac objects among unidentified gamma-ray sources
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E. J. Marchesini, Ileana Andruchow, N. Masetti, Raffaele D'Abrusco, Alessandro Paggi, Francesco Massaro, ITA, and USA
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Active galactic nucleus ,010504 meteorology & atmospheric sciences ,Infrared ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,Context (language use) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,law.invention ,Telescope ,law ,0103 physical sciences ,Spectroscopy ,Blazar ,010303 astronomy & astrophysics ,Galaxies: nuclei ,0105 earth and related environmental sciences ,media_common ,Physics ,Astronomy and Astrophysics ,BL Lacertae objects: general ,Galaxies: active ,Gamma rays: galaxies ,X-rays: galaxies ,Galaxies: jets ,Space and Planetary Science ,Sky ,Astrophysics - High Energy Astrophysical Phenomena ,Fermi Gamma-ray Space Telescope - Abstract
Nearly 50% of all sources detected by the Fermi Large Area Telescope are classified as blazars or blazar candidates, one of the most elusive classes of active galaxies. Additional blazars can also be hidden within the sample of unidentified or unassociated $\gamma$-ray sources (UGSs) that constitute about one-third of all gamma-ray sources detected to date. We recently confirmed that the large majority of Fermi blazars of the BL Lac subclass have an X-ray counterpart. Using the X-ray properties of a BL Lac training set and combining these with archival multifrequency information, we aim to search for UGSs that could have a BL Lac source within their $\gamma$-ray positional uncertainty regions. We reduced and analyzed the Swift X-ray observations of a selected sample of 327 UGSs. We then compared the X-ray fluxes and hardness ratios of all sources detected in the pointed fields with those of known Fermi BL Lacs. We find at least one X-ray source, lying within the $\gamma$-ray positional uncertainty at 95% confidence level, for 223 UGSs and a total of 464 X-ray sources in all fields analyzed. The X-ray properties of a large fraction of them, eventually combined with radio, infrared, and optical information, exhibit BL Lac multi-frequency behavior, thus allowing us to select high-confidence BL Lac candidates; some of them were recently observed during our optical spectroscopic campaign which confirmed their nature. We find that out of 50 X-ray sources that were confirmed as BL Lacs through optical spectroscopy, 12 do not show canonical mid-infrared or radio BL Lac properties. This indicates that the selection of X-ray BL Lac candidates is a strong method to find new counterparts within Fermi UGSs. Finally, we pinpoint a sample of 32 Swift/XRT candidate counterparts to Fermi UGSs that are most likely BL Lac objects., Comment: Published version
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- 2020
23. A New Multi-Wavelength Census of Blazars
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Matteo Bonato, M. Villata, C. M. Raiteri, G. de Zotti, M. I. Carnerero, and Alessandro Paggi
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QSOS ,Active galactic nucleus ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,galaxies: active ,FOS: Physical sciences ,Context (language use) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,catalogs ,01 natural sciences ,0103 physical sciences ,Blazar ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common ,Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,010308 nuclear & particles physics ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,Quasar ,Astrophysics - Astrophysics of Galaxies ,Redshift ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics - High Energy Astrophysical Phenomena ,Fermi Gamma-ray Space Telescope - Abstract
Context:Blazars are the rarest and most powerful active galactic nuclei, playing a crucial and growing role in today multi-frequency and multi-messenger astrophysics. Current blazar catalogs, however, are incomplete and particularly depleted at low Galactic latitudes. Aims: We aim at augmenting the current blazar census to build a catalog of blazar candidates with homogeneous sky coverage that can provide candidate counterparts to unassociated gamma-ray sources, sources of high-energy neutrino emission, and ultra-high energy cosmic rays. Methods: Starting from the ALMA Calibrator Catalog we built a catalog of 1580 blazar candidates (ALMA Blazar Candidates, ABC) for which we collect multi-wavelength information. We also compared ABC sources with existing blazar catalogs. Results: The ABC catalogue fills the lack of low Galactic latitude sources in current blazar catalogues. ABC sources are significantly dimmer than known blazars in Gaia g band, and they appear bluer in SDSS and WISE colors. The majority of ABC sources (~ 90%) have optical spectra that classify them as QSO, while the remaining sources resulted galactic objects. ABC sources are similar in X-rays to known blazar, while in gamma-rays they are on average dimmer and softer, indicating a significant contribution of FSRQ sources. Making use of WISE colours, we classified 715 ABC sources as candidate gamma-ray blazar of different classes. Conclusions: We built a new catalogue of 1580 candidate blazars with a rich multi-wavelength data-set, filling the lack of low Galactic latitude sources in current blazar catalogues. This will be particularly important to identify the source population of high energy neutrinos or ultra-high energy cosmic rays. The data collected by the upcoming LSST surveys will provide a key tool to investigate the possible blazar nature of these sources., 53 pages, 32 figures, 6 tables. Accepted for publication on A&A
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- 2020
24. Chandra Observations of NGC 7212: Large-scale Extended Hard X-ray Emission
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Giuseppina Fabbiano, A. Siemiginowska, Alessandro Paggi, Martin Elvis, W. P. Maksym, John C. Raymond, Margarita Karovska, and Mackenzie L. Jones
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Active galaxies ,X-ray active galactic nuclei ,AGN host galaxies ,Active galactic nucleus ,010504 meteorology & atmospheric sciences ,Astrophysics::High Energy Astrophysical Phenomena ,Continuum (design consultancy) ,FOS: Physical sciences ,Photoionization ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Ionization ,0103 physical sciences ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Supermassive black hole ,Astronomy and Astrophysics ,K-line ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Compact group ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
Recent observations of nearby Compton thick (CT) active galactic nuclei (AGNs) with Chandra have resolved hard (>3 keV) X-ray emission extending out from the central supermassive black hole to kiloparsec scales, challenging the long-held belief that the characteristic hard X-ray continuum and fluorescent Fe K lines originate in the inner ~parsec due to the excitation of obscuring material. In this paper we present the results of the most recent Chandra ACIS-S observations of NGC 7212, a CT AGN in a compact group of interacting galaxies, with a total effective exposure of ~150 ks. We find ~20 percent of the observed emission is found outside of the central ~kiloparsec, with ~17 percent associated with the soft X-rays, and ~3 percent with hard X-ray continuum and Fe K line. This emission is extended both along the ionization cone and in the cross-cone direction up to ~3.8 kpc scales. The spectrum of NGC 7212 is best represented by a mixture of thermal and photoionization models that indicate the presence of complex gas interactions. These observations are consistent with what is observed in other CT AGN (e.g., ESO 428-G014, NGC 1068), providing further evidence that this may be a common phenomenon. High-resolution observations of extended CT AGN provide an especially valuable environment for understanding how AGN feedback impacts host galaxies on galactic scales., 20 pages, 10 figures, 8 tables, Accepted for publication in ApJ
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- 2020
25. Completing the 3CR Chandra Snapshot Survey: Extragalactic Radio Sources at High Redshift
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Francesco Massaro, William R. Forman, V. Missaglia, R. P. Kraft, Joanna Kuraszkiewicz, C. P. O'Dea, C. Stuardi, Alessandro Paggi, Belinda Jane Wilkes, M. A. Prieto, Federica Ricci, D. E. Harris, A. Jimenez-Gallardo, Stefi A. Baum, Elisabetta Liuzzo, Grant R. Tremblay, Jimenez-Gallardo A., Massaro F., Prieto M.A., Missaglia V., Stuardi C., Paggi A., Ricci F., Kraft R.P., Liuzzo E., Tremblay G.R., Baum S.A., O'Dea C.P., Wilkes B.J., Kuraszkiewicz J., Forman W.R., Harris D.E., Jimenez-Gallardo, A., Massaro, F., Prieto, M. A., Missaglia, V., Stuardi, C., Paggi, A., Ricci, F., Kraft, R. P., Liuzzo, E., Tremblay, G. R., Baum, S. A., O’Dea, C. P., Wilkes, B. J., Kuraszkiewicz, J., Forman, W. R., and Harris, D. E.
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Active galactic nucleus ,Radio sources ,High-energy astronomy ,Astrophysics::High Energy Astrophysical Phenomena ,astro-ph.GA ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,High energy astrophysic ,Active galaxie ,0103 physical sciences ,010303 astronomy & astrophysics ,Physics ,astro-ph.HE ,Active galactic nuclei ,X-ray active galactic nuclei ,010308 nuclear & particles physics ,Astronomy ,Astronomy and Astrophysics ,Redshift ,Active galaxies ,High energy astrophysics ,Radio active galactic nuclei ,13. Climate action ,Space and Planetary Science ,Snapshot (computer storage) - Abstract
We present the analysis of nine radio sources belonging to the Third Cambridge Revised catalog (3CR) observed with Chandra during Cycle 20 in the redshift range between 1.5 and 2.5. This study completes the 3CR Chandra Snapshot Survey thus guaranteeing the X-ray coverage of all 3CR sources identified to date. This sample lists two compact steep spectrum sources, four radio galaxies, and three quasars. We detected X-ray emission from all nuclei, with the only exception of 3C 326.1 and 3C 454.1 and from radio lobes in six out of nine sources at a level of confidence larger than similar to 5 sigma. We measured X-ray fluxes and luminosities for all nuclei and lobes in the soft (0.5-1 keV), medium (1-2 keV), and hard (2-7 keV) X-ray bands. Since the discovered X-ray extended emission is spatially coincident with the radio structure in all cases, its origin could be due to inverse Compton (IC) scattering of the cosmic microwave background (CMB) occurring in radio lobes.
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- 2020
26. Comparing X-ray color selection in separating X-ray binary classes using Color-Color-Intensity diagrams
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Ewan O'Sullivan, A. Mossman, Jennifer Lauer, Raffaele D'Abrusco, Ginevra Trinchieri, Giuseppina Fabbiano, Douglas Morgan, Douglas Burke, Nazma Islam, Bram Boroson, C. Anderson, S. D. Vrtilek, Michael L. McCollough, Alessandro Paggi, Dong-Woo Kim, and Antonella Fruscione
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Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Stars: Black holes ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,Color intensity ,X-ray ,X-ray binary ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Compact star ,01 natural sciences ,Universality (dynamical systems) ,Black hole ,Neutron star ,Space and Planetary Science ,Methods: Data analysis ,0103 physical sciences ,Stars: Neutron ,X-rays: Binaries ,Astrophysics - High Energy Astrophysical Phenomena ,010303 astronomy & astrophysics ,Instrumentation - Abstract
X-ray binaries exhibit a wide range of properties but there are few accepted methods to determine the nature of the compact object. Color-Color-Intensity diagrams have been suggested as a means of distinguishing between systems containing black holes from those containing neutron stars. However, this technique has been verified with data from only one instrument (RXTE/ASM) with a single set of X-ray colors defined using data available only in pre-determined energy bands. We test a selection of X-ray colors with a more sensitive instrument to determine the reliability of this method. We use data from the MAXI Gas Slit Camera, which allows users to specify energy-bands. We test X-ray colors that have been previously defined in the literature as well as ones that we define specifically in this paper. A representative set of systems are used to construct Color-Color-Intensity diagrams in each set of colors to determine which are best for separating different classes. For studying individual sources certain bands are more effective than others. For a specified energy range, the separation of soft states in black hole binaries was possible only where both soft and hard colors included information from the lowest energy band. We confirm that Color-Color-Intensity diagrams can distinguish between systems containing black holes or neutron stars in all X-ray colors tested; this suggests an universality in the accretion processes governing these different classes. We suggest possible physical processes driving different classes of X-ray binaries to different locations in Color-Color-Intensity diagrams., Comment: 23 pages, 19 figures. Accepted in New Astronomy
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- 2020
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27. Optical spectroscopic observations of gamma-ray blazar candidates. X. Results from the 2018–2019 SOAR and OAN-SPM observations of blazar candidates of uncertain type
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H. A. Peña-Herazo, Raúl A. Amaya-Almazán, R. de Menezes, Alessandro Paggi, N. Masetti, Francesco Massaro, Elena Jiménez-Bailón, E. J. Marchesini, Howard A. Smith, Raffaele D'Abrusco, Dan Milisavljevic, G. Tosti, F. La Franca, C. C. Cheung, Federica Ricci, Marco Landoni, V. H. Chavushyan, de Menezes, R., Amaya-Almazan, R. A., Marchesini, E. J., Pena-Herazo, H. A., Massaro, F., Chavushyan, V., Paggi, A., Landoni, M., Masetti, N., Ricci, F., D'Abrusco, R., La Franca, F., Smith, H. A., Milisavljevic, D., Tosti, G., Jimenez-Bailon, E., Cheung, C. C., de Menezes R., Amaya-Almazan R. A., Marchesini E. J., Pena-Herazo H. A., Massaro F., Chavushyan V., Paggi A., Landoni M., Masetti N., Ricci F., D'Abrusco R., La Franca F., Smith H. A., Milisavljevic D., Tosti G., Jimenez-Bailon E., and Cheung C. C.
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active [Galaxies] ,Radiation mechanisms: non-thermal ,FOS: Physical sciences ,Galaxies: BL Lacertae objects ,Astrophysics ,Surveys ,01 natural sciences ,Galaxies: active ,Quasars: general ,law.invention ,purl.org/becyt/ford/1 [https] ,Telescope ,law ,Observatory ,0103 physical sciences ,Blazar ,010303 astronomy & astrophysics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,non-thermal [Radiation mechanisms] ,Gamma ray ,Astronomy and Astrophysics ,Quasar ,general [Quasars] ,purl.org/becyt/ford/1.3 [https] ,Galaxy ,Redshift ,Space and Planetary Science ,Galaxies: BL Lacertae object ,Astrophysics - High Energy Astrophysical Phenomena ,BL Lacertae object [Galaxies] ,BL LACERTAE OBJECTS [GALAXIES] ,Fermi Gamma-ray Space Telescope - Abstract
The fourth Fermi Large Area Telescope Source Catalog (4FGL) lists over 5000 gamma-ray sources with statistical significance above 4$\sigma$. About 23% of the sources listed in this catalog are unidentified/unassociated gamma-ray sources while ~26% of the sources are classified as blazar candidates of uncertain type (BCUs), lacking optical spectroscopic information. To probe the blazar nature of candidate counterparts of UGSs and BCUs, we started our optical spectroscopic follow up campaign in 2012, which up to date account for more than 350 observed sources. In this paper, the tenth of our campaign, we report on the spectroscopic observations of 37 sources, mostly BCUs, whose observations were carried out predominantly at the Observatorio Astron\'omico Nacional San Pedro M\'artir and the Southern Astrophysical Research Observatory between August 2018 and September 2019. We confirm the BL Lac nature of 27 sources and the flat spectrum radio quasar nature of three sources. The remaining ones are classified as six BL Lacs galaxy-dominated and one normal galaxy. We were also able to measure the redshifts for 20 sources, including 10 BL Lacs. As in previous analyses, the largest fraction of BCUs revealed to be BL Lac objects., Comment: 24 pages, 14 figures, 3 tables (Pre-proof version)
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- 2020
28. The Imaging X-ray polarimetry explorer (IXPE): Technical overview III
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Paolo Soffitta, Primo Attina', Luca Baldini, Mattia Barbanera, Wayne H. Baumgartner, Ronaldo Bellazzini, Jeff Bladt, Stephen D. Bongiorno, Alessandro Brez, Simone Castellano, Rita Carpentiero, Marco Castronuovo, Luca Cavalli, Elisabetta Cavazzuti, Fabio D' Amico, Saverio Citraro, Enrico Costa, William D. Deininger, ELisa D' Alba, Ettore Del Monte, Kutis L. Diets, Niccolo' Di Lalla, Alessandro Di Marco, Guseppe Di Persio, Immacolata Donnarumma, Ronald F. Elsner, Sergio Fabiani, Riccardo Ferrazzoli, Larry Guy, William Kalinowski, Jeffery Kolodziejczak, Luca Latronico, Carlo Lefevre, Paolo Lorenzi, Leonardo Lucchesi, Simone Maldera, Alberto Manfreda, Elio Mangraviti, Herman L. Marshall, James Masciarelli, Giorgio Matt, Massimo Minuti, Fabio Muleri, Hikmat Nasimi, Barbara Negri, Alessio Nuti, Leonardo Orsini, Darren Osborne, Maura Pilia, Matteo Perri, Melissa Pesce-Rollins, Colin Peterson, Michele Pinchera, Simonetta Puccetti, Brian Ramsey, Ajay Ratheesh, Roger W. Romani, Paolo Sarra, Francesco Santoli, Andrea Sciortino, Carmelo Sgro', Brian T. Smith, Gloria Spandre, Allyn F. Tennant, Antonino Tobia, Alessio Trois, Marco Vimercati, Jeffrey Wedmnore, Martin C. Weisskopf, Fei Xie, Francesco Zanetti, Cheryl Alexander, D. Zachery Allen, Fabrizio Amici, L. Angelo Antonelli, Spencer Antoniak, Matteo Bachetti, Raffaella Bonino, Fabio Borotto, Shawn Breeding, Daniele Brienza, H. Kyle Bygott, Claudia Cardelli, Marco Ceccanti, Mauro Centrone, Yuri Evangelista, MacKenzie Ferrie, Brent Forsyth, Michele Foster, Eli Gurnee, Grant Hibbard, Sandra R. Johnson, Erik Kelly, Kiranmayee Kilaru, Fabio La Monaca, Shelley Le Roy, Pasqualino Loffredo, Guido Magazzu', Marco Marengo, Alessandra Marrocchesi, Francesco Massaro, Alfredo Morbidini, Jeffrey McCracken, Michael McEachen, Paolo Mereu, Scott Mitchell, Ikuyuki Mitsuishi, Federico Mosti, Michela Nigro, Chiara Oppedisano, Richard Pacheco, alessandro Paggi, Steven D. Pavelitz, Cristina Pentz, Raffaele Piazzolla, Brad Porter, Alessandro Profeti, Jaganathan Ranganathan, John Rankin, Noah Root, Alda Rubini, Stephanie Ruswick, Javier Sanchez, Emanuele Scalise, Sara Schindhelm, Chet O. Speegle, Toru Tamagawa, Marcello Tardiola, Amy L. Walden, Bruce Weddendorf, David Welch, Michael Head, Stuart Gray, Rondal Mize, Stephen L. O'Dell, Christopher Schroeder, Nicholas E. Thomas, Randy M. Bagget, David Dolan, Kevin Ferrant, Joseph Footdale, Benjamin Garelick, Samantha Johnson, and Timothy Seek
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Physics ,X-ray ,Optics ,business.industry ,X-ray, Polarimetry, Astrophysics, Optics, Gas Pixel Detector ,Polarimetry ,business ,Astrophysics ,Gas Pixel Detector - Published
- 2020
29. Optical spectroscopic observations of low-energy counterparts of Fermi -LAT γ -ray sources
- Author
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H. A. Peña-Herazo, C. C. Cheung, Raúl A. Amaya-Almazán, G. Tosti, Francesco Massaro, R. de Menezes, R. D'Abrusco, Elena Jiménez-Bailón, Alessandro Paggi, Howard A. Smith, Marco Landoni, V. H. Chavushyan, F. Ricci, Dan Milisavljevic, E. J. Marchesini, N. Masetti, Víctor M. Patiño-Álvarez, F. La Franca, Pena-Herazo H. A., Amaya-Almazan R. A., Massaro F., De Menezes R., Marchesini E. J., Chavushyan V., Paggi A., Landoni M., Masetti N., Ricci F., D'Abrusco R., Cheung C. C., La Franca F., Smith H. A., Milisavljevic D., Jimenez-Bailon E., Patino-Alvarez V. M., Tosti G., Pena-Herazo, H. A., Amaya-Almazan, R. A., Massaro, F., De Menezes, R., Marchesini, E. J., Chavushyan, V., Paggi, A., Landoni, M., Masetti, N., Ricci, F., D'Abrusco, R., Cheung, C. C., La Franca, F., Smith, H. A., Milisavljevic, D., Jimenez-Bailon, E., Patino-Alvarez, V. M., and Tosti, G.
- Subjects
luminosity function, mass function [Galaxies] ,active [Galaxies] ,media_common.quotation_subject ,Population ,FOS: Physical sciences ,Astrophysics ,01 natural sciences ,law.invention ,Telescope ,emission lines [Quasars] ,Low energy ,law ,Galaxies: luminosity function ,0103 physical sciences ,Blazar ,education ,010303 astronomy & astrophysics ,media_common ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,education.field_of_study ,Quasars: emission lines ,general [BL Lacertae objects] ,010308 nuclear & particles physics ,Gamma ray ,Astronomy and Astrophysics ,BL Lacertae objects: general ,Galaxies: active ,Space and Planetary Science ,Sky ,mass function ,Astrophysics - High Energy Astrophysical Phenomena ,Data release ,Fermi Gamma-ray Space Telescope - Abstract
A significant fraction of all $\gamma$-ray sources detected by the Large Area Telescope aboard the \fer\ satellite is still lacking a low-energy counterpart. In addition, there is still a large population of $\gamma$-ray sources with associated low-energy counterparts that lack firm classifications. In the last 10 years we have undertaken an optical spectroscopic campaign to address the problem of unassociated/unidentified $\gamma$-ray sources (UGSs), mainly devoted to observing blazars and blazar candidates because they are the largest population of $\gamma$-ray sources associated to date. Here we describe the overall impact of our optical spectroscopic campaign on sources associated in \fer-LAT catalogs, coupled with objects found in the literature. In the literature search, we kept track of efforts by different teams that presented optical spectra of counterparts or potential counterparts of \fer-LAT catalog sources. Our summary includes an analysis of an additional 30 newly-collected optical spectra of counterparts or potential counterparts of \fer-LAT sources of previously unknown nature.New spectra were acquired at the Blanco 4-m and OAN-SPM 2.1-m telescopes, and those available in the Sloan Digital Sky Survey (data release 15) archive. All new sources with optical spectra analyzed here are classified as blazars. Thanks to our campaign, we altogether discovered and classified 394 targets with an additional 123 objects collected from a literature search. We began our optical spectroscopic campaign between the release of the second and third \fer-LAT source catalogs (2FGL and 3FGL, respectively), and classified about 25\% of the sources with uncertain nature and discovered a blazar-like potential counterpart for $\sim$10\% of UGSs listed therein. In the 4FGL catalog, about 350 \fer-LAT sources are classified to date thanks to our campaign. [incomplete abstract], Comment: 31 pages, 12 tables, 32 figures, 2 appendices, accepted for publication on A&A (pre-proofs version)
- Published
- 2020
30. An XMM-Newton Early-type Galaxy Atlas
- Author
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Amy E. Mossman, Ewan O'Sullivan, Craig Anderson, Ginevra Trinchieri, Alessandro Paggi, Giuseppina Fabbiano, Nazma Islam, Kenneth Lin, Saeqa Dil Vrtilek, Jennifer Lauer, Dong-Woo Kim, and Douglas Morgan
- Subjects
Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Astronomy & Astrophysics ,Atomic ,Particle and Plasma Physics ,Atlas (anatomy) ,medicine ,Nuclear ,Astrophysics::Galaxy Astrophysics ,Physics ,Astrophysical Processes ,Conjunction (astronomy) ,Spatially resolved ,Molecular ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Early type ,Interstellar medium ,medicine.anatomical_structure ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,Halo ,Astronomical and Space Sciences ,Physical Chemistry (incl. Structural) - Abstract
The distribution of hot interstellar medium in early-type galaxies bears the imprint of the various astrophysical processes it underwent during its evolution. The X-ray observations of these galaxies have identified various structural features related to AGN and stellar feedback and environmental effects such as merging and sloshing. In our XMM-Newton Galaxy Atlas (NGA) project, we analyze archival observations of 38 ETGs, utilizing the high sensitivity and large field of view of XMM-Newton to construct spatially resolved 2D spectral maps of the hot gas halos. To illustrate our NGA data products in conjunction with the Chandra Galaxy Atlas (Kim et al. 2019), we describe two distinct galaxies - NGC 4636 and NGC 1550, in detail. We discuss their evolutionary history with a particular focus on the asymmetric distribution of metal-enriched, low-entropy gas caused by sloshing and AGN- driven uplift. We will release the NGA data products to a dedicated website, which users can download to perform further analyses., 19 pages, 6 figures, 2 tables. Accepted for publication in ApJS. The data-products along with the quick look results are here: https://cxc.cfa.harvard.edu/GalaxyAtlas/NGA/v1/
- Published
- 2021
31. Optical spectroscopic observations of gamma-ray blazar candidates. IX. Optical archival spectra and further observations from SOAR and OAGH
- Author
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Marco Landoni, Dan Milisavljevic, Alessandro Paggi, H. A. Peña-Herazo, Raffaele D'Abrusco, V. H. Chavushyan, F. La Franca, Federica Ricci, Gino Tosti, Francesco Massaro, Elena Jiménez-Bailón, E. J. Marchesini, N. Masetti, Howard A. Smith, Peña-Herazo, H. A., Massaro, F., Chavushyan, V., Marchesini, E. J., Paggi, A., Landoni, M., Masetti, N., Ricci, F., D’Abrusco, R., Milisavljevic, D., Jiménez-Bailón, E., La Franca, F., Smith, Howard A., and Tosti, G.
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Active galactic nucleus ,active [Galaxies] ,Radiation mechanisms: non-thermal ,media_common.quotation_subject ,Population ,FOS: Physical sciences ,Galaxies: BL Lacertae objects ,Astrophysics ,Surveys ,Galaxies: active ,Quasars: general ,01 natural sciences ,Cosmology ,Observatory ,0103 physical sciences ,Survey ,Blazar ,education ,010303 astronomy & astrophysics ,media_common ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,education.field_of_study ,non-thermal [Radiation mechanisms] ,Gamma ray ,general [Quasars] ,Astronomy and Astrophysics ,Quasar ,Astrophysics - Astrophysics of Galaxies ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) ,Galaxies: BL Lacertae object ,Astrophysics - High Energy Astrophysical Phenomena ,BL Lacertae object [Galaxies] - Abstract
Nearly one-third of the sources in the $Fermi$-LAT catalogs lack a lower energy counterpart, hence being referred as unidentified/unassociated gamma-ray sources (UGSs). In order to firmly classify them, dedicated multifrequency follow-up campaigns are necessary. These will permit to unveil their nature and identify the fraction that could belong to the class of active galaxies known as blazars that is the largest population of extragalactic $\gamma$-ray sources. In $Fermi$-LAT catalogs there are also gamma-ray sources associated with multifrequency blazar-like objects known as Blazars Candidates of Uncertain type (i.e., BCUs) for which follow up spectroscopic campaigns are mandatory to confirm their blazar nature. Thus, in 2013 we started an optical spectroscopic campaign to identify blazar-like objects potential counterparts of UGSs and BCUs. Here we report the spectra of 31 additional targets observed as part of our follow up campaign. Thirteen of them are BCUs for which we acquired spectroscopic observations at Observatorio Astrof\'isico Guillermo Haro (OAGH) and at Southern Astrophysical Research Observatory (SOAR) telescopes, while the rest has been identified thanks to the archival observations available from the Sloan Digital Sky Survey (SDSS). We confirm the blazar nature of all BCUs: three of them are in blazar of quasar type (BZQs) while the remaining ones can be spectroscopically classified as BL Lac objects (BZBs). Then we also discovered 18 BL Lac objects lying within the positional uncertainty regions of UGSs that could be their potential counterparts., Comment: 30 pages and 65 figures
- Published
- 2019
32. The γ-ray sky seen at X-ray energies. I. Searching for the connection between X-rays and γ-rays in Fermi BL Lac objects
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Ileana Andruchow, N. Masetti, Francesco Massaro, Raffaele D'Abrusco, E. J. Marchesini, Alessandro Paggi, and R. de Menezes
- Subjects
Active galactic nucleus ,010504 meteorology & atmospheric sciences ,Infrared ,GALAXIES [GAMMA RAYS] ,Astrophysics::High Energy Astrophysical Phenomena ,Population ,Context (language use) ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,law.invention ,purl.org/becyt/ford/1 [https] ,law ,GALAXIES [X-RAYS] ,0103 physical sciences ,GENRAL [BL LACERTAE OBJECTSS] ,education ,Blazar ,010303 astronomy & astrophysics ,ACTIVE [GALAXIES] ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Physics ,education.field_of_study ,JETS [GALAXIES] ,Astronomy and Astrophysics ,purl.org/becyt/ford/1.3 [https] ,Astrophysics - Astrophysics of Galaxies ,Synchrotron ,Space and Planetary Science ,Spectral energy distribution ,Astrophysics - High Energy Astrophysical Phenomena ,Fermi Gamma-ray Space Telescope - Abstract
BL Lac objects are an extreme type of active galactic nuclei (AGNs) that belong to the largest population of $\gamma$-ray sources: blazars. This class of AGNs shows a double-bumped spectral energy distribution that is commonly described in terms of a synchrotron self-Compton (SSC) emission process, whereas the low-energy component that dominates their emission between the infrared and the X-ray band is tightly connected to the high-energy component that peaks in the $\gamma$-rays. Two strong connections that link radio and mid-infrared emission of blazars to the emission in the $\gamma$-ray band are well established. They constitute the basis for associating $\gamma$-ray sources with their low-energy counterparts. We searched for a possible link between X-ray and $\gamma$-ray emissions for the subclass of BL Lacs using all archival Swift/XRT observations combined with Fermi data for a selected sample of 351 sources. Analyzing $\sim$2400 ks of Swift/XRT observations that were carried out until December 2018, we discovered that above the $\gamma$-ray flux threshold $F_{\gamma}\approx3\times10^{-12}\,\rm{erg}\,\rm{cm}^{-2}\,\rm{s}^{-1}$, 96\% of all \emph{Fermi} BL Lacs have an X-ray counterpart that is detected with signal-to-noise ratio higher than 3. We did not find any correlation or clear trend between X-ray and $\gamma$-ray fluxes and/or spectral shapes, but we discovered a correlation between the X-ray flux and the mid-infrared color. Finally, we discuss on a possible interpretation of our results in the SSC framework., Comment: 12 pages, 15 figures, 1 table (pre-proof version), A&A published
- Published
- 2019
33. COMP2CAT: hunting compact double radio sources in the local Universe
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Aneta Siemiginowska, Alessandro Capetti, M. A. Prieto, S. Viada, Francesco Massaro, Ranieri D. Baldi, A. Jimenez-Gallardo, Alessandro Paggi, R. Grossova, and Luisa Ostorero
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High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,010308 nuclear & particles physics ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,catalogs – galaxies: active – galaxies: jets – galaxies: general ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Universe ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Astrophysics - High Energy Astrophysical Phenomena ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common - Abstract
We present a catalog of compact double radio galaxies (hereafter COMP2CAT) listing 43 edge-brightened radio sources whose projected linear size does not exceed 60 kpc, the typical size of their host galaxies. This is the fifth in a series of radio source catalogs recently created, namely: FRICAT, FRIICAT, FR0CAT, and WATCAT, each of which focuses on a different class of radio galaxies. The main aim of our analysis is to attain a better understanding of sources with intermediate morphologies between FR IIs and FR 0s. COMP2CAT sources were selected from an existing catalog of radio sources based on NVSS, FIRST and SDSS observations because they have (i) edge-brightened morphologies typical of FR IIs, (ii) redshifts z < 0.15, and (iii) projected linear sizes smaller than 60 kpc. With radio luminosities at 1.4 GHz 1038 ≲ L1.4 ≲ 1041 erg s−1, COMP2CAT sources appear as the low radio luminosity tail of FR IIs. However, their host galaxies are indistinguishable from those of large-scale radio sources: they are luminous (−21 ≳ Mr ≳ −24), red, early-type galaxies with black hole masses in the range 107.5 ≲ MBH ≲ 109.5 M⊙. Moreover, all but one of the COMP2CAT sources are optically classifiable as low-excitation radio galaxies, in agreement with being the low radio luminosity tail of FR Is and FR IIs. This catalog of compact double sources, which is ∼47% complete at z < 0.15, can potentially be used to clarify the role of compact double sources in the general evolutionary scheme of radio galaxies.
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- 2019
34. WATCAT: a tale of wide-angle tailed radio galaxies
- Author
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Maurizio Paolillo, Alessandro Paggi, Ranieri D. Baldi, Francesco Massaro, V. Missaglia, Ralph P. Kraft, Alessandro Capetti, Missaglia, V., Massaro, F., Capetti, A., Paolillo, M., Kraft, R. ~P., Baldi, R. ~D., and Paggi, A.
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Radio galaxy ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,galaxies: active ,FOS: Physical sciences ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,0103 physical sciences ,galaxies: active, galaxies: jets, radio continuum: galaxies, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Very large array ,Physics ,radio continuum: galaxies ,010308 nuclear & particles physics ,Astrophysics::Instrumentation and Methods for Astrophysics ,Astronomy and Astrophysics ,galaxies: jets ,Radio astronomy observatory ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Redshift ,Black hole ,Space and Planetary Science ,Sky ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present a catalog of 47 wide-angle tailed radio galaxies (WATs), the WATCAT, mainly built including a radio morphological classification; WATs were selected by combining observations from the National Radio Astronomy Observatory/Very Large Array Sky Survey (NVSS), the Faint Images of the Radio Sky at Twenty-Centimeters (FIRST), and the Sloan Digital Sky Survey (SDSS). We included in the catalog only radio sources showing two-sided jets with two clear “warmspots” (i.e., jet knots as bright as 20% of the nucleus) lying on the opposite side of the radio core, and having classical extended emission resembling a plume beyond them. The catalog is limited to redshifts z ≤ 0.15, and lists only sources with radio emission extended beyond 30 kpc from the host galaxy. We found that host galaxies of WATCAT sources are all luminous (−20.5 ≳ Mr ≳ −23.7), red early-type galaxies with black hole masses in the range 108 ≲ MBH ≲ 109 M⊙. The spectroscopic classification indicates that they are all low-excitation galaxies (LEGs). Comparing WAT multifrequency properties with those of FR I and FR II radio galaxies at the same redshifts, we conclude that WATs show multifrequency properties remarkably similar to FR I radio galaxies, having radio power of typical FR IIs.
- Published
- 2019
35. Two years of non-thermal emission from the binary neutron star merger GW170817: rapid fading of the jet afterglow and first constraints on the kilonova fastest ejecta
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Matt Nicholl, Andrew MacFadyen, Edo Berger, X. Xie, Dimitrios Giannios, Kate D. Alexander, Brian D. Metzger, David Radice, Philip S. Cowperthwaite, Tarraneh Eftekhari, Giacomo Terreran, Yiyang Wu, Wen-fai Fong, C. Guidorzi, Ryan Chornock, Alessandro Paggi, Griffin Hosseinzadeh, Sebastian Gomez, Deanne L. Coppejans, Kerry Paterson, P. K. Blanchard, Tanmoy Laskar, Jonathan Zrake, V. A. Villar, Raffaella Margutti, A. Baldeschi, A. Kathirgamaraju, A. Hajela, Lorenzo Sironi, and Peter K. G. Williams
- Subjects
Radio transient sources ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Binary number ,Socio-culturale ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,Kilonova ,Diffuse x-ray background ,01 natural sciences ,Neutron stars ,0103 physical sciences ,Fading ,010306 general physics ,Ejecta ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Physics ,Jet (fluid) ,Gamma-ray bursts, Neutron stars, X-ray transient sources, Diffuse x-ray background, Radio transient sources ,X-ray transient sources ,Astronomy and Astrophysics ,Afterglow ,Neutron star ,Space and Planetary Science ,Gamma-ray bursts ,Astrophysics - High Energy Astrophysical Phenomena ,Gamma-ray burst - Abstract
We present Chandra and VLA observations of GW170817 at ~521-743 days post merger, and a homogeneous analysis of the entire Chandra data set. We find that the late-time non-thermal emission follows the expected evolution from an off-axis relativistic jet, with a steep temporal decay $F_{\nu}\propto t^{-1.95\pm0.15}$ and a simple power-law spectrum $F_{\nu}\propto \nu^{-0.575\pm0.007}$. We present a new method to constrain the merger environment density based on diffuse X-ray emission from hot plasma in the host galaxy and we find $n\le 9.6 \times 10^{-3}\,\rm{cm^{-3}}$. This measurement is independent from inferences based on the jet afterglow modeling and allows us to partially solve for model degeneracies. The updated best-fitting model parameters with this density constraint are a fireball kinetic energy $E_0 = 1.5_{-1.1}^{+3.6}\times 10^{49}\,\rm{erg}$ ($E_{iso}= 2.1_{-1.5}^{+6.4}\times10^{52}\, \rm{erg}$), jet opening angle $\theta_{0}= 5.9^{+1.0}_{-0.7}\,\rm{deg}$ with characteristic Lorentz factor $\Gamma_j = 163_{-43}^{+23}$, expanding in a low-density medium with $n_0 = 2.5_{-1.9}^{+4.1} \times 10^{-3}\, \rm{cm^{-3}}$ and viewed $\theta_{obs} = 30.4^{+4.0}_{-3.4}\, \rm{deg}$ off-axis. The synchrotron emission originates from a power-law distribution of electrons with $p=2.15^{+0.01}_{-0.02}$. The shock microphysics parameters are constrained to $\epsilon_{\rm{e}} = 0.18_{-0.13}^{+0.30}$ and $\epsilon_{\rm{B}}=2.3_{-2.2}^{+16.0} \times 10^{-3}$. We investigate the presence of X-ray flares and find no statistically significant evidence of $\ge2.5\sigma$ of temporal variability at any time. Finally, we use our observations to constrain the properties of synchrotron emission from the deceleration of the fastest kilonova ejecta with energy $E_k^{KN}\propto (\Gamma\beta)^{-\alpha}$ into the environment, finding that shallow stratification indexes $\alpha\le6$ are disfavored., Comment: version accepted for publication in ApJL, 13 pages, 6 figures
- Published
- 2019
36. Optical characterization of WISE selected blazar candidates
- Author
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Marco Landoni, Raniere de Menezes, Howard A. Smith, E. J. Marchesini, Alessandro Paggi, N. Masetti, Raffaele D'Abrusco, Federica Ricci, Francesco Massaro, H. A. Peña-Herazo, Rodrigo Nemmen, de Menezes, Raniere, Peña-Herazo, Harold A., Marchesini, Ezequiel J., D'ABRUSCO, Raffaele, Masetti, Nicola, Nemmen, Rodrigo, Massaro, Francesco, RICCI, FEDERICA, Landoni, Marco, Paggi, Alessandro, Smith, Howard A., D’Abrusco, Raffaele, and Ricci, Federica
- Subjects
catalog ,RADIATION MECHANISMS ,BL Lacertae objects: general – catalogs – galaxies: active – radiation mechanisms: non-thermal ,Point source ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,GENERAL ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,law.invention ,Telescope ,purl.org/becyt/ford/1 [https] ,Spitzer Space Telescope ,RAIOS GAMA ,law ,0103 physical sciences ,ACTIVE ,Blazar ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,media_common ,Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,CATALOGS ,010308 nuclear & particles physics ,general [BL Lacertae objects] ,Astronomy and Astrophysics ,Quasar ,purl.org/becyt/ford/1.3 [https] ,non-thermal [radiation mechanisms] ,Galaxy ,GALAXIES ,Space and Planetary Science ,Sky ,active [galaxies] ,NON-THERMAL ,BL LACERTAE OBJECTS ,Astrophysics - High Energy Astrophysical Phenomena ,Fermi Gamma-ray Space Telescope - Abstract
Over the last decade more than five thousand gamma-ray sources were detected by the Large Area Telescope (LAT) on board Fermi Gamma-ray Space Telescope. Given the positional uncertainty of the telescope, nearly 30% of these sources remain without an obvious counterpart in lower energies. This motivated the release of new catalogs of gamma-ray counterpart candidates and several follow up campaigns in the last decade. Recently, two new catalogs of blazar candidates were released, they are the improved and expanded version of the WISE Blazar-Like Radio-Loud Sources (WIBRaLS2) catalog and the Kernel Density Estimation selected candidate BL Lacs (KDEBLLACS) catalog, both selecting blazar-like sources based on their infrared colors from the Wide-field Infrared Survey Explorer (WISE). In this work we characterized these two catalogs, clarifying the true nature of their sources based on their optical spectra from SDSS data release 15, thus testing how efficient they are in selecting true blazars. We first selected all WIBRaLS2 and KDEBLLACS sources with available optical spectra in the footprint of Sloan Digital Sky Survey data release 15. Then we analyzed these spectra to verify the nature of each selected candidate and see which fraction of the catalogs is composed by spectroscopically confirmed blazars. Finally, we evaluated the impact of selection effects, specially those related to optical colors of WIBRaLS2/KDEBLLACS sources and their optical magnitude distributions. We found that at least ~ 30% of each catalog is composed by confirmed blazars, with quasars being the major contaminants in the case of WIBRaLS2 (~ 58%) and normal galaxies in the case of KDEBLLACS (~ 38.2%). The spectral analysis also allowed us to identify the nature of 11 blazar candidates of uncertain type (BCUs) from the Fermi-LAT 4th Point Source Catalog (4FGL) and to find 25 new BL Lac objects., 11 pages, 11 figures
- Published
- 2019
37. X-ray Photons in the CO 2-1 'Lacuna' of NGC 2110
- Author
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Alessandro Paggi, Martin Elvis, and Giuseppina Fabbiano
- Subjects
Galaxies: Seyfert ,X-rays: Individual (NGC 2110 ,Active galactic nucleus ,Photon ,010504 meteorology & atmospheric sciences ,X-rays: Galaxies ,FOS: Physical sciences ,Astrophysics ,01 natural sciences ,0103 physical sciences ,medicine ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,X ray photons ,Molecular cloud ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,medicine.anatomical_structure ,Space and Planetary Science ,Excited state ,Astrophysics of Galaxies (astro-ph.GA) ,Astrophysics - High Energy Astrophysical Phenomena ,Nucleus ,Excitation - Abstract
A recent ALMA study of the Seyfert 2 Active Galactic Nucleus (AGN) NGC 2110 by Rosario et al. (2019) has reported a remarkable lack of CO 2-1 emission from the circumnuclear region, where optical lines and H2 emission are observed, leading to the suggestion of excitation of the molecular clouds by the AGN. Since interaction with X-ray photons could be the cause of this excitation, we have searched the archival Chandra data for corroborating evidence. We report an extra-nuclear ~1'' (~170 pc) feature found in the soft (, ApJ Letters - in press
- Published
- 2019
- Full Text
- View/download PDF
38. Temperature Profiles of Hot Gas In Early Type Galaxies
- Author
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Saeqa Dil Vrtilek, Antonella Fruscione, Ewan O'Sullivan, Dong-Woo Kim, Jennifer Lauer, Raffaele D'Abrusco, Liam Traynor, Ginevra Trinchieri, A. Mossman, Douglas L. Morgan, Craig Anderson, Douglas Burke, Alessandro Paggi, Michael L. McCollough, and Giuseppina Fabbiano
- Subjects
Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,010308 nuclear & particles physics ,Star formation ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Radius ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Virial theorem ,Galaxy ,Core (optical fiber) ,Gravitation ,Temperature gradient ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Halo ,Astrophysics::Earth and Planetary Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
Using the data products of the Chandra Galaxy Atlas (Kim et al. 2019a), we have investigated the radial profiles of the hot gas temperature in 60 early type galaxies. Considering the characteristic temperature and radius of the peak, dip, and break (when scaled by the gas temperature and virial radius of each galaxy), we propose a universal temperature profile of the hot halo in ETGs. In this scheme, the hot gas temperature peaks at RMAX = 35 +/- 25 kpc (or ~0.04 RVIR) and declines both inward and outward. The temperature dips (or breaks) at RMIN (or RBREAK) = 3 - 5 kpc (or ~0.006 RVIR). The mean slope between RMIN (RBREAK) and RMAX is 0.3 +/- 0.1. Allowing for selection effects and observational limits, we find that the universal temperature profile can describe the temperature profiles of 72% (possibly up to 82%) of our ETG sample. The remaining ETGs (18%) with irregular or monotonically declining profiles do not fit the universal profile and require another explanation. The temperature gradient inside RMIN (RBREAK) varies widely, indicating different degrees of additional heating at small radii. Investigating the nature of the hot core (HC with a negative gradient inside RMIN), we find that HC is most clearly visible in small galaxies. Searching for potential clues associated with stellar, AGN feedback, and gravitational heating, we find that HC may be related to recent star formation. But we see no clear evidence that AGN feedback and gravitational heating play any significant role for HC., Comment: 36 pages, 11 figures, accepted or publication in MNRAS
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- 2019
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39. Deep Chandra Observations of ESO 428-G014: IV. The Morphology of the Nuclear Region in the Hard Continuum and Fe K{\alpha} Line
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Margarita Karovska, Martin Elvis, Aneta Siemiginowska, W. P. Maksym, Alessandro Paggi, G. Fabbiano, Marta Volonteri, Lucio Mayer, Junfeng Wang, Guido Risaliti, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, Università degli studi di Torino (UNITO), Istituto Nazionale di Fisica Nucleare, Sezione di Torino (INFN, Sezione di Torino), Istituto Nazionale di Fisica Nucleare (INFN), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Universität Zürich [Zürich] = University of Zurich (UZH), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), Xiamen University, and University of Zurich
- Subjects
Active galactic nucleus ,010504 meteorology & atmospheric sciences ,530 Physics ,Point source ,media_common.quotation_subject ,Astrophysics::High Energy Astrophysical Phenomena ,galaxies: active ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Bicone ,1912 Space and Planetary Science ,Light echo ,0103 physical sciences ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,media_common ,Physics ,Continuum (measurement) ,Astronomy and Astrophysics ,Torus ,Astrophysics - Astrophysics of Galaxies ,Accretion (astrophysics) ,galaxies: Seyfert ,X-rays: galaxies ,[PHYS.ASTR.GA]Physics [physics]/Astrophysics [astro-ph]/Galactic Astrophysics [astro-ph.GA] ,13. Climate action ,Space and Planetary Science ,Sky ,10231 Institute for Computational Science ,3103 Astronomy and Astrophysics - Abstract
We report the results of high-resolution subpixel imaging of the hard continuum and Fe K{\alpha} line of the Compton Thick (CT) Active Galactic Nucleus (AGN) ESO 428-G014, observed with Chandra ACIS. While the 3-4 keV emission is dominated by an extended component, a single nuclear point source is prominent in the 4-6 keV range. Instead, two peaks of similar intensity, separated by ~36 pc in projection on the plane of the sky are detected in the Fe K{\alpha} emission. The SE knot could be marginally associated with the heavily obscured hard continuum source. We discuss four possible interpretations of the nuclear morphology. (1) Given the bolometric luminosity and likely black hole (BH) mass of ESO 428-G014, we may be imaging two clumps of the CT obscuring torus in the Fe K{\alpha} line. (2) The Fe K{\alpha} knots may be connected with the fluorescent emission from the dusty bicone, or (3) with the light echo of a nuclear outburst. (4) We also explore the less likely possibility that we may be detecting the rare signature of merging nuclei. Considering the large-scale kpc-size extent of the hard continuum and Fe K{\alpha} emission (Papers I and II), we conclude that the AGN in ESO 428-G014 has been active for at least 104 yrs. Comparison with the models of Czerny et al (2009) suggests high accretion rates during this activity., Comment: ApJ in press
- Published
- 2018
40. Peering into the extended X-ray emission on megaparsec scale in 3C 187
- Author
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V. Missaglia, Alessandro Paggi, Francesco Massaro, Stefi A. Baum, Grant R. Tremblay, Ralph Kraft, H. A. Peña-Herazo, Federica Ricci, C. Stuardi, Belinda Jane Wilkes, Paggi, A, Massaro, F, Pena-Herazo, Ha, Missaglia, V, Ricci, F, Stuardi, C, Kraft, Rp, Tremblay, Gr, Baum, Sa, Wilkes, Bj, Paggi A., Massaro F., Pena-Herazo H.A., Missaglia V., Ricci F., Stuardi C., Kraft R.P., Tremblay G.R., Baum S.A., and Wilkes B.J.
- Subjects
010504 meteorology & atmospheric sciences ,Radio galaxy ,Galaxies: active ,Galaxies: individual: 3C 187 ,ISM: jets and outflows ,X-rays: ISM ,Astrophysics::High Energy Astrophysical Phenomena ,Cosmic microwave background ,FOS: Physical sciences ,Flux ,Context (language use) ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Spectral line ,0103 physical sciences ,ISM [X-rays] ,ISM: jets and outflow ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Galaxy cluster ,0105 earth and related environmental sciences ,Physics ,jets and outflow [ISM] ,Compton scattering ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Galaxy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,active [galaxies] ,individual: 3C 187 [galaxies] - Abstract
Context. The diffuse X-ray emission surrounding radio galaxies is generally interpreted either as due to inverse Compton scattering of non-thermal radio-emitting electrons on the Cosmic Microwave Background (IC/CMB), or as the thermal emission arising from the hot gas of the intergalactic medium (IGM) permeating galaxy clusters hosting such galaxies, or as a combination of both. In this work we present an imaging and spectral analysis of Chandra observations for the radio galaxy 3C 187 to investigate its diffuse X-ray emission and constrain the contribution of these different physical mechanisms. Aims. The main goals of this work are: (i) to evaluate the extension of the diffuse X-ray emission from this source, (ii) to investigate the two main processes that can account for its origin - IC/CMB and thermal emission from the IGM - and (iii) to test the possibility for 3C 187 to belong to a cluster of galaxies, that can account for the observed diffuse X-ray emission. Methods. To evaluate the extension of the X-ray emission around 3C 187 we extracted surface flux profiles along and across the radio axis. We also extracted X-ray spectra in the region of the radio lobes and in the cross-cone region to estimate the contribution of the non-thermal (IC/CMB) and thermal (IGM) processes to the observed emission, making use of radio (VLA and GMRT) data to investigate the multi-wavelength emission arising from the lobes. We collected Pan-STARRS photometric data to investigate the presence of a galaxy cluster hosting 3C 187, looking for the presence of a "red sequence" in the source field in the form of a tight clustering of the galaxies in the color space..., 32 pages, 13 figures, accepted for publication on A&A on 12/19/2020
- Published
- 2021
41. Dragon’s Lair: On the Large-scale Environment of BL Lac Objects
- Author
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Alessandro Paggi, Ranieri D. Baldi, Andrea Tramacere, Francesco Massaro, Alessandro Capetti, Ignazio Pillitteri, and Riccardo Campana
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Physics ,Supermassive black hole ,education.field_of_study ,Active galactic nucleus ,010504 meteorology & atmospheric sciences ,Radio galaxy ,Astrophysics::High Energy Astrophysical Phenomena ,Population ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Accretion (astrophysics) ,Luminosity ,Astrophysical jet ,Space and Planetary Science ,0103 physical sciences ,education ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Galaxy cluster ,0105 earth and related environmental sciences - Abstract
The most elusive and extreme sub-class of active galactic nuclei (AGNs), known as BL Lac objects, shows features that can only be explained as the result of relativistic effects occurring in jets pointing at a small angle with respect to the line of sight. A long standing issue is the identification of the BL Lac parent population, having jets oriented at larger angles. According to the "unification scenario" of AGNs, radio galaxies with low luminosity and edge-darkened radio morphology are the most promising candidates to be the parent population of BL Lacs. Here we compare the large-scale environment, an orientation independent property, of well-defined samples of BL Lacs with samples of radio-galaxies all lying in the local Universe. Our study reveals that BL Lacs and radio galaxies live in significantly different environments, challenging predictions of the unification scenario. We propose a solution to this problem proving that large-scale environments of BL Lacs is statistically consistent with that of compact radio-sources, known as FR0s, sharing similar properties. This implies that highly relativistic jets are ubiquitous and are the natural outcome of the accretion of gas into the deep gravitational potential well produced by supermassive black holes.
- Published
- 2020
42. Stormy weather in 3C 196.1: nuclear outbursts and merger events shape the environment of the hybrid radio galaxy 3C 196.1
- Author
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Ralph Kraft, Elisabetta Liuzzo, Francesco Massaro, Grant R. Tremblay, Stefi A. Baum, William R. Forman, Alessandro Paggi, Federica Ricci, Belinda Jane Wilkes, Christopher P. O'Dea, Lorenzo Lovisari, Ricci F, Lovisari L, Kraft R. P., Massaro F., Paggi A., Liuzzo E., Tremblay G., Forman W. R., Baum S., O'Dea C., Wilkes B., Ricci, F., Lovisari, L., Kraft, R. P., Massaro, F., Paggi, A., Liuzzo, E., Tremblay, G., Forman, W. R., Baum, S., O’Dea, C., and Wilkes, B.
- Subjects
galaxies: clusters: intracluster medium ,Age of the universe ,Radio galaxy ,Astrophysics::High Energy Astrophysical Phenomena ,galaxies: active ,FOS: Physical sciences ,ISM [radio continuum] ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,0103 physical sciences ,clusters: general [galaxies] ,Surface brightness ,Brightest cluster galaxy ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,Jet (fluid) ,010308 nuclear & particles physics ,Image (category theory) ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,Redshift ,Projection (relational algebra) ,radio continuum: ISM ,13. Climate action ,Space and Planetary Science ,clusters: intracluster medium [galaxies] ,galaxies: clusters: general ,X-rays: galaxies: clusters ,Astrophysics of Galaxies (astro-ph.GA) ,active [galaxies] ,galaxie [radio continuum] ,galaxies: clusters [X-rays] ,radio continuum: galaxie ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
We present a multi-wavelength analysis based on archival radio, optical and X-ray data of the complex radio source 3C 196.1, whose host is the brightest cluster galaxy of a $z=0.198$ cluster. HST data show H$\alpha$+[N II] emission aligned with the jet 8.4 GHz radio emission. An H$\alpha$+[N II] filament coincides with the brightest X-ray emission, the northern hotspot. Analysis of the X-ray and radio images reveals cavities located at galactic- and cluster- scales. The galactic-scale cavity is almost devoid of 8.4 GHz radio emission and the south-western H$\alpha$+[N II] emission is bounded (in projection) by this cavity. The outer cavity is co-spatial with the peak of 147 MHz radio emission, and hence we interpret this depression in X-ray surface brightness as being caused by a buoyantly rising bubble originating from an AGN outburst $\sim$280 Myrs ago. A \textit{Chandra} snapshot observation allowed us to constrain the physical parameters of the cluster, which has a cool core with a low central temperature $\sim$2.8 keV, low central entropy index $\sim$13 keV cm$^2$ and a short cooling time of $\sim$500 Myr, which is $, Comment: 14 pages, 4 figures, ApJ accepted
- Published
- 2018
43. Deep Chandra Observations of ESO 428-G014: II. Spectral Properties and Morphology of the Large-Scale Extended X-ray Emission
- Author
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Junfeng Wang, Guido Risaliti, Martin Elvis, Giuseppina Fabbiano, W. P. Maksym, Margarita Karovska, and Alessandro Paggi
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Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,education.field_of_study ,010308 nuclear & particles physics ,Scattering ,Molecular cloud ,Milky Way ,Astrophysics::High Energy Astrophysical Phenomena ,Continuum (design consultancy) ,Population ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Photoionization ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Galaxy ,Luminosity ,Space and Planetary Science ,0103 physical sciences ,education ,Astrophysics - High Energy Astrophysical Phenomena ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
We present a deep Chandra spectral and spatial study of the kpc-scale diffuse X-ray emission of the Compton thick (CT) AGN ESO428-G014. The entire spectrum is best fit with composite photoionization + thermal models. The diffuse emission is more extended at the lower energies (, Comment: 38 pages, 12 figure, ApJ in press
- Published
- 2018
44. 3C 17: The BCG of a Galaxy Cluster at z = 0.22
- Author
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Francesco Massaro, Juan P. Madrid, Mischa Schirmer, Carlos J. Donzelli, Alberto Rodríguez-Ardila, and Alessandro Paggi
- Subjects
010504 meteorology & atmospheric sciences ,Radio galaxy ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,GALAXIES: CLUSTERS [X-RAYS] ,purl.org/becyt/ford/1 [https] ,Intracluster medium ,0103 physical sciences ,Cluster (physics) ,Surface brightness ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,Galaxy cluster ,INDIVIDUAL (3C 17, PKS 0035'02) [GALAXIES] ,0105 earth and related environmental sciences ,Physics ,Velocity dispersion ,Astronomy and Astrophysics ,purl.org/becyt/ford/1.3 [https] ,Astrophysics - Astrophysics of Galaxies ,Redshift ,Galaxy ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,CLUSTERS: GENERAL [GALAXIES] - Abstract
Gemini Multi Object Spectrograph medium-resolution spectra and photometric data of 39 objects in the field of the radio galaxy 3C 17 are presented. Based on the new data, a previously uncataloged cluster of galaxies is identified at a mean redshift of z = 0.220 ± 0.003, a projected virial radius of 0.37 Mpc, and a velocity dispersion of σ v = 821 ± 171 km s-1. The brightest member of this cluster is 3C 17, with M r = -22.45 mag. The surface brightness profile of 3C 17 is best fit with two components (Exponential + Sérsic) characteristic of brightest cluster galaxies. The spectrum of 3C 17 is dominated by broad emission lines Hα + N[ ii] and Hβ + [O iii]. Analysis of Chandra data shows extended emission around the cluster core that supports the existence of hot gas cospatial with 3C 17. The discovery of a cluster of galaxies around 3C 17 better explains the sharply bent morphology of the radio jet given that it propagates through a dense intracluster medium. Fil: Madrid, Juan P.. Commonwealth Scientific And Industrial Research Organization; Australia Fil: Donzelli, Carlos Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentina Fil: Rodríguez-Ardila, Alberto. Laboratorio Nacional de Astrofisica; Brasil. Instituto Astrofisico de Canarias; España Fil: Paggi, Alessandro. Istituto Nazionale di Astrofisica; Italia Fil: Massaro, Francesco. Istituto Nazionale di Astrofisica; Italia Fil: Schirmer, Mischa. Gemini Observatorysouthern Operations Center; Chile. Max Planck Institute For Astronomy; Alemania
- Published
- 2018
45. Deep Chandra Observations of ESO 428-G01. III. High-resolution Spectral Imaging of the Ionization Cone and Radio Jet Region
- Author
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Margarita Karovska, Junfeng Wang, Martin Elvis, Giuseppina Fabbiano, Alessandro Paggi, and W. P. Maksym
- Subjects
Physics ,Jet (fluid) ,medicine.medical_specialty ,010308 nuclear & particles physics ,High resolution ,Astronomy and Astrophysics ,Astrophysics ,01 natural sciences ,Spectral imaging ,Cone (topology) ,Space and Planetary Science ,Ionization ,0103 physical sciences ,medicine ,010303 astronomy & astrophysics - Published
- 2018
46. The 3CR Chandra Snapshot Survey: Extragalactic Radio Sources with 0.5 < z < 1.0
- Author
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Joanna Kuraszkiewicz, Francesco Massaro, William R. Forman, V. Missaglia, Alessandro Paggi, Stefi A. Baum, Daniel E. Harris, Ralph Kraft, Elisabetta Liuzzo, Grant R. Tremblay, C. P. O'Dea, C. Stuardi, and Belinda Jane Wilkes
- Subjects
Physics ,QSOS ,radio continuum: galaxies ,High energy ,010308 nuclear & particles physics ,Radio galaxy ,Astrophysics::High Energy Astrophysical Phenomena ,galaxies: active ,Astronomy and Astrophysics ,Quasar ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Radiation ,X-rays: general ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Redshift ,Space and Planetary Science ,0103 physical sciences ,Snapshot (computer storage) ,Spectral analysis ,Astrophysics - High Energy Astrophysical Phenomena ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
This paper presents the analysis of Chandra X-ray snapshot observations of a subsample of the extragalactic sources listed in the revised Third Cambridge radio catalog (3CR), previously lacking X-ray observations and thus observed during Chandra Cycle 15. This data set extends the current Chandra coverage of the 3CR extragalactic catalog up to redshift $z$=1.0. Our sample includes 22 sources consisting of one compact steep spectrum (CSS) source, three quasars (QSOs), and 18 FR\,II radio galaxies. As in our previous analyses, here we report the X-ray detections of radio cores and extended structures (i.e., knots, hotspots and lobes) for all sources in the selected sample. We measured their X-ray intensities in three energy ranges: soft (0.5--1 keV), medium (1--2 keV) and hard (2-7 keV) and we also performed standard X-ray spectral analysis for brighter nuclei. All radio nuclei in our sample have an X-ray counterpart. We also discovered X-ray emission associated with the eastern knot of 3CR\,154, with radio hotspots in 3CR\,41, 3CR\,54 and 3CR\,225B and with the southern lobe of 3CR\,107. Extended X-ray radiation around the nuclei 3CR\,293.1 and 3CR\,323 on a scale of few tens kpc was also found. X-ray extended emission, potentially arising from the hot gas in the intergalactic medium and/or due to the high energy counterpart of lobes, is detected for 3CR\,93, 3CR\,154, 3CR\,292 and 3CR\, 323 over a few hundreds kpc-scale. Finally, this work also presents an update on the state-of-the-art of Chandra and XMM-Newton observations for the entire 3CR sample., Comment: 25 pages, 6 tables, 27 figures, ApJS accepted for publication (pre-proof version)
- Published
- 2018
47. CHEERS Results from NGC 3393, III: Chandra X-ray Spectroscopy of the Narrow Line Region
- Author
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W. Peter Maksym, John C. Raymond, Junfeng Wang, Guido Risaliti, Thaisa Storchi-Bergmann, Margarita Karovska, Giuseppina Fabbiano, Martin Elvis, and Alessandro Paggi
- Subjects
Physics ,High Energy Astrophysical Phenomena (astro-ph.HE) ,X-ray spectroscopy ,010504 meteorology & atmospheric sciences ,Astrophysics::High Energy Astrophysical Phenomena ,FOS: Physical sciences ,Astronomy and Astrophysics ,Torus ,Photoionization ,Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Galaxy ,Imaging spectroscopy ,Space and Planetary Science ,Excited state ,0103 physical sciences ,Astrophysics::Solar and Stellar Astrophysics ,Outflow ,Astrophysics - High Energy Astrophysical Phenomena ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,0105 earth and related environmental sciences ,Line (formation) - Abstract
We present spatially resolved Chandra narrow-band imaging and imaging spectroscopy of NGC 3393. This galaxy hosts a Compton-thick Seyfert 2 AGN with sub-kpc bipolar outflows that are strongly interacting with the circumnuclear gas. We identify narrow-band excess emission associated with the Ne IX 0.905 keV transition (with likely contributions due to intermediate-state iron emission) that points to strong shocks driven by AGN feedback. Imaging spectroscopy resolves outflow-ISM interaction sites and the surrounding ISM at ~100 pc scales, and suggests the presence of a hot AGN wind above the plane at radii beyond the shock sites. The cross-cone shows evidence for reprocessing of photoionization which has passed through gaps in the torus, and also for collisionally excited plasma which may be powered by a shock-confined equatorial outflow. Deep X-ray observations at sub-arcsecond resolution (such as may be performed very efficiently by Lynx, which would also energetically resolve the complex line emission) are necessary to eliminate model degeneracies and reduce uncertainties in local feedback properties., Comment: 26 pages, 11 figures, 33 images, 6 tables. Part 3 of a series (Part 1 was: 2016, ApJ, 829, 46; Part 2 was: 2017, ApJ, 844, 69). Submitted to ApJ
- Published
- 2018
- Full Text
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48. The 3CR Chandra Snapshot Survey: Extragalactic Radio Sources with Redshifts between 1 and 1.5
- Author
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Joanna Kuraszkiewicz, V. Missaglia, Belinda Jane Wilkes, Francesco Massaro, William R. Forman, Ralph Kraft, C. Stuardi, Stefi A. Baum, Elisabetta Liuzzo, Grant R. Tremblay, Alessandro Paggi, Christopher P. O'Dea, Federica Ricci, D. E. Harris, Stuardi, C., Missaglia, V., Massaro, F., Ricci, F., Liuzzo, E., Paggi, A., Kraft, R. P., Tremblay, G. R., Baum, S. A., O’Dea, C. P., Wilkes, B. J., Kuraszkiewicz, J., Forman, W. R., and Harris, D. E.
- Subjects
radio continuum: galaxies ,Physics ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,galaxies: active ,Astronomy ,Astronomy and Astrophysics ,Astrophysics::Cosmology and Extragalactic Astrophysics ,X-rays: general ,01 natural sciences ,Redshift ,Space and Planetary Science ,general [X-rays] ,0103 physical sciences ,active [galaxies] ,Snapshot (computer storage) ,galaxies: active – radio continuum: galaxies – X-rays: general ,galaxie [radio continuum] ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
The aim of this paper is to present an analysis of newly acquired X-ray observations of 16 extragalactic radio sources listed in the Third Cambridge Revised (3CR) catalog and not previously observed by Chandra. Observations were performed during Chandra Cycle 17, extending X-ray coverage for the 3CR extragalactic catalog up to z = 1.5. Among the 16 targets, two lie at z < 0.5 (3CR 27 at z = 0.184 and 3CR 69 at z = 0.458); all of the remaining 14 have redshifts between 1.0 and 1.5. In the current sample, there are three compact steep spectrum (CSS) sources, three quasars, and an FR I radio galaxy, while the other nine are FR II radio galaxies. All radio sources have an X-ray counterpart. We measured nuclear X-ray fluxes as well as X-ray emission associated with radio jet knots, hotspots, or lobes in three energy bands: soft (0.5-1. keV), medium (1-2. keV), and hard (2-7 keV). We also performed standard X-ray spectral analysis for the four brightest nuclei. We discovered X-ray emission associated with the radio lobe of 3CR 124, a hotspot of the quasar 3CR 220.2, another hotspot of the radio galaxy 3CR 238, and the jet knot of 3CR 297. We also detected extended X-ray emission around the nuclear region of 3CR 124 and 3CR 297 on scales of several tens of kiloparsecs. Finally, we present an update on the X-ray observations performed with Chandra and XMM-Newton on the entire 3CR extragalactic catalog.
- Published
- 2018
49. Chandra and NuSTAR follow-up observations of Swift-BAT selected AGN
- Author
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Marco Ajello, L. Marcotulli, Stefano Marchesi, A. Segreto, Giancarlo Cusumano, V. La Parola, Luke Tremblay, and Alessandro Paggi
- Subjects
Swift ,Active galactic nucleus ,Photon ,010504 meteorology & atmospheric sciences ,Astrophysics::High Energy Astrophysical Phenomena ,galaxies: active ,FOS: Physical sciences ,Astrophysics ,Total population ,Astrophysics::Cosmology and Extragalactic Astrophysics ,01 natural sciences ,Spectral line ,0103 physical sciences ,Spectral fitting ,Absorption (electromagnetic radiation) ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,computer.programming_language ,Physics ,COSMIC cancer database ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,X-rays: galaxies ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,galaxies: nuclei ,computer - Abstract
Based on current models of the Cosmic X-ray Background (CXB), heavily obscured Active Galactic Nuclei (AGN) are expected to make up ~10% of the peak emission of the CXB and ~20% of the total population of AGN, yet few of these sources have been recorded and characterized in current surveys. Here we present the Chandra follow-up observation of 14 AGN detected by Swift-BAT. For five sources in the sample, NuSTAR observations in the 3-80 keV band are also available. The X-ray spectral fitting over the 0.3-150 keV energy range allows us to determine the main X-ray spectral parameters, such as the photon index and the intrinsic absorption, of these objects, and to make hypotheses on the physical structures responsible for the observed spectra. We find that 13 of the 14 objects are absorbed AGN, and one is a candidate Compton thick AGN, having intrinsic absorption NH>1E24 cm^{-2}. Finally, we verified that the use of NuSTAR observations is strategic to strongly constrain the properties of obscured AGN, since the best-fit values we obtained for parameters such as the power-law photon index and the intrinsic absorption NH changed sometimes significantly fitting the spectra with and without the use of NuSTAR data., 13 pages, 4 figures, 4 tables. Accepted for publication on ApJ
- Published
- 2017
- Full Text
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50. X-Ray Emission from the Nuclear Region of Arp 220
- Author
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W. Peter Maksym, Junfeng Wang, Margarita Karovska, Guido Risaliti, Martin Elvis, Giuseppina Fabbiano, Alessandro Paggi, Jay Gallagher, and Jonathan C. McDowell
- Subjects
Physics ,galaxies: individual (Arp 220) ,010308 nuclear & particles physics ,Infrared ,galaxies: active ,X-ray ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Kinetic energy ,01 natural sciences ,Astrophysics - Astrophysics of Galaxies ,Interstellar medium ,X-rays: galaxies ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Content (measure theory) ,galaxies: interactions ,Spectral analysis ,010303 astronomy & astrophysics ,Equivalent width ,Line (formation) - Abstract
We present an imaging and spectral analysis of the nuclear region of the ULIRG merger Arp 220, using deep \textit{Chandra}-ACIS observations summing up to \(\sim 300\mbox{ ks}\). Narrow-band imaging with sub-pixel resolution of the innermost nuclear region reveals two distinct Fe-K emitting sources, coincident with the infrared and radio nuclear clusters. These sources are separated by 1' (\(\sim 380\) pc). The X-ray emission is extended and elongated in the eastern nucleus, like the disk emission observed in millimeter radio images, suggesting starburst dominance in this region. We estimate Fe-K equivalent width \(\gtrsim 1\) keV for both sources, and observed 2-10 keV luminosities \(\sim 2\times{10}^{40}\mbox{ erg}\mbox{ s}^{-1}\) (W) and \(\sim 3 \times {10}^{40}\mbox{ erg}\mbox{ s}^{-1}\) (E). In the 6-7 keV band the emission from these regions is dominated by the 6.7 keV Fe \textsc{xxv} line, suggesting contribution from collisionally ionized gas. The thermal energy content of this gas is consistent with kinetic energy injection in the interstellar medium by Type II SNe. However, nuclear winds from hidden AGN (\(\varv\sim 2000 \mbox{ km}\mbox{ s}^{-1}\)) cannot be excluded. The \(3��\) upper limits on the neutral Fe-K\(��\) flux of the nuclear regions correspond to intrinsic AGN 2-10 keV luminosities \(< 1\times {10}^{42}\mbox{ erg}\mbox{ s}^{-1}\) (W) and \(< 0.4\times {10}^{42}\mbox{ erg}\mbox{ s}^{-1}\) (E). For typical AGN SEDs the bolometric luminosities are \(< 3\times {10}^{43}\mbox{ erg}\mbox{ s}^{-1}\) (W) and \(< 8\times {10}^{43}\mbox{ erg}\mbox{ s}^{-1}\) (E), and black hole masses \(, 13 pages, 9 figures, accepted for publication on ApJ. arXiv admin note: text overlap with arXiv:1303.2630
- Published
- 2017
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