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983 results on '"A. Lahteenmaki"'

1. Urban wireless traffic evolution: the role of new devices and the effect of policy

Author: Benseny, Jaume, Lahteenmaki, Jarno, Toyli, Juuso, and Hammainen, Heikki
Subjects: Computer Science - Networking and Internet Architecture, Economics - General Economics
Abstract: The emergence of new wireless technologies, such as the Internet of Things, allows digitalizing new and diverse urban activities. Thus, wireless traffic grows in volume and complexity, making prediction, investment planning, and regulation increasingly difficult. This article characterizes urban wireless traffic evolution, supporting operators to drive mobile network evolution and policymakers to increase national and local competitiveness. We propose a holistic method that widens previous research scope, including new devices and the effect of policy from multiple government levels. We provide an analytical formulation that combines existing complementary methods on traffic evolution research and diverse data sources. Results for a centric area of Helsinki during 2020-2030 indicate that daily volumes increase, albeit a surprisingly large part of the traffic continues to be generated by smartphones. Machine traffic gains importance, driven by surveillance video cameras and connected cars. While camera traffic is sensitive to law enforcement policies and data regulation, car traffic is less affected by transport electrification policy. High-priority traffic remains small, even under encouraging autonomous vehicle policies. We suggest that 5G small cells might be needed around 2025, albeit the utilization of novel radio technology and additional mid-band spectrum could delay this need until 2029. We argue that mobile network operators inevitably need to cooperate in constructing a single, shared small cell network to mitigate the high deployment costs of massively deploying small cells. We also provide guidance to local and national policymakers for IoT-enabled competitive gains via the mitigation of five bottlenecks. For example, local monopolies for mmWave connectivity should be facilitated on space-limited urban furniture or risk an eventual capacity crunch, slowing down digitalization.
Published: 2023
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2. Impact of age and sex on survival outcomes in patients aged 1-45 years with acute lymphoblastic leukemia treated according to the stratification used in the NOPHO ALL2008 trial

Author: Tuomas Lahteenmaki Taalas, Trausti Oskarsson, Mats Heyman, Bendik Lund, Kristi Lepik, Goda Vaitkevičiene, Olafur Gisli Jonsson, Julia Eriksson, Nina Toft, Laimonas Griškevičius, Helene Hallbook, Katrin Palk, Ulla Wartiovaara-Kautto, Petter Quist-Paulsen, Ulrika Noren-Nystrom, Kim Vettenranta, Jonas Abrahamsson, Kjeld Schmiegelow, and Paivi M Lahteenmaki
Subjects: Diseases of the blood and blood-forming organs, RC633-647.5
Abstract: Age and sex have historically been associated with differences in acute lymphoblastic leukemia (ALL) survival. In the NOPHO ALL2008 trial, patients aged 1-45 years with BCR::ABL1-negative B-precursor and Tcell ALL were included, but neither sex nor age was integrated into risk group allocation. Among 1,771 trial patients stratified into protocol-appropriate risk groups, we estimated the impact of age and sex on survival (even after relapse) and toxicities prospectively registered at three-month intervals. In multivariate Cox regression analysis adjusted by sex, age group, and risk group, age but not sex was an independent risk factor for reduced 5-year event-free survival (EFS), hazard ratio 1.57 (95%CI 1.15-2.14) for patients 10-17.9 years, and 2.70 (2.03-3.58) for patients 18-45 years, compared to patients
Published: 2025
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3. Multi-wavelength temporal variability of the blazar PKS 1510-089

Author: Yuan, Q., Kushwaha, Pankaj, Gupta, Alok C., Tripathi, Ashutosh, Wiita, Paul J., Zhang, M., Liu, X., Lahteenmaki, Anne, Tornikoski, Merja, Tammi, Joni, Ramakrishnan, Venkatessh, Cui, L., Wang, X., Gu, M. F., Bambi, Cosimo, and Volvach, A. E.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We perform correlation and periodicity search analyses on long-term multi-band light curves of the FSRQ 1510-089 observed by the space-based Fermi--Large Area Telescope in gamma-rays, the SMARTS and Steward Observatory telescopes in optical and near-infrared (NIR) and the 13.7 m radio telescope in Metsahovi Radio Observatory between 2008 and 2018. The z-transform discrete correlation function method is applied to study the correlation and possible time lags among these multi band light curves. Among all pairs of wavelengths, the gamma-ray vs. optical/NIR and optical vs. NIR correlations show zero time lags; however, both the gamma-ray and optical/NIR emissions precede the radio radiation. The Generalized Lomb-Scargle periodogram, Weighted Wavelet Z-transform, and REDFIT techniques are employed to investigate the unresolved-core-emission dominated 37 GHz light curve and yield evidence for a quasi-period around 1540 days, although given the length of the whole data set it cannot be claimed to be significant. We also investigate the optical/NIR color variability and find that this source shows a simple redder-when-brighter behavior over time, even in the low flux state., Comment: Accepted for publication in ApJ; 20 pages, 9 figures, 4 tables
Published: 2023
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4. VERITAS discovery of very high energy gamma-ray emission from S3 1227+25 and multiwavelength observations

Author: Acharyya, Atreya, Adams, Colin, Archer, Avery, Bangale, Priyadarshini, Benbow, Wystan, Brill, Aryeh, Christiansen, Jodi, Chromey, Alisha, Errando, Manel, Falcone, Abe, Feng, Qi, Finley, John, Foote, Gregory, Fortson, Lucy, Furniss, Amy, Gallagher, Greg, Hanlon, William, Hanna, David, Hervet, Olivier, Hinrichs, Claire, Hoang, John, Holder, Jamie, Jin, Weidong, Johnson, Madalyn, Kaaret, Philip, Kertzman, Mary P., Kieda, David, Kleiner, Tobias, Korzoun, Nikolas, Krennrich, Frank, Lang, Mark, Lundy, Matthew, Maier, Gernot, McGrath, Conor, Millard, Matthew, Millis, John, Mooney, Connor, Moriarty, Patrick, Mukherjee, Reshmi, O'Brien, Stephan, Ong, Rene A., Pohl, Martin, Pueschel, Elisa, Quinn, John, Ragan, Kenneth J., Reynolds, Paul, Ribeiro, Deivid, Roache, Emmet Thomas, Sadeh, Iftach, Sadun, Alberto, Saha, Lab, Santander, Marcos, Sembroski, Glenn, Shang, Ruo, Splettstoesser, Megan, Talluri, Anjana, Tucci, James, Vassiliev, Vladimir, Williams, David, Wong, Sam, Hovatta, Talvikki, Jorstad, Svetlana, Kiehlmann, Sebastian, Lahteenmaki, Anne, Liodakis, Ioannis, Marscher, Alan, Max-Moerbeck, Walter, Readhead, Anthony, Reeves, Rodrigo, Smith, Paul S, and Tornikoski, Merja
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report the detection of very high energy gamma-ray emission from the blazar S3 1227+25 (VER J1230+253) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS). VERITAS observations of the source were triggered by the detection of a hard-spectrum GeV flare on May 15, 2015 with the Fermi-Large Area Telescope (LAT). A combined five-hour VERITAS exposure on May 16th and May 18th resulted in a strong 13$\sigma$ detection with a differential photon spectral index, $\Gamma$ = 3.8 $\pm$ 0.4, and a flux level at 9% of the Crab Nebula above 120 GeV. This also triggered target of opportunity observations with Swift, optical photometry, polarimetry and radio measurements, also presented in this work, in addition to the VERITAS and Fermi-LAT data. A temporal analysis of the gamma-ray flux during this period finds evidence of a shortest variability timescale of $\tau_{obs}$ = 6.2 $\pm$ 0.9 hours, indicating emission from compact regions within the jet, and the combined gamma-ray spectrum shows no strong evidence of a spectral cut-off. An investigation into correlations between the multiwavelength observations found evidence of optical and gamma-ray correlations, suggesting a single-zone model of emission. Finally, the multiwavelength spectral energy distribution is well described by a simple one-zone leptonic synchrotron self-Compton radiation model., Comment: 18 pages, 6 figures. Accepted for publication in the Astrophysical Journal (ApJ)
Published: 2023
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5. Interactions between the jet and disk wind in a nearby radio intermediate quasar III Zw 2

Author: Wang, Ailing, An, Tao, Guo, Shaoguang, Mohan, Prashanth, Chamani, Wara, Baan, Willem A., Hovatta, Talvikki, Falcke, Heino, Galvin, Tim J., Hurley-Walker, Natasha, Jaiswal, Sumit, Lahteenmaki, Anne, Lao, Baoqiang, Lv, Weijia, Tornikoski, Merja, and Zhang, Yingkang
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies
Abstract: Disk winds and jets are ubiquitous in active galactic nuclei (AGN), and how these two components interact remains an open question. We study the radio properties of a radio-intermediate quasar III Zw 2. We detect two jet knots J1 and J2 on parsec scales, which move at a mildly apparent superluminal speed of $1.35\,c$. Two $\gamma$-ray flares were detected in III Zw 2 in 2009--2010, corresponding to the primary radio flare in late 2009 and the secondary radio flare in early 2010. The primary 2009 flare was found to be associated with the ejection of J2. The secondary 2010 flare occurred at a distance of $\sim$0.3 parsec from the central engine, probably resulting from the collision of the jet with the accretion disk wind. The variability characteristics of III Zw 2 (periodic radio flares, unstable periodicity, multiple quasi-periodic signals and possible harmonic relations between them) can be explained by the global instabilities of the accretion disk. These instabilities originating from the outer part of the warped disk propagate inwards and can lead to modulation of the accretion rate and consequent jet ejection. At the same time, the wobbling of the outer disk may also lead to oscillations of the boundary between the disk wind and the jet tunnel, resulting in changes in the jet-wind collision site. III Zw 2 is one of the few cases observed with jet-wind interactions, and the study in this paper is of general interest for gaining insight into the dynamic processes in the nuclear regions of AGN., Comment: accepted by ApJ
Published: 2022
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6. Multiwavelength variability power spectrum analysis of the blazars 3C 279 and PKS 1510-089 on multiple timescales

Author: Goyal, Arti, Soida, Marian, Stawarz, Lukasz, Wiita, Paul J., Nilsson, Kari, Jorstad, Svetlana, Marscher, Alan P., Aller, Margo F., Aller, Hugh D., Lahteenmaki, Anne, Hovatta, Talvikki, Zola, Staszek, Nalewajko, Krzysztof, Tornikoski, Merja, Tammi, Joni, Hodges, Mark, Kiehlmann, Sebastian, Readhead, Anthony C. S., Max-Moerbeck, Walter, Lindfors, Elina, Ramazani, Vandad Fallah, Reichart, D. E., Caton, D. B., Valverde, Janeth, Horan, Deirdre, Ojha, Roopesh, and van Zyl, Pfesesani
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the results of variability power spectral density (PSD) analysis using multiwavelength radio to GeV\,$\gamma$-ray light curves covering decades/years to days/minutes timescales for the blazars 3C 279 and PKS 1510-089. The PSDs are modeled as single power-laws, and the best-fit spectral shape is derived using the `power spectral response' method. With more than ten years of data obtained with weekly/daily sampling intervals, most of the PSDs cover ~2-4 decades in temporal frequency; moreover, in the optical band, the PSDs cover ~6 decades for 3C 279 due to the availability of intranight light curves. Our main results are the following: (1) on timescales ranging from decades to days, the synchrotron and the inverse Compton spectral components, in general, exhibit red-noise (slope ~2) and flicker-noise (slope ~1) type variability, respectively; (2) the slopes of $\gamma$-ray variability PSDs obtained using a 3-hr integration bin and a 3-weeks total duration exhibit a range between ~1.4 and ~2.0 (mean slope = 1.60$\pm$0.70), consistent within errors with the slope on longer timescales; (3) comparisons of fractional variability indicate more power on timescales $\leq$100\, days at $\gamma$-ray frequencies as compared to longer wavelengths, in general (except between $\gamma$-ray and optical frequencies for PKS 1510$-$089); (4) the normalization of intranight optical PSDs for 3C\,279 appears to be a simple extrapolation from longer timescales, indicating a continuous (single) process driving the variability at optical wavelengths; (5) the emission at optical/infrared wavelengths may involve a combination of disk and jet processes for PKS\,1510$-$089., Comment: ApJ accepted. Comments are welcome
Published: 2021
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7. Probing the innermost regions of AGN jets and their magnetic fields with RadioAstron. V. Space and ground millimeter-VLBI imaging of OJ 287

Author: Gómez, Jose L., Traianou, Efthalia, Krichbaum, Thomas P., Lobanov, Andrei, Fuentes, Antonio, Lico, Rocco, Zhao, Guang-Yao, Bruni, Gabriele, Kovalev, Yuri Y., Lahteenmaki, Anne, Voitsik, Petr A., Lisakov, Mikhail M., Angelakis, Emmanouil, Bach, Uwe, Casadio, Carolina, Cho, Ilje, Dey, Lankeswar, Gopakumar, Achamveedu, Gurvits, Leonid, Jorstad, Svetlana G., Kovalev, Yuri A., Lister, Matthew L., Marscher, Alan P., Myserlis, Ioannis, Pushkarev, Alexander, Ros, Eduardo, Savolainen, Tuomas, Tornikoski, Merja, Valtonen, Mauri J., and Zensus, Anton
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the first polarimetric space VLBI observations of OJ 287, observed with RadioAstron at 22 GHz during a perigee session on 2014 April 4 and five near-in-time snapshots, together with contemporaneous ground VLBI observations at 15, 43, and 86 GHz. Ground-space fringes were obtained up to a projected baseline of 3.9 Earth diameters during the perigee session, and at a record 15.1 Earth diameters during the snapshot sessions, allowing us to image the innermost jet at an angular resolution of $\sim50\mu$as, the highest ever achieved at 22 GHz for OJ 287. Comparison with ground-based VLBI observations reveals a progressive jet bending with increasing angular resolution that agrees with predictions from a supermassive binary black hole model, although other models cannot be ruled out. Spectral analyses suggest that the VLBI core is dominated by the internal energy of the emitting particles during the onset of a multi-wavelength flare, while the parsec-scale jet is consistent with being in equipartition between the particles and magnetic field. Estimated minimum brightness temperatures from the visibility amplitudes show a continued rising trend with projected baseline length up to $10^{13}$ K, reconciled with the inverse Compton limit through Doppler boosting for a jet closely oriented to the line of sight. The observed electric vector position angle suggests that the innermost jet has a predominantly toroidal magnetic field, which together with marginal evidence of a gradient in rotation measure across the jet width indicate that the VLBI core is threaded by a helical magnetic field, in agreement with jet formation models.
Published: 2021
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8. Human nature vs. Food system transitions?

Author: Lahteenmaki-Uutela, Anu
Published: 2021

9. Association of IceCube neutrinos with radio sources observed at Owens Valley and Mets\'ahovi Radio Observatories

Author: Hovatta, T., Lindfors, E., Kiehlmann, S., Max-Moerbeck, W., Hodges, M., Liodakis, I., Lahteenmaki, A., Pearson, T. J., Readhead, A. C. S., Reeves, R. A., Suutarinen, S., Tammi, J., and Tornikoski, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Identifying the most likely sources for high-energy neutrino emission has been one of the main topics in high-energy astrophysics ever since the first observation of high-energy neutrinos by the IceCube Neutrino Observatory. Active galactic nuclei with relativistic jets, also known as blazars, have been considered to be one of the main candidates because of their ability to accelerate particles to high energies. We study the connection between radio emission and IceCube neutrino events using data from the Owens Valley Radio Observatory (OVRO) and Mets\"ahovi Radio Observatory blazar monitoring programs. We identify sources in our radio monitoring sample that are positionally consistent with IceCube high-energy neutrino events. We estimate their mean flux density and variability amplitudes around the neutrino arrival time, and compare these with values from random samples to establish the significance of our results. We find radio source associations within our samples with 15 high-energy neutrino events detected by IceCube. Nearly half of the associated sources are not detected in the $\gamma$-ray energies, but their radio variability properties and Doppler boosting factors are similar to the $\gamma$-ray detected objects in our sample, meaning that they could still be potential neutrino emitters. We find that the number of strongly flaring objects in our statistically complete OVRO samples is unlikely to be a random coincidence (at $2\sigma$ level). Based on our results, we conclude that although it is clear that not all neutrino events are associated with strong radio flaring blazars, observations of large-amplitude radio flares in a blazar at the same time as a neutrino event are unlikely to be a random coincidence., Comment: Accepted for publication in A&A (18 pages, 6 figures). Accepted version (v2) includes changes to methodology and associations, but the main conclusions are unaffected. V3 minor fix to numbers in Sect. 3.3.1. and some language edits
Published: 2020
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10. Unravelling the complex behavior of Mrk 421 with simultaneous X-ray and VHE observations during an extreme flaring activity in April 2013

Author: MAGIC collaboration, Acciari, V. A., Ansoldi, S., Antonelli, L. A., Engels, A. Arbet, Baack, D., Babic, A., Banerjee, B., de Almeida, U. Barres, Barrio, J. A., Gonzalez, J. Becerra, Bednarek, W., Bellizzi, L., Bernardini, E., Berti, A., Besenrieder, J., Bhattacharyya, W., Bigongiari, C., Biland, A., Blanch, O., Bonnoli, G., Bosnjak, Z., Busetto, G., Carosi, R., Ceribella, G., Cerruti, M., Chai, Y., Chilingarian, A., Cikota, S., Colak, S. M., Colin, U., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., D'Elia, V., Da Vela, P., Dazzi, F., De Angelis, A., De Lotto, B., Del Puppo, F., Delfino, M., Delgado, J., Depaoli, D., Di Pierro, F., Di Venere, L., Espineira, E. Do Souto, Prester, D. Dominis, Donini, A., Dorner, D., Doro, M., Elsaesser, D., Ramazani, V. Fallah, Fattorini, A., Ferrara, G., Foffano, L., Fonseca, M. V., Font, L., Fruck, C., Fukami, S., Lopez, R. J. Garcia, Garczarczyk, M., Gasparyan, S., Gaug, M., Giglietto, N., Giordano, F., Gliwny, P., Godinovic, N., Green, D., Hadasch, D., Hahn, A., Herrera, J., Hoang, J., Hrupec, D., Hutten, M., Inada, T., Inoue, S., Ishio, K., Iwamura, Y., Jouvin, L., Kajiwara, Y., Kerszberg, D., Kobayashi, Y., Kubo, H., Kushida, J., Lamastra, A., Lelas, D., Leone, F., Lindfors, E., Lombardi, S., Longo, F., Lopez, M., Lopez-Coto, R., Lopez-Oramas, A., Loporchio, S., Fraga, B. Machado de Oliveira, Maggio, C., Majumdar, P., Makariev, M., Mallamaci, M., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Mariotti, M., Martinez, M., Mazin, D., Mender, S., Micanovic, S., Miceli, D., Miener, T., Minev, M., Miranda, J. M., Mirzoyan, R., Molina, E., Moralejo, A., Morcuende, D., Moreno, V., Moretti, E., Munar-Adrover, P., Neustroev, V., Nigro, C., Nilsson, K., Ninci, D., Nishijima, K., Noda, K., Nogues, L., Nozaki, S., Ohtani, Y., Oka, T., Otero-Santos, J., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Pavletic, L., Penil, P., Peresano, M., Persic, M., Moroni, P. G. Prada, Prandini, E., Puljak, I., Rhode, W., Ribo, M., Rico, J., Righi, C., Rugliancich, A., Saha, L., Sahakyan, N., Saito, T., Sakurai, S., Satalecka, K., Schleicher, B., Schmidt, K., Schweizer, T., Sitarek, J., Snidaric, I., Sobczynska, D., Spolon, A., Stamerra, A., Strom, D., Strzys, M., Suda, Y., Suric, T., Takahashi, M., Tavecchio, F., Temnikov, P., Terzic, T., Teshima, M., Torres-Alba, N., Tosti, L., van Scherpenberg, J., Vanzo, G., Acosta, M. Vazquez, Ventura, S., Verguilov, V., Vigorito, C. F., Vitale, V., Vovk, I., Will, M., Zaric, D., groups, Other, Petropoulou, M., Finke, J., D'Ammando, F., Balokovic, M., Madejski, G., Mori, K., Puccetti, Simonetta, Leto, C., Perri, M., Verrecchia, F., Villata, M., Raiteri, C. M., Agudo, I., Bachev, R., Berdyugin, A., Blinov, D. A., Chanishvili, R., Chen, W. P., Chigladze, R., Damljanovic, G., Eswaraiah, C., Grishina, T. S., Ibryamov, S., Jordan, B., Jorstad, S. G., Joshi, M., Kopatskaya, E. N., Kurtanidze, O. M., Kurtanidze, S. O., Larionova, E. G., Larionova, L. V., Larionov, V. M., Latev, G., Lin, H. C., Marscher, A. P., Mokrushina, A. A., Morozova, D. A., Nikolashvili, M. G., Semkov, E., Smith, P. S., Strigachev, A., Troitskaya, Yu. V., Troitsky, I. S., Vince, O., Barnes, J., Guever, T., Moody, J. W., Sadun, A. C., Hovatta, T., Richards, J. L., Max-Moerbeck, W., Readhead, A. C. R., Lahteenmaki, A., Tornikoski, M., Tammi, J., Ramakrishnan, V., and Reinthal, R.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report on a multi-band variability and correlation study of the TeV blazar Mrk 421 during an exceptional flaring activity observed from 2013 April 11 to 2013 April 19. The study uses, among others, data from GASP-WEBT, Swift, NuSTAR, Fermi-LAT, VERITAS, and MAGIC. The large blazar activity, and the 43 hours of simultaneous NuSTAR and MAGIC/VERITAS observations, permitted variability studies on 15 minute time bins, and over three X-ray bands (3-7 keV, 7-30 keV and 30-80 keV) and three very-high-energy (>0.1 TeV, hereafter VHE) gamma-ray bands (0.2-0.4 TeV, 0.4-0.8 TeV and >0.8 TeV). We detected substantial flux variations on multi-hour and sub-hour timescales in all the X-ray and VHE gamma-ray bands. The characteristics of the sub-hour flux variations are essentially energy-independent, while the multi-hour flux variations can have a strong dependence on the energy of the X-ray and the VHE gamma rays. The three VHE bands and the three X-ray bands are positively correlated with no time-lag, but the strength and the characteristics of the correlation changes substantially over time and across energy bands. Our findings favour multi-zone scenarios for explaining the achromatic/chromatic variability of the fast/slow components of the light curves, as well as the changes in the flux-flux correlation on day-long timescales. We interpret these results within a magnetic reconnection scenario, where the multi-hour flux variations are dominated by the combined emission from various plasmoids of different sizes and velocities, while the sub-hour flux variations are dominated by the emission from a single small plasmoid moving across the magnetic reconnection layer., Comment: 46 pages, 17 figures, 9 tables, accepted for publication in ApJ Supplements
Published: 2020
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11. Investigating the multiwavelength behaviour of the flat spectrum radio quasar CTA 102 during 2013-2017

Author: D'Ammando, F., Raiteri, C. M., Villata, M., Acosta-Pulido, J. A., Agudo, I., Arkharov, A. A., Bachev, R., Baida, G. V., Benitez, E., Borman, G. A., Boschin, W., Bozhilov, V., Butuzova, M. S., Calcidese, P., Carnerero, M. I., Carosati, D., Casadio, C., Castro-Segura, N., Chen, W. -P., Damljanovic, G., Di Paola, A., Echevarria, J., Efimova, N. V., Ehgamberdiev, Sh. A., Espinosa, C., Fuentes, A., Giunta, A., Gomez, J. L., Grishina, T. S., Gurwell, M. A., Hiriart, D., Jermak, H., Jordan, B., Jorstad, S. G., Joshi, M., Kimeridze, G. N., Kopatskaya, E. N., Kuratov, K., Kurtanidze, O. M., Kurtanidze, S. O., Lahteenmaki, A., Larionov, V. M., Larionova, E. G., Larionova, L. V., Lazaro, C., Lin, C. S., Malmrose, M. P., Marscher, A. P., Matsumoto, K., McBreen, B., Michel, R., Mihov, B., Minev, M., Mirzaqulov, D. O., Molina, S. N., Moody, J. W., Morozova, D. A., Nazarov, S. V., Nikiforova, A. A., Nikolashvili, M. G., Ohlert, J. M., Okhmat, N., Ovcharov, E., Pinna, F., Polakis, T. A., Protasio, C., Pursimo, T., Redondo-Lorenzo, F. J., Rizzi, N., Rodriguez-Coira, G., Sadakane, K., Sadun, A. C., Samal, M. R., Savchenko, S. S., Semkov, E., Sigua, L., Skiff, B. A., Slavcheva-Mihova, L., Smith, P. S., Steele, I. A., Strigachev, A., Tammi, J., Thum, C., Tornikoski, M., Troitskaya, Yu. V., Troitsky, I. S., Vasilyev, A. A., Vince, O., Hovatta, T., Kiehlmann, S., Max-Moerbeck, W., Readhead, A. C. S., Reeves, R., Pearson, T. J., Mufakharov, T., Sotnikova, Yu. V., and Mingaliev, M. G.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present a multiwavelength study of the flat-spectrum radio quasar CTA 102 during 2013-2017. We use radio-to-optical data obtained by the Whole Earth Blazar Telescope, 15 GHz data from the Owens Valley Radio Observatory, 91 and 103 GHz data from the Atacama Large Millimeter Array, near-infrared data from the Rapid Eye Monitor telescope, as well as data from the Swift (optical-UV and X-rays) and Fermi ($\gamma$ rays) satellites to study flux and spectral variability and the correlation between flux changes at different wavelengths. Unprecedented $\gamma$-ray flaring activity was observed during 2016 November-2017 February, with four major outbursts. A peak flux of (2158 $\pm$ 63)$\times$10$^{-8}$ ph cm$^{-2}$ s$^{-1}$, corresponding to a luminosity of (2.2 $\pm$ 0.1)$\times$10$^{50}$ erg s$^{-1}$, was reached on 2016 December 28. These four $\gamma$-ray outbursts have corresponding events in the near-infrared, optical, and UV bands, with the peaks observed at the same time. A general agreement between X-ray and $\gamma$-ray activity is found. The $\gamma$-ray flux variations show a general, strong correlation with the optical ones with no time lag between the two bands and a comparable variability amplitude. This $\gamma$-ray/optical relationship is in agreement with the geometrical model that has successfully explained the low-energy flux and spectral behaviour, suggesting that the long-term flux variations are mainly due to changes in the Doppler factor produced by variations of the viewing angle of the emitting regions. The difference in behaviour between radio and higher energy emission would be ascribed to different viewing angles of the jet regions producing their emission., Comment: 24 pages, 18 figures, and 4 tables. Accepted for publication in Monthly Notices of the Royal Astronomical Society
Published: 2019
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12. CMB-S4 Decadal Survey APC White Paper

Author: Abazajian, Kevork, Addison, Graeme, Adshead, Peter, Ahmed, Zeeshan, Allen, Steven W., Alonso, David, Alvarez, Marcelo, Amin, Mustafa A., Anderson, Adam, Arnold, Kam S., Baccigalupi, Carlo, Bailey, Kathy, Barkats, Denis, Barron, Darcy, Barry, Peter S., Bartlett, James G., Thakur, Ritoban Basu, Battaglia, Nicholas, Baxter, Eric, Bean, Rachel, Bebek, Chris, Bender, Amy N., Benson, Bradford A., Berger, Edo, Bhimani, Sanah, Bischoff, Colin A., Bleem, Lindsey, Bock, James J., Bocquet, Sebastian, Boddy, Kimberly, Bonato, Matteo, Bond, J. Richard, Borrill, Julian, Bouchet, François R., Brown, Michael L., Bryan, Sean, Burkhart, Blakesley, Buza, Victor, Byrum, Karen, Calabrese, Erminia, Calafut, Victoria, Caldwell, Robert, Carlstrom, John E., Carron, Julien, Cecil, Thomas, Challinor, Anthony, Chang, Clarence L., Chinone, Yuji, Cho, Hsiao-Mei Sherry, Cooray, Asantha, Crawford, Thomas M., Crites, Abigail, Cukierman, Ari, Cyr-Racine, Francis-Yan, de Haan, Tijmen, de Zotti, Gianfranco, Delabrouille, Jacques, Demarteau, Marcel, Devlin, Mark, Di Valentino, Eleonora, Dobbs, Matt, Duff, Shannon, Duivenvoorden, Adriaan, Dvorkin, Cora, Edwards, William, Eimer, Joseph, Errard, Josquin, Essinger-Hileman, Thomas, Fabbian, Giulio, Feng, Chang, Ferraro, Simone, Filippini, Jeffrey P., Flauger, Raphael, Flaugher, Brenna, Fraisse, Aurelien A., Frolov, Andrei, Galitzki, Nicholas, Galli, Silvia, Ganga, Ken, Gerbino, Martina, Gilchriese, Murdock, Gluscevic, Vera, Green, Daniel, Grin, Daniel, Grohs, Evan, Gualtieri, Riccardo, Guarino, Victor, Gudmundsson, Jon E., Habib, Salman, Haller, Gunther, Halpern, Mark, Halverson, Nils W., Hanany, Shaul, Harrington, Kathleen, Hasegawa, Masaya, Hasselfield, Matthew, Hazumi, Masashi, Heitmann, Katrin, Henderson, Shawn, Henning, Jason W., Hill, J. Colin, Hlozek, Renée, Holder, Gil, Holzapfel, William, Hubmayr, Johannes, Huffenberger, Kevin M., Huffer, Michael, Hui, Howard, Irwin, Kent, Johnson, Bradley R., Johnstone, Doug, Jones, William C., Karkare, Kirit, Katayama, Nobuhiko, Kerby, James, Kernovsky, Sarah, Keskitalo, Reijo, Kisner, Theodore, Knox, Lloyd, Kosowsky, Arthur, Kovac, John, Kovetz, Ely D., Kuhlmann, Steve, Kuo, Chao-lin, Kurita, Nadine, Kusaka, Akito, Lahteenmaki, Anne, Lawrence, Charles R., Lee, Adrian T., Lewis, Antony, Li, Dale, Linder, Eric, Loverde, Marilena, Lowitz, Amy, Madhavacheril, Mathew S., Mantz, Adam, Matsuda, Frederick, Mauskopf, Philip, McMahon, Jeff, Meerburg, P. Daniel, Melin, Jean-Baptiste, Meyers, Joel, Millea, Marius, Mohr, Joseph, Moncelsi, Lorenzo, Mroczkowski, Tony, Mukherjee, Suvodip, Münchmeyer, Moritz, Nagai, Daisuke, Nagy, Johanna, Namikawa, Toshiya, Nati, Federico, Natoli, Tyler, Negrello, Mattia, Newburgh, Laura, Niemack, Michael D., Nishino, Haruki, Nordby, Martin, Novosad, Valentine, O'Connor, Paul, Obied, Georges, Padin, Stephen, Pandey, Shivam, Partridge, Bruce, Pierpaoli, Elena, Pogosian, Levon, Pryke, Clement, Puglisi, Giuseppe, Racine, Benjamin, Raghunathan, Srinivasan, Rahlin, Alexandra, Rajagopalan, Srini, Raveri, Marco, Reichanadter, Mark, Reichardt, Christian L., Remazeilles, Mathieu, Rocha, Graca, Roe, Natalie A., Roy, Anirban, Ruhl, John, Salatino, Maria, Saliwanchik, Benjamin, Schaan, Emmanuel, Schillaci, Alessandro, Schmittfull, Marcel M., Scott, Douglas, Sehgal, Neelima, Shandera, Sarah, Sheehy, Christopher, Sherwin, Blake D., Shirokoff, Erik, Simon, Sara M., Slosar, Anze, Somerville, Rachel, Staggs, Suzanne T., Stark, Antony, Stompor, Radek, Story, Kyle T., Stoughton, Chris, Suzuki, Aritoki, Tajima, Osamu, Teply, Grant P., Thompson, Keith, Timbie, Peter, Tomasi, Maurizio, Treu, Jesse I., Tristram, Matthieu, Tucker, Gregory, Umiltà, Caterina, van Engelen, Alexander, Vieira, Joaquin D., Vieregg, Abigail G., Vogelsberger, Mark, Wang, Gensheng, Watson, Scott, White, Martin, Whitehorn, Nathan, Wollack, Edward J., Wu, W. L. Kimmy, Xu, Zhilei, Yasini, Siavash, Yeck, James, Yoon, Ki Won, Young, Edward, and Zonca, Andrea
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Astrophysics of Galaxies
Abstract: We provide an overview of the science case, instrument configuration and project plan for the next-generation ground-based cosmic microwave background experiment CMB-S4, for consideration by the 2020 Decadal Survey., Comment: Project White Paper submitted to the 2020 Decadal Survey, 10 pages plus references. arXiv admin note: substantial text overlap with arXiv:1907.04473
Published: 2019

13. CMB-S4 Science Case, Reference Design, and Project Plan

Author: Abazajian, Kevork, Addison, Graeme, Adshead, Peter, Ahmed, Zeeshan, Allen, Steven W., Alonso, David, Alvarez, Marcelo, Anderson, Adam, Arnold, Kam S., Baccigalupi, Carlo, Bailey, Kathy, Barkats, Denis, Barron, Darcy, Barry, Peter S., Bartlett, James G., Thakur, Ritoban Basu, Battaglia, Nicholas, Baxter, Eric, Bean, Rachel, Bebek, Chris, Bender, Amy N., Benson, Bradford A., Berger, Edo, Bhimani, Sanah, Bischoff, Colin A., Bleem, Lindsey, Bocquet, Sebastian, Boddy, Kimberly, Bonato, Matteo, Bond, J. Richard, Borrill, Julian, Bouchet, François R., Brown, Michael L., Bryan, Sean, Burkhart, Blakesley, Buza, Victor, Byrum, Karen, Calabrese, Erminia, Calafut, Victoria, Caldwell, Robert, Carlstrom, John E., Carron, Julien, Cecil, Thomas, Challinor, Anthony, Chang, Clarence L., Chinone, Yuji, Cho, Hsiao-Mei Sherry, Cooray, Asantha, Crawford, Thomas M., Crites, Abigail, Cukierman, Ari, Cyr-Racine, Francis-Yan, de Haan, Tijmen, de Zotti, Gianfranco, Delabrouille, Jacques, Demarteau, Marcel, Devlin, Mark, Di Valentino, Eleonora, Dobbs, Matt, Duff, Shannon, Duivenvoorden, Adriaan, Dvorkin, Cora, Edwards, William, Eimer, Joseph, Errard, Josquin, Essinger-Hileman, Thomas, Fabbian, Giulio, Feng, Chang, Ferraro, Simone, Filippini, Jeffrey P., Flauger, Raphael, Flaugher, Brenna, Fraisse, Aurelien A., Frolov, Andrei, Galitzki, Nicholas, Galli, Silvia, Ganga, Ken, Gerbino, Martina, Gilchriese, Murdock, Gluscevic, Vera, Green, Daniel, Grin, Daniel, Grohs, Evan, Gualtieri, Riccardo, Guarino, Victor, Gudmundsson, Jon E., Habib, Salman, Haller, Gunther, Halpern, Mark, Halverson, Nils W., Hanany, Shaul, Harrington, Kathleen, Hasegawa, Masaya, Hasselfield, Matthew, Hazumi, Masashi, Heitmann, Katrin, Henderson, Shawn, Henning, Jason W., Hill, J. Colin, Hlozek, Renée, Holder, Gil, Holzapfel, William, Hubmayr, Johannes, Huffenberger, Kevin M., Huffer, Michael, Hui, Howard, Irwin, Kent, Johnson, Bradley R., Johnstone, Doug, Jones, William C., Karkare, Kirit, Katayama, Nobuhiko, Kerby, James, Kernovsky, Sarah, Keskitalo, Reijo, Kisner, Theodore, Knox, Lloyd, Kosowsky, Arthur, Kovac, John, Kovetz, Ely D., Kuhlmann, Steve, Kuo, Chao-lin, Kurita, Nadine, Kusaka, Akito, Lahteenmaki, Anne, Lawrence, Charles R., Lee, Adrian T., Lewis, Antony, Li, Dale, Linder, Eric, Loverde, Marilena, Lowitz, Amy, Madhavacheril, Mathew S., Mantz, Adam, Matsuda, Frederick, Mauskopf, Philip, McMahon, Jeff, McQuinn, Matthew, Meerburg, P. Daniel, Melin, Jean-Baptiste, Meyers, Joel, Millea, Marius, Mohr, Joseph, Moncelsi, Lorenzo, Mroczkowski, Tony, Mukherjee, Suvodip, Münchmeyer, Moritz, Nagai, Daisuke, Nagy, Johanna, Namikawa, Toshiya, Nati, Federico, Natoli, Tyler, Negrello, Mattia, Newburgh, Laura, Niemack, Michael D., Nishino, Haruki, Nordby, Martin, Novosad, Valentine, O'Connor, Paul, Obied, Georges, Padin, Stephen, Pandey, Shivam, Partridge, Bruce, Pierpaoli, Elena, Pogosian, Levon, Pryke, Clement, Puglisi, Giuseppe, Racine, Benjamin, Raghunathan, Srinivasan, Rahlin, Alexandra, Rajagopalan, Srini, Raveri, Marco, Reichanadter, Mark, Reichardt, Christian L., Remazeilles, Mathieu, Rocha, Graca, Roe, Natalie A., Roy, Anirban, Ruhl, John, Salatino, Maria, Saliwanchik, Benjamin, Schaan, Emmanuel, Schillaci, Alessandro, Schmittfull, Marcel M., Scott, Douglas, Sehgal, Neelima, Shandera, Sarah, Sheehy, Christopher, Sherwin, Blake D., Shirokoff, Erik, Simon, Sara M., Slosar, Anze, Somerville, Rachel, Spergel, David, Staggs, Suzanne T., Stark, Antony, Stompor, Radek, Story, Kyle T., Stoughton, Chris, Suzuki, Aritoki, Tajima, Osamu, Teply, Grant P., Thompson, Keith, Timbie, Peter, Tomasi, Maurizio, Treu, Jesse I., Tristram, Matthieu, Tucker, Gregory, Umiltà, Caterina, van Engelen, Alexander, Vieira, Joaquin D., Vieregg, Abigail G., Vogelsberger, Mark, Wang, Gensheng, Watson, Scott, White, Martin, Whitehorn, Nathan, Wollack, Edward J., Wu, W. L. Kimmy, Xu, Zhilei, Yasini, Siavash, Yeck, James, Yoon, Ki Won, Young, Edward, and Zonca, Andrea
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Astrophysics of Galaxies, High Energy Physics - Experiment
Abstract: We present the science case, reference design, and project plan for the Stage-4 ground-based cosmic microwave background experiment CMB-S4., Comment: 287 pages, 82 figures
Published: 2019

14. Cosmological evolution of quasar radio emission in the view of multifractality

Author: Belete, A. Bewketu, Femmam, Smain, Tornikosk, Merja, Lahteenmaki, Anne, Tammi, Joni, Leao, I. C., Martins, B. L. Canto, and De Medeiros, J. R.
Subjects: Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena
Abstract: Variations in scaling behavior in the flux and emissions of distant astronomical sources with respect to their cosmic time are important l phenomena that can provide valuable information about the dynamics within the sources and their cosmological evolution with time. Different studies have been applying linear analysis to understand and model quasars' light curves. Here, we study the multifractal behavior of selected quasars' radio emissions in their observed frame (at 22 and 37 GHz bands) and and their rest frame. To this end, we apply the wavelet transform-based multifractal analysis formalism called wavelet transform modulus maxima. In addition, we verify whether the autoregressive integrated moving average (ARIMA) models fit our data or not. In our work, we observe strong multifractal behavior for all the sources. Additionally, we find that the degree of multifractality is strongly similar for each source and significantly different between sources at 22 and 37 GHz. This similarity implies that the two frequencies have the same radiation region and mechanism, whereas the difference indicates that the sources have intrinsically different dynamics. Furthermore, we show that the degree of multifractality is the same in the observed and rest frames of the quasars, i.e., multifractality is an intrinsic property of radio quasars. Finally, we show that the ARIMA models fit the 3C 345 quasar at 22 GHz and partially fit most of the time series with the exception of the 3C 273 and 3C 279 quasars at 37 GHz, for which the models are found to be inadequate., Comment: 24 pages, 14 figures, Accepted for publication in The Astrophysical Journal
Published: 2019
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15. Historical Reindeer Corrals as Portraits of Human-Nature Relationships in Northern Finland

Author: Stark, Sari, Manninen, Outi H., Ilmolahti, Oona, and Lahteenmaki, Maria
Subjects: Animal housing -- History -- Environmental aspects, Reindeer breeding -- Social aspects -- Environmental aspects, Human beings -- Influence on nature, Earth sciences, Regional focus/area studies
Abstract: Reindeer herding has been practised in northern boreal and subarctic regions of Fennoscandia for several centuries. The gathering and separation of reindeer for slaughter and calf marking are significant and cyclical activities of reindeer herding that are commonly carried out in reindeer corrals composed of circular-shaped fences of wood or stone construction leading into the corral. Using archaeological databases, we mapped historical reindeer corrals in northern Finland dating from the late 1800s to the 1960s for the entire reindeer herding area and characterized the legacies of their past use on present-day vegetation in Perapohjola. In total, 94 corrals were located. Reindeer separations created a niche for novel plant communities with increasing graminoids in relation to dwarf shrubs and formation of a dense birch grove. Corrals have also preserved old rare trees left standing inside the corral to provide shelter for reindeer. The positioning of the corrals in the landscape was usually planned in a way that utilized man-made constructions and natural barriers, such as peatlands, and the typical behaviour of the reindeer in combination with both. When the wooden constructions had collapsed and decomposed, only the different vegetation indicates their past existence. Key words: reindeer herding; northern Finland; boreal forests; reindeer corral; historical ecology L'elevage des rennes est pratique dans les regions boreales et subarctiques nordiques de la Fennoscandie depuis des siecles. Le rassemblement et la separation des rennes a des fins d'abattage et de marquage des veaux sont d'importantes activites cycliques de l'elevage des rennes. Elles s'effectuent generalement dans des enclos a rennes composes de clotures circulaires en bois ou de constructions en pierre menant aux enclos. A l'aide de bases de donnees archeologiques, nous avons dresse la carte historique des enclos a rennes du nord de la Finlande de la fin des annees 1800 jusqu'aux annees 1960 pour l'ensemble de la zone d'elevage des rennes, puis nous avons caracterise l'heritage de leur utilisation anterieure sur la vegetation actuelle de Perapohjola. Nous avons localise 94 enclos en tout. Les separations employees pour les rennes ont donne lieu a la creation d'un creneau favorable a l'etablissement de nouvelles associations vegetales contenant plus de graminiformes par rapport aux arbustes nains et a la formation de boulaies denses. Les enclos ont egalement permis de preserver d'anciens arbres rares qui sont restes a l'interieur des enclos en guise d'abri pour les rennes. En general, l'emplacement des enclos etait planifie de sorte a tirer parti des constructions artificielles et des obstacles naturels, comme les tourbieres, et du comportement typique des rennes a l'egard de ces deux caracteristiques. Une fois les constructions en bois effondrees et decomposees, seule la vegetation differente temoigne de leur existence. Mots cles : elevage des rennes; nord de la Finlande; forets boreales; enclos a rennes; ecologie historique, Traduit pour la revue Arctic par Nicole Giguere. INTRODUCTION Ecological investigations have demonstrated that past cultural activities and historical events exert lasting legacies on present-day ecosystem structures and processes (e.g., [...]
Published: 2022
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16. The extreme blazar AO 0235+164 as seen by extensive ground and space radio observations

Author: Kutkin, A. M., Pashchenko, I. N., Lisakov, M. M., Voytsik, P. A., Sokolovsky, K. V., Kovalev, Y. Y., Lobanov, A. P., Ipatov, A. V., Aller, M. F., Aller, H. D., Lahteenmaki, A., Tornikoski, M., and Gurvits, L. I.
Subjects: Astrophysics - Astrophysics of Galaxies
Abstract: Clues to the physical conditions in radio cores of blazars come from measurements of brightness temperatures as well as effects produced by intrinsic opacity. We study the properties of the ultra compact blazar AO 0235+164 with RadioAstron ground-space radio interferometer, multi-frequency VLBA, EVN and single-dish radio observations. We employ visibility modeling and image stacking for deriving structure and kinematics of the source, and use Gaussian process regression to find the relative multi-band time delays of the flares. The multi-frequency core size and time lags support prevailing synchrotron self absorption. The intrinsic brightness temperature of the core derived from ground-based VLBI is close to the equipartition regime value. In the same time, there is evidence for ultra-compact features of the size of less than 10 $\mu$as in the source, which might be responsible for the extreme apparent brightness temperatures of up to $10^{14}$ K as measured by RadioAstron. In 2007--2016 the VLBI components in the source at 43 GHz are found predominantly in two directions, suggesting a bend of the outflow from southern to northern direction. The apparent opening angle of the jet seen in the stacked image at 43 GHz is two times wider than that at 15 GHz, indicating a collimation of the flow within the central 1.5 mas. We estimate the Lorentz factor $\Gamma = 14$, the Doppler factor $\delta=21$, and the viewing angle $\theta = 1.7^\circ$ of the apparent jet base, derive the gradients of magnetic field strength and electron density in the outflow, and the distance between jet apex and the core at each frequency., Comment: Accepted for publication in MNRAS. 18 pages, 18 figures
Published: 2018
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17. A peculiar multi-wavelength flare in the Blazar 3C 454.3

Author: Gupta, Alok C., Mangalam, Arun, Wiita, Paul J., Kushwaha, P., Gaur, H., Zhang, H., Gu, M. F., Liao, M., Dewangan, G., Ho, L. C., Mohan, P., Umeura, M., Sasada, M., Volvach, A. E., Agarwal, A., Aller, M. F., Aller, H. D., Bachev, R., Lahteenmaki, A., Semkov, E., Strigachev, A., Tornikoski, M., and Volvach, L. N.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The blazar 3C454.3 exhibited a strong flare seen in gamma-rays, X-rays, and optical/NIR bands during 3--12 December 2009. Emission in the V and J bands rose more gradually than did the gamma-rays and soft X-rays, though all peaked at nearly the same time. Optical polarization measurements showed dramatic changes during the flare, with a strong anti-correlation between optical flux and degree of polarization (which rose from ~ 3% to ~ 20%) during the declining phase of the flare. The flare was accompanied by large rapid swings in polarization angle of ~ 170 degree. This combination of behaviors appear to be unique. We have cm-band radio data during the same period but they show no correlation with variations at higher frequencies. Such peculiar behavior may be explained using jet models incorporating fully relativistic effects with a dominant source region moving along a helical path or by a shock-in-jet model incorporating three-dimensional radiation transfer if there is a dominant helical magnetic field. We find that spectral energy distributions at different times during the flare can be fit using modified one-zone models where only the magnetic field strength and particle break frequencies and normalizations need change. An optical spectrum taken at nearly the same time provides an estimate for the central black hole mass of ~ 2.3 * 10^9 M_sun. We also consider two weaker flares seen during the $\sim 200$ d span over which multi-band data are available. In one of them, the V and J bands appear to lead the $\gamma$-ray and X-ray bands by a few days; in the other, all variations are simultaneous., Comment: 11 pages, 4 figures, 2 tables; MNRAS in press
Published: 2017
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18. Simultaneous spectra and radio properties of BL Lac's

Author: Mingaliev, M., Sotnikova, Yu., Mufakharov, T., Nieppola, E., Tornikoski, M., Tammi, J., Lahteenmaki, A., Udovitskiy, R., and Erkenov, A.
Subjects: Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the results of nine years of the blazar observing programme at the RATAN-600 radio telescope (2005-2014). The data were obtained at six frequency bands (1.1, 2.3, 4.8, 7.7, 11.2, 21.7 GHz) for 290 blazars, mostly BL Lacs. In addition, we used data at 37 GHz obtained quasi-simultaneously with the Metsahovi radio observatory for some sources. The sample includes blazars of three types: high-synchrotron peaked (HSP), low-synchrotron peaked (LSP), and intermediate-synchrotron peaked (ISP). We present several epochs of flux density measurements, simultaneous radio spectra, spectral indices and properties of their variability. The analysis of the radio properties of different classes of blazars showed that LSP and HSP BL Lac blazars are quite different objects on average. LSPs have higher flux densities, flatter spectra and their variability increases as higher frequencies are considered. On the other hand, HSPs are very faint in radio domain, tend to have steep low frequency spectra, and they are less variable than LSPs at all frequencies. Another result is spectral flattening above 7.7 GHz detected in HSPs, while an average LSP spectrum typically remains flat at both the low and high frequency ranges we considered., Comment: 14 pages, 6 figures. Accepted for publication in Astronomische Nachrichten
Published: 2017
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19. Core shift effect in blazars

Author: Agarwal, A., Mohan, P., Gupta, Alok C., Mangalam, A., Volvach, A. E., Aller, M. F., Aller, H. D., Gu, M. F., Lahteenmaki, A., Tornikoski, M., and Volvach, L. N.
Subjects: Astrophysics - Astrophysics of Galaxies, Astrophysics - High Energy Astrophysical Phenomena
Abstract: We studied the pc-scale core shift effect using radio light curves for three blazars, S5 0716+714, 3C 279 and BL Lacertae, which were monitored at five frequencies ($\nu$) between 4.8 GHz and 36.8 GHz using the University of Michigan Radio Astronomical Observatory (UMRAO), the Crimean Astrophysical Observatory (CrAO), and Metsahovi Radio Observatory for over 40 years. Flares were Gaussian fitted to derive time delays between observed frequencies for each flare ($\Delta t$), peak amplitude ($A$), and their half width. Using $A \propto \nu^{\alpha}$ we infer $\alpha$ in the range $-$16.67 to 2.41 and using $\Delta t \propto \nu^{1/k_r}$, we infer $k_r \sim 1$, employed in the context of equipartition between magnetic and kinetic energy density for parameter estimation. From the estimated core position offset ($\Omega_{r \nu}$) and the core radius ($r_{\rm core}$), we infer that opacity model may not be valid in all cases. The mean magnetic field strength at 1 pc ($B_1$) and at the core ($B_{\rm core}$), are in agreement with previous estimates. We apply the magnetically arrested disk model to estimate black hole spins in the range $0.15-0.9$ for these blazars, indicating that the model is consistent with expected accretion mode in such sources. The power law shaped power spectral density has slopes $-$1.3 to $-$2.3 and is interpreted in terms of multiple shocks or magnetic instabilities., Comment: 21 pages, 17 figures, 12 tables. Accepted for publication in MNRAS
Published: 2017
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20. Planck intermediate results LIV. The Planck multi-frequency catalogue of non-thermal sources

Author: Akrami, Y, Argueso, F, Ashdown, M, Aumont, J, Baccigalupi, C, Ballardini, M, Banday, AJ, Barreiro, RB, Bartolo, N, Basak, S, Benabed, K, Bernard, J-P, Bersanelli, M, Bielewicz, P, Bonavera, L, Bond, JR, Borrill, J, Bouchet, FR, Burigana, C, Butler, RC, Calabrese, E, Carron, J, Chiang, HC, Combet, C, Crill, BP, Cuttaia, F, de Bernardis, P, de Rosa, A, de Zotti, G, Delabrouille, J, Delouis, J-M, Di Valentino, E, Dickinson, C, Diego, JM, Ducout, A, Dupac, X, Efstathiou, G, Elsner, F, Ensslin, TA, Eriksen, HK, Fantaye, Y, Finelli, F, Frailis, M, Fraisse, AA, Franceschi, E, Frolov, A, Galeotta, S, Galli, S, Ganga, K, Genova-Santos, RT, Gerbino, M, Ghosh, T, Gonzalez-Nuevo, J, Gorski, KM, Gratton, S, Gruppuso, A, Gudmundsson, JE, Handley, W, Hansen, FK, Herranz, D, Hivon, E, Huang, Z, Jaffe, AH, Jones, WC, Keihanen, E, Keskitalo, R, Kiiveri, K, Kim, J, Kisner, TS, Krachmalnicoff, N, Kunz, M, Kurki-Suonio, H, Lahteenmaki, A, Lamarre, J-M, Lasenby, A, Lattanzi, M, Lawrence, CR, Levrier, F, Liguori, M, Lilje, PB, Lindholm, V, Lopez-Caniego, M, Ma, Y-Z, Macias-Perez, JF, Maggio, G, Maino, D, Mandolesi, N, Mangilli, A, Maris, M, Martin, PG, Martinez-Gonzalez, E, Matarrese, S, McEwen, JD, Meinhold, PR, Melchiorri, A, Mennella, A, Migliaccio, M, Miville-Deschenes, M-A, Molinari, D, and Moneti, A
Subjects: catalogs, cosmology: observations, radio continuum: general, submillimeter: general, Astronomical And Space Sciences, Astronomy & Astrophysics, Astronomical and Space Sciences
Abstract: Context. The European Space Agency (ESA) Rosetta mission was the most comprehensive study of a comet ever performed. In particular, the Rosetta orbiter, which carried many instruments for monitoring the evolution of the dusty gas emitted by the cometary nucleus, returned an enormous volume of observational data collected from the close vicinity of the nucleus of comet 67P/Churyumov-Gerasimenko.Aims. Such data are expected to yield unique information on the physical processes of gas and dust emission, using current physical model fits to the data. We present such a model (the RZC model) and our procedure of adjustment of this model to the data.Methods. The RZC model consists of two components: (1) a numerical three-dimensional time-dependent code solving the Eulerian/Navier-Stokes equations governing the gas outflow, and a direct simulation Monte Carlo (DSMC) gaskinetic code with the same objective; and (2) an iterative procedure to adjust the assumed model parameters to best-fit the observational data at all times.Results. We demonstrate that our model is able to reproduce the overall features of the local neutral number density and composition measurements of Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) Comet Pressure Sensor (COPS) and Double Focusing Mass Spectrometer (DFMS) instruments in the period August 1–November 30, 2014. The results of numerical simulations show that illumination conditions on the nucleus are the main driver for the gas activity of the comet. We present the distribution of surface inhomogeneity best-fitted to the ROSINA COPS and DFMS in situ measurements.
Published: 2018

21. Urban wireless traffic evolution: the role of new devices and the effect of policy.

Author: Jaume Benseny, Jarno Lahteenmaki, Juuso Töyli, and Heikki Hämmäinen
Published: 2023
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22. Multi-Wavelength Observations of the Blazar 1ES 1011+496 in Spring 2008

Author: The MAGIC Collaboration, Ahnen, M. L., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Banerjee, B., Bangale, P., de Almeida, U. Barres, Barrio, J. A., Gonzalez, J. Becerra, Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Chatterjee, A., Clavero, R., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., Wilhelmi, E. de Ona, Mendez, C. Delgado, Di Pierro, F., Prester, D. Dominis, Dorner, D., Doro, M., Einecke, S., Elsaesser, D., Fernandez-Barral, A., Fidalgo, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., Lopez, R. J. Garcia, Garczarczyk, M., Terrats, D. Garrido, Gaug, M., Giammaria, P., Glawion, D., Godinovic, N., Munoz, A. Gonzalez, Guberman, D., Hanabata, Y., Hayashida, M., Herrera, J., Hose, J., Hrupec, D., Hughes, G., Idec, W., Kodani, K., Konno, Y., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lindfors, E., Lombardi, S., Longo, F., Lopez, M., Lopez-Coto, R., Lopez-Oramas, A., Lorenz, E., Majumdar, P., Makariev, M., Mallot, K., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martinez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Nakajima, D., Neustroev, V., Niedzwiecki, A., Rosillo, M. Nievas, Nilsson, K., Nishijima, K., Noda, K., Orito, R., Overkemping, A., Paiano, S., Palacio, J., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes-Fortuny, X., Persic, M., Poutanen, J., Moroni, P. G. Prada, Prandini, E., Puljak, I., Reinthal, R., Rhode, W., Ribo, M., Rico, J., Garcia, J. Rodriguez, Rugamer, S., Saito, T., Satalecka, K., Scapin, V., Schultz, C., Schweizer, T., Shore, S. N., Sillanpaa, A., Sitarek, J., Snidaric, I., Sobczynska, D., Stamerra, A., Steinbring, T., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzic, T., Tescaro, D., Teshima, M., Thaele, J., Torres, D. F., Toyama, T., Treves, A., Verguilov, V., Vovk, I., Ward, J. E., Will, M., Wu, M. H., Zanin, R., Lucarelli, F., Pittori, C., Vercellone, S., Berdyugin, A., Carini, M. T., Lahteenmaki, A., Pasanen, M., Pease, A., Sainio, J., Tornikoski, M., and Walters, R.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The BL Lac object 1ES 1011+496 was discovered at Very High Energy gamma-rays by MAGIC in spring 2007. Before that the source was little studied in different wavelengths. Therefore a multi-wavelength (MWL) campaign was organized in spring 2008. Along MAGIC, the MWL campaign included the Metsahovi radio observatory, Bell and KVA optical telescopes and the Swift and AGILE satellites. MAGIC observations span from March to May, 2008 for a total of 27.9 hours, of which 19.4 hours remained after quality cuts. The light curve showed no significant variability. The differential VHE spectrum could be described with a power-law function. Both results were similar to those obtained during the discovery. Swift XRT observations revealed an X-ray flare, characterized by a harder when brighter trend, as is typical for high synchrotron peak BL Lac objects (HBL). Strong optical variability was found during the campaign, but no conclusion on the connection between the optical and VHE gamma-ray bands could be drawn. The contemporaneous SED shows a synchrotron dominated source, unlike concluded in previous work based on nonsimultaneous data, and is well described by a standard one zone synchrotron self Compton model. We also performed a study on the source classification. While the optical and X-ray data taken during our campaign show typical characteristics of an HBL, we suggest, based on archival data, that 1ES 1011+496 is actually a borderline case between intermediate and high synchrotron peak frequency BL Lac objects., Comment: 13 pages, accepted for publication in MNRAS
Published: 2016
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23. First NuSTAR Observations of Mrk 501 within a Radio to TeV Multi-Instrument Campaign

Author: Furniss, A., Noda, K., Boggs, S., Chiang, J., Christensen, F., Craig, W., Giommi, P ., Hailey, C., Harisson, F., Madejski, G., Nalewajko, K., Perri, M., Stern, D., Urry, M., Verrecchia, F., Zhang, W., Ahnen, M. L., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Banerjee, B., Bangale, P., de Almeida, U. Barres, Barrio, J. A., Gonzalez, J. Becerra, Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Chatterjee, A., Clavero, R., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., Wilhelmi, E. de Ona, Mendez, C. Delgado, Di Pierro, F., Prester, D. Dominis, Dorner, D., Doro, M., Einecke, S., Glawion, D. Eisenacher, Elsaesser, D., Fernandez-Barral, A., Fidalgo, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., Lopez, R. J. Garcia, Garczarczyk, M., Terrats, D. Garrido, Gaug, M., Giammaria, P., Godinovic, N., Munoz, A. Gonzalez, Guberman, D., Hanabata, Y., Hayashida, M., Herrera, J., Hose, J., Hrupec, D., Hughes, G., Idec, W., Kellermann, H., Kodani, K., Konno, Y., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lewandowska, N., Lindfors, E., Lombardi, S., Longo, F., Lopez, M., Lopez-Coto, R., Lopez-Oramas, A., Lorenz, E., Majumdar, P., Makariev, M., Mallot, K., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martinez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Nakajima, D., Neustroev, V., Niedzwiecki, A., Rosillo, M. Nievas, Nilsson, K., Nishijima, K., Orito, R., Overkemping, A., Paiano, S., Palacio, J., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes-Fortuny, X., Persic, M., Poutanen, J., Moroni, P. G. Prada, Prandini, E., Puljak, I., Reinthal, R., Rhode, W., Ribo, M., Rico, J., Garcia, J. Rodriguez, Saito, T., Saito, K., Satalecka, K., Scapin, V., Schultz, C., Schweizer, T., Shore, S. N., Sillanpaa, A., Sitarek, J., Snidaric, I., Sobczynska, D., Stamerra, A., Steinbring, T., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzic, T., Tescaro, D., Teshima, M., Thaele, J., Torres, D. F., Toyama, T., Treves, A., Verguilov, V., Vovk, I., Will, M., Zanin, R., Archer, A., Benbow, W., Bird, R., Biteau, J., Bugaev, V., Cardenzana, J. V, Cerruti, M., Chen, X., Ciupik, L., Connolly, M. P., Cui, W., Dickinson, H. J., Dumm, J., Eisch, J. D., Falcone, A., Feng, Q., Finley, J. P., Fleischhack, H., Fortin, P., Fortson, L., Gerard, L., Gillanders, G. H., Griffin, S., Griffiths, S. T., Grube, J., Gyuk, G., Haakansson, N., Holder, J., Humensky, T. B., Johnson, C. A., Kaaret, P., Kertzman, M., Kieda, D., Krause, M., Krennrich, F., Lang, M. J., Lin, T. T. Y., Maier, G., McArthur, S., McCann, A., Meagher, K., Moriarty, P., Mukherjee, R., Nieto, D., de Bhroithe, A. O'Faolain, Ong, R. A., Park, N., Petry, D., Pohl, M., Popkow, A., Ragan, K., Ratliff, G., Reyes, L. C., Reynolds, P. T., Richards, G. T., Roache, E., Santander, M., Sembroski, G. H., Shahinyan, K., Staszak, D., Telezhinsky, I., Tucci, J. V., Tyler, J., Vassiliev, V. V., Wakely, S. P., Weiner, O. M., Weinstein, A., Wilhelm, A., Williams, D. A., Zitzer, B., Fuhrmann, O. Vince L., Angelakis, E., Karamanavis, V., Myserlis, I., Krichbaum, T. P., Zensus, J. A., Ungerechts, H., Sievers, A., Bachev, R., Bottcher, M., Chen, W. P., Damljanovic, G., Eswaraiah, C., Guver, T., Hovatta, T., Hughes, Z., Ibryamov, S. . I., Joner, M. D., Jordan, B., Jorstad, S. G., Joshi, M., Kataoka, J., Kurtanidze, O. M., Kurtanidze, S. O., Lahteenmaki, A., Latev, G., Lin, H. C., Larionov, V. M., Mokrushina, A. A., Morozova, D. A., Nikolashvili, M. G., Raiteri, C. M., Ramakrishnan, V., Readhead, A. C. R., Sadun, A. C., Sigua, L. A., Semkov, E. H., Strigachev, A., Tammi, J., Tornikoski, M., Troitsky, Y. V. Troitskaya I. S., and Villata, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report on simultaneous broadband observations of the TeV-emitting blazar Markarian 501 between 1 April and 10 August 2013, including the first detailed characterization of the synchrotron peak with Swift and NuSTAR. During the campaign, the nearby BL Lac object was observed in both a quiescent and an elevated state. The broadband campaign includes observations with NuSTAR, MAGIC, VERITAS, the Fermi Large Area Telescope (LAT), Swift X-ray Telescope and UV Optical Telescope, various ground-based optical instruments, including the GASP-WEBT program, as well as radio observations by OVRO, Mets\"ahovi and the F-Gamma consortium. Some of the MAGIC observations were affected by a sand layer from the Saharan desert, and had to be corrected using event-by-event corrections derived with a LIDAR (LIght Detection And Ranging) facility. This is the first time that LIDAR information is used to produce a physics result with Cherenkov Telescope data taken during adverse atmospheric conditions, and hence sets a precedent for the current and future ground-based gamma-ray instruments. The NuSTAR instrument provides unprecedented sensitivity in hard X-rays, showing the source to display a spectral energy distribution between 3 and 79 keV consistent with a log-parabolic spectrum and hard X-ray variability on hour timescales. None (of the four extended NuSTAR observations) shows evidence of the onset of inverse-Compton emission at hard X-ray energies. We apply a single-zone equilibrium synchrotron self-Compton model to five simultaneous broadband spectral energy distributions. We find that the synchrotron self-Compton model can reproduce the observed broadband states through a decrease in the magnetic field strength coinciding with an increase in the luminosity and hardness of the relativistic leptons responsible for the high-energy emission., Comment: Accepted for publication in ApJ
Published: 2015
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24. Planck 2013 results. XXXI. Consistency of the Planck data

Author: Planck Collaboration, Ade, P. A. R., Arnaud, M., Aumont, J., Baccigalupi, C., Banday, A. J., Barreiro, R. B., Battaner, E., Benabed, K., Benoit-Levy, A., Bernard, J. -P., Bersanelli, M., Bielewicz, P., Bond, J. R., Borrill, J., Bouchet, F. R., Burigana, C., Cardoso, J. -F., Catalano, A., Challinor, A., Chamballu, A., Chiang, H. C., Christensen, R., Clements, D. L., Colombi, S., Colombo, L. P. L., Couchot, F., Coulais, A., Crill, B. P., Curto, A., Cuttaia, F., Danese, L., Davies, R. D., Davis, R. J., de Bernardis, P., de Rosa, A., de Zotti, G., Delabrouille, J., Desert, F. -X., Dickinson, C., Diego, J. M., Dole, H., Donzelli, S., Dore, O., Douspis, M., Dupac, X., Ensslin, T. A., Eriksen, H. K., Finelli, F., Forni, O., Frailis, M., Fraisse, A. A., Franceschi, E., Galeotta, S., Ganga, K., Giard, M., Gonzalez-Nuevo, J., Gorski, K. M., Gratton, S., Gregorio, A., Gruppuso, A., Gudmundsson, J. E., Hansen, F. K., Hanson, D., Harrison, D. L., Henrot-Versille, S., Herranz, C. D., Hildebrandt, S. R., Hivon, E., Hobson, M., Holmes, W. A., Hornstrup, A., Hovest, W., Huffenberger, K. M., Jaffe, A. H., Jaffe, T. R., Jones, W. C., Keihanen, E., Keskitalo, R., Knoche, J., Kunz, M., Kurki-Suonio, H., Lagache, G., Lahteenmaki, A., Lamarre, J. -M., Lasenby, A., Lattanzi, M., Lawrence, C. R., Leonardi, R., Leon-Tavares, J., Lesgourgues, J., Liguori, M., Lilje, P. B., Lilley, M., Linden-Vornle, M., Lopez-Caniego, M., Lubin, P. M., Macias-Perez, J. F., Maino, D., Mandolesi, N., Maris, M., Martin, P. G., Martinez-Gonzalez, E., Masi, S., Matarrese, S., Mazzotta, P., Meinhold, P. R., Melchiorri, A., Mendes, L., Mennella, A., Mitra, S., Miville-Deschenes, M. -A., Moneti, A., Montier, L., Morgante, G., Mortlock, D., Moss, A., Munshi, D., Murphy, J. A., Naselsky, P., Nati, F., Natoli, P., Norgaard-Nielsen, H. U., Noviello, F., Novikov, D., Novikov, I., Oxborrow, C. A., Pagano, L., Pajot, F., Paoletti, D., Partridge, B., Pasian, F., Patanchon, G., Pearson, D., Pearson, T. J., Perdereau, O., Perrotta, F., Piacentini, F., Piat, M., Pierpaoli, E., Pietrobon, D., Plaszczynski, S., Pointecouteau, E., Polenta, G., Popa, L., Pratt, G. W., Prunet, S., Puget, J. -L., Rachen, J. P., Reinecke, M., Remazeilles, M., Renault, C., Ricciardi, S., Ristorcelli, I., Rocha, G., Roudier, G., Rubino-Martin, J. A., Rusholme, B., Sandri, M., Scott, D., Stolyarov, V., Sudiwala, R., Sutton, D., Suur-Uski, A. -S., Sygnet, J. -F., Tauber, J. A., Terenzi, L., Toffolatti, L., Tomasi, M., Tristram, M., Tucci, M., Valenziano, L., Valiviita, J., Van Tent, B., Vielva, P., Villa, F., Wade, L. A., Wandelt, B. D., Wehus, I. K., White, S. D. M., Yvon, D., Zacchei, A., and Zonca, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The Planck design and scanning strategy provide many levels of redundancy that can be exploited to provide tests of internal consistency. One of the most important is the comparison of the 70GHz and 100GHz channels. Based on different instrument technologies, with feeds located differently in the focal plane, analysed independently by different teams using different software, and near the minimum of diffuse foreground emission, these channels are in effect two different experiments. The 143GHz channel has the lowest noise level on Planck, and is near the minimum of unresolved foreground emission. In this paper, we analyse the level of consistency achieved in the 2013 Planck data. We concentrate on comparisons between the 70/100/143GHz channel maps and power spectra, particularly over the angular scales of the first and second acoustic peaks, on maps masked for diffuse Galactic emission and for strong unresolved sources. Difference maps covering angular scales from 8deg-15arcmin are consistent with noise, and show no evidence of cosmic microwave background structure. Including small but important corrections for unresolved-source residuals, we demonstrate agreement between 70 and 100GHz power spectra averaged over 70
Published: 2015
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25. Optical and Radio Variability of BL Lacertae

Author: Gaur, Haritma, Gupta, Alok C., Bachev, R., Strigachev, A., Semkov, E., Wiita, Paul J., Volvach, A. E., Gu, Minfeng, Agarwal, A., Agudo, I., Aller, M. F., Aller, H. D., Kurtanidze, O. M., Kurtanidze, S. O., Lahteenmaki, A., Peneva, S., Nikolashvili, M. G., Sigua, L. A., Tornikoski, M., and Volvach, L. N.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We observed the prototype blazar, BL Lacertae, extensively in optical and radio bands during an active phase in the period 2010--2013 when the source showed several prominent outbursts. We searched for possible correlations and time lags between the optical and radio band flux variations using multifrequency data to learn about the mechanisms producing variability. During an active phase of BL Lacertae, we searched for possible correlations and time lags between multifrequency light curves of several optical and radio bands. We tried to estimate any possible variability timescales and inter-band lags in these bands. We performed optical observations in B, V, R and I bands from seven telescopes in Bulgaria, Georgia, Greece and India and obtained radio data at 36.8, 22.2, 14.5, 8 and 4.8 GHz frequencies from three telescopes in Ukraine, Finland and USA. Significant cross-correlations between optical and radio bands are found in our observations with a delay of cm-fluxes with respect to optical ones of ~250 days. The optical and radio light curves do not show any significant timescales of variability. BL Lacertae showed many optical 'mini-flares' on short time-scales. Variations on longer term timescales are mildly chromatic with superposition of many strong optical outbursts. In radio bands, the amplitude of variability is frequency dependent. Flux variations at higher radio frequencies lead the lower frequencies by days or weeks. The optical variations are consistent with being dominated by a geometric scenario where a region of emitting plasma moves along a helical path in a relativistic jet. The frequency dependence of the variability amplitude supports an origin of the observed variations intrinsic to the source., Comment: 10 pages, 9 figures, Accepted for publication in A&A
Published: 2015
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26. Frequency dependent core shifts and parameter estimation for the blazar 3C 454.3

Author: Mohan, P., Agarwal, A., Mangalam, A., Gupta, Alok C., Wiita, Paul J., Volvach, A. E., Aller, M. F., Aller, H. D., Gu, M. F., Lahteenmaki, A., Tornikoski, M., and Volvach, L. N.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We study the core shift effect in the parsec scale jet of the blazar 3C 454.3 using the 4.8 GHz - 36.8 GHz radio light curves obtained from three decades of continuous monitoring. From a piecewise Gaussian fit to each flare, time lags $\Delta t$ between the observation frequencies $\nu$ and spectral indices $\alpha$ based on peak amplitudes $A$ are determined. From the fit $\Delta t \propto \nu^{1/k_r}$, $k_r = 1.10 \pm 0.18$ indicating equipartition between the magnetic field energy density and the particle energy density. From the fit $A \propto \nu^\alpha$, $\alpha$ is in the range $-0.24$ to $1.52$. A mean magnetic field strength at 1 pc, $B_1 = 0.5 \pm 0.2$ G, and at the core, $B_{\rm core} = 46 \pm 16$ mG, are inferred, consistent with previous estimates. The measure of core position offset is $\Omega_{r\nu} = 6.4 \pm 2.8$ pc GHz$^{1/k_r}$ when averaged over all frequency pairs. Based on the statistical trend shown by the measured core radius $r_{\rm core}$ as a function of $\nu$, we infer that the synchrotron opacity model may not be valid for all cases. A Fourier periodogram analysis yields power law slopes in the range $-1.6$ to $-3.5$ describing the power spectral density shape and gives bend timescales in the range $0.52 - 0.66~$yr. This result, and both positive and negative $\alpha$, indicate that the flares originate from multiple shocks in a small region. Important objectives met in our study include: the demonstration of the computational efficiency and statistical basis of the piecewise Gaussian fit; consistency with previously reported results; evidence for the core shift dependence on observation frequency and its utility in jet diagnostics in the region close to the resolving limit of very long baseline interferometry observations., Comment: 12 pages, 11 figures (23 sub-figures), 5 tables. Accepted for publication in MNRAS
Published: 2015
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27. Planck 2015 results. XXV. Diffuse low-frequency Galactic foregrounds

Author: Planck Collaboration, Ade, P. A. R., Aghanim, N., Alves, M. I. R., Arnaud, M., Ashdown, M., Aumont, J., Baccigalupi, C., Banday, A. J., Barreiro, R. B., Bartlett, J. G., Bartolo, N., Battaner, E., Benabed, K., Benoit, A., Benoit-Levy, A., Bernard, J. -P., Bersanelli, M., Bielewicz, P., Bock, J. J., Bonaldi, A., Bonavera, L., Bond, J. R., Borrill, J., Bouchet, F. R., Boulanger, F., Bucher, M., Burigana, C., Butler, R. C., Calabrese, E., Cardoso, J. -F., Catalano, A., Challinor, A., Chamballu, A., Chary, R. -R., Chiang, H. C., Christensen, P. R., Colombi, S., Colombo, L. P. L., Combet, C., Couchot, F., Coulais, A., Crill, B. P., Curto, A., Cuttaia, F., Danese, L., Davies, R. D., Davis, R. J., de Bernardis, P., de Rosa, A., de Zotti, G., Delabrouille, J., Delouis, J. -M., Desert, F. -X., Dickinson, C., Diego, J. M., Dole, H., Donzelli, S., Dore, O., Douspis, M., Ducout, A., Dupac, X., Efstathiou, G., Elsner, F., Ensslin, T. A., Eriksen, H. K., Falgarone, E., Fergusson, J., Finelli, F., Forni, O., Frailis, M., Fraisse, A. A., Franceschi, E., Frejsel, A., Galeotta, S., Galli, S., Ganga, K., Ghosh, T., Giard, M., Giraud-Heraud, Y., Gjerlow, E., Gonzalez-Nuevo, J., Gorski, K. M., Gratton, S., Gregorio, A., Gruppuso, A., Gudmundsson, J. E., Hansen, F. K., Hanson, D., Harrison, D. L., Helou, G., Henrot-Versille, S., Hernandez-Monteagudo, C., Herranz, D., Hildebrandt, S. R., Hivon, E., Hobson, M., Holmes, W. A., Hornstrup, A., Hovest, W., Huffenberger, K. M., Hurier, G., Jaffe, A. H., Jaffe, T. R., Jones, W. C., Juvela, M., Keihanen, E., Keskitalo, R., Kisner, T. S., Kneissl, R., Knoche, J., Kunz, M., Kurki-Suonio, H., Lagache, G., Lahteenmaki, A., Lamarre, J. -M., Lasenby, A., Lattanzi, M., Lawrence, C. R., Leahy, J. P., Leonardi, R., Lesgourgues, J., Levrier, F., Liguori, M., Lilje, P. B., Linden-Vornle, M., Lopez-Caniego, M., Lubin, P. M., Macias-Perez, J. F., Maggio, G., Maino, D., Mandolesi, N., Mangilli, A., Maris, M., Marshall, D. J., Martin, P. G., Martinez-Gonzalez, E., Masi, S., Matarrese, S., McGehee, P., Meinhold, P. R., Melchiorri, A., Mendes, L., Mennella, A., Migliaccio, M., Mitra, S., Miville-Deschenes, M. -A., Moneti, A., Montier, L., Morgante, G., Mortlock, D., Moss, A., Munshi, D., Murphy, J. A., Naselsky, P., Nati, F., Natoli, P., Netterfield, C. B., Norgaard-Nielsen, H. U., Noviello, F., Novikov, D., Novikov, I., Orlando, E., Oxborrow, C. A., Paci, F., Pagano, L., Pajot, F., Paladini, R., Paoletti, D., Partridge, B., Pasian, F., Patanchon, G., Pearson, T. J., Peel, M., Perdereau, O., Perotto, L., Perrotta, F., Pettorino, V., Piacentini, F., Piat, M., Pierpaoli, E., Pietrobon, D., Plaszczynski, S., Pointecouteau, E., Polenta, G., Pratt, G. W., Prezeau, G., Prunet, S., Puget, J. -L., Rachen, J. P., Reach, W. T., Rebolo, R., Reinecke, M., Remazeilles, M., Renault, C., Renzi, A., Ristorcelli, I., Rocha, G., Rosset, C., Rossetti, M., Roudier, G., Rubino-Martin, J. A., Rusholme, B., Sandri, M., Santos, D., Savelainen, M., Savini, G., Scott, D., Seiffert, M. D., Shellard, E. P. S., Spencer, L. D., Stolyarov, V., Stompor, R., Strong, A. W., Sudiwala, R., Sunyaev, R., Sutton, D., Suur-Uski, A. -S., Sygnet, J. -F., Tauber, J. A., Terenzi, L., Toffolatti, L., Tomasi, M., Tristram, M., Tucci, M., Tuovinen, J., Umana, G., Valenziano, L., Valiviita, J., Van Tent, B., Vidal, M., Vielva, P., Villa, F., Wade, L. A., Wandelt, B. D., Watson, R., Wehus, I. K., Wilkinson, A., Yvon, D., Zacchei, A., and Zonca, A.
Subjects: Astrophysics - Astrophysics of Galaxies
Abstract: (abridged) We discuss the Galactic foreground emission between 20 and 100GHz based on observations by Planck/WMAP. The Commander component-separation tool has been used to separate the various astrophysical processes in total intensity. Comparison with RRL templates verifies the recovery of the free-free emission along the Galactic plane. Comparison of the high-latitude Halpha emission with our free-free map shows residuals that correlate with dust optical depth, consistent with a fraction (~30%) of Halpha having been scattered by high-latitude dust. We highlight a number of diffuse spinning dust morphological features at high latitude. There is substantial spatial variation in the spinning dust spectrum, with the emission peak ranging from below 20GHz to more than 50GHz. There is a strong tendency for the spinning dust component near many prominent HII regions to have a higher peak frequency, suggesting that this increase in peak frequency is associated with dust in the photodissociation regions around the nebulae. The emissivity of spinning dust in these diffuse regions is of the same order as previous detections in the literature. Over the entire sky, the commander solution finds more anomalous microwave emission than the WMAP component maps, at the expense of synchrotron and free-free emission. This can be explained by the difficulty in separating multiple broadband components with a limited number of frequency maps. Future surveys (5-20GHz), will greatly improve the separation by constraining the synchrotron spectrum. We combine Planck/WMAP data to make the highest S/N ratio maps yet of the intensity of the all-sky polarized synchrotron emission at frequencies above a few GHz. Most of the high-latitude polarized emission is associated with distinct large-scale loops and spurs, and we re-discuss their structure..., Comment: Planck collaboration paper XXV from 2015 results. Accepted for publication in A&A. Corresponding authors: Clive Dickinson and Paddy Leahy. 46 pages, 33 figures
Published: 2015
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28. Planck 2015 results. XX. Constraints on inflation

Author: Planck Collaboration, Ade, P. A. R., Aghanim, N., Arnaud, M., Arroja, F., Ashdown, M., Aumont, J., Baccigalupi, C., Ballardini, M., Banday, A. J., Barreiro, R. B., Bartolo, N., Battaner, E., Benabed, K., Benoit, A., Benoit-Levy, A., Bernard, J. -P., Bersanelli, M., Bielewicz, P., Bock, J. J., Bonaldi, A., Bonavera, L., Bond, J. R., Borrill, J., Bouchet, F. R., Boulanger, F., Bucher, M., Burigana, C., Butler, R. C., Calabrese, E., Cardoso, J. -F., Catalano, A., Challinor, A., Chamballu, A., Chary, R. -R., Chiang, H. C., Christensen, P. R., Church, S., Clements, D. L., Colombi, S., Colombo, L. P. L., Combet, C., Contreras, D., Couchot, F., Coulais, A., Crill, B. P., Curto, A., Cuttaia, F., Danese, L., Davies, R. D., Davis, R. J., de Bernardis, P., de Rosa, A., de Zotti, G., Delabrouille, J., Desert, F. -X., Diego, J. M., Dole, H., Donzelli, S., Dore, O., Douspis, M., Ducout, A., Dupac, X., Efstathiou, G., Elsner, F., Ensslin, T. A., Eriksen, H. K., Fergusson, J., Finelli, F., Forni, O., Frailis, M., Fraisse, A. A., Franceschi, E., Frejsel, A., Frolov, A., Galeotta, S., Galli, S., Ganga, K., Gauthier, C., Giard, M., Giraud-Heraud, Y., Gjerlow, E., Gonzalez-Nuevo, J., Gorski, K. M., Gratton, S., Gregorio, A., Gruppuso, A., Gudmundsson, J. E., Hamann, J., Handley, W., Hansen, F. K., Hanson, D., Harrison, D. L., Henrot-Versille, S., Hernandez-Monteagudo, C., Herranz, D., Hildebrandt, S. R., Hivon, E., Hobson, M., Holmes, W. A., Hornstrup, A., Hovest, W., Huang, Z., Huffenberger, K. M., Hurier, G., Jaffe, A. H., Jaffe, T. R., Jones, W. C., Juvela, M., Keihanen, E., Keskitalo, R., Kim, J., Kisner, T. S., Kneissl, R., Knoche, J., Kunz, M., Kurki-Suonio, H., Lagache, G., Lahteenmaki, A., Lamarre, J. -M., Lasenby, A., Lattanzi, M., Lawrence, C. R., Leonardi, R., Lesgourgues, J., Levrier, F., Lewis, A., Liguori, M., Lilje, P. B., Linden-Vornle, M., Lopez-Caniego, M., Lubin, P. M., Ma, Y. -Z., Macias-Perez, J. F., Maggio, G., Maino, D., Mandolesi, N., Mangilli, A., Maris, M., Martin, P. G., Martinez-Gonzalez, E., Masi, S., Matarrese, S., McGehee, P., Meinhold, P. R., Melchiorri, A., Mendes, L., Mennella, A., Migliaccio, M., Mitra, S., Miville-Deschenes, M. -A., Molinari, D., Moneti, A., Montier, L., Morgante, G., Mortlock, D., Moss, A., Munchmeyer, M., Munshi, D., Murphy, J. A., Naselsky, P., Nati, F., Natoli, P., Netterfield, C. B., Norgaard-Nielsen, H. U., Noviello, F., Novikov, D., Novikov, I., Oxborrow, C. A., Paci, F., Pagano, L., Pajot, F., Paladini, R., Pandolfi, S., Paoletti, D., Pasian, F., Patanchon, G., Pearson, T. J., Peiris, H. V., Perdereau, O., Perotto, L., Perrotta, F., Pettorino, V., Piacentini, F., Piat, M., Pierpaoli, E., Pietrobon, D., Plaszczynski, S., Pointecouteau, E., Polenta, G., Popa, L., Pratt, G. W., Prezeau, G., Prunet, S., Puget, J. -L., Rachen, J. P., Reach, W. T., Rebolo, R., Reinecke, M., Remazeilles, M., Renault, C., Renzi, A., Ristorcelli, I., Rocha, G., Rosset, C., Rossetti, M., Roudier, G., Rowan-Robinson, M., Rubino-Martin, J. A., Rusholme, B., Sandri, M., Santos, D., Savelainen, M., Savini, G., Scott, D., Seiffert, M. D., Shellard, E. P. S., Shiraishi, M., Spencer, L. D., Stolyarov, V., Stompor, R., Sudiwala, R., Sunyaev, R., Sutton, D., Suur-Uski, A. -S., Sygnet, J. -F., Tauber, J. A., Terenzi, L., Toffolatti, L., Tomasi, M., Tristram, M., Trombetti, T., Tucci, M., Tuovinen, J., Valenziano, L., Valiviita, J., Van Tent, B., Vielva, P., Villa, F., Wade, L. A., Wandelt, B. D., Wehus, I. K., White, M., Yvon, D., Zacchei, A., Zibin, J. P., and Zonca, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present the implications for cosmic inflation of the Planck measurements of the cosmic microwave background (CMB) anisotropies in both temperature and polarization based on the full Planck survey. The Planck full mission temperature data and a first release of polarization data on large angular scales measure the spectral index of curvature perturbations to be $n_\mathrm{s} = 0.968 \pm 0.006$ and tightly constrain its scale dependence to $d n_s/d \ln k =-0.003 \pm 0.007$ when combined with the Planck lensing likelihood. When the high-$\ell$ polarization data is included, the results are consistent and uncertainties are reduced. The upper bound on the tensor-to-scalar ratio is $r_{0.002} < 0.11$ (95% CL), consistent with the B-mode polarization constraint $r< 0.12$ (95% CL) obtained from a joint BICEP2/Keck Array and Planck analysis. These results imply that $V(\phi) \propto \phi^2$ and natural inflation are now disfavoured compared to models predicting a smaller tensor-to-scalar ratio, such as $R^2$ inflation. Three independent methods reconstructing the primordial power spectrum are investigated. The Planck data are consistent with adiabatic primordial perturbations. We investigate inflationary models producing an anisotropic modulation of the primordial curvature power spectrum as well as generalized models of inflation not governed by a scalar field with a canonical kinetic term. The 2015 results are consistent with the 2013 analysis based on the nominal mission data., Comment: 68 pages, 59 figures, 18 tables; updates to match the published version
Published: 2015
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29. Planck 2015 results. XIII. Cosmological parameters

Author: Planck Collaboration, Ade, P. A. R., Aghanim, N., Arnaud, M., Ashdown, M., Aumont, J., Baccigalupi, C., Banday, A. J., Barreiro, R. B., Bartlett, J. G., Bartolo, N., Battaner, E., Battye, R., Benabed, K., Benoit, A., Benoit-Levy, A., Bernard, J. -P., Bersanelli, M., Bielewicz, P., Bock, J. J., Bonaldi, A., Bonavera, L., Bond, J. R., Borrill, J., Bouchet, F. R., Boulanger, F., Bucher, M., Burigana, C., Butler, R. C., Calabrese, E., Cardoso, J. -F., Catalano, A., Challinor, A., Chamballu, A., Chary, R. -R., Chiang, H. C., Chluba, J., Christensen, P. R., Church, S., Clements, D. L., Colombi, S., Colombo, L. P. L., Combet, C., Coulais, A., Crill, B. P., Curto, A., Cuttaia, F., Danese, L., Davies, R. D., Davis, R. J., de Bernardis, P., de Rosa, A., de Zotti, G., Delabrouille, J., Desert, F. -X., Di Valentino, E., Dickinson, C., Diego, J. M., Dolag, K., Dole, H., Donzelli, S., Dore, O., Douspis, M., Ducout, A., Dunkley, J., Dupac, X., Efstathiou, G., Elsner, F., Ensslin, T. A., Eriksen, H. K., Farhang, M., Fergusson, J., Finelli, F., Forni, O., Frailis, M., Fraisse, A. A., Franceschi, E., Frejsel, A., Galeotta, S., Galli, S., Ganga, K., Gauthier, C., Gerbino, M., Ghosh, T., Giard, M., Giraud-Heraud, Y., Giusarma, E., Gjerlow, E., Gonzalez-Nuevo, J., Gorski, K. M., Gratton, S., Gregorio, A., Gruppuso, A., Gudmundsson, J. E., Hamann, J., Hansen, F. K., Hanson, D., Harrison, D. L., Helou, G., Henrot-Versille, S., Hernandez-Monteagudo, C., Herranz, D., Hildebrandt, S. R., Hivon, E., Hobson, M., Holmes, W. A., Hornstrup, A., Hovest, W., Huang, Z., Huffenberger, K. M., Hurier, G., Jaffe, A. H., Jaffe, T. R., Jones, W. C., Juvela, M., Keihanen, E., Keskitalo, R., Kisner, T. S., Kneissl, R., Knoche, J., Knox, L., Kunz, M., Kurki-Suonio, H., Lagache, G., Lahteenmaki, A., Lamarre, J. -M., Lasenby, A., Lattanzi, M., Lawrence, C. R., Leahy, J. P., Leonardi, R., Lesgourgues, J., Levrier, F., Lewis, A., Liguori, M., Lilje, P. B., Linden-Vornle, M., Lopez-Caniego, M., Lubin, P. M., Macias-Perez, J. F., Maggio, G., Maino, D., Mandolesi, N., Mangilli, A., Marchini, A., Martin, P. G., Martinelli, M., Martinez-Gonzalez, E., Masi, S., Matarrese, S., Mazzotta, P., McGehee, P., Meinhold, P. R., Melchiorri, A., Melin, J. -B., Mendes, L., Mennella, A., Migliaccio, M., Millea, M., Mitra, S., Miville-Deschenes, M. -A., Moneti, A., Montier, L., Morgante, G., Mortlock, D., Moss, A., Munshi, D., Murphy, J. A., Naselsky, P., Nati, F., Natoli, P., Netterfield, C. B., Norgaard-Nielsen, H. U., Noviello, F., Novikov, D., Novikov, I., Oxborrow, C. A., Paci, F., Pagano, L., Pajot, F., Paladini, R., Paoletti, D., Partridge, B., Pasian, F., Patanchon, G., Pearson, T. J., Perdereau, O., Perotto, L., Perrotta, F., Pettorino, V., Piacentini, F., Piat, M., Pierpaoli, E., Pietrobon, D., Plaszczynski, S., Pointecouteau, E., Polenta, G., Popa, L., Pratt, G. W., Prezeau, G., Prunet, S., Puget, J. -L., Rachen, J. P., Reach, W. T., Rebolo, R., Reinecke, M., Remazeilles, M., Renault, C., Renzi, A., Ristorcelli, I., Rocha, G., Rosset, C., Rossetti, M., Roudier, G., d'Orfeuil, B. Rouille, Rowan-Robinson, M., Rubino-Martin, J. A., Rusholme, B., Said, N., Salvatelli, V., Salvati, L., Sandri, M., Santos, D., Savelainen, M., Savini, G., Scott, D., Seiffert, M. D., Serra, P., Shellard, E. P. S., Spencer, L. D., Spinelli, M., Stolyarov, V., Stompor, R., Sudiwala, R., Sunyaev, R., Sutton, D., Suur-Uski, A. -S., Sygnet, J. -F., Tauber, J. A., Terenzi, L., Toffolatti, L., Tomasi, M., Tristram, M., Trombetti, T., Tucci, M., Tuovinen, J., Turler, M., Umana, G., Valenziano, L., Valiviita, J., Van Tent, B., Vielva, P., Villa, F., Wade, L. A., Wandelt, B. D., Wehus, I. K., White, M., White, S. D. M., Wilkinson, A., Yvon, D., Zacchei, A., and Zonca, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present results based on full-mission Planck observations of temperature and polarization anisotropies of the CMB. These data are consistent with the six-parameter inflationary LCDM cosmology. From the Planck temperature and lensing data, for this cosmology we find a Hubble constant, H0= (67.8 +/- 0.9) km/s/Mpc, a matter density parameter Omega_m = 0.308 +/- 0.012 and a scalar spectral index with n_s = 0.968 +/- 0.006. (We quote 68% errors on measured parameters and 95% limits on other parameters.) Combined with Planck temperature and lensing data, Planck LFI polarization measurements lead to a reionization optical depth of tau = 0.066 +/- 0.016. Combining Planck with other astrophysical data we find N_ eff = 3.15 +/- 0.23 for the effective number of relativistic degrees of freedom and the sum of neutrino masses is constrained to < 0.23 eV. Spatial curvature is found to be |Omega_K| < 0.005. For LCDM we find a limit on the tensor-to-scalar ratio of r <0.11 consistent with the B-mode constraints from an analysis of BICEP2, Keck Array, and Planck (BKP) data. Adding the BKP data leads to a tighter constraint of r < 0.09. We find no evidence for isocurvature perturbations or cosmic defects. The equation of state of dark energy is constrained to w = -1.006 +/- 0.045. Standard big bang nucleosynthesis predictions for the Planck LCDM cosmology are in excellent agreement with observations. We investigate annihilating dark matter and deviations from standard recombination, finding no evidence for new physics. The Planck results for base LCDM are in agreement with BAO data and with the JLA SNe sample. However the amplitude of the fluctuations is found to be higher than inferred from rich cluster counts and weak gravitational lensing. Apart from these tensions, the base LCDM cosmology provides an excellent description of the Planck CMB observations and many other astrophysical data sets., Comment: Abstract severely abridged. Revised to match version accepted by Astronomy & Astrophysics. Many minor changes, but basic results remain unchanged
Published: 2015
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30. Radio-Gamma-ray connection and spectral evolution in 4C +49.22 (S4 1150+49): the Fermi, Swift and Planck view

Author: Cutini, S., Ciprini, S., Orienti, M., Tramacere, A., D'Ammando, F., Verrecchia, F., Polenta, G., Carrasco, L., D'Elia, V., Giommi, P., Gonzalez-Nuevo, J., Grandi, P., Harrison, D., Hays, E., Hoversten, E., Larsson, S., Lahteenmaki, A., Leon-Tavares, J., Lopez-Caniego, M., Natoli, P., Ojha, R., Partridge, B., Porras, A., Reyes, L., Recillas, E., and Torresi, E.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The Large Area Telescope on board the Fermi Gamma-ray Space Telescope detected a strong gamma-ray flare on 2011 May 15 from a source identified as 4C 49.22, a flat spectrum radio quasar also known as S4 1150+49. This blazar, characterised by a prominent radio-optical-X-ray jet, was in a low gamma-ray activity state during the first years of Fermi observations. Simultaneous observations during the quiescent, outburst and post-flare gamma-ray states were obtained by Swift, Planck and optical-IR-radio telescopes (INAOE, Catalina CSS, VLBA, Metsahovi). The flare is observed from microwave to X-ray bands with correlated variability and the Fermi, Swift and Planck data for this FSRQ show some features more typical of BL Lac objects, like the synchrotron peak in the optical band that outshines the thermal blue-bump emission, and the X-ray spectral softening. Multi-epoch VLBA observations show the ejection of a new component close in time with the GeV gamma-ray flare. The radio-to-gamma-ray spectral energy distribution is modeled and fitted successfully for the outburst and the post-flare epochs using either a single flaring blob with two emission processes (synchrotron self Compton, and external-radiation Compton), and a two-zone model with SSC-only mechanism., Comment: 20 pages, 12 figures and 12 tables and accepted by MNRAS
Published: 2014
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31. Parents' perception of treatment-related toxicity in children treated according to the NOPHO ALL2008 protocol for acute lymphoblastic leukemia

Author: Mogensen, Nina, Kreicbergs, Ulrika, Albertsen, Birgitte K., Lahteenmaki, Paivi M., Heyman, Mats, Harila, Arja, Mogensen, Nina, Kreicbergs, Ulrika, Albertsen, Birgitte K., Lahteenmaki, Paivi M., Heyman, Mats, and Harila, Arja
Abstract: This study aimed to assess how parents perceived treatment-related side effects during acute lymphoblastic leukemia (ALL) treatment. Parents of children 1-17.9 years at diagnosis in Sweden, Finland, and Denmark who were alive and in first remission >= 6 months after end of ALL treatment were asked to respond on specific items regarding how their child was affected by side effects related to vincristine (VCR), corticosteroids, peg-asparaginase (ASP), and maintenance therapy, as well as overall impact of these treatments, complications in general, and their perception of impact on their child in comparison with other children with ALL. Parents of 307 children responded. More than a third reported that their child had been affected to a high extent by VCR (39.7%) and corticosteroids (35.8%), with walking difficulties, muscular weakness, pain, changes in appetite, and mood swings as the most common and severe symptoms. Reporting of these toxicities was lacking from the NOPHO ALL2008 database, except for peripheral paralysis (12.1%). For distinct toxicities reported in the NOPHO ALL2008 database, for example, thrombosis and pancreatitis, parent reports were similar to the database. Although a high overall negative impact during treatment was reported, parents generally rated the impact on their child as less, or similar, to other children with ALL. Parents perceived VCR and corticosteroid therapy, in particular, to have a negative impact on their child during ALL treatment, which was not captured in the NOPHO ALL2008 toxicity reporting. Our results highlight the importance of including patient/parent-reported outcomes in toxicity reporting.
Published: 2024
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32. Radiotherapy-induced vascular cognitive impairment 20 years after childhood brain tumor

Author: Remes, Tiina Maria, Suo-Palosaari, Maria Helena, Arikoski, Pekka Matti, Harila, Marika, Koskenkorva, Paeivi Katri Tuulikki, Lahteenmaki, Paivi Maria, Lonnqvist, Tuula Riitta Irmeli, Ojaniemi, Marja Katariina, Pohjasniemi, Heli, Puosi, Riina, Ritari, Niina, Sirkia, Kirsti Helena, Sutela, Anna Kaarina, Toiviainen-Salo, Sanna-Maria, Rantala, Heikki Markku Johannes, Harila, Arja, Remes, Tiina Maria, Suo-Palosaari, Maria Helena, Arikoski, Pekka Matti, Harila, Marika, Koskenkorva, Paeivi Katri Tuulikki, Lahteenmaki, Paivi Maria, Lonnqvist, Tuula Riitta Irmeli, Ojaniemi, Marja Katariina, Pohjasniemi, Heli, Puosi, Riina, Ritari, Niina, Sirkia, Kirsti Helena, Sutela, Anna Kaarina, Toiviainen-Salo, Sanna-Maria, Rantala, Heikki Markku Johannes, and Harila, Arja
Abstract: Background: Studies have established that radiotherapy for childhood brain tumors (BTs) increases the risk of cerebrovascular disease (CVD); however, it is unclear how this will affect cognitive function. This study aimed to investigate the associations between radiotherapy-induced CVD, white matter hyperintensities (WMHs), and neurocognitive outcomes in adult survivors of childhood BTs. Methods: In a cross-sectional setting, we conducted a national cohort that included 68 radiotherapy-treated survivors of childhood BTs after a median follow-up of 20 years. Markers of CVD and WMHs were evaluated using brain MRI, and the sum of CVD-related findings was calculated. Additionally, the associations among CVD findings, WMHs, and neuropsychological test results were analyzed. Results: Of the 68 childhood BT survivors, 54 (79%) were diagnosed with CVD and/or WMHs at a median age of 27 years. CVD and/or WMHs were associated with lower scores for verbal intelligence quotient, performance intelligence quotient (PIQ), executive function, memory, and visuospatial ability (P < .05). Additionally, survivors with microbleeds had greater impairments in the PIQ, processing speed, executive function, and visuospatial ability (P < .05). WMHs and CVD burden were associated with greater difficulties in memory function and visuospatial ability (P < .05). Small-vessel disease burden was associated with PIQ scores, processing speed, working memory, and visuospatial ability. Conclusions: The study results suggest that markers of radiotherapy-induced CVD, the additive effect of CVD markers, and risk factors of dementia are associated with cognitive impairment, which may suggest that the survivors are at a high risk of developing early-onset dementia.
Published: 2024
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33. Multifrequency Studies of the Peculiar Quasar 4C +21.35 During the 2010 Flaring Activity

Author: Ackermann, M., Ajello, M., Allafort, A., Antolini, E., Barbiellini, G., Bastieri, D., Bellazzini, R., Bissaldi, E., Bonamente, E., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cavazzuti, E., Cecchi, C., Chaves, R. C. G., Chekhtman, A., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., D'Ammando, F., de Palma, F., Dermer, C. D., Silva, E. do Couto e, Donato, D., Drell, P. S., Favuzzi, C., Finke, J., Focke, W. B., Franckowiak, A., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Giglietto, N., Giordano, F., Giroletti, M., Godfrey, G., Grenier, I. A., Guiriec, S., Hayashida, M., Hewitt, J. W., Horan, D., Hughes, R. E., Iafrate, G., Johnson, A. S., Knodlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Mayer, M., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nemmen, R., Nuss, E., Ohsugi, T., Orienti, M., Orlando, E., Perkins, J. S., Pesce-Rollins, M., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Razzano, M., Reimer, A., Reimer, O., Sanchez, D. A., Schulz, A., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Stawarz, L., Takahashi, H., Takahashi, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Werner, M., Winer, B. L., Wood, D. L., Wood, K. S., Aleksic, J., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Bangale, P., de Almeida, U. Barres, Barrio, J. A., Gonzalez, J. Becerra, Bednarek, W., Berger, K., Bernardini, E., Biland, A., Blanch, O., Bock, R. K., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Fidalgo, D. Carreto, Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Caneva, G., De Lotto, B., Mendez, C. Delgado, Doert, M., Dominguez, A., Prester, D. Dominis, Dorner, D., Doro, M., Einecke, S., Eisenacher, D., Elsaesser, D., Farina, E., Ferenc, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Lopez, R. J. Garcia, Garczarczyk, M., Terrats, D. Garrido, Gaug, M., Giavitto, G., Godinovic, N., Munoz, A. Gonzalez, Gozzini, S. R., Hadasch, D., Herrero, A., Hildebrand, D., Hose, J., Hrupec, D., Idec, W., Kadenius, V., Kellermann, H., Knoetig, M. L., Kodani, K., Konno, Y., Krause, J., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lewandowska, N., Lindfors, E., Lombardi, S., Lopez, M., Lopez-Coto, R., Lopez-Oramas, A., Lorenz, E., Lozano, I., Makariev, M., Mallot, K., Maneva, G., Mankuzhiyil, N., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martinez, M., Mazin, D., Menzel, U., Meucci, M., Miranda, J. M., Mirzoyan, R., Moralejo, A., Munar-Adrover, P., Nakajima, D., Niedzwiecki, A., Nishijima, K., Nilsson, K., Nowak, N., Orito, R., Overkemping, A., Paiano, S., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes-Fortuny, X., Partini, S., Persic, M., Prada, F., Moroni, P. G. Prada, Prandini, E., Preziuso, S., Puljak, I., Reinthal, R., Rhode, W., Ribo, M., Rico, J., Garcia, J. Rodriguez, Rugamer, S., Saggion, A., Saito, T., Saito, K., Salvati, M., Satalecka, K., Scalzotto, V., Scapin, V., Schultz, C., Schweizer, T., Shore, S. N., Sillanpaa, A., Sitarek, J., Snidaric, I., Sobczynska, D., Spanier, F., Stamatescu, V., Stamerra, A., Steinbring, T., Storz, J., Sun, S., Suric, T., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzic, T., Tescaro, D., Teshima, M., Thaele, J., Tibolla, O., Toyama, T., Treves, A., Vogler, P., Wagner, R. M., Zandanel, F., Zanin, R., Aller, M. F., Angelakis, E., Blinov, D. A., Djorgovski, S. G., Drake, A. J., Efimova, N. V., Gurwell, M. A., Homan, D. C., Jordan, B., Kopatskaya, E. N., Kovalev, Y. Y., Kurtanidze, O. M., Lahteenmaki, A., Larionov, V. M., Lister, M. L., Nieppola, E., Nikolashvili, M. G., Ros, E., Savolainen, T., Sigua, L. A., and Tornikoski, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - Astrophysics of Galaxies
Abstract: The discovery of rapidly variable Very High Energy (VHE; E > 100 GeV) gamma-ray emission from 4C +21.35 (PKS 1222+216) by MAGIC on 2010 June 17, triggered by the high activity detected by the Fermi Large Area Telescope (LAT) in high energy (HE; E > 100 MeV) gamma-rays, poses intriguing questions on the location of the gamma-ray emitting region in this flat spectrum radio quasar. We present multifrequency data of 4C +21.35 collected from centimeter to VHE during 2010 to investigate the properties of this source and discuss a possible emission model. The first hint of detection at VHE was observed by MAGIC on 2010 May 3, soon after a gamma-ray flare detected by Fermi-LAT that peaked on April 29. The same emission mechanism may therefore be responsible for both the HE and VHE emission during the 2010 flaring episodes. Two optical peaks were detected on 2010 April 20 and June 30, close in time but not simultaneous with the two gamma-ray peaks, while no clear connection was observed between the X-ray an gamma-ray emission. An increasing flux density was observed in radio and mm bands from the beginning of 2009, in accordance with the increasing gamma-ray activity observed by Fermi-LAT, and peaking on 2011 January 27 in the mm regime (230 GHz). We model the spectral energy distributions (SEDs) of 4C +21.35 for the two periods of the VHE detection and a quiescent state, using a one-zone model with the emission coming from a very compact region outside the broad line region. The three SEDs can be fit with a combination of synchrotron self-Compton and external Compton emission of seed photons from a dust torus, changing only the electron distribution parameters between the epochs. The fit of the optical/UV part of the spectrum for 2010 April 29 seems to favor an inner disk radius of <6 gravitational radii, as one would expect from a prograde-rotating Kerr black hole., Comment: 46 pages, 10 figures, 4 tables. The Astrophysical Journal, Volume 786, Issue 2, article id. 157, 17 pp. Contact Authors: Filippo D'Ammando, Justin Finke, Davide Donato, Josefa Becerra Gonzalez, Tomislav Terzic. Figure 1 updated
Published: 2014
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34. The core shift effect in the blazar 3C 454.3

Author: Kutkin, A. M., Sokolovsky, K. V., Lisakov, M. M., Kovalev, Y. Y., Savolainen, T., Voytsik, P. A., Lobanov, A. P., Aller, H. D., Aller, M. F., Lahteenmaki, A., Tornikoski, M., Volvach, A. E., and Volvach, L. N.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Opacity-driven shifts of the apparent VLBI core position with frequency (the "core shift" effect) probe physical conditions in the innermost parts of jets in active galactic nuclei. We present the first detailed investigation of this effect in the brightest gamma-ray blazar 3C454.3 using direct measurements from simultaneous 4.6-43 GHz VLBA observations, and a time lag analysis of 4.8-37 GHz lightcurves from the UMRAO, CrAO, and Metsahovi observations in 2007-2009. The results support the standard Konigl model of jet physics in the VLBI core region. The distance of the core from the jet origin r_c(nu), the core size W(nu), and the lightcurve time lag DT(nu) all depend on the observing frequency nu as r_c(nu)~W(nu)~ DT(nu)~nu^-1/k. The obtained range of k=0.6-0.8 is consistent with the synchrotron self-absorption being the dominating opacity mechanism in the jet. The similar frequency dependence of r_c(nu) and W(nu) suggests that the external pressure gradient does not dictate the jet geometry in the cm-band core region. Assuming equipartition, the magnetic field strength scales with distance r as B = 0.4(r/1pc)^-0.8 G. The total kinetic power of electron/positron jet is about 10^44 ergs/s., Comment: Accepted for publication in MNRAS; 10 pages, 6 figures
Published: 2013
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35. Planck intermediate results. XIII. Constraints on peculiar velocities

Author: Planck Collaboration, Ade, P. A. R., Aghanim, N., Arnaud, M., Ashdown, M., Aumont, J., Baccigalupi, C., Balbi, A., Banday, A. J., Barreiro, R. B., Battaner, E., Benabed, K., Benoit-Levy, A., Bernard, J. -P., Bersanelli, M., Bielewicz, P., Bikmaev, I., Bobin, J., Bock, J. J., Bonaldi, A., Bond, J. R., Borrill, J., Bouchet, F. R., Burigana, C., Butler, R. C., Cabella, P., Cardoso, J. -F., Catalano, A., Chamballu, A., Chiang, L. -Y, Chon, G., Christensen, P. R., Clements, D. L., Colombi, S., Colombo, L. P. L., Crill, B. P., Cuttaia, F., Da Silva, A., Dahle, H., Davies, R. D., Davis, R. J., de Bernardis, P., de Gasperis, G., de Zotti, G., Delabrouille, J., Democles, J., Diego, J. M., Dolag, K., Dole, H., Donzelli, S., Dore, O., Doerl, U., Douspis, M., Dupac, X., Ensslin, T. A., Finelli, F., Flores-Cacho, I., Forni, O., Frailis, M., Frommert, M., Galeotta, S., Ganga, K., Genova-Santos, R. T., Giard, M., Giardino, G., Gonzalez-Nuevo, J., Gregorio, A., Gruppuso, A., Hansen, F. K., Harrison, D., Hernandez-Monteagudo, C., Herranz, D., Hildebrandt, S. R., Hivon, E., Holmes, W. A., Hovest, W., Huffenberger, K. M., Hurier, G., Jaffe, T. R., Jaffe, A. H., Jasche, J., Jones, W. C., Juvela, M., Keihanen, E., Keskitalo, R., Khamitov, I., Kisner, T. S., Knoche, J., Kunz, M., Kurki-Suonio, H., Lagache, G., Lahteenmaki, A., Lamarre, J. -M., Lasenby, A., Lawrence, C. R., Jeune, M. Le, Leonardi, R., Lilje, P. B., Linden-Vornle, M., Lopez-Caniego, M., Macias-Perez, J. F., Maino, D., Mak, D. S. Y., Mandolesi, N., Maris, M., Marleau, F., Martinez-Gonzalez, E., Masi, S., Matarrese, S., Mazzotta, P., Melchiorri, A., Melin, J. -B., Mendes, L., Mennella, A., Migliaccio, M., Mitra, S., Miville-Deschenes, M. -A., Moneti, A., Montier, L., Morgante, G., Mortlock, D., Moss, A., Munshi, D., Murphy, J. A., Naselsky, P., Nati, F., Natoli, P., Netterfield, C. B., Norgaard-Nielsen, H. U., Noviello, F., Novikov, D., Novikov, I., Osborne, S., Pagano, L., Paoletti, D., Perdereau, O., Perrotta, F., Piacentini, F., Piat, M., Pierpaoli, E., Pietrobon, D., Plaszczynski, S., Pointecouteau, E., Polenta, G., Popa, L., Poutanen, T., Pratt, G. W., Prunet, S., Puget, J. -L., Puisieux, S., Rachen, J. P., Rebolo, R., Reinecke, M., Remazeilles, M., Renault, C., Ricciardi, S., Roman, M., Rubino-Martin, J. A., Rusholme, B., Sandri, M., Savini, G., Scott, D., Spencer, L., Sunyaev, R., Sutton, D., Suur-Uski, A. -S., Sygnet, J. -F., Tauber, J. A., Terenzi, L., Toffolatti, L., Tomasi, M., Tristram, M., Tucci, M., Valenziano, L., Valiviita, J., Van Tent, B., Vielva, P., Villa, F., Vittorio, N., Wade, L. A., Welikala, N., Yvon, D., Zacchei, A., Zibin, J. P., and Zonca, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Using \Planck\ data combined with the Meta Catalogue of X-ray detected Clusters of galaxies (MCXC), we address the study of peculiar motions by searching for evidence of the kinetic Sunyaev-Zeldovich effect (kSZ). By implementing various filters designed to extract the kSZ generated at the positions of the clusters, we obtain consistent constraints on the radial peculiar velocity average, root mean square (rms), and local bulk flow amplitude at different depths. For the whole cluster sample of average redshift 0.18, the measured average radial peculiar velocity with respect to the cosmic microwave background (CMB) radiation at that redshift, i.e., the kSZ monopole, amounts to $72 \pm 60$ km s$^{-1}$. This constitutes less than 1% of the relative Hubble velocity of the cluster sample with respect to our local CMB frame. While the linear $\Lambda$CDM prediction for the typical cluster radial velocity rms at $z=0.15$ is close to 230km s$^{-1}$, the upper limit imposed by \Planck\ data on the cluster subsample corresponds to 800 km s$^{-1}$ at 95% confidence level, i.e., about three times higher. \Planck\ data also set strong constraints on the local bulk flow in volumes centred on the Local Group. There is no detection of bulk flow as measured in any comoving sphere extending to the maximum redshift covered by the cluster sample. A blind search for bulk flows in this sample has an upper limit of 254 km s$^{-1}$ (95% confidence level) dominated by CMB confusion and instrumental noise, indicating that the Universe is largely homogeneous on Gpc scales. In this context, in conjunction with supernova observations, \Planck\ is able to rule out a large class of inhomogeneous void models as alternatives to dark energy or modified gravity. The \Planck\ constraints on peculiar velocities and bulk flows are thus consistent with the $\Lambda$CDM scenario., Comment: 23 pages (including affiliations), 14 figures, minor changes, matches accepted version in A&A
Published: 2013
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36. Planck 2013 results. XXI. All-sky Compton parameter power spectrum and high-order statistics

Author: Planck Collaboration, Ade, P. A. R., Aghanim, N., Armitage-Caplan, C., Arnaud, M., Ashdown, M., Atrio-Barandela, F., Aumont, J., Baccigalupi, C., Banday, A. J., Barreiro, R. B., Bartlett, J. G., Battaner, E., Benabed, K., Benoit, A., Benoit-Levy, A., Bernard, J. -P., Bersanelli, M., Bielewicz, P., Bobin, J., Bock, J. J., Bonaldi, A., Bond, J. R., Borrill, J., Bouchet, F. R., Bridges, M., Bucher, M., Burigana, C., Butler, R. C., Cardoso, J. -F., Carvalho, P., Catalano, A., Challinor, A., Chamballu, A., Chiang, L. -Y, Chiang, H. C., Christensen, P. R., Church, S., Clements, D. L., Colombi, S., Colombo, L. P. L., Comis, B., Couchot, F., Coulais, A., Crill, B. P., Curto, A., Cuttaia, F., Da Silva, A., Danese, L., Davies, R. D., Davis, R. J., de Bernardis, P., de Rosa, A., de Zotti, G., Delabrouille, J., Delouis, J. -M., Desert, F. -X., Dickinson, C., Diego, J. M., Dolag, K., Dole, H., Donzelli, S., Dore, O., Douspis, M., Dupac, X., Efstathiou, G., Enblin, T. A., Eriksen, H. K., Finelli, F., Flores-Cacho, I., Forni, O., Frailis, M., Franceschi, E., Galeotta, S., Ganga, K., Genova-Santos, R. T., Giard, M., Giardino, G., Giraud-Heraud, Y., Gonzalez-Nuevo, J., Gorski, K. M., Gratton, S., Gregorio, A., Gruppuso, A., Hansen, F. K., Hanson, D., Harrison, D., Henrot-Versille, S., Hernandez-Monteagudo, C., Herranz, D., Hildebrandt, S. R., Hivon, E., Hobson, M., Holmes, W. A., Hornstrup, A., Hovest, W., Huffenberger, K. M., Hurier, G., Jaffe, T. R., Jaffe, A. H., Jones, W. C., Juvela, M., Keihanen, E., Keskitalo, R., Kisner, T. S., Kneissl, R., Knoche, J., Knox, L., Kunz, M., Kurki-Suonio, H., Lacasa, F., Lagache, G., Lahteenmaki, A., Lamarre, J. -M., Lasenby, A., Laureijs, R. J., Lawrence, C. R., Leahy, J. P., Leonardi, R., León-Tavares, J., Lesgourgues, J., Liguori, M., Lilje, P. B., Linden-Vornle, M., López-Caniego, M., Lubin, P. M., Macias-Perez, J. F., Maffei, B., Maino, D., Mandolesi, N., Marcos-Caballero, A., Maris, M., Marshall, D. J., Martin, P. G., Martinez-Gonzalez, E., Masi, S., Matarrese, S., Matthai, F., Mazzotta, P., Melchiorri, A., Melin, J. -B., Mendes, L., Mennella, A., Migliaccio, M., Mitra, S., Miville-Deschenes, M. -A., Moneti, A., Montier, L., Morgante, G., Mortlock, D., Moss, A., Munshi, D., Naselsky, P., Nati, F., Natoli, P., Netterfield, C. B., Norgaard-Nielsen, H. U., Noviello, F., Novikov, D., Novikov, I., Osborne, S., Oxborrow, C. A., Paci, F., Pagano, L., Pajot, F., Paoletti, D., Partridge, B., Pasian, F., Patanchon, G., Perdereau, O., Perotto, L., Perrotta, F., Piacentini, F., Piat, M., Pierpaoli, E., Pietrobon, D., Plaszczynski, S., Pointecouteau, E., Polenta, G., Ponthieu, N., Popa, L., Poutanen, T., Pratt, G. W., Prezeau, G., Prunet, S., Puget, J. -L., Rachen, J. P., Rebolo, R., Reinecke, M., Remazeilles, M., Renault, C., Ricciardi, S., Riller, T., Ristorcelli, I., Rocha, G., Rosset, C., Rossetti, M., Roudier, G., Rubino-Martin, J. A., Rusholme, B., Sandri, M., Santos, D., Savini, G., Scott, D., Seiffert, M. D., Shellard, E. P. S., Spencer, L. D., Starck, J. -L., Stolyarov, V., Stompor, R., Sudiwala, R., Sunyaev, R., Sureau, F., Sutton, D., Suur-Uski, A. -S., Sygnet, J. -F., Tauber, J. A., Tavagnacco, D., Terenzi, L., Toffolatti, L., Tomasi, M., Tristram, M., Tucci, M., Tuovinen, J., Umana, G., Valenziano, L., Valiviita, J., Van Tent, B., Varis, J., Vielva, P., Villa, F., Vittorio, N., Wade, L. A., Wandelt, B. D., White, S. D. M., Yvon, D., Zacchei, A., and Zonca, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We have constructed the first all-sky map of the thermal Sunyaev-Zeldovich (tSZ) effect by applying specifically tailored component separation algorithms to the 100 to 857 GHz frequency channel maps from the Planck survey. These maps show an obvious galaxy cluster tSZ signal that is well matched with blindly detected clusters in the Planck SZ catalogue. To characterize the signal in the tSZ map we have computed its angular power spectrum. At large angular scales ($\ell < 60$), the major foreground contaminant is the diffuse thermal dust emission. At small angular scales ($\ell > 500$) the clustered Cosmic Infrared Background (CIB) and residual point sources are the major contaminants. These foregrounds are carefully modelled and subtracted. We measure the tSZ power spectrum in angular scales, $0.17^{\circ} \lesssim \theta \lesssim 3.0^{\circ}$, that were previously unexplored. The measured tSZ power spectrum is consistent with that expected from the Planck catalogue of SZ sources, with additional clear evidence of signal from unresolved clusters and, potentially, diffuse warm baryons. We use the tSZ power spectrum to obtain the following cosmological constraints: $\sigma_8(\Omega_{\mathrm{m}}/0.28)^{3.2/8.1}=0.784 \pm 0.016 (68% C.L.). Marginalized band-powers of the Planck tSZ power spectrum and the best-fit model are given. The non-Gaussianity of the Compton parameter map is further characterized by computing its 1D probability distribution function and its bispectrum. These are used to place additional independent constraints on $\sigma_{8}$., Comment: 18 pages, 16 figures
Published: 2013
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37. Planck 2013 results. XIII. Galactic CO emission

Author: Planck Collaboration, Ade, P. A. R., Aghanim, N., Alves, M. I. R., Armitage-Caplan, C., Arnaud, M., Ashdown, M., Atrio-Barandela, F., Aumont, J., Baccigaluppi, C., Banday, A. J., Barreiro, R. B., Bartlett, J. G., Battaner, E., Benabed, K., Benoit, A., Benoit-Levy, A., Bernard, J. -P., Bersanelli, M., Bielewicz, P., Bobin, J., Bock, J. J., Bonaldi, A., Bond, J. R., Borrill, J., Bouchet, F. R., Boulanger, F., Bridges, M., Bucher, M., Burigana, C., Butler, R. C., Cardoso, J. -F., Catalano, A., Chamballu, A., Chary, R. -R., Chen, X., Chiang, L. -Y, Chiang, H. C., Christensen, P. R., Church, S., Clements, D. L., Colombi, S., Colombo, L. P. L., Combet, C., Couchot, F., Coulais, A., Crill, B. P., Curto, A., Cuttaia, F., Danese, L., Davies, R. D., de Bernardis, P., de Rosa, A., de Zotti, G., Delabrouille, J., Delouis, J. -M., Dempsey, J. T., Desert, F. -X., Dickinson, C., Diego, J. M., Dole, H., Donzelli, S., Dore, O., Douspis, M., Dupac, X., Efstathiou, G., Enblin, T. A., Eriksen, H. K., Falgarone, E., Finelli, F., Forni, O., Frailis, M., Franceschi, E., Fukui, Y., Galeotta, S., Ganga, K., Giard, M., Giraud-Heraud, Y., Gonzalez-Nuevo, J., Gorski, K. M., Gratton, S., Gregorio, A., Gruppuso, A., Handa, T., Hansen, F. K., Hanson, D., Harrison, D., Henrot-Versille, S., Hernandez-Monteagudo, C., Herranz, D., Hildebrandt, S. R., Hily-Blant, P., Hivon, E., Hobson, M., Holmes, W. A., Hornstrup, A., Hovest, W., Huffenberger, K. M., Hurier, G., Jaffe, T. R., Jaffe, A. H., Jewell, J., Jones, W. C., Juvela, M., Keihanen, E., Keskitalo, R., Kisner, T. S., Knoche, J., Knox, L., Kunz, M., Kurki-Suonio, H., Lagache, G., Lahteenmaki, A., Lamarre, J. -M., Lasenby, A., Laureijs, R. J., Lawrence, C. R., Leonardi, R., Leon-Tavares, J., Lesgourgues, J., Liguori, M., Lilje, P. B., Linden-Vornle, M., Lopez-Caniego, M., Lubin, P. M., Macias-Perez, J. F., Maffei, B., Mandolesi, N., Maris, M., Marshall, D. J., Martin, P. G., Martinez-Gonzalez, E., Masi, S., Matarrese, S., Matthai, F., Mazzotta, P., McGehee, P., Melchiorri, A., Mendes, L., Mennella, A., Migliaccio, M., Mitra, S., Miville-Deschenes, M. -A., Moneti, A., Montier, L., Moore, T. J. T., Morgante, G., Morino, J., Mortlock, D., Munshi, D., Nakajima, T., Naselsky, P., Nati, F., Natoli, P., Netterfield, C. B., Norgaard-Nielsen, H. U., Noviello, F., Novikov, D., Novikov, I., Okuda, T., Osborne, S., Oxborrow, C. A., Paci, F., Pagano, L., Pajot, F., Paladini, R., Paoletti, D., Pasian, F., Patanchon, G., Perdereau, O., Perotto, L., Perrotta, F., Piacentini, F., Piat, M., Pierpaoli, E., Pietrobon, D., Plaszczynski, S., Pointecouteau, E., Polenta, G., Ponthieu, N., Popa, L., Poutanen, T., Pratt, G. W., Preezeau, G., Prunet, S., Puget, J. -L., Rachen, J. P., Reach, W. T., Rebolo, R., Reinecke, M., Remazeilles, M., Renault, C., Ricciardi, S., Riller, T., Ristorcelli, I., Rocha, G., Rosset, C., Roudier, G., Rowan-Robinson, M., Rubino-Martin, J. A., Rusholme, B., Sandri, M., Santos, D., Savini, G., Scott, D., Seiffert, M. D., Shellard, E. P. S., Spencer, L. D., Starck, J. -L., Stolyarov, V., Stompor, R., Sudiwala, R., Sunyaev, R., Sureau, F., Sutton, D., Suur-Uski, A. -S., Sygnet, J. -F., Tauber, J. A., Tavagnacco, D., Terenzi, L., Thomas, H. S., Toffolatti, L., Tomasi, M., Torii, K., Tristram, M., Tucci, M., Tuovinen, J., Umana, G., Valenziano, L., Valiviita, J., Van Tent, B., Vielva, P., Villa, F., Vittorio, N., Wade, L. A., Wandelt, B. D., Wehus, I. K., Yoda, H. Yamamoto T., Yvon, D., Zacchei, A., and Zonca, A.
Subjects: Astrophysics - Astrophysics of Galaxies, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Rotational transition lines of CO play a major role in molecular radio astronomy and in particular in the study of star formation and the Galactic structure. Although a wealth of data exists in the Galactic plane and some well-known molecular clouds, there is no available CO high sensitivity all-sky survey to date. Such all-sky surveys can be constructed using the \Planck\ HFI data because the three lowest CO rotational transition lines at 115, 230 and 345 GHz significantly contribute to the signal of the 100, 217 and 353 GHz HFI channels respectively. Two different component separation methods are used to extract the CO maps from Planck HFI data. The maps obtained are then compared to one another and to existing external CO surveys. From these quality checks the best CO maps in terms of signal to noise and/or residual foreground contamination are selected. Three sets of velocity-integrated CO emission maps are produced: Type 1 maps of the CO (1-0), (2-1), and (3-2) rotational transitions with low foreground contamination but moderate signal-to-noise ratio; Type 2 maps for the (1-0) and (2-1) transitions with a better signal-to-noise ratio; and one Type 3 map, a line composite map with the best signal-to-noise ratio in order to locate the faintest molecular regions. The maps are described in detail. They are shown to be fully compatible with previous surveys of parts of the Galactic Plane and also of fainter regions out of the Galactic plane. The Planck HFI velocity-integrated CO maps for the (1-0), (2-1), and (3-2) rotational transitions provide an unprecedented all-sky CO view of the Galaxy. These maps are also of great interest to monitor potential CO contamination on CMB \Planck\ studies., Comment: 24 pages, 17 figures
Published: 2013
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38. Planck 2013 results. XV. CMB power spectra and likelihood

Author: Planck collaboration, Ade, P. A. R., Aghanim, N., Armitage-Caplan, C., Arnaud, M., Ashdown, M., Atrio-Barandela, F., Aumont, J., Baccigalupi, C., Banday, A. J., Barreiro, R. B., Bartlett, J. G., Battaner, E., Benabed, K., Benoit, A., Benoit-Levy, A., Bernard, J. -P., Bersanelli, M., Bielewicz, P., Bobin, J., Bock, J. J., Bonaldi, A., Bonavera, L., Bond, J. R., Borrill, J., Bouchet, F. R., Boulanger, F., Bridges, M., Bucher, M., Burigana, C., Butler, R. C., Calabrese, E., Cardoso, J. -F., Catalano, A., Challinor, A., Chamballu, A., Chiang, L. -Y, Chiang, H. C., Christensen, P. R., Church, S., Clements, D. L., Colombi, S., Colombo, L. P. L., Combet, C., Couchot, F., Coulais, A., Crill, B. P., Curto, A., Cuttaia, F., Danese, L., Davies, R. D., Davis, R. J., de Bernardis, P., de Rosa, A., de Zotti, G., Delabrouille, J., Delouis, J. -M., Desert, F. -X., Dickinson, C., Diego, J. M., Dole, H., Donzelli, S., Dore, O., Douspis, M., Dunkley, J., Dupac, X., Efstathiou, G., Elsner, F., Ensslin, T. A., Eriksen, H. K., Finelli, F., Forni, O., Frailis, M., Fraisse, A. A., Franceschi, E., Gaier, T. C., Galeotta, S., Galli, S., Ganga, K., Giard, M., Giardino, G., Giraud-Heraud, Y., Gjerlow, E., Gonzalez-Nuevo, J., Gorski, K. M., Gratton, S., Gregorio, A., Gruppuso, A., Gudmundsson, J. E., Hansen, F. K., Hanson, D., Harrison, D., Helou, G., Henrot-Versille, S., Hernandez-Monteagudo, C., Herranz, D., Hildebrandt, S. R., Hivon, E., Hobson, M., Holmes, W. A., Hornstrup, A., Hovest, W., Huffenberger, K. M., Hurier, G., Jaffe, T. R., Jaffe, A. H., Jewell, J., Jones, W. C., Juvela, M., Keihanen, E., Keskitalo, R., Kiiveri, K., Kisner, T. S., Kneissl, R., Knoche, J., Knox, L., Kunz, M., Kurki-Suonio, H., Lagache, G., Lahteenmaki, A., Lamarre, J. -M., Lasenby, A., Lattanzi, M., Laureijs, R. J., Lawrence, C. R., Jeune, M. Le, Leach, S., Leahy, J. P., Leonardi, R., Leon-Tavares, J., Lesgourgues, J., Liguori, M., Lilje, P. B., Lindholm, V., Linden-Vornle, M., Lopez-Caniego, M., Lubin, P. M., Macias-Perez, J. F., Maffei, B., Maino, D., Mandolesi, N., Marinucci, D., Maris, M., Marshall, D. J., Martin, P. G., Martinez-Gonzalez, E., Masi, S., Matarrese, S., Matthai, F., Mazzotta, P., Meinhold, P. R., Melchiorri, A., Mendes, L., Menegoni, E., Mennella, A., Migliaccio, M., Millea, M., Mitra, S., Miville-Deschenes, M. -A., Molinari, D., Moneti, A., Montier, L., Morgante, G., Mortlock, D., Moss, A., Munshi, D., Naselsky, P., Nati, F., Natoli, P., Netterfield, C. B., Norgaard-Nielsen, H. U., Noviello, F., Novikov, D., Novikov, I., O'Dwyer, I. J., Orieux, F., Osborne, S., Oxborrow, C. A., Paci, F., Pagano, L., Pajot, F., Paladini, R., Paoletti, D., Partridge, B., Pasian, F., Patanchon, G., Paykari, P., Perdereau, O., Perotto, L., Perrotta, F., Piacentini, F., Piat, M., Pierpaoli, E., Pietrobon, D., Plaszczynski, S., Pointecouteau, E., Polenta, G., Ponthieu, N., Popa, L., Poutanen, T., Pratt, G. W., Prezeau, G., Prunet, S., Puget, J. -L., Rachen, J. P., Rahlin, A., Rebolo, R., Reinecke, M., Remazeilles, M., Renault, C., Ricciardi, S., Riller, T., Ringeval, C., Ristorcelli, I., Rocha, G., Rosset, C., Roudier, G., Rowan-Robinson, M., Rubino-Martin, J. A., Rusholme, B., Sandri, M., Sanselme, L., Santos, D., Savini, G., Scott, D., Seiffert, M. D., Shellard, E. P. S., Spencer, L. D., Starck, J. -L., Stolyarov, V., Stompor, R., Sudiwala, R., Sureau, F., Sutton, D., Suur-Uski, A. -S., Sygnet, J. -F., Tauber, J. A., Tavagnacco, D., Terenzi, L., Toffolatti, L., Tomasi, M., Tristram, M., Tucci, M., Tuovinen, J., Turler, M., Valenziano, L., Valiviita, J., Van Tent, B., Varis, J., Vielva, P., Villa, F., Vittorio, N., Wade, L. A., Wandelt, B. D., Wehus, I. K., White, M., White, S. D. M., Yvon, D., Zacchei, A., and Zonca, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present the Planck likelihood, a complete statistical description of the two-point correlation function of the CMB temperature fluctuations. We use this likelihood to derive the Planck CMB power spectrum over three decades in l, covering 2 <= l <= 2500. The main source of error at l <= 1500 is cosmic variance. Uncertainties in small-scale foreground modelling and instrumental noise dominate the error budget at higher l's. For l < 50, our likelihood exploits all Planck frequency channels from 30 to 353 GHz through a physically motivated Bayesian component separation technique. At l >= 50, we employ a correlated Gaussian likelihood approximation based on angular cross-spectra derived from the 100, 143 and 217 GHz channels. We validate our likelihood through an extensive suite of consistency tests, and assess the impact of residual foreground and instrumental uncertainties on cosmological parameters. We find good internal agreement among the high-l cross-spectra with residuals of a few uK^2 at l <= 1000. We compare our results with foreground-cleaned CMB maps, and with cross-spectra derived from the 70 GHz Planck map, and find broad agreement in terms of spectrum residuals and cosmological parameters. The best-fit LCDM cosmology is in excellent agreement with preliminary Planck polarisation spectra. The standard LCDM cosmology is well constrained by Planck by l <= 1500. For example, we report a 5.4 sigma deviation from n_s /= 1. Considering various extensions beyond the standard model, we find no indication of significant departures from the LCDM framework. Finally, we report a tension between the best-fit LCDM model and the low-l spectrum in the form of a power deficit of 5-10% at l <~ 40, significant at 2.5-3 sigma. We do not elaborate further on its cosmological implications, but note that this is our most puzzling finding in an otherwise remarkably consistent dataset. (Abridged), Comment: This paper is one of a set associated with the 2013 release of data from the Planck mission. 62 pages, 64 figures, 12 tables
Published: 2013
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39. Planck 2013 results. XXII. Constraints on inflation

Author: Planck Collaboration, Ade, P. A. R., Aghanim, N., Armitage-Caplan, C., Arnaud, M., Ashdown, M., Atrio-Barandela, F., Aumont, J., Baccigalupi, C., Banday, A. J., Barreiro, R. B., Bartlett, J. G., Bartolo, N., Battaner, E., Benabed, K., Benoit, A., Benoit-Levy, A., Bernard, J. -P., Bersanelli, M., Bielewicz, P., Bobin, J., Bock, J. J., Bonaldi, A., Bond, J. R., Borrill, J., Bouchet, F. R., Bridges, M., Bucher, M., Burigana, C., Butler, R. C., Calabrese, E., Cardoso, J. -F., Catalano, A., Challinor, A., Chamballu, A., Chiang, H. C., Chiang, L. -Y, Christensen, P. R., Church, S., Clements, D. L., Colombi, S., Colombo, L. P. L., Couchot, F., Coulais, A., Crill, B. P., Curto, A., Cuttaia, F., Danese, L., Davies, R. D., Davis, R. J., de Bernardis, P., de Rosa, A., de Zotti, G., Delabrouille, J., Delouis, J. -M., Desert, F. -X., Dickinson, C., Diego, J. M., Dole, H., Donzelli, S., Dore, O., Douspis, M., Dunkley, J., Dupac, X., Efstathiou, G., Ensslin, T. A., Eriksen, H. K., Finelli, F., Forni, O., Frailis, M., Franceschi, E., Galeotta, S., Ganga, K., Gauthier, C., Giard, M., Giardino, G., Giraud-Hiraud, Y., Gonzalez-Nuevo, J., Gorski, K. M., Gratton, S., Gregorio, A., Gruppuso, A., Hamann, J., Hansen, F. K., Hanson, D., Harrison, D., Henrot-Versille, S., Hernandez-Monteagudo, C., Herranz, D., Hildebrandt, S. R., Hivon, E., Hobson, M., Holmes, W. A., Hornstrup, A., Hovest, W., Huffenberger, K. M., Jaffe, A. H., Jaffe, T. R., Jones, W. C., Juvela, M., Keihanen, E., Keskitalo, R., Kisner, T. S., Kneissl, R., Knoche, J., Knox, L., Kunz, M., Kurki-Suonio, H., Lagache, G., Lahteenmaki, A., Lamarre, J. -M., Lasenby, A., Laureijs, R. J., Lawrence, C. R., Leach, S., Leahy, J. P., Leonardi, R., Lesgourgues, J., Lewis, A., Liguori, M., Lilje, P. B., Linden-Vernle, M., Lopez-Caniego, M., Lubin, P. M., Macias-Perez, J. F., Maffei, B., Maino, D., Mandolesi, N., Maris, M., Marshall, D. J., Martin, P. G., Martinez-Gonzalez, E., Masi, S., Massardi, M., Matarrese, S., Matthai, F., Mazzotta, P., Meinhold, P. R., Melchiorri, A., Mendes, L., Mennella, A., Migliaccio, M., Mitra, S., Miville-Deschenes, M. -A., Moneti, A., Montier, L., Morgante, G., Mortlock, D., Moss, A., Munshi, D., Murphy, J. A., Naselsky, P., Nati, F., Natoli, P., Netterfield, C. B., Norgaard-Nielsen, H. U., Noviello, F., Novikov, D., Novikov, I., O'Dwyer, I. J., Osborne, S., Oxborrow, C. A., Paci, F., Pagano, L., Pajot, F., Paladini, R., Pandolfi, S., Paoletti, D., Partridge, B., Pasian, F., Patanchon, G., Peiris, H. V., Perdereau, O., Perotto, L., Perrotta, F., Piacentini, F., Piat, M., Pierpaoli, E., Pietrobon, D., Plaszczynski, S., Pointecouteau, E., Polenta, G., Ponthieu, N., Popa, L., Poutanen, T., Pratt, G. W., Prezeau, G., Prunet, S., Puget, J. -L., Rachen, J. P., Rebolo, R., Reinecke, M., Remazeilles, M., Renault, C., Ricciardi, S., Riller, T., Ristorcelli, I., Rocha, G., Rosset, C., Roudier, G., Rowan-Robinson, M., Rubino-Martin, J. A., Rusholme, B., Sandri, M., Santos, D., Savelainen, M., Savini, G., Scott, D., Seiffert, M. D., Shellard, E. P. S., Spencer, L. D., Starck, J. -L., Stolyarov, V., Stompor, R., Sudiwala, R., Sunyaev, R., Sureau, F., Sutton, D., Suur-Uski, A. -S., Sygnet, J. -F., Tauber, J. A., Tavagnacco, D., Terenzi, L., Toffolatti, L., Tomasi, M., Treguer-Goudineau, J., Tristram, M., Tucci, M., Tuovinen, J., Valenziano, L., Valiviita, J., Van Tent, B., Varis, J., Vielva, P., Villa, F., Vittorio, N., Wade, L. A., Wandelt, B. D., White, M., Wilkinson, A., Yvon, D., Zacchei, A., Zibin, J. P., and Zonca, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We analyse the implications of the Planck data for cosmic inflation. The Planck nominal mission temperature anisotropy measurements, combined with the WMAP large-angle polarization, constrain the scalar spectral index to $n_s = 0.9603 \pm 0.0073$, ruling out exact scale invariance at over 5 $\sigma$. Planck establishes an upper bound on the tensor-to-scalar ratio of r < 0.11 (95% CL). The Planck data thus shrink the space of allowed standard inflationary models, preferring potentials with V" < 0. Exponential potential models, the simplest hybrid inflationary models, and monomial potential models of degree n > 2 do not provide a good fit to the data. Planck does not find statistically significant running of the scalar spectral index, obtaining $d n_s/d ln k = -0.0134 \pm 0.0090$. Several analyses dropping the slow-roll approximation are carried out, including detailed model comparison and inflationary potential reconstruction. We also investigate whether the primordial power spectrum contains any features. We find that models with a parameterized oscillatory feature improve the fit $\chi^2$ by ~ 10; however, Bayesian evidence does not prefer these models. We constrain several single-field inflation models with generalized Lagrangians by combining power spectrum data with bounds on $f_\mathrm{NL}$ measured by Planck. The fractional primordial contribution of CDM isocurvature modes in the curvaton and axion scenarios has upper bounds of 0.25% or 3.9% (95% CL), respectively. In models with arbitrarily correlated CDM or neutrino isocurvature modes, an anticorrelation can improve $\chi^2$ by approximatively 4 as a result of slightly lowering the theoretical prediction for the $\ell<40$ multipoles relative to the higher multipoles. Nonetheless, the data are consistent with adiabatic initial conditions., Comment: 44 pages, 25 figures, 12 tables; updated version; small changes to match the published version
Published: 2013
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40. Locating the Gamma-ray Flaring Emission of Blazar AO 0235+164 in the Jet at Parsec Scales Through Multi Spectral Range Monitoring

Author: Agudo, Ivan, Marscher, Alan P., Jorstad, Svetlana G., Larionov, Valeri M., Gomez, Jose L., Lahteenmaki, Anne, Smith, Paul S., Nilsson, Kari, Readhead, Anthony C. S., Aller, Margo F., Heidt, Jochen, Gurwell, Mark, Thum, Clemens, Wehrle, Ann E., and Kurtanidze, Omar M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Extragalactic Astrophysics
Abstract: We present observations of a major outburst at centimeter, millimeter, optical, X-ray, and gamma-ray wavelengths of the BL Lacertae object AO 0235+164 in 2008. We analyze the timing of multi-waveband variations in the flux and linear polarization, as well as changes in Very Long Baseline Array (VLBA) images at 7mm with ~0.15 milliarcsecond resolution. The association of the events at different wavebands is confirmed at high statistical significance by probability arguments and Monte-Carlo simulations. A series of sharp peaks in optical linear polarization, as well as a pronounced maximum in the 7mm polarization of a superluminal jet knot, indicate rapid fluctuations in the degree of ordering of the magnetic field. These results lead us to conclude that the outburst occurred in the jet both in the quasi-stationary core and in the superluminal knot, both at >12 parsecs downstream of the supermassive black hole. We interpret the outburst as a consequence of the propagation of a disturbance, elongated along the line of sight by light-travel time delays, that passes through a standing recollimation shock in the core and propagates down the jet to create the superluminal knot. The multi-wavelength light curves vary together on long time-scales (months/years), but the correspondence is poorer on shorter time-scales. This, as well as the variability of the polarization and the dual location of the outburst, agrees with the expectations of a multi-zone emission model in which turbulence plays a major role in modulating the synchrotron and inverse Compton fluxes., Comment: 2012 Fermi Symposium proceedings - eConf C121028
Published: 2013

41. Basic properties of Narrow-Line Seyfert 1 Galaxies with Relativistic Jets

Author: Foschini, L., Angelakis, E., Bonnoli, G., Braito, V., Caccianiga, A., Fuhrmann, L., Gallo, L., Ghirlanda, G., Ghisellini, G., Grupe, D., Hamilton, T., Kaufmann, S., Komossa, S., Kovalev, Y. Y., Lahteenmaki, A., Lister, M. L., Mannheim, K., Maraschi, L., Mathur, S., Peterson, B. M., Romano, P., Severgnini, P., Tagliaferri, G., Tammi, J., Tavecchio, F., Tibolla, O., Tornikoski, M., and Vercellone, S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the preliminary results of a survey performed with Swift to observe a sample of radio-loud Narrow-Line Seyfert 1 Galaxies (RLNLS1s). Optical-to-X-ray data from Swift are complemented with gamma-ray observations from Fermi/LAT and radio measurements available in the literature. The comparison with a sample of bright Fermi blazars indicates that RLNLS1s seem to be the low-power tail of the distribution., Comment: 2 pages, 1 figure. Proceedings "X-ray Astronomy: the next 50 years" (Milano, 1-5 October 2012). To be published on Mem. SAIt. Errata-Corrige: found an error in the normalization of gamma-ray data. The old displayed values were luminosity densities (Lnu) instead of nuLnu. Now, the figures display the corrected values. Nothing changes in the concepts
Published: 2013

42. Rapid TeV Gamma-Ray Flaring of BL Lacertae

Author: Arlen, T., Aune, T., Beilicke, M., Benbow, W., Bouvier, A., Buckley, J. H., Bugaev, V., Cesarini, A., Ciupik, L., Connolly, M. P., Cui, W., Dickherber, R., Dumm, J., Errando, M., Falcone, A., Federici, S., Feng, Q., Finley, J. P., Finnegan, G., Fortson, L., Furniss, A., Galante, N., Gall, D., Griffin, S., Grube, J., Gyuk, G., Hanna, D., Holder, J., Humensky, T. B., Kaaret, P., Karlsson, N., Kertzman, M., Khassen, Y., Kieda, D., Krawczynski, H., Krennrich, F., Maier, G., Moriarty, P., Mukherjee, R., Nelson, T., de Bhroithe, A. O'Faolain, Ong, R. A., Orr, M., Park, N., Perkins, J. S., Pichel, A., Pohl, M., Prokoph, H., Quinn, J., Ragan, K., Reyes, L. C., Reynolds, P. T., Roache, E., Saxon, D. B., Schroedter, M., Sembroski, G. H., Staszak, D., Telezhinsky, I., Tesic, G., Theiling, M., Tsurusaki, K., Varlotta, A., Vincent, S., Wakely, S. P., Weekes, T. C., Weinstein, A., Welsing, R., Williams, D. A., Zitzer, B., Jorstad, S. G., MacDonald, N. R., Marscher, A. P., Smith, P. S., Walker, R. C., Hovatta, T., Richards, J., Max-Moerbeck, W., Readhead, A., Lister, M. L., Kovalev, Y. Y., Pushkarev, A. B., Gurwell, M. A., Lahteenmaki, A., Nieppola, E., Tornikoski, M., and Jarvela, E.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report on the detection of a very rapid TeV gamma-ray flare from BL Lacertae on 2011 June 28 with the Very Energetic Radiation Imaging Telescope Array System (VERITAS). The flaring activity was observed during a 34.6-minute exposure, when the integral flux above 200 GeV reached $(3.4\pm0.6) \times 10^{-6} \;\text{photons}\;\text{m}^{-2}\text{s}^{-1}$, roughly 125% of the Crab Nebula flux measured by VERITAS. The light curve indicates that the observations missed the rising phase of the flare but covered a significant portion of the decaying phase. The exponential decay time was determined to be $13\pm4$ minutes, making it one of the most rapid gamma-ray flares seen from a TeV blazar. The gamma-ray spectrum of BL Lacertae during the flare was soft, with a photon index of $3.6\pm 0.4$, which is in agreement with the measurement made previously by MAGIC in a lower flaring state. Contemporaneous radio observations of the source with the Very Long Baseline Array (VLBA) revealed the emergence of a new, superluminal component from the core around the time of the TeV gamma-ray flare, accompanied by changes in the optical polarization angle. Changes in flux also appear to have occurred at optical, UV, and GeV gamma-ray wavelengths at the time of the flare, although they are difficult to quantify precisely due to sparse coverage. A strong flare was seen at radio wavelengths roughly four months later, which might be related to the gamma-ray flaring activities. We discuss the implications of these multiwavelength results., Comment: Accepted for publication in The Astrophysical Journal
Published: 2012
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43. Radio-to-gamma-ray Monitoring of the Narrow-Line Seyfert 1 Galaxy PMN J0948+0022 from 2008 to 2011

Author: Foschini, L., Angelakis, E., Fuhrmann, L., Ghisellini, G., Hovatta, T., Lahteenmaki, A., Lister, M. L., Braito, V., Gallo, L., Hamilton, T. S., Kino, M., Komossa, S., Pushkarev, A. B., Thompson, D. J., Tibolla, O., Tramacere, A., Carraminana, A., Carrasco, L., Falcone, A., Giroletti, M., Grupe, D., Kovalev, Y. Y., Krichbaum, T. P., Max-Moerbeck, W., Nestoras, I., Pearson, T. J., Porras, A., Readhead, A. C. S., Recillas, E., Richards, J. L., Riquelme, D., Sievers, A., Tammi, J., Tornikoski, M., Ungerechts, H., Zensus, J. A., Celotti, A., Bonnoli, G., Doi, A., Maraschi, L., Tagliaferri, G., and Tavecchio, F.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies
Abstract: We present more than three years of observations at different frequencies, from radio to high-energy gamma-rays, of the Narrow-Line Seyfert 1 (NLS1) Galaxy PMN J0948+0022 (z=0.585). This source is the first NLS1 detected at energies above 100 MeV and therefore can be considered the prototype of this emerging new class of gamma-ray emitting active galactic nuclei (AGN). The observations performed from 2008 August 1 to 2011 December 31 confirmed that PMN J0948+0022 generates a powerful relativistic jet, able to develop an isotropic luminosity at gamma-rays of the order of 10^48 erg s^-1, at the level of powerful quasars. The evolution of the radiation emission of this source in 2009 and 2010 followed the canonical expectations of relativistic jets, with correlated multiwavelength variability (gamma-rays followed by radio emission after a few months), but it was difficult to retrieve a similar pattern in the light curves of 2011. The comparison of gamma-ray spectra before and including 2011 data suggested that there was a softening of the high-energy spectral slope. We selected five specific epochs to be studied by modelling the broad-band spectrum, characterised by an outburst at gamma-rays or very low/high flux at other wavelengths. The observed variability can largely be explained either by changes in the injected power, the bulk Lorentz factor of the jet or the electron spectrum. The characteristic time scale of doubling/halving flux ranges from a few days to a few months, depending on the frequency and the sampling rate. The shortest doubling time scale at gamma-rays is 2.3+-0.5 days. These small values underline the need of highly-sampled multiwavelength campaigns to better understand the physics of these sources., Comment: 15 pages, Accepted for publication on Astronomy and Astrophysics Main Journal
Published: 2012
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44. Planck Intermediate Results. V. Pressure profiles of galaxy clusters from the Sunyaev-Zeldovich effect

Author: Planck Collaboration, Ade, P. A. R., Aghanim, N., Arnaud, M., Ashdown, M., Atrio-Barandela, F., Aumont, J., Baccigalupi, C., Balbi, A., Banday, A. J., Barreiro, R. B., Bartlett, J. G., Battaner, E., Benabed, K., Benoit, A., Bernard, J. -P., Bersanelli, M., Bhatia, R., Bikmaev, I., Boehringer, H., Bonaldi, A., Bond, J. R., Borgani, S., Borrill, J., Bouchet, F. R., Bourdin, H., Brown, M. L., Burenin, R., Burigana, C., Cabella, P., Cardoso, J. -F., Carvalho, P., Castex, G., Catalano, A., Cayon, L., Chamballu, A., Chiang, L. -Y, Chon, G., Christensen, P. R., Churazov, E., Clements, D. L., Colafrancesco, S., Colombi, S., Colombo, L. P. L., Comis, B., Coulais, A., Crill, B. P., Cuttaia, F., Da Silva, A., Dahle, H., Danese, L., Davis, R. J., de Bernardis, P., de Gasperis, G., de Zotti, G., Delabrouille, J., Democles, J., Desert, F. -X., Diego, J. M., Dolag, K., Dole, H., Donzelli, S., Dore, O., Dorl, U., Douspis, M., Dupac, X., Efstathiou, G., Ensslin, T. A., Eriksen, H. K., Finelli, F., Flores-Cacho, I., Forni, O., Fosalba, P., Frailis, M., Franceschi, E., Frommert, M., Galeotta, S., Ganga, K., Genova-Santos, R. T., Giard, M., Giraud-Heraud, Y., Gonzalez-Nuevo, J., Gorski, K. M., Gregorio, A., Gruppuso, A., Hansen, F. K., Harrison, D., Hempel, A., Henrot-Versille, S., Hernandez-Monteagudo, C., Herranz, D., Hildebrandt, S. R., Hivon, E., Hobson, M., Holmes, W. A., Hurier, G., Jaffe, T. R., Jaffe, A. H., Jagemann, T., Jones, W. C., Juvela, M., Keihanen, E., Khamitov, I., Kisner, T. S., Kneissl, R., Knoche, J., Knox, L., Kunz, M., Kurki-Suonio, H., Lagache, G., Lahteenmaki, A., Lamarre, J. -M., Lasenby, A., Lawrence, C. R., Jeune, M. Le, Leonardi, R., Liddle, A., Lilje, P. B., Lopez-Caniego, M., Luzzi, G., Macias-Perez, J. F., Maino, D., Mandolesi, N., Maris, M., Marleau, F., Marshall, D. J., Martinez-Gonzalez, E., Masi, S., Massardi, M., Matarrese, S., Mazzotta, P., Mei, S., Melchiorri, A., Melin, J. -B., Mendes, L., Mennella, A., Mitra, S., Miville-Deschaines, M. -A., Moneti, A., Montier, L., Morgante, G., Mortlock, D., Munshi, D., Murphy, J. A., Naselsky, P., Nati, F., Natoli, P., Norgaard-Nielsen, H. U., Noviello, F., Novikov, D., Novikov, I., Osborne, S., Pajot, F., Paoletti, D., Pasian, F., Patanchon, G., Perdereau, O., Perotto, L., Perrotta, F., Piacentini, F., Piat, M., Pierpaoli, E., Piffaretti, R., Plaszczynski, S., Pointecouteau, E., Polenta, G., Ponthieu, N., Popa, L., Poutanen, T., Pratt, G. W., Prunet, S., Puget, J. -L., Rachen, J. P., Reach, W. T., Rebolo, R., Reinecke, M., Remazeilles, M., Renault, C., Ricciardi, S., Riller, T., Ristorcelli, I., Rocha, G., Roman, M., Rosset, C., Rossetti, M., Rubino-Martin, J. A., Rusholme, B., Sandri, M., Savini, G., Scott, D., Smoot, G. F., Starck, J. -L., Sudiwala, R., Sunyaev, R., Sutton, D., Suur-Uski, A. -S., Sygnet, J. -F., Tauber, J. A., Terenzi, L., Toffolatti, L., Tomasi, M., Tristram, M., Tuovinen, J., Valenziano, L., Van Tent, B., Varis, J., Vielva, P., Villa, F., Vittorio, N., Wade, L. A., Wandelt, B. D., Welikala, N., White, S. D. M., White, M., Yvon, D., Zacchei, A., and Zonca, A.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Taking advantage of the all-sky coverage and broad frequency range of the Planck satellite, we study the Sunyaev-Zeldovich (SZ) and pressure profiles of 62 nearby massive clusters detected at high significance in the 14-month nominal survey. Careful reconstruction of the SZ signal indicates that most clusters are individually detected at least out to R500. By stacking the radial profiles, we have statistically detected the radial SZ signal out to 3 x R500, i.e., at a density contrast of about 50-100, though the dispersion about the mean profile dominates the statistical errors across the whole radial range. Our measurement is fully consistent with previous Planck results on integrated SZ fluxes, further strengthening the agreement between SZ and X-ray measurements inside R500. Correcting for the effects of the Planck beam, we have calculated the corresponding pressure profiles. This new constraint from SZ measurements is consistent with the X-ray constraints from XMM-Newton in the region in which the profiles overlap (i.e., [0.1-1]R500), and is in fairly good agreement with theoretical predictions within the expected dispersion. At larger radii the average pressure profile is slightly flatter than most predictions from numerical simulations. Combining the SZ and X-ray observed profiles into a joint fit to a generalised pressure profile gives best-fit parameters [P0, c500, gamma, alpha, beta] = [6.41, 1.81, 0.31, 1.33, 4.13]. Using a reasonable hypothesis for the gas temperature in the cluster outskirts we reconstruct from our stacked pressure profile the gas mass fraction profile out to 3 x R500. Within the temperature driven uncertainties, our Planck constraints are compatible with the cosmic baryon fraction and expected gas fraction in halos., Comment: 24 pages, 15 figures, accepted for publication in A&A
Published: 2012
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45. Multi-wavelength observations of blazar AO 0235+164 in the 2008-2009 flaring state

Author: Ackermann, M., Ajello, M., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bottacini, E., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cutini, S., D'Ammando, F., de Palma, F., Dermer, C. D., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Dubois, R., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Fortin, P., Fuhrmann, L., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Hadasch, D., Hayashida, M., Hughes, R. E., Itoh, R., Johannesson, G., Johnson, A. S., Katagiri, H., Kataoka, J., Knodlseder, J., Kuss, M., Lande, J., Larsson, S., Lee, S. -H., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Nishino, S., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ozaki, M., Paneque, D., Panetta, J. H., Pelassa, V., Pesce-Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Porter, T. A., Raino, S., Rando, R., Rastawicki, D., Razzano, M., Readhead, A., Reimer, A., Reimer, O., Reyes, L. C., Richards, J. L., Sbarra, C., Sgro, C., Siskind, E. J., Spandre, G., Spinelli, P., Szostek, A., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Winer, B. L., Wood, K. S., Yang, Z., Zimmer, S., Moderski, R., Nalewajko, K., Sikora, M., Villata, M., Raiteri, C. M., Aller, H. D., Aller, M. F., Arkharov, A. A., Benitez, E., Berdyugin, A., Blinov, D. A., Boettcher, M., Calle, O. J. A. Bravo, Buemi, C. S., Carosati, D., Chen, W. P., Diltz, C., Di Paola, A., Dolci, M., Efimova, N. V., Forn\', E., Gurwell, M. A., Heidt, J., Hiriart, D., Jordan, B., Kimeridze, G., Konstantinova, T. S., Kopatskaya, E. N., Koptelova, E., Kurtanidze, O. M., Lahteenmaki, A., Larionova, E. G., Larionova, L. V., Larionov, V. M., Leto, P., Lindfors, E., Lin, H. C., Morozova, D. A., Nikolashvili, M. G., Nilsson, K., Oksman, M., Roustazadeh, P., Sievers, A., Sigua, L. A., Sillanpaa, A., Takahashi, T., Takalo, L. O., Tornikoski, M., Trigilio, C., Troitsky, I. S., Umana, G., Angelakis, E., Krichbaum, T. P., Nestoras, I., Riquelme, D., Krips, M., Trippe, S., Arai, A., Kawabata, K. S., Sakimoto, K., Sasada, M., Sato, S., Uemura, M., Yamanaka, M., Yoshida, M., Belloni, T., Tagliaferri, G., Bonning, E. W., Isler, J., Urry, C. M., Hoversten, E., Falcone, A., Pagani, C., and Stroh, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The blazar AO 0235+164 (z = 0.94) has been one of the most active objects observed by Fermi Large Area Telescope (LAT) since its launch in Summer 2008. In addition to the continuous coverage by Fermi, contemporaneous observations were carried out from the radio to {\gamma} -ray bands between 2008 September and 2009 February. In this paper, we summarize the rich multi-wavelength data collected during the campaign (including F-GAMMA, GASP- WEBT, Kanata, OVRO, RXTE, SMARTS, Swift, and other instruments), examine the cross-correlation between the light curves measured in the different energy bands, and interpret the resulting spectral energy distributions in the context of well-known blazar emission models. We find that the {\gamma} -ray activity is well correlated with a series of near-IR/optical flares, accompanied by an increase in the optical polarization degree. On the other hand, the X-ray light curve shows a distinct 20 day high state of unusually soft spectrum, which does not match the extrapolation of the optical/UV synchrotron spectrum. We tentatively interpret this feature as the bulk Compton emission by cold electrons contained in the jet, which requires an accretion disk corona with an effective covering factor of 19% at a distance of 100 Rg . We model the broadband spectra with a leptonic model with external radiation dominated by the infrared emission from the dusty torus., Comment: 48 pages, 8 figures
Published: 2012
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46. The structure and emission model of the relativistic jet in the quasar 3C 279 inferred from radio to high-energy gamma-ray observations in 2008-2010

Author: Hayashida, M., Madejski, G. M., Nalewajko, K., Sikora, M., Wehrle, A. E., Ogle, P., Collmar, W., Larsson, S., Fukazawa, Y., Itoh, R., Chiang, J., Stawarz, L., Blandford, R. D., Richards, J. L., Max-Moerbeck, W., Readhead, A., Buehler, R., Cavazzuti, E., Ciprini, S., Gehrels, N., Reimer, A., Szostek, A., Tanaka, T., Tosti, G., Uchiyama, Y., Kawabata, K. S., Kino, M., Sakimoto, K., Sasada, M., Sato, S., Uemura, M., Yamanaka, M., Greiner, J., Kruehler, T., Rossi, A., Macquart, J. P., Bock, D. C. -J., Villata, M., Raiteri, C. M., Agudo, I., Aller, H. D., Aller, M. F., Arkharov, A. A., Bach, U., Benitez, E., Berdyugin, A., Blinov, D. A., Blumenthal, K., Boettcher, M., Buemi, C. S., Carosati, D., Chen, W. P., Di Paola, A., Dolci, M., Efimova, N. V., Forne, E., Gomez, J. L., Gurwell, M. A., Heidt, J., Hiriart, D., Jordan, B., Jorstad, S. G., Joshi, M., Kimeridze, G., Konstantinova, T. S., Kopatskaya, E. N., Koptelova, E., Kurtanidze, O. M., Lahteenmaki, A., Lamerato, A., Larionov, V. M., Larionova, E. G., Larionova, L. V., Leto, P., Lindfors, E., Marscher, A. P., McHardy, I. M., Molina, S. N., Morozova, D. A., Nikolashvili, M. G., Nilsson, K., Reinthal, R., Roustazadeh, P., Sakamoto, T., Sigua, L. A., Sillanpaa, A., Takalo, L., Tammi, J., Taylor, B., Tornikoski, M., Trigilio, C., Troitsky, I. S., and Umana, G.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We present time-resolved broad-band observations of the quasar 3C 279 obtained from multi-wavelength campaigns conducted during the first two years of the Fermi Gamma-ray Space Telescope mission. While investigating the previously reported gamma-ray/optical flare accompanied by a change in optical polarization, we found that the optical emission appears delayed with respect to the gamma-ray emission by about 10 days. X-ray observations reveal a pair of `isolated' flares separated by ~90 days, with only weak gamma-ray/optical counterparts. The spectral structure measured by Spitzer reveals a synchrotron component peaking in the mid-infrared band with a sharp break at the far-infrared band during the gamma-ray flare, while the peak appears in the mm/sub-mm band in the low state. Selected spectral energy distributions are fitted with leptonic models including Comptonization of external radiation produced in a dusty torus or the broad-line region. Adopting the interpretation of the polarization swing involving propagation of the emitting region along a curved trajectory, we can explain the evolution of the broad-band spectra during the gamma-ray flaring event by a shift of its location from ~ 1 pc to ~ 4 pc from the central black hole. On the other hand, if the gamma-ray flare is generated instead at sub-pc distance from the central black hole, the far-infrared break can be explained by synchrotron self-absorption. We also model the low spectral state, dominated by the mm/sub-mm peaking synchrotron component, and suggest that the corresponding inverse-Compton component explains the steady X-ray emission., Comment: 23 pages, 18 figures 5 tables, Accepted for publication in The Astrophysical Journal
Published: 2012
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47. Exploring the relation between (sub-)millimeter radiation and gamma-ray emission in blazars with Planck and Fermi

Author: Leon-Tavares, J., Valtaoja, E., Giommi, P., Polenta, G., Tornikoski, M., Lahteenmaki, A., Gasparrini, D., and Cutini, S.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: The coexistence of Planck and Fermi satellites in orbit has enabled the exploration of the connection between the (sub-)millimeter and gamma-ray emission in a large sample of blazars. We find that the gamma-ray emission and the (sub-)mm luminosities are correlated over five orders of magnitude. However, this correlation is not significant at some frequency bands when simultaneous observations are considered. The most significant statistical correlations, on the other hand, arise when observations are quasi-simultaneous within 2 months. Moreover, we find that sources with an approximate spectral turnover in the middle of the mm-wave regime are more likely to be strong gamma-ray emitters. These results suggest a physical relation between the newly injected plasma components in the jet and the high levels of gamma-ray emission., Comment: 39 pages, 6 figures. Accepted for publication in ApJ; for an emulated ApJ version, see http://www.metsahovi.fi/~leon/submm_gamma/ms_16apr12.pdf
Published: 2012
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48. VLBI and Single Dish Monitoring of 3C84 in the Period of 2009-2011

Author: Nagai, Hiroshi, Orienti, Monica, Kino, Motoki, Suzuki, Kenta, Giovannini, Gabriele, Doi, Akihiro, Asada, Keiichi, Giroletti, Marcello, Kataoka, Jun, D'Ammando, Filippo, Inoue, Makoto, Lahteenmaki, Anne, Tornikoski, Merja, Leon-Tavares, Jonathan, Kameno, Seiji, and Bach, Uwe
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The radio galaxy 3C 84 is a representative of gamma-ray-bright misaligned active galactic nuclei (AGNs) and one of the best laboratories to study the radio properties of the sub-pc jet in connection with the gamma-ray emission. In order to identify possible radio counterparts of the gamma-ray emissions in 3C 84, we study the change in structure within the central 1 pc and the light curve of sub-pc-size components C1, C2, and C3. We search for any correlation between changes in the radio components and the gamma-ray flares by making use of VLBI and single dish data. Throughout the radio monitoring spanning over two GeV gamma-ray flares detected by the {\it Fermi}-LAT and the MAGIC Cherenkov Telescope in the periods of 2009 April to May and 2010 June to August, total flux density in radio band increases on average. This flux increase mostly originates in C3. Although the gamma-ray flares span on the timescale of days to weeks, no clear correlation with the radio light curve on this timescale is found. Any new prominent components and change in morphology associated with the gamma-ray flares are not found on the VLBI images., Comment: 6 pages, 3 figures, accepted for publication in MNRAS letter
Published: 2012
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49. Location of the Gamma-Ray Flaring Emission in the Parse-Scale Jet of the BL Lac Object AO 0235+164

Author: Agudo, Ivan, Marscher, Alan P., Jorstad, Svetlana G., Larionov, Valeri M., Gomez, Jose L., Lahteenmaki, Anne, Smith, Paul S., Nilsson, Kari, Readhead, Anthony C. S., Aller, Margo F., Heidt, Jochen, Gurwell, Mark, Thum, Clemens, Wehrle, Ann E., and Kurtanidze, Omar M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: We locate the gamma-ray and lower frequency emission in flares of the BL Lac object AO 0235+164 at >12pc in the jet of the source from the central engine. We employ time-dependent multi-spectral-range flux and linear polarization monitoring observations, as well as ultra-high resolution (~0.15 milliarcsecond) imaging of the jet structure at lambda=7mm. The time coincidence in the end of 2008 of the propagation of the brightest superluminal feature detected in AO 0235+164 (Qs) with an extreme multi-spectral-range (gamma-ray to radio) outburst, and an extremely high optical and 7mm (for Qs) polarization degree provides strong evidence supporting that all these events are related. This is confirmed at high significance by probability arguments and Monte-Carlo simulations. These simulations show the unambiguous correlation of the gamma-ray flaring state in the end of 2008 with those in the optical, millimeter, and radio regime, as well as the connection of a prominent X-ray flare in October 2008, and of a series of optical linear polarization peaks, with the set of events in the end of 2008. The observations are interpreted as the propagation of an extended moving perturbation through a re-collimation structure at the end of the jet's acceleration and collimation zone., Comment: To be published in the proceedings of High Energy Phenomena in Relativistic Outflows III (HEPRO III, IJMPCS). 6 pages
Published: 2011
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50. Multiwavelength Spectral Studies Of Fermi-LAT Blazars

Author: Joshi, Manasvita, Marscher, Alan, Jorstad, Svetlana, Boettcher, Markus, Agudo, Ivan, Larionov, Valeri, Aller, Margo, Gurwell, Mark, and Lahteenmaki, Anne
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present multiwavelength spectral analyses of two Fermi-LAT blazars, OJ 287 and 3C 279, that are part of the Boston University multiwaveband polarization program. The data have been compiled from observations with Fermi, RXTE, the VLBA, and various ground-based optical and radio telescopes. We simulate the dynamic spectral energy distributions (SEDs) within the framework of a multi-slice, time-dependent leptonic jet model for blazars, with radiation feedback, in the internal shock scenario. We use the physical jet parameters obtained from the VLBA monitoring to guide our modeling efforts. We discuss the role of intrinsic parameters and the interplay between synchrotron and inverse Compton radiation processes responsible for producing the resultant SEDs., Comment: 2011 Fermi Symposium proceedings - eConf C110509; 4 pages, 6 figures
Published: 2011

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