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BASS. XXXIII. Swift-BAT Blazars and Their Jets through Cosmic Time

Marcotulli, L. and Ajello, M. and Urry, C. M. and Paliya, V. S. and Koss, M. and Oh, K. and Madejski, G. and Ueda, Y. and Baloković, M. and Trakhtenbrot, B. and Ricci, F. and Ricci, C. and Stern, D. and Harrison, F. and Powell, M. C. (2022) BASS. XXXIII. Swift-BAT Blazars and Their Jets through Cosmic Time. Astrophysical Journal, 940 (1). Art. No. 77. ISSN 0004-637X. doi:10.3847/1538-4357/ac937f.

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We derive the most up-to-date Swift-Burst Alert Telescope (BAT) blazar luminosity function in the 14–195 keV range, making use of a clean sample of 118 blazars detected in the BAT 105 month survey catalog, with newly obtained redshifts from the BAT Active Galatic Nucleus Spectroscopic Survey. We determine the best-fit X-ray luminosity function for the whole blazar population, as well as for flat-spectrum radio quasars (FSRQs) alone. The main results are: (1) at any redshift, BAT detects the most luminous blazars, above any possible break in their luminosity distribution, which means we cannot differentiate between density and luminosity evolution; (2) the whole blazar population, dominated by FSRQs, evolves positively up to redshift z ∼ 4.3, confirming earlier results and implying lower number densities of blazars at higher redshifts than previously estimated. The contribution of this source class to the cosmic X-ray background at 14–195 keV can range from 5%–18%, while possibly accounting for 100% of the MeV background. We also derived the average 14 keV–10 GeV spectral energy distribution for BAT blazars, which allows us to predict the number counts of sources in the MeV range, as well as the expected number of high-energy (>100 TeV) neutrinos. A mission like COSI will detect 40 MeV blazars, of which two may have coincident neutrino detections. Finally, taking into account beaming selection effects, the distribution and properties of the parent population of these extragalactic jets are derived. We find that the distribution of viewing angles is quite narrow, with most sources aligned within <5° of the line of sight. Moreover, the average Lorentz factor,〈Γ〉= 8–12, is lower than previously suggested for these powerful sources.

Item Type:Article
Related URLs:
URLURL TypeDescription
Marcotulli, L.0000-0002-8472-3649
Ajello, M.0000-0002-6584-1703
Urry, C. M.0000-0002-0745-9792
Paliya, V. S.0000-0001-7774-5308
Koss, M.0000-0002-7998-9581
Oh, K.0000-0002-5037-951X
Madejski, G.0000-0002-2114-5626
Ueda, Y.0000-0001-7821-6715
Baloković, M.0000-0003-0476-6647
Trakhtenbrot, B.0000-0002-3683-7297
Ricci, F.0000-0001-5742-5980
Ricci, C.0000-0001-5231-2645
Stern, D.0000-0003-2686-9241
Harrison, F.0000-0003-2992-8024
Powell, M. C.0000-0003-2284-8603
Additional Information:We thank the anonymous referee for very insightful comments on the manuscript. The authors acknowledge funding under NASA contract 80NSSC20K0044. Support for this work was provided by NASA through the NASA Hubble Fellowship grant No. HST-HF2-51486.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. M.B. acknowledges support from the YCAA Prize Postdoctoral Fellowship. B.T. acknowledges support from the Israel Science Foundation (grant No. 1849/19) and from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No. 950533). C.R. acknowledges support from the Fondecyt Iniciacion grant 11190831 and ANID BASAL project FB210003. K.O. acknowledges support from the Korea Astronomy and Space Science Institute under the R&D program (project No. 2022-1-868-04) supervised by the Ministry of Science and ICT and from the National Research Foundation of Korea (NRF-2020R1C1C1005462). We acknowledge support from NASA through ADAP award NNH16CT03C. The Fermi LAT Collaboration acknowledges generous ongoing support from a number of agencies and institutes that have supported both the development and the operation of the LAT as well as scientific data analysis. These include the National Aeronautics and Space Administration and the Department of Energy in the United States, the Commissariatà l'Energie Atomique and the Centre National de la Recherche Scientifique/Institut National de Physique Nucléaire et de Physique des Particules in France, the Agenzia Spaziale Italiana and the Istituto Nazionale di Fisica Nucleare in Italy, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), High Energy Accelerator Research Organization (KEK) and Japan Aerospace Exploration Agency (JAXA) in Japan, and the K. A. Wallenberg Foundation, the Swedish Research Council, and the Swedish National Space Board in Sweden.
Group:Astronomy Department
Funding AgencyGrant Number
Yale Center for Astronomy and AstrophysicsUNSPECIFIED
Israel Science Foundation1849/19
European Research Council (ERC)950533
Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT)11190831
Agencia Nacional de Investigación y Desarrollo (ANID)FB210003
Korea Astronomy and Space Science Institute (KASI)2022-1-868-04
National Research Foundation of KoreaNRF-2020R1C1C1005462
Department of Energy (DOE)UNSPECIFIED
Commissariat a l'Energie Atomique (CEA)UNSPECIFIED
Centre National de la Recherche Scientifique (CNRS)UNSPECIFIED
Institut National de Physique Nucléaire et de Physique des Particules (IN2P3)UNSPECIFIED
Agenzia Spaziale Italiana (ASI)UNSPECIFIED
Istituto Nazionale di Fisica Nucleare (INFN)UNSPECIFIED
Ministry of Education, Culture, Sports, Science and Technology (MEXT)UNSPECIFIED
High Energy Accelerator Research Organization (KEK)UNSPECIFIED
Japan Aerospace Exploration Agency (JAXA)UNSPECIFIED
Knut and Alice Wallenberg FoundationUNSPECIFIED
Swedish Research CouncilUNSPECIFIED
Swedish National Space Board (SNSB)UNSPECIFIED
Issue or Number:1
Record Number:CaltechAUTHORS:20221212-796368000.25
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:118314
Deposited By: Research Services Depository
Deposited On:13 Jan 2023 16:07
Last Modified:17 Jan 2023 17:23

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