1932

Abstract

This article reviews the recent observational results regarding γ-ray emission from active galaxies. The most numerous discrete extragalactic γ-ray sources are AGNs dominated by relativistic jets pointing in our direction (commonly known as blazars), and they are the main subject of the review. They are detected in all observable energy bands and are highly variable. The advent of the sensitive γ-ray observations, afforded by the launch and continuing operation of the and the AGILE Gamma-ray Imaging Detector, as well as by the deployment of current-generation Air Cerenkov Telescope arrays such as VERITAS, MAGIC, and HESS-II, continually provides sensitive γ-ray data over the energy range of ∼100 MeV to multi-TeV. Importantly, it has motivated simultaneous, monitoring observations in other bands, resulting in unprecedented time-resolved broadband spectral coverage. After an introduction, in Sections 3, 4, and 5, we cover the current status and highlights of γ-ray observations with (mainly) but also AGILE and put those in the context of broadband spectra in Section 6. We discuss the radiation processes operating in blazars in Section 7, and we discuss the content of their jets and the constraints on the location of the energy dissipation regions in, respectively, Sections 8 and 9. Section 10 covers the current ideas for particle acceleration processes in jets, and Section 11 discusses the coupling of the jet to the accretion disk in the host galaxy. Finally, Sections 12, 13, and 14 cover, respectively, the contribution of blazars to the diffuse γ-ray background, the utility of blazars to study the extragalactic background light, and the insight they provide for study of populations of supermassive black holes early in the history of the Universe.

Loading

Article metrics loading...

/content/journals/10.1146/annurev-astro-081913-040044
2016-09-19
2024-03-28
Loading full text...

Full text loading...

/deliver/fulltext/astro/54/1/annurev-astro-081913-040044.html?itemId=/content/journals/10.1146/annurev-astro-081913-040044&mimeType=html&fmt=ahah

Literature Cited

  1. Abdo A, Ackermann M, Agudo I. et al. 2010a. Ap. J. 716:30
  2. Abdo A, Ackermann M, Ajello M. et al. 2009. Ap. J. 699:817
  3. Abdo A, Ackermann M, Ajello M. et al. 2010b. Ap. J. 715:429
  4. Abdo A, Ackermann M, Ajello M. et al. 2010c. Ap. J. 722:520
  5. Abdo A, Ackermann M, Ajello M. et al. 2010d. Nature 463:919
  6. Abdo A, Ackermann M, Ajello M. et al. 2011. Ap. J. 733:L26
  7. Abeysekara AU, Alfaro R, Alvarez C. et al. 2015a. Astropart. Phys. 62:125
  8. Abeysekara A, Archambault S, Archer A. et al. 2015b. Ap. J. Lett. 815:L22
  9. Abramowski A, Acero F, Aharonian F. et al. 2013. Astron. Astrophys. 554:A107
  10. Acero F, Ackermann M, Ajello M. et al. 2015. Ap. J. (Suppl.) 218:23
  11. Ackermann M, Ajello M, Albert A. et al. 2015a. Ap. J. Lett. 813:L41
  12. Ackermann M, Ajello M, Allafort A. et al. 2011. Ap. J. 743:171
  13. Ackermann M, Ajello M, Allafort A. et al. 2012a. Ap. J. 755:164
  14. Ackermann M, Ajello M, Allafort A. et al. 2012b. Ap. J. 747:104
  15. Ackermann M, Ajello M, Allafort A. et al. 2013. Ap. J. 765:54
  16. Ackermann M, Ajello M, Atwood WB. et al. 2015b. Ap. J. 810:14
  17. Aharonian F. 2000. New Astronomy 5:377
  18. Aharonian F, Akhperjanian AG, Bazer-Bachi AR. et al. 2007. Ap. J. Lett. 664:L71
  19. Ahnen ML, Anslodi S, Antonelli LA. et al. 2015. Ap. J. Lett. 815:L23
  20. Ajello M, Dominguez A, Gasparini D, Cutini S. 2015b. Proc. 5th Fermi Symp., Nogoya, Japan, Oct. 20–24, 2014 eConf C14102.1
  21. Ajello M, Gasparrini D, Sánchez-Conde M. et al. 2015a. Ap. J. Lett. 800:L27
  22. Albert J, Aliu E, Anderhub H. et al. 2008. Science 320:1752
  23. Aleksić J, Anslodi S, Antonelli LA. et al. 2015a. Astropart. Phys. 72:61
  24. Aleksić J, Anslodi S, Antonelli LA. et al. 2015b. Astropart. Phys. 72:76
  25. Aleksić J, Antonelli LA, Antoranz P. et al. 2011. Ap. J. Lett. 730:L8
  26. Amato E, Arons J. 2006. Ap. J. 653:325
  27. Archambault S, Archer A, Beilicke M. et al. 2015. Ap. J. 808:110
  28. Atwood WB, Abdo A, Ackermann M. et al. 2009. Ap. J. 697:1071
  29. Baloković M, Paneque D, Madejski G. et al. 2016. Ap. J. 819:156
  30. Barbiellini G, Tavani M, Argan A. et al. 2001. Gamma 2001: Gamma-Ray Astrophys. 2001 S Ritz, N Gehrels, CR Schader AIP Conf. Proc. 587774 Melville, NY: AIP
  31. Barth A, Ho L, Sargent W. 2002. Ap. J. Lett. 566:L13
  32. Barth A, Ho L, Sargent W. 2003. Active Galactic Nuclei: From Central Engine Host Galaxy S Collin, F Combes, I Shlosman ASP Conf. Ser. 290601 San Francisco: ASP
  33. Begelman MC, Blandford R, Rees M. 1984. Rev. Mod. Phys. 56:255
  34. Begelman MC, Fabian A, Rees M. 2008. MNRAS 384:L19
  35. Begelman MC, Sikora M. 1987. Ap. J. 322:650
  36. Bell A. 1978a. MNRAS 182:147
  37. Bell A. 1978b. MNRAS 182:443
  38. Blandford R, East W, Nalewajko K, Yuan Y, Zrake J. 2015. Pubs. Acad. Mex. Cienc. Submitted. arXiv:1511.07515
  39. Blandford R, Königl A. 1979. Ap. J. 232:34
  40. Blandford R, Ostriker J. 1978. Ap. J. Lett. 221:L29
  41. Blandford R, Znajek R. 1977. MNRAS 179:433
  42. Blinov D, Pavlidou V, Papadakis I. et al. 2015. MNRAS 453:1669
  43. Blumenthal G, Gould R. 1970. Rev. Mod. Phys. 42:237
  44. Bonning E, Urry CM, Bailyn C. et al. 2012. Ap. J. 756:13
  45. Böttcher M, Chiang J. 2002. Ap. J. 581:127
  46. Böttcher M, Reimer A, Sweeney K, Prakash A. 2013. Ap. J. 768:54
  47. Casandjian J-M, Grenier I. 2008. Astron. Astrophys. 489:849
  48. Chadwick PM, Lyons K, McComb TJL. et al. 1999. Ap. J. 513:161
  49. Choi J-H, Schlosman I, Begelman MC. 2015. MNRAS 450:4411
  50. Coppi P, Aharonian F. 1997. Ap. J. Lett. 487:L9
  51. Dermer C, Schlickheiser R, Mastichiadis A. 1992. Astron. Astrophys. 256:L27
  52. Fermi E. 1949. Phys. Rev. 75:1169
  53. Finke JD, Reyes LC, Georganopoulos M. et al. 2015. Ap. J. 814:20
  54. Foschini L, Berton M, Caccianiga A. et al. 2015. Astron. Astrophys. 575:13
  55. Fossati G, Maraschi L, Celotti A, Comastri A, Ghisellini G. 1998. MNRAS 299:433
  56. Furniss A, Noda K, Boggs S. et al. 2015. Ap. J. 812:65
  57. Furniss A, Williams DA, Danforth C. et al. 2013. Ap. J. Lett. 768:L31
  58. Ghisellini G. 2011. 5th Texas Symp. Relativ. Astrophys. (Texas 2010) FA Aharonian, W Hofmann, FM Rieger AIP Conf. Proc. 1381180 Melville, NY: AIP
  59. Ghisellini G. 2012. MNRAS 424:L26
  60. Ghisellini G, Celotti A, Costamante L. 2002. Astron. Astrophys. 386:833
  61. Ghisellini G, Maraschi L, Treves A. 1985. Astron. Astrophys. 146:204
  62. Ghisellini G, Nardini M, Tagliaferri G. et al. 2013. MNRAS 428:1449
  63. Ghisellini G, Tavecchio F. 2009. MNRAS 397:985
  64. Ghisellini G, Tavecchio F, Foschini L, Ghirlanda G. 2011. MNRAS 414:2674
  65. Ghisellini G, Tavecchio F, Foschini L, Ghirlanda G, Maraschi L. 2010. MNRAS 402:497
  66. Ghisellini G, Tavecchio F, Maraschi L, Celotti A, Sbarrato T. 2014. Nature 515:376
  67. Giommi P, Padovani P, Polenta G. et al. 2012. MNRAS 420:2899
  68. Grandi P. 2012. Int. J. Mod. Phys. Conf. Ser. 8:25
  69. Gubbay J, Legg A, Robertson D. et al. 1969. Nature 224:1094
  70. Guo F, Liu Y-H, Daughton W, Li H. 2015. Ap. J. 806:167
  71. Harrison FA, Craig WW, Christensen FE. et al. 2013. Ap. J. 770:103
  72. Hartman RC, Bertsch DL, Bloom SB. et al. 1999. Ap. J. Suppl. 123:79
  73. Hayashida M, Madejski G, Nalewajko K. et al. 2012. Ap. J. 754:114
  74. Hayashida M, Nalewajko K, Madejski G. et al. 2015. Ap. J. 807:79
  75. Holder J, Aliu E, Arlen T. et al. 2011. Presented at 32nd Int. Cosmic Ray Conf, Beijing, China. arxiv:1111.1225
  76. Holder J, Atkins RW, Badran HM. et al. 2006. Astropart. Phys. 25:391
  77. Hoshino M, Arons J, Gallant YA, Langdon AB. 1992. Ap. J. 390:454
  78. Inoue Y. 2011. Ap. J. 733:66
  79. Jelley J. 1966. Nature 211:472
  80. Johnson WN, Kinzer RL, Kurfess JD. et al. 1993. Ap. J. Suppl. 86:693
  81. Jorstad S, Marscher A, Lister M. et al. 2005. Astron. J. 130:1418
  82. Katarzynski K, Ghisellini G, Mastichiadis A, Tavecchio F, Maraschi L. 2006. Astron. Astrophys. 453:47
  83. Katarzynski K, Ghisellini G, Tavecchio F. et al. 2005. Astron. Astrophys. 433:479
  84. Kellermann K, Pauliny-Toth I. 1969. Ap. J. Lett. 155:L71
  85. Königl A. 1981. Ap. J. 243:700
  86. Kormendy J, Ho L. 2013. Annu. Rev. Astron. Astrophys. 51:511
  87. Kraushaar W, Clark G, Garmire G. et al. 1972. Ap. J. 177:341
  88. Larsson S. 2012. J. Phys. Conf. Ser. 355:2029
  89. Lister ML, Aller MF, Aller HD. et al. 2013. Astron. J. 146:120
  90. Madsen K, Fuerst F, Walton D. et al. 2015. Ap. J. 812:14
  91. Mannheim K, Biermann PL. 1992. Astron. Astrophys. 253:L21
  92. Marscher A. 2014. Ap. J. 780:87
  93. Marscher A, Gear W. 1985. Ap. J. 298:114
  94. Marscher AP, Jorstad SG, D'Arcangelo FD. et al. 2008. Nature 452:966
  95. Marscher AP, Marshall FE, Mushotzky RF. et al. 1979. Ap. J. 233:498
  96. Massaro F, Thompson D, Ferrara E. 2016. Astron. Astrophys. Rev. 24:2
  97. McKinney J, Blandford R. 2009. MNRAS 394:L126
  98. McKinney J, Tchekhovskoy A, Blandford R. 2012. MNRAS 423:3083
  99. Moderski R, Sikora M, Blazejowski M. 2003. Astron. Astrophys. 406:855
  100. Nalewajko K, Begelman MC, Sikora M. 2014. Ap. J. 789:161
  101. Nalewajko K, Giannios D, Begelman MC, Uzdensky D, Sikora M. 2011. MNRAS 413:333
  102. Nalewajko K, Uzdensky D, Cerutti B, Werner GR, Begelman MC. 2015. Ap. J. 815:101
  103. Narayan R, Kumar P. 2009. MNRAS 394:L117
  104. Narayan R, Piran T. 2012. MNRAS 420:604
  105. Narayan R, Yi I. 1994. Ap. J. Lett. 428:L13
  106. Narayan R, Yi I. 1995. Ap. J. 452:710
  107. Neronov A, Semikoz D. 2006. JETP Lett. 85:473
  108. Neronov A, Semikoz D. 2009. Phys. Rev. D 80:123012
  109. Padovani P, Urry CM. 1992. Ap. J. 387:449
  110. Poutanen J, Stern B. 2010. Ap. J. Lett. 717:L118
  111. Punch M, Akerlof CW, Cawley MF. et al. 1992. Nature 358:477
  112. Punsly B, Igumenshchev I, Hirose S. 2009. Ap. J. 687:162
  113. Quinn J, Akerlof CW, Biller S. et al. 1996. Ap. J. 456:83
  114. Rando R, Buson S. 2015. Riv. Nuovo Cim. 38:209
  115. Rees M. 1966. Nature 211:468
  116. Romani R, Sowards-Emmerd D, Greenhill L, Michelson P. 2004. Ap. J. Lett. 610:L9
  117. Sanders D, Phinney ES, Neugerbauer G, Soifer BT, Matthews K. 1989. Ap. J. 347:29
  118. Sbarrato T, Ghisellini G, Nardini M. et al. 2012. MNRAS 426:L91
  119. Sbarrato T, Tagliaferri G, Ghisellini G. et al. 2013. Ap. J. 777:147
  120. Schoenfelder V, Aarts H, Bennett K. et al. 1993. Ap. J. Suppl. 86:657
  121. Shaw M, Romani R, Cotter G. et al. 2012. Ap. J. 748:49
  122. Shaw M, Romani R, Cotter G. et al. 2013. Ap. J. 764:135
  123. Sikora M. 2011. Jets at All Scales, IAU Symp. S275 G Romero, R Sunyaev, T Bellon 659 Cambridge, UK: Cambridge Univ. Press
  124. Sikora M, Begelman MC, Madejski G, Lasota J-P. 2005. Ap. J. 625:72
  125. Sikora M, Begelman MC, Rees M. 1994. Ap. J. 421:153
  126. Sikora M, Madejski G. 2000. Ap. J. 534:109
  127. Sikora M, Rutkowski M, Begelman MC. 2016. MNRAS 457:1352
  128. Sikora M, Stawarz L, Moderski R, Nalewajko K, Madejski G. 2009. Ap. J. 704:38
  129. Sillanpaa A, Haarala S, Valtonen M, Sundelius B, Byrd G. 1988. Ap. J. 325:628
  130. Sironi L, Petropoulu D, Giannios D. 2015. MNRAS 450:183
  131. Sironi L, Spitkovsky A. 2011. Ap. J. 726:75
  132. Sironi L, Spitkovsky A. 2014. Ap. J. Lett. 783:L21
  133. Sitarek J, Becerra-Gonzlez J, Dominis-Prester D. et al. 2015. Proc. 34th ICRS, Hague, The Netherlands, Jul. 30–Aug. 6. arXiv:1508.04580
  134. Soldi S, Beckmann V, Türler M. 2009. Proc. 2009 Fermi Symp., Washington, DC, Nov. 2–5 eConf C09112. arXiv:0912.2266
  135. Spada M, Ghisellini G, Lazzati D, Celotti A. 2001. MNRAS 325:1559
  136. Stawarz L, Petrosian V. 2008. Ap. J. 681:1725
  137. Stein W, O`Dell S, Strittmatter P. 1976. Annu. Rev. Astron. Astrophys. 14:173
  138. Swanenburg B, Bennet K, Bignami GF. et al. 1981. Ap. J. Lett. 243:L69
  139. Swanenburg B, Hermsen W, Bennett K. et al. 1978. Nature 275:298
  140. Tavani M, Barbiellini G, Argan A. et al. 2009. Astron. Astrophys. 502:995
  141. Tavecchio F, Ghisellini G, Bonnoli G, Foschini L. 2011. MNRAS 414:3566
  142. Tchekhovskoy A, Narayan R, McKinney J. 2011. MNRAS 418:L79
  143. The Fermi LAT Collab., Ackermann M, Ajello M, Albert A et al. 2015. J. Cosmol. Astropart. Phys. 9:8
  144. Thompson D, Bertsch DL, Fichtel CE. et al. 1993. Ap. J. Suppl. 86:629
  145. Tramacere A, Giommi P, Perri M, Verrecchia F, Tosti G. 2009. Astron. Astrophys. 501:879
  146. Tramacere A, Massaro E, Taylor A. 2011. Ap. J. 739:66
  147. Ushio M, Stawarz L, Takahashi T. et al. 2010. Ap. J. 724:1509
  148. Ushio M, Tanaka T, Madejski G. et al. 2009. Ap. J. 699:1964
  149. Vermeulen R, Ogle PM, Tran HD. et al. 1995. Ap. J. Lett. 452:L5
  150. Weekes T, Turver K. 1977. ESA Recent Advances in Gamma-ray Astronomy279
  151. Wehrle A, Grupe D, Jorstad SG. et al. 2016. Ap. J. 816:53
  152. Williams R, Pogge R, Mathur S. 2002. Astron. J. 124:30429
  153. Yuan F, Narayan R. 2014. Annu. Rev. Astron. Astrophys. 52:529
  154. Zaborov D, Romoli C, Taylor AM. et al. 2015. Proc. 34th ICRS, Hague, The Netherlands, Jul. 30–Aug. 6. arXiv:1509.06509
  155. Zdziarski A, Böttcher M. 2015. MNRAS 450:21
  156. Zhang H, Chen X, Böttcher M, Guo F, Li H. 2015. Ap. J. 804:58
  157. Zrake J, East W. 2016. Ap. J. 817:89
/content/journals/10.1146/annurev-astro-081913-040044
Loading
/content/journals/10.1146/annurev-astro-081913-040044
Loading

Data & Media loading...

  • Article Type: Review Article
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error