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Fermi Bubble: Giant Gamma-Ray Bubbles in the Milky Way

Conference paper
Part of the Astrophysics and Space Science Proceedings book series (ASSSP, volume 34)

Abstract

Data from the Fermi-LAT reveal two gigantic gamma-ray emitting bubble structures (known as the Fermibubbles), extending∼​​​​ 50 above and below the Galactic center symmetric about the Galactic plane, with a width of∼​​ 40 in longitude. The gamma-ray emission associated with these bubbles has a significantly harder spectrum \((\mathit{dN}/\mathit{dE} \sim {E}^{-2})\) than the inverse Compton emission from known cosmic ray electrons in the Galactic disk, or the gamma-rays produced by decay of pions from proton-ISM collisions. The bubbles are spatially correlated with the hard-spectrum microwave excess known as the WMAPhaze; the edges of the bubbles also line up with features in the ROSATsoft X-ray maps at 1.5–2keV. The Fermibubble is most likely created by some large episode of energy injection in the Galactic center, such as past accretion events onto the central massive black hole, or a nuclear starburst in the last∼10Myr. Study of the origin and evolution of the bubbles also has the potential to improve our understanding of recent energetic events in the inner Galaxy and the high-latitude cosmic ray population.

Keywords

Wilkinson Microwave Anisotropy Probe Galactic Plane Dark Matter Annihilation Starburst Galaxy Hard Spectrum 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgements

The author acknowledges Douglas Finkbeiner and Tracy Slatyer for their wonderful collaborations on the discovery paper of the Fermi bubbles. Most of the materials in this chapter is based on this paper. The author also acknowledges stimulating conversations with Roland Crocker, Greg Dobler, Martin Elvis, Jonathan Grindlay, Fulai Guo, Christine Jones, Avi Loeb, Sera Markoff, Igor Moskalenko, Ramesh Narayan, Aneta Siemiginowska, Andrew Strong, and Feng Yuan. The author would also like to warmly thank Olaf Reimer and Diego Torres for organizing the 2nd Sant Cugat Forum on Astrophysics, “2012: Cosmic-ray phenomenology in star-forming environments”, and their great effort to make the publication of this conference book possible.

References

  1. 1.
    Abdo, A. A., et al. 2010. The Spectrum of the Isotropic Diffuse Gamma-Ray Emission Derived From First-Year Fermi Large Area Telescope Data. Phys. Rev. Lett., 104:101101.ADSCrossRefGoogle Scholar
  2. 2.
    Alvarez-Muñiz, J., R. Engel, & T. Stanev 2002. Ultrahigh-Energy Cosmic-Ray Propagation in the Galaxy: Clustering versus Isotropy. ApJ, 572:185–201.ADSCrossRefGoogle Scholar
  3. 3.
    Atwood, W. B., A. A. Abdo, M. Ackermann, W. Althouse, B. Anderson, M. Axelsson, L. Baldini, J. Ballet, D. L. Band, G. Barbiellini, J. Bartelt, D. Bastieri, B. M. Baughman, K. Bechtol, D. Bédérède, F. Bellardi, R. Bellazzini, B. Berenji, G. F. Bignami, D. Bisello, E. Bissaldi, R. D. Blandford, E. D. Bloom, J. R. Bogart, E. Bonamente, J. Bonnell, A. W. Borgland, A. Bouvier, J. Bregeon, A. Brez, M. Brigida, P. Bruel, T. H. Burnett, G. Busetto, G. A. Caliandro, R. A. Cameron, P. A. Caraveo, S. Carius, P. Carlson, J. M. Casandjian, E. Cavazzuti, M. Ceccanti, C. Cecchi, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, R. Chipaux, A. N. Cillis, S. Ciprini, R. Claus, J. Cohen-Tanugi, S. Condamoor, J. Conrad, R. Corbet, L. Corucci, L. Costamante, S. Cutini, D. S. Davis, D. Decotigny, M. DeKlotz, C. D. Dermer, A. de Angelis, S. W. Digel, E. do Couto e Silva, P. S. Drell, R. Dubois, D. Dumora, Y. Edmonds, D. Fabiani, C. Farnier, C. Favuzzi, D. L. Flath, P. Fleury, W. B. Focke, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, F.-X. Gentit, S. Germani, B. Giebels, N. Giglietto, P. Giommi, F. Giordano, T. Glanzman, G. Godfrey, I. A. Grenier, M.-H. Grondin, J. E. Grove, L. Guillemot, S. Guiriec, G. Haller, A. K. Harding, P. A. Hart, E. Hays, S. E. Healey, M. Hirayama, L. Hjalmarsdotter, R. Horn, R. E. Hughes, G. Jóhannesson, G. Johansson, A. S. Johnson, R. P. Johnson, T. J. Johnson, W. N. Johnson, T. Kamae, H. Katagiri, J. Kataoka, A. Kavelaars, N. Kawai, H. Kelly, M. Kerr, W. Klamra, J. Knödlseder, M. L. Kocian, N. Komin, F. Kuehn, M. Kuss, D. Landriu, L. Latronico, B. Lee, S.-H. Lee, M. Lemoine-Goumard, A. M. Lionetto, F. Longo, F. Loparco, B. Lott, M. N. Lovellette, P. Lubrano, G. M. Madejski, A. Makeev, B. Marangelli, M. M. Massai, M. N. Mazziotta, J. E. McEnery, N. Menon, C. Meurer, P. F. Michelson, M. Minuti, N. Mirizzi, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, S. Nishino, P. L. Nolan, J. P. Norris, E. Nuss, M. Ohno, T. Ohsugi, N. Omodei, E. Orlando, J. F. Ormes, A. Paccagnella, D. Paneque, J. H. Panetta, D. Parent, M. Pearce, M. Pepe, A. Perazzo, M. Pesce-Rollins, P. Picozza, L. Pieri, M. Pinchera, F. Piron, T. A. Porter, L. Poupard, S. Rainò, R. Rando, E. Rapposelli, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, L. C. Reyes, S. Ritz, L. S. Rochester, A. Y. Rodriguez, R. W. Romani, M. Roth, J. J. Russell, F. Ryde, S. Sabatini, H. F.-W. Sadrozinski, D. Sanchez, A. Sander, L. Sapozhnikov, P. M. S. Parkinson, J. D. Scargle, T. L. Schalk, G. Scolieri, C. Sgrò, G. H. Share, M. Shaw, T. Shimokawabe, C. Shrader, A. Sierpowska-Bartosik, E. J. Siskind, D. A. Smith, P. D. Smith, G. Spandre, P. Spinelli, J.-L. Starck, T. E. Stephens, M. S. Strickman, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Takahashi, T. Tanaka, A. Tenze, S. Tether, J. B. Thayer, J. G. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, A. Tramacere, M. Turri, T. L. Usher, N. Vilchez, V. Vitale, P. Wang, K. Watters, B. L. Winer, K. S. Wood, T. Ylinen, & M. Ziegler 2009. The Large Area Telescope on the Fermi Gamma-Ray Space Telescope Mission. ApJ, 697:1071–1102.Google Scholar
  4. 4.
    Bhat, C. L., M. R. Issa, C. J. Mayer, & A. W. Wolfendale 1985. Acceleration of cosmic rays in the Loop I ’supernova remnant’? Nature, 314:515–517.ADSCrossRefGoogle Scholar
  5. 5.
    Biermann, P. L., J. K. Becker, G. Caceres, A. Meli, E.-S. Seo, & T. Stanev 2010. The WMAP Haze from the Galactic Center Region Due to Massive Star Explosions and a Reduced Cosmic Ray Scale Height. ApJ, 710:L53–L57.ADSCrossRefGoogle Scholar
  6. 6.
    Bloemen, H. 1989. Diffuse Galactic gamma-ray emission. ARA&A, 27:469–516.ADSCrossRefGoogle Scholar
  7. 7.
    Blumenthal, G. R., & R. J. Gould 1970. Bremsstrahlung, Synchrotron Radiation, and Compton Scattering of High-Energy Electrons Traversing Dilute Gases. Reviews of Modern Physics, 42:237–271.ADSCrossRefGoogle Scholar
  8. 8.
    Casandjian, J.-M., I. Grenier, & for the Fermi Large Area Telescope Collaboration 2009. High Energy Gamma-Ray Emission from the Loop I region. ArXiv e-prints.Google Scholar
  9. 9.
    Cholis, I., G. Dobler, D. P. Finkbeiner, L. Goodenough, T. R. Slatyer, & N. Weiner 2009. The Fermi gamma-ray spectrum of the inner galaxy: Implications for annihilating dark matter. ArXiv e-prints.Google Scholar
  10. 10.
    Dame, T. M., D. Hartmann, & P. Thaddeus 2001. The Milky Way in Molecular Clouds: A New Complete CO Survey. ApJ, 547:792–813.ADSCrossRefGoogle Scholar
  11. 11.
    Dixon, D. D., D. H. Hartmann, E. D. Kolaczyk, J. Samimi, R. Diehl, G. Kanbach, H. Mayer-Hasselwander, & A. W. Strong 1998. Evidence for a Galactic gamma-ray halo. New Astronomy, 3:539–561.ADSCrossRefGoogle Scholar
  12. 12.
    Dobler, G., & D. P. Finkbeiner 2008. Extended Anomalous Foreground Emission in the WMAP Three-Year Data. ApJ, 680:1222–1234.ADSCrossRefGoogle Scholar
  13. 13.
    Dobler, G., D. P. Finkbeiner, I. Cholis, T. Slatyer, & N. Weiner 2010. The Fermi Haze: A Gamma-ray Counterpart to the Microwave Haze. ApJ, 717:825–842.ADSCrossRefGoogle Scholar
  14. 14.
    Fichtel, C. E., R. C. Hartman, D. A. Kniffen, D. J. Thompson, H. Ogelman, M. E. Ozel, T. Tumer, & G. F. Bignami 1975. High-energy gamma-ray results from the second small astronomy satellite. ApJ, 198:163–182.ADSCrossRefGoogle Scholar
  15. 15.
    Finkbeiner, Douglas P. 2004a. Microwave ISM Emission Observed by WMAP. Astrophys. J., 614:186–193.ADSCrossRefGoogle Scholar
  16. 16.
    Finkbeiner, Douglas P. 2004b. WMAP microwave emission interpreted as dark matter annihilation in the inner Galaxy.Google Scholar
  17. 17.
    Gehrels, N., & P. Michelson 1999. GLAST: The next-generation high energy gamma-ray astronomy mission. Astropart. Phys., 11:277–282.ADSCrossRefGoogle Scholar
  18. 18.
    Grenier, I. A., J.-M. Casandjian, & R. Terrier 2005. Unveiling Extensive Clouds of Dark Gas in the Solar Neighborhood. Science, 307:1292–1295.ADSCrossRefGoogle Scholar
  19. 19.
    Haslam, C. G. T., C. J. Salter, H. Stoffel, & W. E. Wilson 1982. A 408 MHz all-sky continuum survey. II - The atlas of contour maps. A&AS, 47:1– + .Google Scholar
  20. 20.
    Hooper, Dan, Douglas P. Finkbeiner, & Gregory Dobler 2007. Evidence Of Dark Matter Annihilations In The WMAP Haze. Phys. Rev., D76:083012.ADSGoogle Scholar
  21. 21.
    Jones, F. C., & D. C. Ellison 1991. The plasma physics of shock acceleration. Space Science Reviews, 58:259–346.ADSCrossRefGoogle Scholar
  22. 22.
    Kalberla, P. M. W., W. B. Burton, D. Hartmann, E. M. Arnal, E. Bajaja, R. Morras, & W. G. L. Pöppel 2005. The Leiden/Argentine/Bonn (LAB) Survey of Galactic HI. Final data release of the combined LDS and IAR surveys with improved stray-radiation corrections. A&A, 440:775–782.Google Scholar
  23. 23.
    Kaplinghat, Manoj, Daniel J. Phalen, & Kathryn M. Zurek 2009. Pulsars as the Source of the WMAP Haze. JCAP, 0912:010.ADSCrossRefGoogle Scholar
  24. 24.
    Koyama, K., Y. Maeda, T. Sonobe, T. Takeshima, Y. Tanaka, & S. Yamauchi 1996. ASCA View of Our Galactic Center: Remains of Past Activities in X-Rays? PASJ, 48:249–255.ADSGoogle Scholar
  25. 25.
    Large, M. I., M. J. S. Quigley, & C. G. T. Haslam 1962. A new feature of the radio sky. MNRAS, 124:405– + .Google Scholar
  26. 26.
    McNamara, B. R., & P. E. J. Nulsen 2007. Heating Hot Atmospheres with Active Galactic Nuclei. ARA&A, 45:117–175.ADSCrossRefGoogle Scholar
  27. 27.
    Page, L., et al. 2007. Three year Wilkinson Microwave Anisotropy Probe (WMAP) observations: Polarization analysis. Astrophys. J. Suppl., 170:335.ADSCrossRefGoogle Scholar
  28. 28.
    Paumard, T., R. Genzel, F. Martins, S. Nayakshin, A. M. Beloborodov, Y. Levin, S. Trippe, F. Eisenhauer, T. Ott, S. Gillessen, R. Abuter, J. Cuadra, T. Alexander, & A. Sternberg 2006. The Two Young Star Disks in the Central Parsec of the Galaxy: Properties, Dynamics, and Formation. ApJ, 643:1011–1035.ADSCrossRefGoogle Scholar
  29. 29.
    Schlegel, David J., Douglas P. Finkbeiner, & Marc Davis 1998. Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds. Astrophys. J., 500:525.ADSCrossRefGoogle Scholar
  30. 30.
    Smialkowski, A., A. W. Wolfendale, & L. Zhang 1997. The ‘extragalactic’ diffuse gamma ray intensity. Astroparticle Physics, 7:21–25.ADSCrossRefGoogle Scholar
  31. 31.
    Snowden, S. L. 2009. What Can Be Learned from X-ray Spectroscopy Concerning Hot Gas in the Local Bubble and Charge Exchange Processes? Space Sci. Rev., 143:253–262.Google Scholar
  32. 32.
    Strong, A. W. 1984. COS-B studies of high-latitude gamma rays. Advances in Space Research, 3:87–89.ADSCrossRefGoogle Scholar
  33. 33.
    Strong, A. W., H. A. Mayer-Hasselwander, J. B. G. M. Bloemen, W. Hermsen, & F. Lebrun 1987. The final COS-B database - In-flight calibration of sensitivity and instrumental background behaviour. A&AS, 67:283–296.ADSGoogle Scholar
  34. 34.
    Strong, A. W., & I. V. Moskalenko 1999. The GALPROP program for cosmic-ray propagation: new developments. 4:255–258.Google Scholar
  35. 35.
    Strong, A. W., I. V. Moskalenko, T. A. Porter, G. Jóhannesson, E. Orlando, & S. W. Digel 2009. The GALPROP Cosmic-Ray Propagation Code. ArXiv e-prints.Google Scholar
  36. 36.
    Strong, A. W., I. V. Moskalenko, & V. S. Ptuskin 2007. Cosmic-Ray Propagation and Interactions in the Galaxy. Annual Review of Nuclear and Particle Science, 57:285–327.ADSCrossRefGoogle Scholar
  37. 37.
    Su, M., T. R. Slatyer, & D. P. Finkbeiner 2010. Giant Gamma-ray Bubbles from Fermi-LAT: Active Galactic Nucleus Activity or Bipolar Galactic Wind? ApJ, 724:1044–1082.ADSCrossRefGoogle Scholar
  38. 38.
    Sun, X. H., W. Reich, A. Waelkens, & T. A. Enßlin 2008. Radio observational constraints on Galactic 3D-emission models. A&A, 477:573–592.ADSCrossRefGoogle Scholar
  39. 39.
    Sunyaev, R. A., M. Markevitch, & M. Pavlinsky 1993. The center of the Galaxy in the recent past - A view from GRANAT. ApJ, 407:606–610.ADSCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Institute for Theory and ComputationHarvard-Smithsonian Center for AstrophysicsCambridgeUSA

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