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Title: The Imprint of the Extragalactic Background Light in the Gamma-Ray Spectra of Blazars

Abstract

The light emitted by stars and accreting compact objects through the history of the universe is encoded in the intensity of the extragalactic background light (EBL). Knowledge of the EBL is important to understand the nature of star formation and galaxy evolution, but direct measurements of the EBL are limited by galactic and other foreground emissions. In this paper, we report an absorption feature seen in the combined spectra of a sample of gamma-ray blazars out to a redshift of z ~ 1.6. Finally, this feature is caused by attenuation of gamma rays by the EBL at optical to ultraviolet frequencies and allowed us to measure the EBL flux density in this frequency band.

Authors:
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Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE; National Aeronautic and Space Administration (NASA)
Contributing Org.:
Fermi LAT Collaboration
OSTI Identifier:
1356611
Grant/Contract Number:  
AC02-76SF00515
Resource Type:
Accepted Manuscript
Journal Name:
Science
Additional Journal Information:
Journal Volume: 338; Journal Issue: 6111; Journal ID: ISSN 0036-8075
Publisher:
AAAS
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Ackermann, M., Ajello, M., Allafort, A., Schady, P., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Blandford, R. D., Bloom, E. D., Borgland, A. W., Bottacini, E., Bouvier, A., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cavazzuti, E., Cecchi, C., Charles, E., Chaves, R. C. G., Chekhtman, A., Cheung, C. C., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., D'Ammando, F., de Palma, F., Dermer, C. D., Digel, S. W., do Couto e Silva, E., Dominguez, A., Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Fegan, S. J., Focke, W. B., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hays, E., Jackson, M. S., Jogler, T., Kataoka, J., Knodlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Tramacere, A., Nuss, E., Greiner, J., Ohno, M., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Perkins, J. S., Pesce-Rollins, M., Piron, F., Pivato, G., Porter, T. A., Raino, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reyes, L. C., Ritz, S., Rau, A., Romoli, C., Roth, M., Sanchez-Conde, M., Sanchez, D. A., Scargle, J. D., Sgro, C., Siskind, E. J., Spandre, G., Spinelli, P., Stawarz, L., Suson, D. J., Takahashi, H., Tanaka, T., Thayer, J. G., Thompson, D. J., Tibaldo, L., 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., and Wood, M. The Imprint of the Extragalactic Background Light in the Gamma-Ray Spectra of Blazars. United States: N. p., 2012. Web. doi:10.1126/science.1227160.
Ackermann, M., Ajello, M., Allafort, A., Schady, P., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Blandford, R. D., Bloom, E. D., Borgland, A. W., Bottacini, E., Bouvier, A., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cavazzuti, E., Cecchi, C., Charles, E., Chaves, R. C. G., Chekhtman, A., Cheung, C. C., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., D'Ammando, F., de Palma, F., Dermer, C. D., Digel, S. W., do Couto e Silva, E., Dominguez, A., Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Fegan, S. J., Focke, W. B., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hays, E., Jackson, M. S., Jogler, T., Kataoka, J., Knodlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Tramacere, A., Nuss, E., Greiner, J., Ohno, M., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Perkins, J. S., Pesce-Rollins, M., Piron, F., Pivato, G., Porter, T. A., Raino, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reyes, L. C., Ritz, S., Rau, A., Romoli, C., Roth, M., Sanchez-Conde, M., Sanchez, D. A., Scargle, J. D., Sgro, C., Siskind, E. J., Spandre, G., Spinelli, P., Stawarz, L., Suson, D. J., Takahashi, H., Tanaka, T., Thayer, J. G., Thompson, D. J., Tibaldo, L., 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., & Wood, M. The Imprint of the Extragalactic Background Light in the Gamma-Ray Spectra of Blazars. United States. doi:10.1126/science.1227160.
Ackermann, M., Ajello, M., Allafort, A., Schady, P., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Blandford, R. D., Bloom, E. D., Borgland, A. W., Bottacini, E., Bouvier, A., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cavazzuti, E., Cecchi, C., Charles, E., Chaves, R. C. G., Chekhtman, A., Cheung, C. C., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., D'Ammando, F., de Palma, F., Dermer, C. D., Digel, S. W., do Couto e Silva, E., Dominguez, A., Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Fegan, S. J., Focke, W. B., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hays, E., Jackson, M. S., Jogler, T., Kataoka, J., Knodlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Tramacere, A., Nuss, E., Greiner, J., Ohno, M., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Perkins, J. S., Pesce-Rollins, M., Piron, F., Pivato, G., Porter, T. A., Raino, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reyes, L. C., Ritz, S., Rau, A., Romoli, C., Roth, M., Sanchez-Conde, M., Sanchez, D. A., Scargle, J. D., Sgro, C., Siskind, E. J., Spandre, G., Spinelli, P., Stawarz, L., Suson, D. J., Takahashi, H., Tanaka, T., Thayer, J. G., Thompson, D. J., Tibaldo, L., 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., and Wood, M. Fri . "The Imprint of the Extragalactic Background Light in the Gamma-Ray Spectra of Blazars". United States. doi:10.1126/science.1227160. https://www.osti.gov/servlets/purl/1356611.
@article{osti_1356611,
title = {The Imprint of the Extragalactic Background Light in the Gamma-Ray Spectra of Blazars},
author = {Ackermann, M. and Ajello, M. and Allafort, A. and Schady, P. and Baldini, L. and Ballet, J. and Barbiellini, G. and Bastieri, D. and Bellazzini, R. and Blandford, R. D. and Bloom, E. D. and Borgland, A. W. and Bottacini, E. and Bouvier, A. and Bregeon, J. and Brigida, M. and Bruel, P. and Buehler, R. and Buson, S. and Caliandro, G. A. and Cameron, R. A. and Caraveo, P. A. and Cavazzuti, E. and Cecchi, C. and Charles, E. and Chaves, R. C. G. and Chekhtman, A. and Cheung, C. C. and Chiang, J. and Chiaro, G. and Ciprini, S. and Claus, R. and Cohen-Tanugi, J. and Conrad, J. and Cutini, S. and D'Ammando, F. and de Palma, F. and Dermer, C. D. and Digel, S. W. and do Couto e Silva, E. and Dominguez, A. and Drell, P. S. and Drlica-Wagner, A. and Favuzzi, C. and Fegan, S. J. and Focke, W. B. and Franckowiak, A. and Fukazawa, Y. and Funk, S. and Fusco, P. and Gargano, F. and Gasparrini, D. and Gehrels, N. and Germani, S. and Giglietto, N. and Giordano, F. and Giroletti, M. and Glanzman, T. and Godfrey, G. and Grenier, I. A. and Grove, J. E. and Guiriec, S. and Gustafsson, M. and Hadasch, D. and Hayashida, M. and Hays, E. and Jackson, M. S. and Jogler, T. and Kataoka, J. and Knodlseder, J. and Kuss, M. and Lande, J. and Larsson, S. and Latronico, L. and Longo, F. and Loparco, F. and Lovellette, M. N. and Lubrano, P. and Mazziotta, M. N. and McEnery, J. E. and Mehault, J. and Michelson, P. F. and Mizuno, T. and Monte, C. and Monzani, M. E. and Morselli, A. and Moskalenko, I. V. and Murgia, S. and Tramacere, A. and Nuss, E. and Greiner, J. and Ohno, M. and Ohsugi, T. and Omodei, N. and Orienti, M. and Orlando, E. and Ormes, J. F. and Paneque, D. and Perkins, J. S. and Pesce-Rollins, M. and Piron, F. and Pivato, G. and Porter, T. A. and Raino, S. and Rando, R. and Razzano, M. and Razzaque, S. and Reimer, A. and Reimer, O. and Reyes, L. C. and Ritz, S. and Rau, A. and Romoli, C. and Roth, M. and Sanchez-Conde, M. and Sanchez, D. A. and Scargle, J. D. and Sgro, C. and Siskind, E. J. and Spandre, G. and Spinelli, P. and Stawarz, L. and Suson, D. J. and Takahashi, H. and Tanaka, T. and Thayer, J. G. and Thompson, D. J. and Tibaldo, L. and Tinivella, M. and Torres, D. F. and Tosti, G. and Troja, E. and Usher, T. L. and Vandenbroucke, J. and Vasileiou, V. and Vianello, G. and Vitale, V. and Waite, A. P. and Winer, B. L. and Wood, K. S. and Wood, M.},
abstractNote = {The light emitted by stars and accreting compact objects through the history of the universe is encoded in the intensity of the extragalactic background light (EBL). Knowledge of the EBL is important to understand the nature of star formation and galaxy evolution, but direct measurements of the EBL are limited by galactic and other foreground emissions. In this paper, we report an absorption feature seen in the combined spectra of a sample of gamma-ray blazars out to a redshift of z ~ 1.6. Finally, this feature is caused by attenuation of gamma rays by the EBL at optical to ultraviolet frequencies and allowed us to measure the EBL flux density in this frequency band.},
doi = {10.1126/science.1227160},
journal = {Science},
number = 6111,
volume = 338,
place = {United States},
year = {2012},
month = {11}
}

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    PSR J2021+4026 IN THE GAMMA CYGNI REGION: THE FIRST VARIABLE γ-RAY PULSAR SEEN BY THE Fermi LAT
    journal, October 2013


    Exploring the multiband emission of TXS 0536+145: the most distant γ-ray flaring blazar
    journal, September 2014

    • Orienti, M.; D'Ammando, F.; Giroletti, M.
    • Monthly Notices of the Royal Astronomical Society, Vol. 444, Issue 4
    • DOI: 10.1093/mnras/stu1644

    Probing the very high energy γ-ray spectral curvature in the blazar PG 1553+113 with the MAGIC telescopes
    journal, May 2015

    • Aleksić, J.; Ansoldi, S.; Antonelli, L. A.
    • Monthly Notices of the Royal Astronomical Society, Vol. 450, Issue 4
    • DOI: 10.1093/mnras/stv811

    Measurement of the extragalactic background light using MAGIC and Fermi-LAT gamma-ray observations of blazars up to z = 1
    journal, April 2019

    • Acciari, V. A.; Ansoldi, S.; Antonelli, L. A.
    • Monthly Notices of the Royal Astronomical Society, Vol. 486, Issue 3
    • DOI: 10.1093/mnras/stz943

    Extragalactic background light measurements and applications
    journal, March 2016


    Gamma-Rays from Blazars and the Extragalactic Background Light
    journal, October 2013