Gamma-ray flares from the Crab Nebula

A. A. Abdo, M. Ackermann, M. Ajello, A. Allafort, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, K. Bechtol, R. Bellazzini, B. Berenji, R. D. Blandford, E. D. Bloom, E. Bonamente, A. W. Borgland, A. Bouvier, T. J. Brandt, J. Bregeon, A. Brez, M. BrigidaP. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, A. Cannon, P. A. Caraveo, J. M. Casandjian, Ö Çelik, E. Charles, A. Chekhtman, C. C. Cheung, J. Chiang, S. Ciprini, R. Claus, J. Cohen-Tanugi, L. Costamante, S. Cutini, F. D'Ammando, C. D. Dermer, A. De Angelis, A. De Luca, F. De Palma, S. W. Digel, E. Do Couto E Silva, P. S. Drell, A. Drlica-Wagner, R. Dubois, D. Dumora, C. Favuzzi, S. J. Fegan, E. C. Ferrara, W. B. Focke, P. Fortin, M. Frailis, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Gehrels, S. Germani, N. Giglietto, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, I. A. Grenier, M. H. Grondin, J. E. Grove, S. Guiriec, D. Hadasch, Y. Hanabata, A. K. Harding, K. Hayashi, M. Hayashida, E. Hays, D. Horan, R. Itoh, G. Jóhannesson, A. S. Johnson, T. J. Johnson, D. Khangulyan, T. Kamae, H. Katagiri, Jun Kataoka, M. Kerr, J. Knödlseder, M. Kuss, J. Lande, L. Latronico, S. H. Lee, M. Lemoine-Goumard, F. Longo, F. Loparco, P. Lubrano, G. M. Madejski, A. Makeev, M. Marelli, M. N. Mazziotta, J. E. McEnery, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, C. Monte, M. E. Monzani, A. Morselli, I. V. Moskalenko, S. Murgia, T. Nakamori, M. Naumann-Godo, P. L. Nolan, J. P. Norris, E. Nuss, T. Ohsugi, A. Okumura, N. Omodei, J. F. Ormes, M. Ozaki, D. Paneque, D. Parent, V. Pelassa, M. Pepe, M. Pesce-Rollins, M. Pierbattista, F. Piron, T. A. Porter, S. Rainò, R. Rando, P. S. Ray, M. Razzano, A. Reimer, O. Reimer, T. Reposeur, S. Ritz, R. W. Romani, H. F W Sadrozinski, D. Sanchez, P. M. Saz Parkinson, J. D. Scargle, T. L. Schalk, C. Sgrò, E. J. Siskind, P. D. Smith, G. Spandre, P. Spinelli, M. S. Strickman, D. J. Suson, H. Takahashi, T. Takahashi, T. Tanaka, J. B. Thayer, D. J. Thompson, L. Tibaldo, D. F. Torres, G. Tosti, A. Tramacere, E. Troja, Y. Uchiyama, J. Vandenbroucke, V. Vasileiou, G. Vianello, V. Vitale, P. Wang, K. S. Wood, Z. Yang, M. Ziegler

    Research output: Contribution to journalArticle

    259 Citations (Scopus)

    Abstract

    A young and energetic pulsar powers the well-known Crab Nebula. Here, we describe two separate gamma-ray (photon energy greater than 100 mega-electron volts) flares from this source detected by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. The first flare occurred in February 2009 and lasted approximately 16 days. The second flare was detected in September 2010 and lasted approximately 4 days. During these outbursts, the gamma-ray flux from the nebula increased by factors of four and six, respectively. The brevity of the flares implies that the gamma rays were emitted via synchrotron radiation from peta-electron-volt (1015 electron volts) electrons in a region smaller than 1.4 × 10-2 parsecs. These are the highest-energy particles that can be associated with a discrete astronomical source, and they pose challenges to particle acceleration theory.

    Original languageEnglish
    Pages (from-to)739-742
    Number of pages4
    JournalScience
    Volume331
    Issue number6018
    DOIs
    Publication statusPublished - 2011 Feb 11

    Fingerprint

    Gamma Rays
    Electrons
    Telescopes
    Synchrotrons
    Photons
    Radiation

    ASJC Scopus subject areas

    • General

    Cite this

    Abdo, A. A., Ackermann, M., Ajello, M., Allafort, A., Baldini, L., Ballet, J., ... Ziegler, M. (2011). Gamma-ray flares from the Crab Nebula. Science, 331(6018), 739-742. https://doi.org/10.1126/science.1199705

    Gamma-ray flares from the Crab Nebula. / Abdo, A. A.; Ackermann, M.; Ajello, M.; Allafort, A.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Bonamente, E.; Borgland, A. W.; Bouvier, A.; Brandt, T. J.; Bregeon, J.; Brez, A.; Brigida, M.; Bruel, P.; Buehler, R.; Buson, S.; Caliandro, G. A.; Cameron, R. A.; Cannon, A.; Caraveo, P. A.; Casandjian, J. M.; Çelik, Ö; Charles, E.; Chekhtman, A.; Cheung, C. C.; Chiang, J.; Ciprini, S.; Claus, R.; Cohen-Tanugi, J.; Costamante, L.; Cutini, S.; D'Ammando, F.; Dermer, C. D.; De Angelis, A.; De Luca, A.; De Palma, F.; Digel, S. W.; Do Couto E Silva, E.; Drell, P. S.; Drlica-Wagner, A.; Dubois, R.; Dumora, D.; Favuzzi, C.; Fegan, S. J.; Ferrara, E. C.; Focke, W. B.; Fortin, P.; Frailis, M.; 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.; Grondin, M. H.; Grove, J. E.; Guiriec, S.; Hadasch, D.; Hanabata, Y.; Harding, A. K.; Hayashi, K.; Hayashida, M.; Hays, E.; Horan, D.; Itoh, R.; Jóhannesson, G.; Johnson, A. S.; Johnson, T. J.; Khangulyan, D.; Kamae, T.; Katagiri, H.; Kataoka, Jun; Kerr, M.; Knödlseder, J.; Kuss, M.; Lande, J.; Latronico, L.; Lee, S. H.; Lemoine-Goumard, M.; Longo, F.; Loparco, F.; Lubrano, P.; Madejski, G. M.; Makeev, A.; Marelli, M.; Mazziotta, M. N.; McEnery, J. E.; Michelson, P. F.; Mitthumsiri, W.; Mizuno, T.; Moiseev, A. A.; Monte, C.; Monzani, M. E.; Morselli, A.; Moskalenko, I. V.; Murgia, S.; Nakamori, T.; Naumann-Godo, M.; Nolan, P. L.; Norris, J. P.; Nuss, E.; Ohsugi, T.; Okumura, A.; Omodei, N.; Ormes, J. F.; Ozaki, M.; Paneque, D.; Parent, D.; Pelassa, V.; Pepe, M.; Pesce-Rollins, M.; Pierbattista, M.; Piron, F.; Porter, T. A.; Rainò, S.; Rando, R.; Ray, P. S.; Razzano, M.; Reimer, A.; Reimer, O.; Reposeur, T.; Ritz, S.; Romani, R. W.; Sadrozinski, H. F W; Sanchez, D.; Saz Parkinson, P. M.; Scargle, J. D.; Schalk, T. L.; Sgrò, C.; Siskind, E. J.; Smith, P. D.; Spandre, G.; Spinelli, P.; Strickman, M. S.; Suson, D. J.; Takahashi, H.; Takahashi, T.; Tanaka, T.; Thayer, J. B.; Thompson, D. J.; Tibaldo, L.; Torres, D. F.; Tosti, G.; Tramacere, A.; Troja, E.; Uchiyama, Y.; Vandenbroucke, J.; Vasileiou, V.; Vianello, G.; Vitale, V.; Wang, P.; Wood, K. S.; Yang, Z.; Ziegler, M.

    In: Science, Vol. 331, No. 6018, 11.02.2011, p. 739-742.

    Research output: Contribution to journalArticle

    Abdo, AA, Ackermann, M, Ajello, M, Allafort, A, Baldini, L, Ballet, J, Barbiellini, G, Bastieri, D, Bechtol, K, Bellazzini, R, Berenji, B, Blandford, RD, Bloom, ED, Bonamente, E, Borgland, AW, Bouvier, A, Brandt, TJ, Bregeon, J, Brez, A, Brigida, M, Bruel, P, Buehler, R, Buson, S, Caliandro, GA, Cameron, RA, Cannon, A, Caraveo, PA, Casandjian, JM, Çelik, Ö, Charles, E, Chekhtman, A, Cheung, CC, Chiang, J, Ciprini, S, Claus, R, Cohen-Tanugi, J, Costamante, L, Cutini, S, D'Ammando, F, Dermer, CD, De Angelis, A, De Luca, A, De Palma, F, Digel, SW, Do Couto E Silva, E, Drell, PS, Drlica-Wagner, A, Dubois, R, Dumora, D, Favuzzi, C, Fegan, SJ, Ferrara, EC, Focke, WB, Fortin, P, Frailis, M, 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, IA, Grondin, MH, Grove, JE, Guiriec, S, Hadasch, D, Hanabata, Y, Harding, AK, Hayashi, K, Hayashida, M, Hays, E, Horan, D, Itoh, R, Jóhannesson, G, Johnson, AS, Johnson, TJ, Khangulyan, D, Kamae, T, Katagiri, H, Kataoka, J, Kerr, M, Knödlseder, J, Kuss, M, Lande, J, Latronico, L, Lee, SH, Lemoine-Goumard, M, Longo, F, Loparco, F, Lubrano, P, Madejski, GM, Makeev, A, Marelli, M, Mazziotta, MN, McEnery, JE, Michelson, PF, Mitthumsiri, W, Mizuno, T, Moiseev, AA, Monte, C, Monzani, ME, Morselli, A, Moskalenko, IV, Murgia, S, Nakamori, T, Naumann-Godo, M, Nolan, PL, Norris, JP, Nuss, E, Ohsugi, T, Okumura, A, Omodei, N, Ormes, JF, Ozaki, M, Paneque, D, Parent, D, Pelassa, V, Pepe, M, Pesce-Rollins, M, Pierbattista, M, Piron, F, Porter, TA, Rainò, S, Rando, R, Ray, PS, Razzano, M, Reimer, A, Reimer, O, Reposeur, T, Ritz, S, Romani, RW, Sadrozinski, HFW, Sanchez, D, Saz Parkinson, PM, Scargle, JD, Schalk, TL, Sgrò, C, Siskind, EJ, Smith, PD, Spandre, G, Spinelli, P, Strickman, MS, Suson, DJ, Takahashi, H, Takahashi, T, Tanaka, T, Thayer, JB, Thompson, DJ, Tibaldo, L, Torres, DF, Tosti, G, Tramacere, A, Troja, E, Uchiyama, Y, Vandenbroucke, J, Vasileiou, V, Vianello, G, Vitale, V, Wang, P, Wood, KS, Yang, Z & Ziegler, M 2011, 'Gamma-ray flares from the Crab Nebula', Science, vol. 331, no. 6018, pp. 739-742. https://doi.org/10.1126/science.1199705
    Abdo AA, Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J et al. Gamma-ray flares from the Crab Nebula. Science. 2011 Feb 11;331(6018):739-742. https://doi.org/10.1126/science.1199705
    Abdo, A. A. ; Ackermann, M. ; Ajello, M. ; Allafort, A. ; Baldini, L. ; Ballet, J. ; Barbiellini, G. ; Bastieri, D. ; Bechtol, K. ; Bellazzini, R. ; Berenji, B. ; Blandford, R. D. ; Bloom, E. D. ; Bonamente, E. ; Borgland, A. W. ; Bouvier, A. ; Brandt, T. J. ; Bregeon, J. ; Brez, A. ; Brigida, M. ; Bruel, P. ; Buehler, R. ; Buson, S. ; Caliandro, G. A. ; Cameron, R. A. ; Cannon, A. ; Caraveo, P. A. ; Casandjian, J. M. ; Çelik, Ö ; Charles, E. ; Chekhtman, A. ; Cheung, C. C. ; Chiang, J. ; Ciprini, S. ; Claus, R. ; Cohen-Tanugi, J. ; Costamante, L. ; Cutini, S. ; D'Ammando, F. ; Dermer, C. D. ; De Angelis, A. ; De Luca, A. ; De Palma, F. ; Digel, S. W. ; Do Couto E Silva, E. ; Drell, P. S. ; Drlica-Wagner, A. ; Dubois, R. ; Dumora, D. ; Favuzzi, C. ; Fegan, S. J. ; Ferrara, E. C. ; Focke, W. B. ; Fortin, P. ; Frailis, M. ; 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. ; Grondin, M. H. ; Grove, J. E. ; Guiriec, S. ; Hadasch, D. ; Hanabata, Y. ; Harding, A. K. ; Hayashi, K. ; Hayashida, M. ; Hays, E. ; Horan, D. ; Itoh, R. ; Jóhannesson, G. ; Johnson, A. S. ; Johnson, T. J. ; Khangulyan, D. ; Kamae, T. ; Katagiri, H. ; Kataoka, Jun ; Kerr, M. ; Knödlseder, J. ; Kuss, M. ; Lande, J. ; Latronico, L. ; Lee, S. H. ; Lemoine-Goumard, M. ; Longo, F. ; Loparco, F. ; Lubrano, P. ; Madejski, G. M. ; Makeev, A. ; Marelli, M. ; Mazziotta, M. N. ; McEnery, J. E. ; Michelson, P. F. ; Mitthumsiri, W. ; Mizuno, T. ; Moiseev, A. A. ; Monte, C. ; Monzani, M. E. ; Morselli, A. ; Moskalenko, I. V. ; Murgia, S. ; Nakamori, T. ; Naumann-Godo, M. ; Nolan, P. L. ; Norris, J. P. ; Nuss, E. ; Ohsugi, T. ; Okumura, A. ; Omodei, N. ; Ormes, J. F. ; Ozaki, M. ; Paneque, D. ; Parent, D. ; Pelassa, V. ; Pepe, M. ; Pesce-Rollins, M. ; Pierbattista, M. ; Piron, F. ; Porter, T. A. ; Rainò, S. ; Rando, R. ; Ray, P. S. ; Razzano, M. ; Reimer, A. ; Reimer, O. ; Reposeur, T. ; Ritz, S. ; Romani, R. W. ; Sadrozinski, H. F W ; Sanchez, D. ; Saz Parkinson, P. M. ; Scargle, J. D. ; Schalk, T. L. ; Sgrò, C. ; Siskind, E. J. ; Smith, P. D. ; Spandre, G. ; Spinelli, P. ; Strickman, M. S. ; Suson, D. J. ; Takahashi, H. ; Takahashi, T. ; Tanaka, T. ; Thayer, J. B. ; Thompson, D. J. ; Tibaldo, L. ; Torres, D. F. ; Tosti, G. ; Tramacere, A. ; Troja, E. ; Uchiyama, Y. ; Vandenbroucke, J. ; Vasileiou, V. ; Vianello, G. ; Vitale, V. ; Wang, P. ; Wood, K. S. ; Yang, Z. ; Ziegler, M. / Gamma-ray flares from the Crab Nebula. In: Science. 2011 ; Vol. 331, No. 6018. pp. 739-742.
    @article{34604f622e09434ead252a2aa8577311,
    title = "Gamma-ray flares from the Crab Nebula",
    abstract = "A young and energetic pulsar powers the well-known Crab Nebula. Here, we describe two separate gamma-ray (photon energy greater than 100 mega-electron volts) flares from this source detected by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. The first flare occurred in February 2009 and lasted approximately 16 days. The second flare was detected in September 2010 and lasted approximately 4 days. During these outbursts, the gamma-ray flux from the nebula increased by factors of four and six, respectively. The brevity of the flares implies that the gamma rays were emitted via synchrotron radiation from peta-electron-volt (1015 electron volts) electrons in a region smaller than 1.4 × 10-2 parsecs. These are the highest-energy particles that can be associated with a discrete astronomical source, and they pose challenges to particle acceleration theory.",
    author = "Abdo, {A. A.} and M. Ackermann and M. Ajello and A. Allafort and L. Baldini and J. Ballet and G. Barbiellini and D. Bastieri and K. Bechtol and R. Bellazzini and B. Berenji and Blandford, {R. D.} and Bloom, {E. D.} and E. Bonamente and Borgland, {A. W.} and A. Bouvier and Brandt, {T. J.} and J. Bregeon and A. Brez and M. Brigida and P. Bruel and R. Buehler and S. Buson and Caliandro, {G. A.} and Cameron, {R. A.} and A. Cannon and Caraveo, {P. A.} and Casandjian, {J. M.} and {\"O} {\cC}elik and E. Charles and A. Chekhtman and Cheung, {C. C.} and J. Chiang and S. Ciprini and R. Claus and J. Cohen-Tanugi and L. Costamante and S. Cutini and F. D'Ammando and Dermer, {C. D.} and {De Angelis}, A. and {De Luca}, A. and {De Palma}, F. and Digel, {S. W.} and {Do Couto E Silva}, E. and Drell, {P. S.} and A. Drlica-Wagner and R. Dubois and D. Dumora and C. Favuzzi and Fegan, {S. J.} and Ferrara, {E. C.} and Focke, {W. B.} and P. Fortin and M. Frailis and Y. Fukazawa and S. Funk and P. Fusco and F. Gargano and D. Gasparrini and N. Gehrels and S. Germani and N. Giglietto and F. Giordano and M. Giroletti and T. Glanzman and G. Godfrey and Grenier, {I. A.} and Grondin, {M. H.} and Grove, {J. E.} and S. Guiriec and D. Hadasch and Y. Hanabata and Harding, {A. K.} and K. Hayashi and M. Hayashida and E. Hays and D. Horan and R. Itoh and G. J{\'o}hannesson and Johnson, {A. S.} and Johnson, {T. J.} and D. Khangulyan and T. Kamae and H. Katagiri and Jun Kataoka and M. Kerr and J. Kn{\"o}dlseder and M. Kuss and J. Lande and L. Latronico and Lee, {S. H.} and M. Lemoine-Goumard and F. Longo and F. Loparco and P. Lubrano and Madejski, {G. M.} and A. Makeev and M. Marelli and Mazziotta, {M. N.} and McEnery, {J. E.} and Michelson, {P. F.} and W. Mitthumsiri and T. Mizuno and Moiseev, {A. A.} and C. Monte and Monzani, {M. E.} and A. Morselli and Moskalenko, {I. V.} and S. Murgia and T. Nakamori and M. Naumann-Godo and Nolan, {P. L.} and Norris, {J. P.} and E. Nuss and T. Ohsugi and A. Okumura and N. Omodei and Ormes, {J. F.} and M. Ozaki and D. Paneque and D. Parent and V. Pelassa and M. Pepe and M. Pesce-Rollins and M. Pierbattista and F. Piron and Porter, {T. A.} and S. Rain{\`o} and R. Rando and Ray, {P. S.} and M. Razzano and A. Reimer and O. Reimer and T. Reposeur and S. Ritz and Romani, {R. W.} and Sadrozinski, {H. F W} and D. Sanchez and {Saz Parkinson}, {P. M.} and Scargle, {J. D.} and Schalk, {T. L.} and C. Sgr{\`o} and Siskind, {E. J.} and Smith, {P. D.} and G. Spandre and P. Spinelli and Strickman, {M. S.} and Suson, {D. J.} and H. Takahashi and T. Takahashi and T. Tanaka and Thayer, {J. B.} and Thompson, {D. J.} and L. Tibaldo and Torres, {D. F.} and G. Tosti and A. Tramacere and E. Troja and Y. Uchiyama and J. Vandenbroucke and V. Vasileiou and G. Vianello and V. Vitale and P. Wang and Wood, {K. S.} and Z. Yang and M. Ziegler",
    year = "2011",
    month = "2",
    day = "11",
    doi = "10.1126/science.1199705",
    language = "English",
    volume = "331",
    pages = "739--742",
    journal = "Science",
    issn = "0036-8075",
    publisher = "American Association for the Advancement of Science",
    number = "6018",

    }

    TY - JOUR

    T1 - Gamma-ray flares from the Crab Nebula

    AU - Abdo, A. A.

    AU - Ackermann, M.

    AU - Ajello, M.

    AU - Allafort, A.

    AU - Baldini, L.

    AU - Ballet, J.

    AU - Barbiellini, G.

    AU - Bastieri, D.

    AU - Bechtol, K.

    AU - Bellazzini, R.

    AU - Berenji, B.

    AU - Blandford, R. D.

    AU - Bloom, E. D.

    AU - Bonamente, E.

    AU - Borgland, A. W.

    AU - Bouvier, A.

    AU - Brandt, T. J.

    AU - Bregeon, J.

    AU - Brez, A.

    AU - Brigida, M.

    AU - Bruel, P.

    AU - Buehler, R.

    AU - Buson, S.

    AU - Caliandro, G. A.

    AU - Cameron, R. A.

    AU - Cannon, A.

    AU - Caraveo, P. A.

    AU - Casandjian, J. M.

    AU - Çelik, Ö

    AU - Charles, E.

    AU - Chekhtman, A.

    AU - Cheung, C. C.

    AU - Chiang, J.

    AU - Ciprini, S.

    AU - Claus, R.

    AU - Cohen-Tanugi, J.

    AU - Costamante, L.

    AU - Cutini, S.

    AU - D'Ammando, F.

    AU - Dermer, C. D.

    AU - De Angelis, A.

    AU - De Luca, A.

    AU - De Palma, F.

    AU - Digel, S. W.

    AU - Do Couto E Silva, E.

    AU - Drell, P. S.

    AU - Drlica-Wagner, A.

    AU - Dubois, R.

    AU - Dumora, D.

    AU - Favuzzi, C.

    AU - Fegan, S. J.

    AU - Ferrara, E. C.

    AU - Focke, W. B.

    AU - Fortin, P.

    AU - Frailis, M.

    AU - Fukazawa, Y.

    AU - Funk, S.

    AU - Fusco, P.

    AU - Gargano, F.

    AU - Gasparrini, D.

    AU - Gehrels, N.

    AU - Germani, S.

    AU - Giglietto, N.

    AU - Giordano, F.

    AU - Giroletti, M.

    AU - Glanzman, T.

    AU - Godfrey, G.

    AU - Grenier, I. A.

    AU - Grondin, M. H.

    AU - Grove, J. E.

    AU - Guiriec, S.

    AU - Hadasch, D.

    AU - Hanabata, Y.

    AU - Harding, A. K.

    AU - Hayashi, K.

    AU - Hayashida, M.

    AU - Hays, E.

    AU - Horan, D.

    AU - Itoh, R.

    AU - Jóhannesson, G.

    AU - Johnson, A. S.

    AU - Johnson, T. J.

    AU - Khangulyan, D.

    AU - Kamae, T.

    AU - Katagiri, H.

    AU - Kataoka, Jun

    AU - Kerr, M.

    AU - Knödlseder, J.

    AU - Kuss, M.

    AU - Lande, J.

    AU - Latronico, L.

    AU - Lee, S. H.

    AU - Lemoine-Goumard, M.

    AU - Longo, F.

    AU - Loparco, F.

    AU - Lubrano, P.

    AU - Madejski, G. M.

    AU - Makeev, A.

    AU - Marelli, M.

    AU - Mazziotta, M. N.

    AU - McEnery, J. E.

    AU - Michelson, P. F.

    AU - Mitthumsiri, W.

    AU - Mizuno, T.

    AU - Moiseev, A. A.

    AU - Monte, C.

    AU - Monzani, M. E.

    AU - Morselli, A.

    AU - Moskalenko, I. V.

    AU - Murgia, S.

    AU - Nakamori, T.

    AU - Naumann-Godo, M.

    AU - Nolan, P. L.

    AU - Norris, J. P.

    AU - Nuss, E.

    AU - Ohsugi, T.

    AU - Okumura, A.

    AU - Omodei, N.

    AU - Ormes, J. F.

    AU - Ozaki, M.

    AU - Paneque, D.

    AU - Parent, D.

    AU - Pelassa, V.

    AU - Pepe, M.

    AU - Pesce-Rollins, M.

    AU - Pierbattista, M.

    AU - Piron, F.

    AU - Porter, T. A.

    AU - Rainò, S.

    AU - Rando, R.

    AU - Ray, P. S.

    AU - Razzano, M.

    AU - Reimer, A.

    AU - Reimer, O.

    AU - Reposeur, T.

    AU - Ritz, S.

    AU - Romani, R. W.

    AU - Sadrozinski, H. F W

    AU - Sanchez, D.

    AU - Saz Parkinson, P. M.

    AU - Scargle, J. D.

    AU - Schalk, T. L.

    AU - Sgrò, C.

    AU - Siskind, E. J.

    AU - Smith, P. D.

    AU - Spandre, G.

    AU - Spinelli, P.

    AU - Strickman, M. S.

    AU - Suson, D. J.

    AU - Takahashi, H.

    AU - Takahashi, T.

    AU - Tanaka, T.

    AU - Thayer, J. B.

    AU - Thompson, D. J.

    AU - Tibaldo, L.

    AU - Torres, D. F.

    AU - Tosti, G.

    AU - Tramacere, A.

    AU - Troja, E.

    AU - Uchiyama, Y.

    AU - Vandenbroucke, J.

    AU - Vasileiou, V.

    AU - Vianello, G.

    AU - Vitale, V.

    AU - Wang, P.

    AU - Wood, K. S.

    AU - Yang, Z.

    AU - Ziegler, M.

    PY - 2011/2/11

    Y1 - 2011/2/11

    N2 - A young and energetic pulsar powers the well-known Crab Nebula. Here, we describe two separate gamma-ray (photon energy greater than 100 mega-electron volts) flares from this source detected by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. The first flare occurred in February 2009 and lasted approximately 16 days. The second flare was detected in September 2010 and lasted approximately 4 days. During these outbursts, the gamma-ray flux from the nebula increased by factors of four and six, respectively. The brevity of the flares implies that the gamma rays were emitted via synchrotron radiation from peta-electron-volt (1015 electron volts) electrons in a region smaller than 1.4 × 10-2 parsecs. These are the highest-energy particles that can be associated with a discrete astronomical source, and they pose challenges to particle acceleration theory.

    AB - A young and energetic pulsar powers the well-known Crab Nebula. Here, we describe two separate gamma-ray (photon energy greater than 100 mega-electron volts) flares from this source detected by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. The first flare occurred in February 2009 and lasted approximately 16 days. The second flare was detected in September 2010 and lasted approximately 4 days. During these outbursts, the gamma-ray flux from the nebula increased by factors of four and six, respectively. The brevity of the flares implies that the gamma rays were emitted via synchrotron radiation from peta-electron-volt (1015 electron volts) electrons in a region smaller than 1.4 × 10-2 parsecs. These are the highest-energy particles that can be associated with a discrete astronomical source, and they pose challenges to particle acceleration theory.

    UR - http://www.scopus.com/inward/record.url?scp=79951556096&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=79951556096&partnerID=8YFLogxK

    U2 - 10.1126/science.1199705

    DO - 10.1126/science.1199705

    M3 - Article

    C2 - 21212321

    AN - SCOPUS:79951556096

    VL - 331

    SP - 739

    EP - 742

    JO - Science

    JF - Science

    SN - 0036-8075

    IS - 6018

    ER -