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21 results on '"Bignami GF"'

1. Fermi Large Area Telescope Second Source Catalog

Author

Nolan, P. L., Abdo, A. A., Ackermann, M., Ajello, M., Allafort, A., Antolini, E., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Belfiore, A., Bellazzini, R., Berenji, B., Bignami, G. F., Blandford, R. D., Bloom, E. D., Bonamente, E., Bonnell, J., Borgland, A. W., Bottacini, E., Bouvier, A., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Campana, R., Canadas, B., Cannon, A., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Ceccanti, M., Cecchi, C., Celik, O., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Chipaux, R., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cominsky, L. R., Conrad, J., Corbet, R., Cutini, S., D'Ammando, F., Davis, D. S., de, Angelis A., DeCesar, M. E., DeKlotz, M., De, Luca A., den, Hartog P. R., de, Palma F., Dermer, C. D., Digel, S. W., do, Couto e Silva E., Drell, P. S., Drlica-Wagner, A., Dubois, R., Dumora, D., Escande, L., Fabiani, D., Falletti, L., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Fortin, P., Frailis, M., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M.-H., Grove, J. E., Guillemot, L., Guiriec, S., Gustafsson, M., Hadasch, D., Harding, A. K., Hays, E., Hill, A. B., Horan, D., Hou, X., Hughes, R. E., Iafrate, G., Itoh, Ryosuke, Johannesson, G., Johnson, R. P., Johnson, T. E., Johnson, A. S., Johnson, T. J., Kerr, M., Knodlseder, J., Kocevski, D., Kuss, M., Lande, J., Landriu, D., Latronico, L., Lemoine-Goumard, M., Lionetto, A. M., Llena, Garde M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Marelli, M., Massaro, E., Mazziotta, M. N., McConville, W., McEnery, J. E., Mehault, J., Michelson, P. F., Minuti, M., Mitthumsiri, W., Moiseev, A. A., Mongelli, M., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Norris, J. P., Nuss, E., Nymark, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Parent, D., Perkins, J. S., Pesce-Rollins, M., Pierbattista, M., Pinchera, M., Piron, F., Pivato, G., Porter, T. A., Racusin, J. L., Raino, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Romani, R. W., Roth, M., Rousseau, R., Ryde, F., Sadrozinski, H. F.-W., Salvetti, D., Sanchez, D. A., Saz, Parkinson P. M., Sbarra, C., Scargle, J. D., Schalk, T. L., Sgro, C., Shaw, M. S., Shrader, C., Siskind, E. J., Smith, D. A., Spandre, G., Spinelli, P., Stephens, T. E., Strickman, M. S., Suson, D. J., Enoto, Teruaki, Fukazawa, Yasushi, Hanabata, Yoshitaka, Hayashida, Masaaki, Kamae, Tsuneyoshi, Katagiri, Hideaki, Kataoka, Jun, Katsuta, Junichiro, Kawai, Nobuyuki, Mizuno, Tsunefumi, Nakamori, Takeshi, Ohno, Masanori, Ohsugi, Takashi, Okumura, Akira, Ozaki, Masanobu, Tajima, Hiroyasu, Takahashi, Hiromitsu, Takahashi, Tadayuki, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire Univers et Particules de Montpellier (LUPM), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), GLAST, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Fermi-LAT, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Nolan, P. L., Abdo, A. A., Ackermann, M., Ajello, M., Allafort, A., Antolini, E., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Belfiore, A., Bellazzini, R., Berenji, B., Bignami, G. F., Blandford, R. D., Bloom, E. D., Bonamente, E., Bonnell, J., Borgland, A. W., Bottacini, E., Bouvier, A., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Campana, R., Cañadas, B., Cannon, A., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Ceccanti, M., Cecchi, C., Çelik, Ö., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Chipaux, R., Ciprini, S., Claus, R., Cohen Tanugi, J., Cominsky, L. R., Conrad, J., Corbet, R., Cutini, S., D'Ammando, F., Davis, D. S., de Angelis, A., Decesar, M. E., Deklotz, M., De Luca, A., den Hartog, P. R., de Palma, F., Dermer, C. D., Digel, S. W., Silva, E. do Couto e., Drell, P. S., Drlica Wagner, A., Dubois, R., Dumora, D., Enoto, T., Escande, L., Fabiani, D., Falletti, L., 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., Giebels, B., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M. H., Grove, J. E., Guillemot, L., Guiriec, S., Gustafsson, M., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Hill, A. B., Horan, D., Hou, X., Hughes, R. E., Iafrate, G., Itoh, R., Jóhannesson, G., Johnson, R. P., Johnson, T. E., Johnson, A. S., Johnson, T. J., Kamae, T., Katagiri, H., Kataoka, J., Katsuta, J., Kawai, N., Kerr, M., Knödlseder, J., Kocevski, D., Kuss, M., Lande, J., Landriu, D., Latronico, L., Lemoine Goumard, M., Lionetto, A. M., Llena Garde, M., Longo, Francesco, Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Marelli, M., Massaro, E., Mazziotta, M. N., Mcconville, W., Mcenery, J. E., Mehault, J., Michelson, P. F., Minuti, M., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Mongelli, M., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Naumann Godo, M., Norris, J. P., Nuss, E., Nymark, T., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Panetta, J. H., Parent, D., Perkins, J. S., Pesce Rollins, M., Pierbattista, M., Pinchera, M., Piron, F., Pivato, G., Porter, T. A., Racusin, J. L., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Romani, R. W., Roth, M., Rousseau, R., Ryde, F., Sadrozinski, H. F. W., Salvetti, D., Sanchez, D. A., Saz Parkinson, P. M., Sbarra, C., Scargle, J. D., Schalk, T. L., Sgrò, C., Shaw, M. S., Shrader, C., Siskind, E. J., Smith, D. A., Spandre, G., Spinelli, P., Stephens, T. E., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tibolla, O., Tinebra, F., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Vandenbroucke, J., Van Etten, A., Van Klaveren, B., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Wallace, E., Wang, P., Werner, M., Winer, B. L., Wood, D. L., Wood, K. S., Wood, M., Yang, Z., Zimmer, S., Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Nolan, Pl, Abdo, Aa, Ackermann, M, Ajello, M, Allafort, A, Antolini, E, Atwood, Wb, Axelsson, M, Baldini, L, Ballet, J, Barbiellini, G, Bastieri, D, Bechtol, K, Belfiore, A, Bellazzini, R, Berenji, B, Bignami, Gf, Blandford, Rd, Bloom, Ed, Bonamente, E, Bonnell, J, Borgland, Aw, Bottacini, E, Bouvier, A, Brandt, Tj, Bregeon, J, Brigida, M, Bruel, P, Buehler, R, Burnett, Th, Buson, S, Caliandro, Ga, Cameron, Ra, Campana, R, Canadas, B, Cannon, A, Caraveo, Pa, Casandjian, Jm, Cavazzuti, E, Ceccanti, M, Cecchi, C, Celik, O, Charles, E, Chekhtman, A, Cheung, Cc, Chiang, J, Chipaux, R, Ciprini, S, Claus, R, Cohen-Tanugi, J, Cominsky, Lr, Conrad, J, Corbet, R, Cutini, S, Dammando, F, Davis, D, de Angelis, A, Decesar, Me, Deklotz, M, De Luca, A, den Hartog, Pr, de Palma, F, Dermer, Cd, Digel, Sw, Silva, Ede, Drell, P, Drlica-Wagner, A, Dubois, R, Dumora, D, Enoto, T, Escande, L, Fabiani, D, Falletti, L, 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, Giebels, B, Giglietto, N, Giommi, P, Giordano, F, Giroletti, M, Glanzman, T, Godfrey, G, Grenier, Ia, Grondin, Mh, Grove, Je, Guillemot, L, Guiriec, S, Gustafsson, M, Hadasch, D, Hanabata, Y, Harding, Ak, Hayashida, M, Hays, E, Hill, Ab, Horan, D, Hou, X, Hughes, Re, Iafrate, G, Itoh, R, Johannesson, G, Johnson, Rp, Johnson, Te, Johnson, A, Johnson, Tj, Kamae, T, Katagiri, H, Kataoka, J, Katsuta, J, Kawai, N, Kerr, M, Knodlseder, J, Kocevski, D, Kuss, M, Lande, J, Landriu, D, Latronico, L, Lemoine-Goumard, M, Lionetto, Am, Garde, Ml, Longo, F, Loparco, F, Lott, B, Lovellette, Mn, Lubrano, P, Madejski, Gm, Marelli, M, Massaro, E, Mazziotta, Mn, Mcconville, W, Mcenery, Je, Mehault, J, Michelson, Pf, Minuti, M, Mitthumsiri, W, Mizuno, T, Moiseev, Aa, Mongelli, M, Monte, C, Monzani, Me, Morselli, A, Moskalenko, Iv, Murgia, S, Nakamori, T, Naumann-Godo, M, Norris, Jp, Nuss, E, Nymark, T, Ohno, M, Ohsugi, T, Okumura, A, Omodei, N, Orlando, E, Ormes, Jf, Ozaki, M, Paneque, D, Panetta, Jh, Parent, D, Perkins, J, Pesce-Rollins, M, Pierbattista, M, Pinchera, M, Piron, F, Pivato, G, Porter, Ta, Racusin, Jl, Raino, S, Rando, R, Razzano, M, Razzaque, S, Reimer, A, Reimer, O, Reposeur, T, Ritz, S, Rochester, L, Romani, Rw, Roth, M, Rousseau, R, Ryde, F, Sadrozinski, Hfw, Salvetti, D, Sanchez, Da, Parkinson, Pm, Sbarra, C, Scargle, Jd, Schalk, Tl, Sgro, C, Shaw, M, Shrader, C, Siskind, Ej, Smith, Da, Spandre, G, Spinelli, P, Stephens, Te, Strickman, M, Suson, Dj, Tajima, H, Takahashi, H, Takahashi, T, Tanaka, T, Thayer, Jg, Thayer, Jb, Thompson, Dj, Tibaldo, L, Tibolla, O, Tinebra, F, Tinivella, M, Torres, Df, Tosti, G, Troja, E, Uchiyama, Y, Vandenbroucke, J, Van Etten, A, Van Klaveren, B, Vasileiou, V, Vianello, G, Vitale, V, Waite, Ap, Wallace, E, Wang, P, Werner, M, Winer, Bl, Wood, Dl, Wood, K, Wood, M, Yang, Z, and Zimmer, S

Subjects
catalog, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::High Energy Astrophysical Phenomena, catalogs, gamma rays: general, Flux, Astrophysics, 01 natural sciences, astrofisica, law.invention, cataloghi astronomici, Telescope, Spitzer Space Telescope, law, 0103 physical sciences, 010303 astronomy & astrophysics, raggi gamma, Physics, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astronomy, Astronomy and Astrophysics, Catalogs, Gamma rays: general, Gamma-ray astronomy, Light curve, Galaxy, CTA-102, Space and Planetary Science, ddc:520, Astrophysics - High Energy Astrophysical Phenomena, general [gamma rays], Fermi Gamma-ray Space Telescope
Abstract

著者人数: 237名, Accepted: 2012-02-13, 資料番号: SA1004201000

Published
2012
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2. AGILE OBSERVATIONS OF THE 'SOFT' GAMMA-RAY PULSAR PSR B1509-58

Author

A. Argan, Andrea Bulgarelli, Enrico Costa, G. De Paris, F. Perotti, Patrick Weltevrede, Simon Johnston, A. Giuliani, A. Morselli, I. Donnarumma, A. Rappoldi, E. Vallazza, G. Pucella, V. Cocco, Claudio Labanti, A. W. Chen, C. Pittori, T. Froysland, E. Del Monte, A. Pellizzoni, Francesco Lazzarotto, Massimiliano Fiorini, N. D'Amico, S. Sabatini, Y. Evangelista, Francesco Longo, Andrea Possenti, G. Di Cocco, Paolo Lipari, F. Lucarelli, Giovanni F. Bignami, Marco Feroci, L. Salotti, F. Fuschino, Luigi Pacciani, D. Zanello, A. Zambra, S. Vercellone, M. Burgay, V. Vittorini, Filippo D'Ammando, Paolo Soffitta, M. Trifoglio, Massimo Rapisarda, Guido Barbiellini, P. Santolamazza, Maura Pilia, Alessio Trois, Paolo Giommi, I. Lapshov, Paolo Esposito, Fulvio Gianotti, M. Prest, A. De Luca, P. A. Caraveo, M. Galli, Piergiorgio Picozza, F. Verrecchia, G. Piano, Marco Tavani, Martino Marisaldi, Sandro Mereghetti, P. W. Cattaneo, Pilia M, Pellizzoni A, Trois A, Verrecchia F, Esposito P, Weltevrede P, Johnston S, Burgay M, Possenti A, Del Monte E, Fuschino F, Santolamazza P, Chen A, Giuliani A, Caraveo P, Mereghetti S, Tavani M, Argan A, Costa E, D'Amico N, De Luca A, Evangelista Y, Feroci M, Longo F, Marisaldi M, Barbiellini G, Bulgarelli A, Cattaneo PW, Cocco V, DAmmando F, De Paris G, Di Cocco G, Donnarumma I, Fiorini M, Froysland T, Galli M, Gianotti F, Labanti C, Lapshov I, Lazzarotto F, Lipari P, Morselli A, Pacciani L, Perotti F, Piano G, Picozza P, Prest M, Pucella G, Rapisarda M, Rappoldi A, Sabatini S, Soffitta P, Trifoglio M, Vallazza E, Vercellone S, Vittorini V, Zambra A, Zanello D, Pittori C, Lucarelli F, Giommi P, Salotti L, Bignami GF, M., Pilia, A., Pellizzoni, A., Troi, F., Verrecchia, P., Esposito, P., Weltevrede, S., Johnston, M., Burgay, A., Possenti, E. D., Monte, F., Fuschino, P., Santolamazza, A., Chen, A., Giuliani, P., Caraveo, S., Mereghetti, M., Tavani, A., Argan, E., Costa, N., D'Amico, A. D., Luca, Y., Evangelista, M., Feroci, Longo, Francesco, M., Marisaldi, G., Barbiellini, A., Bulgarelli, P. W., Cattaneo, V., Cocco, F., D'Ammando, G. D., Pari, G. D., Cocco, I., Donnarumma, M., Fiorini, T., Froysland, M., Galli, F., Gianotti, C., Labanti, I., Lapshov, F., Lazzarotto, P., Lipari, A., Morselli, L., Pacciani, F., Perotti, G., Piano, P., Picozza, M., Prest, G., Pucella, M., Rapisarda, A., Rappoldi, S., Sabatini, P., Soffitta, M., Trifoglio, E., Vallazza, S., Vercellone, V., Vittorini, A., Zambra, D., Zanello, C., Pittori, F., Lucarelli, P., Giommi, L., Salotti, and G. F., Bignami

Subjects
Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Agile, pulsar, gamma ray, High Energy Gamma-ray Astronomy, AGILE satellite, Pulsar, Astrophysics::High Energy Astrophysical Phenomena, Gamma ray, FOS: Physical sciences, gamma rays: stars – pulsars: general – pulsars: individual (PSR J1513–5908 (B1509–58)) – stars: neutron, Astronomy and Astrophysics, Astrophysics, Light curve, Electromagnetic radiation, Spectral line, Neutron star, Pair production, Space and Planetary Science, Spectral energy distribution, Astrophysics - High Energy Astrophysical Phenomena
Abstract

We present the results of new Agile observations of PSR B1509-58 performed over a period of 2.5 years following the detection obtained with a subset of the present data. The modulation significance of the lightcurve above 30 MeV is at a 5$\sigma$ confidence level and the lightcurve is similar to those found earlier by Comptel up to 30 MeV: a broad asymmetric first peak reaching its maximum 0.39 +/- 0.02 cycles after the radio peak plus a second peak at 0.94 +/- 0.03. The gamma-ray spectral energy distribution of the pulsed flux detected by Comptel and Agile is well described by a power-law (photon index alpha=1.87+/-0.09) with a remarkable cutoff at E_c=81 +/- 20 MeV, representing the softest spectrum observed among gamma-ray pulsars so far. The pulsar luminosity at E > 1 MeV is $L_{\gamma}=4.2^{+0.5}_{-0.2} \times10^{35}$ erg/s, assuming a distance of 5.2 kpc, which implies a spin-down conversion efficiency to gamma-rays of $\sim 0.03$. The unusual soft break in the spectrum of PSR B1509-58 has been interpreted in the framework of polar cap models as a signature of the exotic photon splitting process in the strong magnetic field of this pulsar. In this interpretation our spectrum constrains the magnetic altitude of the emission point(s) at 3 km above the neutron star surface, implying that the attenuation may not be as strong as formerly suggested because pair production can substitute photon splitting in regions of the magnetosphere where the magnetic field becomes too low to sustain photon splitting. In the case of an outer-gap scenario, or the two pole caustic model, better constraints on the geometry of the emission would be needed from the radio band in order to establish whether the conditions required by the models to reproduce Agile lightcurves and spectra match the polarization measurements., Comment: 17 pages, 2 figures, accepted for publication in ApJ

Published
2010

3. Detection of Gamma-Ray Emission from the Vela Pulsar Wind Nebula with AGILE

Author

A. Pellizzoni, M. Galli, A. Giuliani, F. Verrecchia, Francesco Lazzarotto, E. Vallazza, C. Pittori, T. Contessi, N. D'Amico, G. Piano, G. De Paris, A. Argan, Sandro Mereghetti, E. Rossi, E. Scalise, A. Morselli, Arnaud Ferrari, E. Striani, P. Santolamazza, Andrea Bulgarelli, F. Fuschino, I. Lapshov, S. Colafrancesco, L. Salotti, I. Donnarumma, Y. Evangelista, Massimo Rapisarda, G. Di Cocco, A. Possenti, Enrico Costa, S. Sabatini, Alda Rubini, P. W. Cattaneo, G. Pucella, P. Picozza, Marco Tavani, G. Barbiellini, Elena Moretti, Martino Marisaldi, A. Rappoldi, D. Zanello, M. Prest, V. Cocco, M. Mastropietro, F. Perotti, M. Burgay, V. Vittorini, A. W. Chen, Claudio Labanti, A. Zambra, Paolo Lipari, P. Giommi, J. Palfreyman, Giovanni F. Bignami, P. A. Caraveo, M. Trifoglio, M. Fiorini, E. Del Monte, Aidan Hotan, F. Longo, Angelo Antonelli, Marco Feroci, Luigi Pacciani, Maura Pilia, Alessio Trois, Paolo Esposito, Fulvio Gianotti, G. Di Persio, Filippo D'Ammando, Paolo Soffitta, S. Vercellone, Pellizzoni A, Trois A, Tavani M, Pilia M, Giuliani A, Pucella G, Esposito P, Sabatini S, Piano G, Argan A, Barbiellini G, Bulgarelli A, Burgay M, Caraveo P, Cattaneo PW, Chen AW, Cocco V, Contessi T, Costa E, DAmmando F, Del Monte E, De Paris G, Di Cocco G, Di Persio G, Donnarumma I, Evangelista Y, Feroci M, Ferrari A, Fiorini M, Fuschino F, Galli M, Gianotti F, Hotan A, Labanti C, Lapshov I, Lazzarotto F, Lipari P, Longo F, Marisaldi M, Mastropietro M, Mereghetti S, Moretti E, Morselli A, Pacciani L, Palfreyman J, Perotti F, Picozza P, Pittori C, Possenti A, Prest M, Rapisarda M, Rappoldi A, Rossi E, Rubini A, Santolamazza P, Scalise E, Soffitta P, Striani E, Trifoglio M, Vallazza E, Vercellone S, Verrecchia F, Vittorini V, Zambra A, Zanello D, Giommi P, Colafrancesco S, Antonelli A, Salotti L, D'Amico N, Bignami GF, A., Pellizzoni, A., Troi, M., Tavani, M., Pilia, A., Giuliani, G., Pucella, P., Esposito, S., Sabatini, G., Piano, A., Argan, G., Barbiellini, A., Bulgarelli, M., Burgay, P., Caraveo, P. W., Cattaneo, A. W., Chen, V., Cocco, T., Contessi, E., Costa, F., D'Ammando, E. D., Monte, G. D., Pari, G. D., Cocco, G. D., Persio, I., Donnarumma, Y., Evangelista, M., Feroci, A., Ferrari, M., Fiorini, F., Fuschino, M., Galli, F., Gianotti, A., Hotan, C., Labanti, I., Lapshov, F., Lazzarotto, P., Lipari, Longo, Francesco, M., Marisaldi, M., Mastropietro, S., Mereghetti, E., Moretti, A., Morselli, L., Pacciani, J., Palfreyman, F., Perotti, P., Picozza, C., Pittori, A., Possenti, M., Prest, M., Rapisarda, A., Rappoldi, E., Rossi, A., Rubini, P., Santolamazza, E., Scalise, P., Soffitta, E., Striani, M., Trifoglio, E., Vallazza, S., Vercellone, F., Verrecchia, V., Vittorini, A., Zambra, D., Zanello, P., Giommi, S., Colafrancesco, A., Antonelli, L., Salotti, N., D'Amico, and G. F., Bignami

Subjects
Astrophysics::High Energy Astrophysical Phenomena, Population, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Vela, Pulsar wind nebula, High Energy Gamma-ray Astronomy, gamma detection, Relativistic particle, AGILE, Pulsar Wind Nebulae, Pulsar, Astrophysics::Solar and Stellar Astrophysics, AGILE satellite, education, Astrophysics::Galaxy Astrophysics, pulsar, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), education.field_of_study, Multidisciplinary, Vela Pulsar Wind Nebula, AGILE, gamma-rays, Gamma ray, Astronomy, Physics::Space Physics, Astrophysics - High Energy Astrophysical Phenomena, Phenomenology (particle physics), X-ray pulsar
Abstract

Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae (PWNe) are observed in the radio, optical, x-rays and, in some cases, also at TeV energies, but the lack of information in the gamma-ray band prevents from drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission, probing multivavelength PWN models, and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified Galactic gamma-ray sources., Comment: Accepted by Science; first published online on December 31, 2009 in Science Express. Science article and Supporting Online Material are available at http://www.sciencemag.org

Published
2009
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4. A variable absorption feature in the X-ray spectrum of a magnetar.

Author

Tiengo A, Esposito P, Mereghetti S, Turolla R, Nobili L, Gastaldello F, Götz D, Israel GL, Rea N, Stella L, Zane S, and Bignami GF

Abstract

Soft-γ-ray repeaters (SGRs) and anomalous X-ray pulsars (AXPs) are slowly rotating, isolated neutron stars that sporadically undergo episodes of long-term flux enhancement (outbursts) generally accompanied by the emission of short bursts of hard X-rays. This behaviour can be understood in the magnetar model, according to which these sources are mainly powered by their own magnetic energy. This is supported by the fact that the magnetic fields inferred from several observed properties of SGRs and AXPs are greater than-or at the high end of the range of-those of radio pulsars. In the peculiar case of SGR 0418+5729, a weak dipole magnetic moment is derived from its timing parameters, whereas a strong field has been proposed to reside in the stellar interior and in multipole components on the surface. Here we show that the X-ray spectrum of SGR 0418+5729 has an absorption line, the properties of which depend strongly on the star's rotational phase. This line is interpreted as a proton cyclotron feature and its energy implies a magnetic field ranging from 2 × 10(14) gauss to more than 10(15) gauss.

Published
2013
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5. Discovery of powerful gamma-ray flares from the Crab Nebula.

Author

Tavani M, Bulgarelli A, Vittorini V, Pellizzoni A, Striani E, Caraveo P, Weisskopf MC, Tennant A, Pucella G, Trois A, Costa E, Evangelista Y, Pittori C, Verrecchia F, Del Monte E, Campana R, Pilia M, De Luca A, Donnarumma I, Horns D, Ferrigno C, Heinke CO, Trifoglio M, Gianotti F, Vercellone S, Argan A, Barbiellini G, Cattaneo PW, Chen AW, Contessi T, D'Ammando F, DePris G, Di Cocco G, Di Persio G, Feroci M, Ferrari A, Galli M, Giuliani A, Giusti M, Labanti C, Lapshov I, Lazzarotto F, Lipari P, Longo F, Fuschino F, Marisaldi M, Mereghetti S, Morelli E, Moretti E, Morselli A, Pacciani L, Perotti F, Piano G, Picozza P, Prest M, Rapisarda M, Rappoldi A, Rubini A, Sabatini S, Soffitta P, Vallazza E, Zambra A, Zanello D, Lucarelli F, Santolamazza P, Giommi P, Salotti L, and Bignami GF

Abstract

The well-known Crab Nebula is at the center of the SN1054 supernova remnant. It consists of a rotationally powered pulsar interacting with a surrounding nebula through a relativistic particle wind. The emissions originating from the pulsar and nebula have been considered to be essentially stable. Here, we report the detection of strong gamma-ray (100 mega-electron volts to 10 giga-electron volts) flares observed by the AGILE satellite in September 2010 and October 2007. In both cases, the total gamma-ray flux increased by a factor of three compared with the non-flaring flux. The flare luminosity and short time scale favor an origin near the pulsar, and we discuss Chandra Observatory x-ray and Hubble Space Telescope optical follow-up observations of the nebula. Our observations challenge standard models of nebular emission and require power-law acceleration by shock-driven plasma wave turbulence within an approximately 1-day time scale.

Published
2011
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6. Detection of gamma-ray emission from the Vela pulsar wind nebula with AGILE.

Author

Pellizzoni A, Trois A, Tavani M, Pilia M, Giuliani A, Pucella G, Esposito P, Sabatini S, Piano G, Argan A, Barbiellini G, Bulgarelli A, Burgay M, Caraveo P, Cattaneo PW, Chen AW, Cocco V, Contessi T, Costa E, D'Ammando F, Del Monte E, De Paris G, Di Cocco G, Di Persio G, Donnarumma I, Evangelista Y, Feroci M, Ferrari A, Fiorini M, Fuschino F, Galli M, Gianotti F, Hotan A, Labanti C, Lapshov I, Lazzarotto F, Lipari P, Longo F, Marisaldi M, Mastropietro M, Mereghetti S, Moretti E, Morselli A, Pacciani L, Palfreyman J, Perotti F, Picozza P, Pittori C, Possenti A, Prest M, Rapisarda M, Rappoldi A, Rossi E, Rubini A, Santolamazza P, Scalise E, Soffitta P, Striani E, Trifoglio M, Vallazza E, Vercellone S, Verrecchia F, Vittorini V, Zambra A, Zanello D, Giommi P, Colafrancesco S, Antonelli A, Salotti L, D'Amico N, and Bignami GF

Abstract

Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae are observed by their radio, optical, and x-ray emissions, and in some cases also at TeV (teraelectron volt) energies, but the lack of information in the gamma-ray band precludes drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified galactic gamma-ray sources.

Published
2010
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8. Detection of 16 gamma-ray pulsars through blind frequency searches using the Fermi LAT.

Author

Abdo AA, Ackermann M, Ajello M, Anderson B, Atwood WB, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring MG, Bastieri D, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Bignami GF, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cecchi C, Celik O, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, Dermer CD, de Angelis A, de Luca A, de Palma F, Digel SW, Dormody M, do Couto e Silva E, Drell PS, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan SJ, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Gwon C, Hanabata Y, Harding AK, Hayashida M, Hays E, Hughes RE, Jóhannesson G, Johnson RP, Johnson TJ, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kocian ML, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Makeev A, Marelli M, Mazziotta MN, McConville W, McEnery JE, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nolan PL, Norris JP, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes JF, Paneque D, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Pierbattista M, Piron F, Porter TA, Primack JR, Rainò S, Rando R, Ray PS, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester LS, Rodriguez AY, Romani RW, Ryde F, Sadrozinski HF, Sanchez D, Sander A, Saz Parkinson PM, Scargle JD, Sgrò C, Siskind EJ, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Strickman MS, Suson DJ, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer JG, Thompson DJ, Tibaldo L, Tibolla O, Torres DF, Tosti G, Tramacere A, Uchiyama Y, Usher TL, Van Etten A, Vasileiou V, Vilchez N, Vitale V, Waite AP, Wang P, Watters K, Winer BL, Wolff MT, Wood KS, Ylinen T, and Ziegler M

Abstract

Pulsars are rapidly rotating, highly magnetized neutron stars emitting radiation across the electromagnetic spectrum. Although there are more than 1800 known radio pulsars, until recently only seven were observed to pulse in gamma rays, and these were all discovered at other wavelengths. The Fermi Large Area Telescope (LAT) makes it possible to pinpoint neutron stars through their gamma-ray pulsations. We report the detection of 16 gamma-ray pulsars in blind frequency searches using the LAT. Most of these pulsars are coincident with previously unidentified gamma-ray sources, and many are associated with supernova remnants. Direct detection of gamma-ray pulsars enables studies of emission mechanisms, population statistics, and the energetics of pulsar wind nebulae and supernova remnants.

Published
2009
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9. A population of gamma-ray millisecond pulsars seen with the Fermi Large Area Telescope.

Author

Abdo AA, Ackermann M, Ajello M, Atwood WB, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring MG, Bastieri D, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Bignami GF, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Caliandro GA, Cameron RA, Camilo F, Caraveo PA, Carlson P, Casandjian J, Cecchi C, Celik O, Charles E, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Cominsky LR, Conrad J, Corbet R, Cutini S, Dermer CD, Desvignes G, de Angelis A, de Luca A, de Palma F, Digel SW, Dormody M, do Couto e Silva E, Drell PS, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Fegan SJ, Focke WB, Frailis M, Freire PC, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Hanabata Y, Harding AK, Hayashida M, Hays E, Hobbs G, Hughes RE, Jóhannesson G, Johnson AS, Johnson RP, Johnson TJ, Johnson WN, Johnston S, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kocian ML, Kramer M, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Makeev A, Manchester RN, Marelli M, Mazziotta MN, McConville W, McEnery JE, McLaughlin MA, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nolan PL, Norris JP, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes JF, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter TA, Rainò S, Rando R, Ransom SM, Ray PS, Razzano M, Rea N, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester LS, Rodriguez AY, Romani RW, Roth M, Ryde F, Sadrozinski HF, Sanchez D, Sander A, Saz Parkinson PM, Scargle JD, Schalk TL, Sgrò C, Siskind EJ, Smith DA, Smith PD, Spandre G, Spinelli P, Stappers BW, Starck JL, Striani E, Strickman MS, Suson DJ, Tajima H, Takahashi H, Tanaka T, Thayer JB, Thayer JG, Theureau G, Thompson DJ, Thorsett SE, Tibaldo L, Torres DF, Tosti G, Tramacere A, Uchiyama Y, Usher TL, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite AP, Wallace E, Wang P, Watters K, Webb N, Weltevrede P, Winer BL, Wood KS, Ylinen T, and Ziegler M

Abstract

Pulsars are born with subsecond spin periods and slow by electromagnetic braking for several tens of millions of years, when detectable radiation ceases. A second life can occur for neutron stars in binary systems. They can acquire mass and angular momentum from their companions, to be spun up to millisecond periods and begin radiating again. We searched Fermi Large Area Telescope data for pulsations from all known millisecond pulsars (MSPs) outside of globular clusters, using rotation parameters from radio telescopes. Strong gamma-ray pulsations were detected for eight MSPs. The gamma-ray pulse profiles and spectral properties resemble those of young gamma-ray pulsars. The basic emission mechanism seems to be the same for MSPs and young pulsars, with the emission originating in regions far from the neutron star surface.

Published
2009
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14. A long-period, violently variable X-ray source in a young supernova remnant.

Author

De Luca A, Caraveo PA, Mereghetti S, Tiengo A, and Bignami GF

Abstract

Observations with the Newton X-ray Multimirror Mission satellite show a strong periodic modulation at 6.67 +/- 0.03 hours of the x-ray source at the center of the 2000-year-old supernova remnant RCW 103. No fast pulsations are visible. If genetically tied to the supernova remnant, the source could either be an x-ray binary, composed of a compact object and a low-mass star in an eccentric orbit, or an isolated neutron star. In the latter case, the combination of its age and period would indicate that it is a peculiar magnetar, dramatically slowed down, possibly by a supernova debris disc. Both scenarios require nonstandard assumptions about the formation and evolution of compact objects in supernova explosions.

Published
2006
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15. Phase-resolved spectroscopy of Geminga shows rotating hot spot(s).

Author

Caraveo PA, De Luca A, Mereghetti S, Pellizzoni A, and Bignami GF

Abstract

Isolated neutron stars are seen in x-rays through their nonthermal and/or surface thermal emissions. X-ray Multimirror Mission-Newton observations of the Geminga pulsar show a 43-electron volt spectrum from the whole neutron star surface, as well as a power-law component above 2 kiloelectron volts. In addition, we have detected a hot (170 electron volts) thermal emission from an approximately 60-meter-radius spot on the pulsar's surface. Such a thermal emission, only visible at selected phase intervals, may be coming from polar hot spot(s), long thought to exist as a result of heating from magnetospheric accelerated particles. It may provide the missing link between the x-ray and gamma-ray emission of the pulsar.

Published
2004
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16. Geminga's tails: a pulsar bow shock probing the interstellar medium.

Author

Caraveo PA, Bignami GF, DeLuca A, Mereghetti S, Pellizzoni A, Mignani R, Tur A, and Becker W

Abstract

We report the X-ray Multimirror Mission-Newton European Photon Imaging Camera observation of two elongated parallel x-ray tails trailing the pulsar Geminga. They are aligned with the object's supersonic motion, extend for approximately 2', and have a nonthermal spectrum produced by electron-synchrotron emission in the bow shock between the pulsar wind and the surrounding medium. Electron lifetime against synchrotron cooling matches the source transit time over the x-ray features' length. Such an x-ray detection of a pulsar bow shock (with no Halpha emission) allows us to gauge the pulsar electron injection energy and the shock magnetic field while constraining the angle of Geminga's motion and the local matter density.

Published
2003
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17. The magnetic field of an isolated neutron star from X-ray cyclotron absorption lines.

Author

Bignami GF, Caraveo PA, De Luca A, and Mereghetti S

Abstract

Isolated neutron stars are highly magnetized, fast-rotating objects that form as an end point of stellar evolution. They are directly observable in X-ray emission, because of their high surface temperatures. Features in their X-ray spectra could in principle reveal the presence of atmospheres, or be used to estimate the strength of their magnetic fields through the cyclotron process, as is done for X-ray binaries. Almost all isolated neutron star spectra observed so far appear as featureless thermal continua. The only exception is 1E1207.4-5209 (refs 7-9), where two deep absorption features have been detected, but with insufficient definition to permit unambiguous interpretation. Here we report a long X-ray observation of the same object in which the star's spectrum shows three distinct features, regularly spaced at 0.7, 1.4 and 2.1 keV, plus a fourth feature of lower significance, at 2.8 keV. These features vary in phase with the star's rotation. The logical interpretation is that they are features from resonant cyclotron absorption, which allows us to calculate a magnetic field strength of 8 x 10(10) G, assuming the absorption arises from electrons.

Published
2003
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