FERMI-LAT OBSERVATIONS OF THE GEMINGA PULSAR

Abdo AA, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastier 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, Brueli P, Burnett TH, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cecchi C, Celik O, Charles E, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Dermer CD, De Palma F, Dormody M, Do Couto E Silva E, Drell PS, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Fegan SJ, Focke WB, Fortin P, Frailis M, Furazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giavitto G, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Hadasch D, Hardino AK, Hays E, Hughes RE, Johannesson G, Johnson AS, Johnson TJ, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knoedlseder J, Kuss MW, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Makeev A, Marelli M, Mazziotta MN, Mcenery JE, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenk IV, Murgia S, Nolan PL, Norris JP, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes JF, Ozaki M, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter TA, Raino S, Rando R, Rayi PS, Razzano M, Reimer A, Reimer O, Reposeur T, Rochester LS, Rodriguez AY, Romani RW, Roth M, Ryde F, Sadrozinski HFW, Sander A, Parkinson PMS, Scargle JD, Sgro C, Siskind EJ, Smith DA, Smith PD, Spandre G, Spinelli P, Strickman MS, Suson DJ, Takahashi HH, Takahashi T, Tanaka T, Thayer JB, Thayer JG, Thompson DJ, Tibaldo L, Torres DF, Tosti G, Tramacere A, Usher TL, Van Etten A, Vasileiou V, Venter C, Vilchez N, Vitale V, Waite AP, Wang P, Watters K, Winer BL, Wood KS, Ylinen T, Ziegler M (2010)

Publication Type: Journal article

Publication year: 2010

Journal

Book Volume: 720

Pages Range: 272-283

Journal Issue: 1

DOI: 10.1088/0004-637X/720/1/272

Abstract

We report on the Fermi-LAT observations of the Geminga pulsar, the second brightest non-variable GeV source in the gamma-ray sky and the first example of a radio-quiet gamma-ray pulsar. The observations cover one year, from the launch of the Fermi satellite through 2009 June 15. A data sample of over 60,000 photons enabled us to build a timing solution based solely on gamma-rays. Timing analysis shows two prominent peaks, separated by Delta phi = 0.497 +/- 0.004 in phase, which narrow with increasing energy. Pulsed gamma-rays are observed beyond 18 GeV, precluding emission below 2.7 stellar radii because of magnetic absorption. The phase-averaged spectrum was fitted with a power law with exponential cutoff of spectral index Gamma = (1.30 +/- 0.01 +/- 0.04), cutoff energy E-0 = (2.46 +/- 0.04 +/- 0.17) GeV, and an integral photon flux above 0.1 GeV of (4.14 +/- 0.02 +/- 0.32) x 10(-6) cm(-2) s(-1). The first uncertainties are statistical and the second ones are systematic. The phase-resolved spectroscopy shows a clear evolution of the spectral parameters, with the spectral index reaching a minimum value just before the leading peak and the cutoff energy having maxima around the peaks. The phase-resolved spectroscopy reveals that pulsar emission is present at all rotational phases. The spectral shape, broad pulse profile, and maximum photon energy favor the outer magnetospheric emission scenarios.

Authors with CRIS profile

Involved external institutions

U.S. Naval Research Laboratory United States (USA) (US) Stanford University United States (USA) (US) National Institute for Nuclear Physics / Istituto Nazionale di Fisica Nucleare (INFN) Italy (IT) University of Paris 7 - Denis Diderot / Université Paris VII Denis Diderot France (FR) Ohio State University United States (USA) (US) Istituto Universitario Di Studi Superiori Di Pavia Italy (IT) Politecnico di Bari Italy (IT) École Polytechnique - Université Paris-Saclay France (FR) University of Washington United States (USA) (US) Institut d'Estudis Espacials de Catalunya (IEEC) Spain (ES) National Institute for Astrophysics / Istituto Nazionale Astrofisica (INAF) Italy (IT) National Aeronautics and Space Administration (NASA) United States (USA) (US) Università degli Studi di Perugia Italy (IT) University of Montpellier / Université Montpellier France (FR) Stockholm University / Stockholms universitet Sweden (SE) University of California Santa Cruz United States (USA) (US) Université Bordeaux 1, Sciences et Technologies France (FR) University of Udine / Università degli Studi di Udine Italy (IT) ASI Science Data Center (ASDC) Italy (IT) Hiroshima University Japan (JP) Waseda University / 早稲田大学 Japan (JP) Tokyo Institute of Technology Japan (JP) National Center for Scientific Research / Centre national de la recherche scientifique (CNRS) France (FR) AlbaNova University Centre / Kungliga Tekniska Högskolan AlbaNova Universitetscentrum Sweden (SE) NYCB Real-Time Computing, Inc. United States (USA) (US) University of Alabama in Huntsville (UAH) United States (USA) (US) Institució Catalana de Recerca i Estudis Avançats (ICREA) / Catalan Institution for Research and Advanced Studies Spain (ES) University of Denver United States (USA) (US) Max-Planck-Institut für extraterrestrische Physik (MPE) / Max Planck Institute for Extraterrestrial Physics Germany (DE) Japan Aerospace eXploration Agency (JAXA) Japan (JP) Purdue University Northwest / Purdue University Calumet United States (USA) (US) Consorzio Interuniversitario per la Fisica Spaziale (CIFS) Italy (IT) Noordwes-Universiteit / North-West University South Africa (ZA)

How to cite

APA:

Abdo, A.A., Ackermann, M., Ajello, M., Baldini, L., Ballet, J., Barbiellini, G.,... Ziegler, M. (2010). FERMI-LAT OBSERVATIONS OF THE GEMINGA PULSAR. Astrophysical Journal, 720(1), 272-283. https://doi.org/10.1088/0004-637X/720/1/272

MLA:

Abdo, A. A., et al. "FERMI-LAT OBSERVATIONS OF THE GEMINGA PULSAR." Astrophysical Journal 720.1 (2010): 272-283.

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