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Your search keyword '"BELLAZZINI, R."' showing total 15 results
Start Over Author "BELLAZZINI, R." Journal physical review letters
15 results on '"BELLAZZINI, R."'

1. Inferred Cosmic-Ray Spectrum from Fermi Large Area Telescope γ-Ray Observations of Earth’s Limb

Author

Ackermann, M, Ajello, M, Albert, A, Allafort, A, Baldini, L, Barbiellini, G, Bastieri, D, Bechtol, K, Bellazzini, R, Blandford, RD, Bloom, ED, Bonamente, E, Bottacini, E, Bouvier, A, Brandt, TJ, Brigida, M, Bruel, P, Buehler, R, Buson, S, Caliandro, GA, Cameron, RA, Caraveo, PA, Cecchi, C, Charles, E, Chaves, RCG, Chekhtman, A, Chiang, J, Chiaro, G, Ciprini, S, Claus, R, Cohen-Tanugi, J, Conrad, J, Cutini, S, Dalton, M, D'Ammando, F, de Angelis, A, de Palma, F, Dermer, CD, Digel, SW, Di Venere, L, do Couto e Silva, E, Drell, PS, Drlica-Wagner, A, Favuzzi, C, Fegan, SJ, Ferrara, EC, Focke, WB, Franckowiak, A, Fukazawa, Y, Funk, S, Fusco, P, Gargano, F, Gasparrini, D, Germani, S, Giglietto, N, Giordano, F, Giroletti, M, Glanzman, T, Godfrey, G, Gomez-Vargas, GA, Grenier, IA, Grove, JE, Guiriec, S, Gustafsson, M, Hadasch, D, Hanabata, Y, Harding, AK, Hayashida, M, Hayashi, K, Hewitt, JW, Horan, D, Hou, X, Hughes, RE, Inoue, Y, Jackson, MS, Jogler, T, Jóhannesson, G, Johnson, AS, Kamae, T, Kawano, T, Knödlseder, J, Kuss, M, Lande, J, Larsson, S, Latronico, L, Longo, F, Loparco, F, Lovellette, MN, Lubrano, P, Mayer, M, Mazziotta, MN, McEnery, JE, Mehault, J, Michelson, PF, Mitthumsiri, W, Mizuno, T, Moiseev, AA, Monte, C, Monzani, ME, and Morselli, A

Subjects
Fermi LAT Collaboration, astro-ph.HE, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract

Recent accurate measurements of cosmic-ray (CR) species by ATIC-2, CREAM, and PAMELA reveal an unexpected hardening in the proton and He spectra above a few hundred GeV, a gradual softening of the spectra just below a few hundred GeV, and a harder spectrum of He compared to that of protons. These newly discovered features may offer a clue to the origin of high-energy CRs. We use the Fermi Large Area Telescope observations of the γ-ray emission from Earth's limb for an indirect measurement of the local spectrum of CR protons in the energy range ∼90  GeV-6  TeV (derived from a photon energy range 15 GeV-1 TeV). Our analysis shows that single power law and broken power law spectra fit the data equally well and yield a proton spectrum with index 2.68±0.04 and 2.61±0.08 above ∼200  GeV, respectively.

Published
2014

2. Search for Spectral Irregularities due to Photon-Axionlike-Particle Oscillations with the Fermi Large Area Telescope

Author

Ajello, M, Albert, A, Anderson, B, Baldini, L, Barbiellini, G, Bastieri, D, Bellazzini, R, Bissaldi, E, Blandford, R.D, Mirabal, N, Guiriec, S, Perkins, J. S, and Troja, E

Subjects
Astrophysics
Abstract

We report on the search for spectral irregularities induced by oscillations between photons and axion-like particles (ALPs) in the gamma-ray spectrum of NGC 1275, the central galaxy of the Perseus cluster. Using 6 years of Fermi Large Area Telescope data, we find no evidence for ALPs and exclude couplings above 5 times 10 (sup -12) per gigaelectronvolt for ALP masses less than or approximately equal to 0.5 apparent magnitude (m (sub a)) less than or approximately equal to 5 nanoelectronvolts at 95 percent confidence. The limits are competitive withthe sensitivity of planned laboratory experiments, and, together with other bounds, strongly constrain thepossibility that ALPs can reduce the gamma-ray opacity of the Universe.

Published
2016
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3. Unresolved Gamma-Ray Sky through its Angular Power Spectrum

Author

Ackermann, M., Ajello, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Bissaldi, E., Blandford, R. D., Bonino, R., Bottacini, E., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Negro, M., Nuss, E., ORIENTI, Monica, Orlando, E., Palatiello, M., Paliya, V. S., PERSIC, Massimo, Paneque, D., Pesce-Rollins, M., Petrosian, V., Piron, F., Porter, T. A., Principe, G., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, O., Reimer, A., Serini, D., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Suson, D. J., Tajima, H., Takahashi, M., Thayer, J. B., Torres, D. F., Tibaldo, L., Troja, E., Venters, T. M., Vianello, G., Wood, K., Yassine, M., Zaharijas, G., Ammazzalorso, S., Fornengo, N., Regis, M., Bregeon, J., Fermi-LAT Collaboration, Bruel, P., Buehler, R., Burns, E., Buson, S., Cameron, R. A., Caputo, R., CARAVEO, PATRIZIA, Cavazzuti, E., Chen, S., Chiaro, G., Ciprini, S., Costantin, D., Cuoco, A., Cutini, S., D'AMMANDO, FILIPPO, de la Torre Luque, P., de Palma, F., Desai, A., Digel, S. W., Di Lalla, N., Di Mauro, M., Di Venere, L., Fana Dirirsa, F., Favuzzi, C., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giordano, F., GIROLETTI, MARCELLO, Green, D., Grenier, I. A., Guillemot, L., Guiriec, S., Horan, D., Jóhannesson, G., Kuss, M., Larsson, S., Latronico, L., Li, J., Liodakis, I., Longo, F., Loparco, F., Lubrano, P., Magill, J. D., Maldera, S., Malyshev, D., Manfreda, A., Mazziotta, M. N., Mereu, I., Michelson, P. F., Mitthumsiri, W., 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), Laboratoire Univers et Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-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), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), 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), Fermi-LAT, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), 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), 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), 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)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), 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), ITA, Ackermann, M., Ajello, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Bissaldi, E., Blandford, R. D., Bonino, R., Bottacini, E., Bregeon, J., Bruel, P., Buehler, R., Burns, E., Buson, S., Cameron, R. A., Caputo, R., Caraveo, P. A., Cavazzuti, E., Chen, S., Chiaro, G., Ciprini, S., Costantin, D., Cuoco, A., Cutini, S., D'Ammando, F., de la Torre Luque, P., de Palma, F., Desai, A., Digel, S. W., Di Lalla, N., Di Mauro, M., Di Venere, L., Fana Dirirsa, F., Favuzzi, C., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giordano, F., Giroletti, M., Green, D., Grenier, I. A., Guillemot, L., Guiriec, S., Horan, D., Jóhannesson, G., Kuss, M., Larsson, S., Latronico, L., Li, J., Liodakis, I., Longo, F., Loparco, F., Lubrano, P., Magill, J. D., Maldera, S., Malyshev, D., Manfreda, A., Mazziotta, M. N., Mereu, I., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Negro, M., Nuss, E., Orienti, M., Orlando, E., Palatiello, M., Paliya, V. S., Paneque, D., Persic, M., Pesce-Rollins, M., Petrosian, V., Piron, F., Porter, T. A., Principe, G., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Serini, D., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Suson, D. J., Tajima, H., Takahashi, M., Thayer, J. B., Tibaldo, L., Torres, D. F., Troja, E., Venters, T. M., Vianello, G., Wood, K., Yassine, M., Zaharijas, G., Ammazzalorso, S., Fornengo, N., Regis, M., and 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)

Subjects
noise, Photon, Cosmology and Nongalactic Astrophysics (astro-ph.CO), gamma ray: background, High-energy astronomy, High-energy Astrophysics, media_common.quotation_subject, Astrophysics::High Energy Astrophysical Phenomena, General Physics and Astronomy, FOS: Physical sciences, Astrophysics, Gravitation and Astrophysics, 01 natural sciences, GLAST, law.invention, Telescope, Physics and Astronomy (all), High Energy Physics - Phenomenology (hep-ph), law, 0103 physical sciences, ddc:530, 010303 astronomy & astrophysics, media_common, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), energy: high, 010308 nuclear & particles physics, fluctuation, photon, Physics and Astronomy, Spectral density, sensitivity, High Energy Physics - Phenomenology, Amplitude, Sky, [SDU]Sciences of the Universe [physics], power spectrum: angular dependence, energy spectrum: anisotropy, Astrophysics - High Energy Astrophysical Phenomena, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Noise (radio), Fermi Gamma-ray Space Telescope, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

The gamma-ray sky has been observed with unprecedented accuracy in the last decade by the Fermi large area telescope (LAT), allowing us to resolve and understand the high-energy Universe. The nature of the remaining unresolved emission (unresolved gamma-ray background, UGRB) below the LAT source detection threshold can be uncovered by characterizing the amplitude and angular scale of the UGRB fluctuation field. This work presents a measurement of the UGRB autocorrelation angular power spectrum based on eight years of Fermi LAT Pass 8 data products. The analysis is designed to be robust against contamination from resolved sources and noise systematics. The sensitivity to subthreshold sources is greatly enhanced with respect to previous measurements. We find evidence (with $\sim$3.7$\sigma$ significance) that the scenario in which two classes of sources contribute to the UGRB signal is favored over a single class. A double power law with exponential cutoff can explain the anisotropy energy spectrum well, with photon indices of the two populations being 2.55 $\pm$ 0.23 and 1.86 $\pm$ 0.15., Comment: 8 + 12 (SOM) pages, Contact author: Michela Negro (michela.negro@to.infn.it). (Typos in Tab. VII in previous versions)

Published
2018
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4. Resolving the Extragalacticγ-Ray Background above 50 GeV with the Fermi Large Area Telescope

Author

Ackermann, M., primary, Ajello, M., additional, Albert, A., additional, Atwood, W. B., additional, Baldini, L., additional, Ballet, J., additional, Barbiellini, G., additional, Bastieri, D., additional, Bechtol, K., additional, Bellazzini, R., additional, Bissaldi, E., additional, Blandford, R. D., additional, Bloom, E. D., additional, Bonino, R., additional, Bregeon, J., additional, Britto, R. J., additional, Bruel, P., additional, Buehler, R., additional, Caliandro, G. A., additional, Cameron, R. A., additional, Caragiulo, M., additional, Caraveo, P. A., additional, Cavazzuti, E., additional, Cecchi, C., additional, Charles, E., additional, Chekhtman, A., additional, Chiang, J., additional, Chiaro, G., additional, Ciprini, S., additional, Cohen-Tanugi, J., additional, Cominsky, L. R., additional, Costanza, F., additional, Cutini, S., additional, D’Ammando, F., additional, de Angelis, A., additional, de Palma, F., additional, Desiante, R., additional, Digel, S. W., additional, Di Mauro, M., additional, Di Venere, L., additional, Domínguez, A., additional, Drell, P. S., additional, Favuzzi, C., additional, Fegan, S. J., additional, Ferrara, E. C., additional, Franckowiak, A., additional, Fukazawa, Y., additional, Funk, S., additional, Fusco, P., additional, Gargano, F., additional, Gasparrini, D., additional, Giglietto, N., additional, Giommi, P., additional, Giordano, F., additional, Giroletti, M., additional, Godfrey, G., additional, Green, D., additional, Grenier, I. A., additional, Guiriec, S., additional, Hays, E., additional, Horan, D., additional, Iafrate, G., additional, Jogler, T., additional, Jóhannesson, G., additional, Kuss, M., additional, La Mura, G., additional, Larsson, S., additional, Latronico, L., additional, Li, J., additional, Li, L., additional, Longo, F., additional, Loparco, F., additional, Lott, B., additional, Lovellette, M. N., additional, Lubrano, P., additional, Madejski, G. M., additional, Magill, J., additional, Maldera, S., additional, Manfreda, A., additional, Mayer, M., additional, Mazziotta, M. N., additional, Michelson, P. F., additional, Mitthumsiri, W., additional, Mizuno, T., additional, Moiseev, A. A., additional, Monzani, M. E., additional, Morselli, A., additional, Moskalenko, I. V., additional, Murgia, S., additional, Negro, M., additional, Nuss, E., additional, Ohsugi, T., additional, Okada, C., additional, Omodei, N., additional, Orlando, E., additional, Ormes, J. F., additional, Paneque, D., additional, Perkins, J. S., additional, Pesce-Rollins, M., additional, Petrosian, V., additional, Piron, F., additional, Pivato, G., additional, Porter, T. A., additional, Rainò, S., additional, Rando, R., additional, Razzano, M., additional, Razzaque, S., additional, Reimer, A., additional, Reimer, O., additional, Reposeur, T., additional, Romani, R. W., additional, Sánchez-Conde, M., additional, Schmid, J., additional, Schulz, A., additional, Sgrò, C., additional, Simone, D., additional, Siskind, E. J., additional, Spada, F., additional, Spandre, G., additional, Spinelli, P., additional, Suson, D. J., additional, Takahashi, H., additional, Thayer, J. B., additional, Tibaldo, L., additional, Torres, D. F., additional, Troja, E., additional, Vianello, G., additional, Yassine, M., additional, and Zimmer, S., additional

Published
2016
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5. Measurement of the Cosmic Ray e++e- Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope

Author

A., A. Abdo, Ackermann, M., Ajello, M., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Battelino, M., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bogaert, G., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Carlson, P., Casandjian, J. M., Cecchi, C., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cominsky, L. R., Conrad, J., Cutini, S., Dermer, C. D., de, Angelis A., de, Palma F., Digel, S. W., Di, Bernardo G., do, Couto e Silva E., Drell, P. S., Dubois, R., Dumora, D., Edmonds, Y., Farnier, C., Favuzzi, C., Focke, W. B., Frailis, M., Fukazawa, Y., Funk, S., Fusco, P., Gaggero, D., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grasso, D., Grenier, I. A., Grondin, M.-H., Grove, J. E., Guillemot, L., Guiriec, S., Hanabata, Y., Harding, A. K., Hartman, R. C., Hayashida, M., Hays, E., Hughes, R. E., Johannesson, G., Johnson, A. S., Johnson, R. P., Johnson, W. N., Kamae, T., Katarigi, H., Kataoka, J., Kawai, N., Kerr, M., Knodlseder, J., Kocevski, D., Kuehn, F., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Massai, M. M., Mazziotta, M. N., McConville, W., McEnery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Moretti, E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, Masanobu, Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Pohl, M., Porter, T. A., Profumo, S., Raino, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Romani, R. W., Roth, M., Ryde, F., Sadrozinski, H. F.-W., Sanchez, D., Sander, A., Saz, Parkinson P. M., Scargle, J. D., Schalk, T. L., Sellerholm, A., Sgro, C., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Starck, J.-L., Stephens, T. E., Strickman, M. S., Strong, A. W., Suson, D. J., Tajima, H., Takahashi, H., and Takahashi, Tadayuki

Abstract

著者人数：189名, 資料番号: SA1001002000

Published
2009

6. Spectrum of the Isotropic Diffuse Gamma-Ray Emission Derived from First-Year Fermi Large Area Telescope Data

Author

Abdo, A. A., primary, Ackermann, M., additional, Ajello, M., additional, Atwood, W. B., additional, Baldini, L., additional, Ballet, J., additional, Barbiellini, G., additional, Bastieri, D., additional, Baughman, B. M., additional, Bechtol, K., additional, Bellazzini, R., additional, Berenji, B., additional, Blandford, R. D., additional, Bloom, E. D., additional, Bonamente, E., additional, Borgland, A. W., additional, Bregeon, J., additional, Brez, A., additional, Brigida, M., additional, Bruel, P., additional, Burnett, T. H., additional, Buson, S., additional, Caliandro, G. A., additional, Cameron, R. A., additional, Caraveo, P. A., additional, Casandjian, J. M., additional, Cavazzuti, E., additional, Cecchi, C., additional, Çelik, Ö., additional, Charles, E., additional, Chekhtman, A., additional, Cheung, C. C., additional, Chiang, J., additional, Ciprini, S., additional, Claus, R., additional, Cohen-Tanugi, J., additional, Cominsky, L. R., additional, Conrad, J., additional, Cutini, S., additional, Dermer, C. D., additional, de Angelis, A., additional, de Palma, F., additional, Digel, S. W., additional, Di Bernardo, G., additional, e Silva, E. do Couto, additional, Drell, P. S., additional, Drlica-Wagner, A., additional, Dubois, R., additional, Dumora, D., additional, Farnier, C., additional, Favuzzi, C., additional, Fegan, S. J., additional, Focke, W. B., additional, Fortin, P., additional, Frailis, M., additional, Fukazawa, Y., additional, Funk, S., additional, Fusco, P., additional, Gaggero, D., additional, Gargano, F., additional, Gasparrini, D., additional, Gehrels, N., additional, Germani, S., additional, Giebels, B., additional, Giglietto, N., additional, Giommi, P., additional, Giordano, F., additional, Glanzman, T., additional, Godfrey, G., additional, Grenier, I. A., additional, Grondin, M.-H., additional, Grove, J. E., additional, Guillemot, L., additional, Guiriec, S., additional, Gustafsson, M., additional, Hanabata, Y., additional, Harding, A. K., additional, Hayashida, M., additional, Hughes, R. E., additional, Itoh, R., additional, Jackson, M. S., additional, Jóhannesson, G., additional, Johnson, A. S., additional, Johnson, R. P., additional, Johnson, T. J., additional, Johnson, W. N., additional, Kamae, T., additional, Katagiri, H., additional, Kataoka, J., additional, Kawai, N., additional, Kerr, M., additional, Knödlseder, J., additional, Kocian, M. L., additional, Kuehn, F., additional, Kuss, M., additional, Lande, J., additional, Latronico, L., additional, Lemoine-Goumard, M., additional, Longo, F., additional, Loparco, F., additional, Lott, B., additional, Lovellette, M. N., additional, Lubrano, P., additional, Madejski, G. M., additional, Makeev, A., additional, Mazziotta, M. N., additional, McConville, W., additional, McEnery, J. E., additional, Meurer, C., additional, Michelson, P. F., additional, Mitthumsiri, W., additional, Mizuno, T., additional, Moiseev, A. A., additional, Monte, C., additional, Monzani, M. E., additional, Morselli, A., additional, Moskalenko, I. V., additional, Murgia, S., additional, Nolan, P. L., additional, Norris, J. P., additional, Nuss, E., additional, Ohsugi, T., additional, Omodei, N., additional, Orlando, E., additional, Ormes, J. F., additional, Paneque, D., additional, Panetta, J. H., additional, Parent, D., additional, Pelassa, V., additional, Pepe, M., additional, Pesce-Rollins, M., additional, Piron, F., additional, Porter, T. A., additional, Rainò, S., additional, Rando, R., additional, Razzano, M., additional, Reimer, A., additional, Reimer, O., additional, Reposeur, T., additional, Ritz, S., additional, Rochester, L. S., additional, Rodriguez, A. Y., additional, Roth, M., additional, Ryde, F., additional, Sadrozinski, H. F.-W., additional, Sanchez, D., additional, Sander, A., additional, Parkinson, P. M. Saz, additional, Scargle, J. D., additional, Sellerholm, A., additional, Sgrò, C., additional, Shaw, M. S., additional, Siskind, E. J., additional, Smith, D. A., additional, Smith, P. D., additional, Spandre, G., additional, Spinelli, P., additional, Starck, J.-L., additional, Strickman, M. S., additional, Strong, A. W., additional, Suson, D. J., additional, Tajima, H., additional, Takahashi, H., additional, Takahashi, T., additional, Tanaka, T., additional, Thayer, J. B., additional, Thayer, J. G., additional, Thompson, D. J., additional, Tibaldo, L., additional, Torres, D. F., additional, Tosti, G., additional, Tramacere, A., additional, Uchiyama, Y., additional, Usher, T. L., additional, Vasileiou, V., additional, Vilchez, N., additional, Vitale, V., additional, Waite, A. P., additional, Wang, P., additional, Winer, B. L., additional, Wood, K. S., additional, Ylinen, T., additional, and Ziegler, M., additional

Published
2010
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7. Fermi Large Area Telescope Search for Photon Lines from 30 to 200 GeV and Dark Matter Implications

Author

Abdo, A. A., primary, Ackermann, M., additional, Ajello, M., additional, Atwood, W. B., additional, Baldini, L., additional, Ballet, J., additional, Barbiellini, G., additional, Bastieri, D., additional, Bechtol, K., additional, Bellazzini, R., additional, Berenji, B., additional, Bloom, E. D., additional, Bonamente, E., additional, Borgland, A. W., additional, Bouvier, A., additional, Bregeon, J., additional, Brez, A., additional, Brigida, M., additional, Bruel, P., additional, Burnett, T. H., additional, Buson, S., additional, Caliandro, G. A., additional, Cameron, R. A., additional, Caraveo, P. A., additional, Carrigan, S., additional, Casandjian, J. M., additional, Cecchi, C., additional, Çelik, Ö., additional, Chekhtman, A., additional, Chiang, J., additional, Ciprini, S., additional, Claus, R., additional, Cohen-Tanugi, J., additional, Conrad, J., additional, Dermer, C. D., additional, de Angelis, A., additional, de Palma, F., additional, Digel, S. W., additional, do Couto e Silva, E., additional, Drell, P. S., additional, Drlica-Wagner, A., additional, Dubois, R., additional, Dumora, D., additional, Edmonds, Y., additional, Essig, R., additional, Farnier, C., additional, Favuzzi, C., additional, Fegan, S. J., additional, Focke, W. B., additional, Fortin, P., additional, Frailis, M., additional, Fukazawa, Y., additional, Funk, S., additional, Fusco, P., additional, Gargano, F., additional, Gasparrini, D., additional, Gehrels, N., additional, Germani, S., additional, Giglietto, N., additional, Giordano, F., additional, Glanzman, T., additional, Godfrey, G., additional, Grenier, I. A., additional, Grove, J. E., additional, Guillemot, L., additional, Guiriec, S., additional, Gustafsson, M., additional, Hadasch, D., additional, Harding, A. K., additional, Horan, D., additional, Hughes, R. E., additional, Jackson, M. S., additional, Jóhannesson, G., additional, Johnson, A. S., additional, Johnson, R. P., additional, Johnson, W. N., additional, Kamae, T., additional, Katagiri, H., additional, Kataoka, J., additional, Kawai, N., additional, Kerr, M., additional, Knödlseder, J., additional, Kuss, M., additional, Lande, J., additional, Latronico, L., additional, Llena Garde, M., additional, Longo, F., additional, Loparco, F., additional, Lott, B., additional, Lovellette, M. N., additional, Lubrano, P., additional, Makeev, A., additional, Mazziotta, M. N., additional, McEnery, J. E., additional, Meurer, C., additional, Michelson, P. F., additional, Mitthumsiri, W., additional, Mizuno, T., additional, Moiseev, A. A., additional, Monte, C., additional, Monzani, M. E., additional, Morselli, A., additional, Moskalenko, I. V., additional, Murgia, S., additional, Nolan, P. L., additional, Norris, J. P., additional, Nuss, E., additional, Ohsugi, T., additional, Omodei, N., additional, Orlando, E., additional, Ormes, J. F., additional, Ozaki, M., additional, Paneque, D., additional, Panetta, J. H., additional, Parent, D., additional, Pelassa, V., additional, Pepe, M., additional, Pesce-Rollins, M., additional, Piron, F., additional, Rainò, S., additional, Rando, R., additional, Razzano, M., additional, Reimer, A., additional, Reimer, O., additional, Reposeur, T., additional, Ripken, J., additional, Ritz, S., additional, Rodriguez, A. Y., additional, Roth, M., additional, Sadrozinski, H. F.-W., additional, Sander, A., additional, Parkinson, P. M. Saz, additional, Scargle, J. D., additional, Schalk, T. L., additional, Sellerholm, A., additional, Sgrò, C., additional, Siskind, E. J., additional, Smith, D. A., additional, Smith, P. D., additional, Spandre, G., additional, Spinelli, P., additional, Starck, J.-L., additional, Strickman, M. S., additional, Suson, D. J., additional, Tajima, H., additional, Takahashi, H., additional, Tanaka, T., additional, Thayer, J. B., additional, Thayer, J. G., additional, Tibaldo, L., additional, Torres, D. F., additional, Uchiyama, Y., additional, Usher, T. L., additional, Vasileiou, V., additional, Vilchez, N., additional, Vitale, V., additional, Waite, A. P., additional, Wang, P., additional, Winer, B. L., additional, Wood, K. S., additional, Ylinen, T., additional, and Ziegler, M., additional

Published
2010
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8. Fermi Large Area Telescope Measurements of the Diffuse Gamma-Ray Emission at Intermediate Galactic Latitudes

Author

Abdo, A. A., primary, Ackermann, M., additional, Ajello, M., additional, Anderson, B., additional, Atwood, W. B., additional, Axelsson, M., additional, Baldini, L., additional, Ballet, J., additional, Barbiellini, G., additional, Bastieri, D., additional, Baughman, B. M., additional, Bechtol, K., additional, Bellazzini, R., additional, Berenji, B., additional, Blandford, R. D., additional, Bloom, E. D., additional, Bonamente, E., additional, Borgland, A. W., additional, Bregeon, J., additional, Brez, A., additional, Brigida, M., additional, Bruel, P., additional, Burnett, T. H., additional, Caliandro, G. A., additional, Cameron, R. A., additional, Caraveo, P. A., additional, Casandjian, J. M., additional, Cecchi, C., additional, Charles, E., additional, Chekhtman, A., additional, Cheung, C. C., additional, Chiang, J., additional, Ciprini, S., additional, Claus, R., additional, Cohen-Tanugi, J., additional, Conrad, J., additional, Dereli, H., additional, Dermer, C. D., additional, de Angelis, A., additional, de Palma, F., additional, Digel, S. W., additional, Di Bernardo, G., additional, Dormody, M., additional, do Couto e Silva, E., additional, Drell, P. S., additional, Dubois, R., additional, Dumora, D., additional, Edmonds, Y., additional, Farnier, C., additional, Favuzzi, C., additional, Fegan, S. J., additional, Focke, W. B., additional, Frailis, M., additional, Fukazawa, Y., additional, Funk, S., additional, Fusco, P., additional, Gaggero, D., additional, Gargano, F., additional, Gehrels, N., additional, Germani, S., additional, Giebels, B., additional, Giglietto, N., additional, Giordano, F., additional, Glanzman, T., additional, Godfrey, G., additional, Grenier, I. A., additional, Grondin, M.-H., additional, Grove, J. E., additional, Guillemot, L., additional, Guiriec, S., additional, Hanabata, Y., additional, Harding, A. K., additional, Hayashida, M., additional, Hays, E., additional, Hughes, R. E., additional, Jóhannesson, G., additional, Johnson, A. S., additional, Johnson, R. P., additional, Johnson, T. J., additional, Johnson, W. N., additional, Kamae, T., additional, Katagiri, H., additional, Kataoka, J., additional, Kawai, N., additional, Kerr, M., additional, Knödlseder, J., additional, Kocian, M. L., additional, Kuehn, F., additional, Kuss, M., additional, Lande, J., additional, Latronico, L., additional, Longo, F., additional, Loparco, F., additional, Lott, B., additional, Lovellette, M. N., additional, Lubrano, P., additional, Madejski, G. M., additional, Makeev, A., additional, Mazziotta, M. N., additional, McConville, W., additional, McEnery, J. E., additional, Meurer, C., additional, Michelson, P. F., additional, Mitthumsiri, W., additional, Mizuno, T., additional, Moiseev, A. A., additional, Monte, C., additional, Monzani, M. E., additional, Morselli, A., additional, Moskalenko, I. V., additional, Murgia, S., additional, Nolan, P. L., additional, Nuss, E., additional, Ohsugi, T., additional, Okumura, A., additional, Omodei, N., additional, Orlando, E., additional, Ormes, J. F., additional, Paneque, D., additional, Panetta, J. H., additional, Parent, D., additional, Pelassa, V., additional, Pepe, M., additional, Pesce-Rollins, M., additional, Piron, F., additional, Porter, T. A., additional, Rainò, S., additional, Rando, R., additional, Razzano, M., additional, Reimer, A., additional, Reimer, O., additional, Reposeur, T., additional, Ritz, S., additional, Rodriguez, A. Y., additional, Roth, M., additional, Ryde, F., additional, Sadrozinski, H. F.-W., additional, Sanchez, D., additional, Sander, A., additional, Saz Parkinson, P. M., additional, Scargle, J. D., additional, Sellerholm, A., additional, Sgrò, C., additional, Smith, D. A., additional, Smith, P. D., additional, Spandre, G., additional, Spinelli, P., additional, Starck, J.-L., additional, Stecker, F. W., additional, Striani, E., additional, Strickman, M. S., additional, Strong, A. W., additional, Suson, D. J., additional, Tajima, H., additional, Takahashi, H., additional, Tanaka, T., additional, Thayer, J. B., additional, Thayer, J. G., additional, Thompson, D. J., additional, Tibaldo, L., additional, Torres, D. F., additional, Tosti, G., additional, Tramacere, A., additional, Uchiyama, Y., additional, Usher, T. L., additional, Vasileiou, V., additional, Vilchez, N., additional, Vitale, V., additional, Waite, A. P., additional, Wang, P., additional, Winer, B. L., additional, Wood, K. S., additional, Ylinen, T., additional, and Ziegler, M., additional

Published
2009
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9. Measurement of the Cosmic Raye++e−Spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope

Author

Abdo, A. A., primary, Ackermann, M., additional, Ajello, M., additional, Atwood, W. B., additional, Axelsson, M., additional, Baldini, L., additional, Ballet, J., additional, Barbiellini, G., additional, Bastieri, D., additional, Battelino, M., additional, Baughman, B. M., additional, Bechtol, K., additional, Bellazzini, R., additional, Berenji, B., additional, Blandford, R. D., additional, Bloom, E. D., additional, Bogaert, G., additional, Bonamente, E., additional, Borgland, A. W., additional, Bregeon, J., additional, Brez, A., additional, Brigida, M., additional, Bruel, P., additional, Burnett, T. H., additional, Caliandro, G. A., additional, Cameron, R. A., additional, Caraveo, P. A., additional, Carlson, P., additional, Casandjian, J. M., additional, Cecchi, C., additional, Charles, E., additional, Chekhtman, A., additional, Cheung, C. C., additional, Chiang, J., additional, Ciprini, S., additional, Claus, R., additional, Cohen-Tanugi, J., additional, Cominsky, L. R., additional, Conrad, J., additional, Cutini, S., additional, Dermer, C. D., additional, de Angelis, A., additional, de Palma, F., additional, Digel, S. W., additional, Di Bernardo, G., additional, do Couto e Silva, E., additional, Drell, P. S., additional, Dubois, R., additional, Dumora, D., additional, Edmonds, Y., additional, Farnier, C., additional, Favuzzi, C., additional, Focke, W. B., additional, Frailis, M., additional, Fukazawa, Y., additional, Funk, S., additional, Fusco, P., additional, Gaggero, D., additional, Gargano, F., additional, Gasparrini, D., additional, Gehrels, N., additional, Germani, S., additional, Giebels, B., additional, Giglietto, N., additional, Giordano, F., additional, Glanzman, T., additional, Godfrey, G., additional, Grasso, D., additional, Grenier, I. A., additional, Grondin, M.-H., additional, Grove, J. E., additional, Guillemot, L., additional, Guiriec, S., additional, Hanabata, Y., additional, Harding, A. K., additional, Hartman, R. C., additional, Hayashida, M., additional, Hays, E., additional, Hughes, R. E., additional, Jóhannesson, G., additional, Johnson, A. S., additional, Johnson, R. P., additional, Johnson, W. N., additional, Kamae, T., additional, Katagiri, H., additional, Kataoka, J., additional, Kawai, N., additional, Kerr, M., additional, Knödlseder, J., additional, Kocevski, D., additional, Kuehn, F., additional, Kuss, M., additional, Lande, J., additional, Latronico, L., additional, Lemoine-Goumard, M., additional, Longo, F., additional, Loparco, F., additional, Lott, B., additional, Lovellette, M. N., additional, Lubrano, P., additional, Madejski, G. M., additional, Makeev, A., additional, Massai, M. M., additional, Mazziotta, M. N., additional, McConville, W., additional, McEnery, J. E., additional, Meurer, C., additional, Michelson, P. F., additional, Mitthumsiri, W., additional, Mizuno, T., additional, Moiseev, A. A., additional, Monte, C., additional, Monzani, M. E., additional, Moretti, E., additional, Morselli, A., additional, Moskalenko, I. V., additional, Murgia, S., additional, Nolan, P. L., additional, Norris, J. P., additional, Nuss, E., additional, Ohsugi, T., additional, Omodei, N., additional, Orlando, E., additional, Ormes, J. F., additional, Ozaki, M., additional, Paneque, D., additional, Panetta, J. H., additional, Parent, D., additional, Pelassa, V., additional, Pepe, M., additional, Pesce-Rollins, M., additional, Piron, F., additional, Pohl, M., additional, Porter, T. A., additional, Profumo, S., additional, Rainò, S., additional, Rando, R., additional, Razzano, M., additional, Reimer, A., additional, Reimer, O., additional, Reposeur, T., additional, Ritz, S., additional, Rochester, L. S., additional, Rodriguez, A. Y., additional, Romani, R. W., additional, Roth, M., additional, Ryde, F., additional, Sadrozinski, H. F.-W., additional, Sanchez, D., additional, Sander, A., additional, Saz Parkinson, P. M., additional, Scargle, J. D., additional, Schalk, T. L., additional, Sellerholm, A., additional, Sgrò, C., additional, Smith, D. A., additional, Smith, P. D., additional, Spandre, G., additional, Spinelli, P., additional, Starck, J.-L., additional, Stephens, T. E., additional, Strickman, M. S., additional, Strong, A. W., additional, Suson, D. J., additional, Tajima, H., additional, Takahashi, H., additional, Takahashi, T., additional, Tanaka, T., additional, Thayer, J. B., additional, Thayer, J. G., additional, Thompson, D. J., additional, Tibaldo, L., additional, Tibolla, O., additional, Torres, D. F., additional, Tosti, G., additional, Tramacere, A., additional, Uchiyama, Y., additional, Usher, T. L., additional, Van Etten, A., additional, Vasileiou, V., additional, Vilchez, N., additional, Vitale, V., additional, Waite, A. P., additional, Wallace, E., additional, Wang, P., additional, Winer, B. L., additional, Wood, K. S., additional, Ylinen, T., additional, and Ziegler, M., additional

Published
2009
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10. Searching for Dark Matter Annihilation from Milky Way Dwarf Spheroidal Galaxies with Six Years of Fermi Large Area Telescope Data.

Author

Ackermann, M., Buehler, R., Mayer, M., Schulz, A., Chiaro, G., Bechtol, K., Bellazzini, R., Kuss, M., Pivato, G., Razzano, M., Sgrò, C., Spada, F., Spandre, G., Bissaldi, E., Caragiulo, M., Gargano, F., Mazziotta, M. N., de Palma, F., Favuzzi, C., and Fusco, P.

Subjects
*DARK matter, *FERMI Gamma-ray Space Telescope (Spacecraft), *WEAKLY interacting massive particles, *DWARF galaxies, *TELESCOPES, *GAMMA rays, *KINEMATICS, *ANNIHILATION reactions, *MILKY Way, *NEGATIVE tau lepton
Abstract

The article talks about nonbaryonic cold Dark Matter (DM) which forms nearly 26% of the universe who's attractive candidate is Weakly interacting massive particles (WIMPs). Large amount of WIMP allows production of y rays observable by the Fermi Large Area Telescope (LAT). According to Kinematic data dwarf spheroidal satellite galaxies (dSphs) of the Milky Way constitutes of DM component.

Published
2015
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11. Resolving the Extragalactic γ-Ray Background above 50 GeV with the Fermi Large Area Telescope.

Author

Ackermann, M., Ajello, M., Albert, A., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Bissaldi, E., Blandford, R. D., Bloom, E. D., Bonino, R., Bregeon, J., Britto, R. J., Bruel, P., Buehler, R., Caliandro, G. A., and Cameron, R. A.

Subjects
*GALACTIC cosmic rays, *BACKGROUND radiation, *LARGE astronomical telescopes
Abstract

The Fermi Large Area Telescope (LAT) Collaboration has recently released a catalog of 360 sources detected above 50 GeV (2FHL). This catalog was obtained using 80 months of data re-processed with Pass 8, the newest event-level analysis, which significantly improves the acceptance and angular resolution of the instrument. Most of the 2FHL sources at high Galactic latitude are blazars. Using detailed Monte Carlo simulations, we measure, for the first time, the source count distribution, dN/dS, of extragalactic γ-ray sources at E>50 GeV and find that it is compatible with a uclidean distribution down to the lowest measured source flux in the 2FHL (~8?10-12 ph cm-2s-1). We employ a one-point photon fluctuation analysis to constrain the behavior of dN/dS below the source detection threshold. Overall, the source count distribution is constrained over three decades in flux and found compatible with a broken power law with a break flux, Sb, in the range [8?10-12,1.5?10-11]??ph?cm-2?s-1 and power-law indices below and above the break of α2∊[1.60,1.75] and α1=2.49±0.12, respectively. Integration of dN/dS shows that point sources account for at least 86+16/14% of the total extragalactic γ-ray background. The simple form of the derived source count distribution is consistent with a single population (i.e., blazars) dominating the source counts to the minimum flux explored by this analysis. We estimate the density of sources detectable in blind surveys that will be performed in the coming years by the Cherenkov Telescope Array. [ABSTRACT FROM AUTHOR]

Published
2016
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12. Search for Cosmic-Ray Electron and Positron Anisotropies with Seven Years of Fermi Large Area Telescope Data.

Author

Abdollahi S, Ackermann M, Ajello M, Albert A, Atwood WB, Baldini L, Barbiellini G, Bellazzini R, Bissaldi E, Bloom ED, Bonino R, Bottacini E, Brandt TJ, Bruel P, Buson S, Caragiulo M, Cavazzuti E, Chekhtman A, Ciprini S, Costanza F, Cuoco A, Cutini S, D'Ammando F, de Palma F, Desiante R, Digel SW, Di Lalla N, Di Mauro M, Di Venere L, Donaggio B, Drell PS, Favuzzi C, Focke WB, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Giglietto N, Giordano F, Giroletti M, Green D, Guiriec S, Harding AK, Jogler T, Jóhannesson G, Kamae T, Kuss M, Larsson S, Latronico L, Li J, Longo F, Loparco F, Lubrano P, Magill JD, Malyshev D, Manfreda A, Mazziotta MN, Meehan M, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monzani ME, Morselli A, Negro M, Nuss E, Ohsugi T, Omodei N, Paneque D, Perkins JS, Pesce-Rollins M, Piron F, Pivato G, Principe G, Rainò S, Rando R, Razzano M, Reimer A, Reimer O, Sgrò C, Simone D, Siskind EJ, Spada F, Spandre G, Spinelli P, Strong AW, Tajima H, Thayer JB, Torres DF, Troja E, Vandenbroucke J, Zaharijas G, and Zimmer S

Abstract

The Large Area Telescope on board the Fermi Gamma-ray Space Telescope has collected the largest ever sample of high-energy cosmic-ray electron and positron events since the beginning of its operation. Potential anisotropies in the arrival directions of cosmic-ray electrons or positrons could be a signature of the presence of nearby sources. We use almost seven years of data with energies above 42 GeV processed with the Pass 8 reconstruction. The present data sample can probe dipole anisotropies down to a level of 10^{-3}. We take into account systematic effects that could mimic true anisotropies at this level. We present a detailed study of the event selection optimization of the cosmic-ray electrons and positrons to be used for anisotropy searches. Since no significant anisotropies have been detected on any angular scale, we present upper limits on the dipole anisotropy. The present constraints are among the strongest to date probing the presence of nearby young and middle-aged sources.

Published
2017
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13. Measurement of separate cosmic-ray electron and positron spectra with the fermi large area telescope.

Author

Ackermann M, Ajello M, Allafort A, Atwood WB, Baldini L, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bouvier A, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cecchi C, Charles E, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, de Angelis A, de Palma F, Dermer CD, Digel SW, do Couto E Silva E, Drell PS, Drlica-Wagner A, Favuzzi C, Fegan SJ, Ferrara EC, Focke WB, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier IA, Grove JE, Guiriec S, Gustafsson M, Hadasch D, Harding AK, Hayashida M, Hughes RE, Jóhannesson G, Johnson AS, Kamae T, Katagiri H, Kataoka J, Knödlseder J, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Llena Garde M, Longo F, Loparco F, Lovellette MN, Lubrano P, Madejski GM, Mazziotta MN, McEnery JE, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nakamori T, Nolan PL, Norris JP, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes JF, Ozaki M, Paneque D, Parent D, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Porter TA, Rainò S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Ritz S, Romani RW, Roth M, Sadrozinski HF, Sbarra C, Schalk TL, Sgrò C, Siskind EJ, Spandre G, Spinelli P, Strong AW, Takahashi H, Takahashi T, Tanaka T, Thayer JG, Thayer JB, Tibaldo L, Tinivella M, Torres DF, Tosti G, Troja E, Uchiyama Y, Usher TL, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite AP, Winer BL, Wood KS, Wood M, Yang Z, and Zimmer S

Abstract

We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting Earth's shadow, which is offset in opposite directions for opposite charges due to Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 and 200 GeV. We confirm that the fraction rises with energy in the 20-100 GeV range. The three new spectral points between 100 and 200 GeV are consistent with a fraction that is continuing to rise with energy.

Published
2012
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14. Constraining dark matter models from a combined analysis of Milky Way satellites with the Fermi Large Area Telescope.

Author

Ackermann M, Ajello M, Albert A, Atwood WB, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bregeon J, Brigida M, Bruel P, Buehler R, Burnett TH, Buson S, Caliandro GA, Cameron RA, Cañadas B, Caraveo PA, Casandjian JM, Cecchi C, Charles E, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, de Angelis A, de Palma F, Dermer CD, Digel SW, do Couto e Silva E, Drell PS, Drlica-Wagner A, Falletti L, Favuzzi C, Fegan SJ, Ferrara EC, 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, Guiriec S, Gustafsson M, Hadasch D, Hayashida M, Hays E, Hughes RE, Jeltema TE, Jóhannesson G, Johnson RP, Johnson AS, Kamae T, Katagiri H, Kataoka J, Knödlseder J, Kuss M, Lande J, Latronico L, Lionetto AM, Llena Garde M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Mazziotta MN, McEnery JE, Mehault J, Michelson PF, Mitthumsiri W, Mizuno T, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Naumann-Godo M, Norris JP, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes JF, Ozaki M, Paneque D, Parent D, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Porter TA, Profumo S, Rainò S, Razzano M, Reimer A, Reimer O, Ritz S, Roth M, Sadrozinski HF, Sbarra C, Scargle JD, Schalk TL, Sgrò C, Siskind EJ, Spandre G, Spinelli P, Strigari L, Suson DJ, Tajima H, Takahashi H, Tanaka T, Thayer JG, Thayer JB, Thompson DJ, Tibaldo L, Tinivella M, Torres DF, Troja E, Uchiyama Y, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite AP, Wang P, Winer BL, Wood KS, Wood M, Yang Z, Zimmer S, Kaplinghat M, and Martinez GD

Abstract

Satellite galaxies of the Milky Way are among the most promising targets for dark matter searches in gamma rays. We present a search for dark matter consisting of weakly interacting massive particles, applying a joint likelihood analysis to 10 satellite galaxies with 24 months of data of the Fermi Large Area Telescope. No dark matter signal is detected. Including the uncertainty in the dark matter distribution, robust upper limits are placed on dark matter annihilation cross sections. The 95% confidence level upper limits range from about 10(-26)  cm3  s(-1) at 5 GeV to about 5×10(-23)   cm3  s(-1) at 1 TeV, depending on the dark matter annihilation final state. For the first time, using gamma rays, we are able to rule out models with the most generic cross section (∼3×10(-26)  cm3  s(-1) for a purely s-wave cross section), without assuming additional boost factors.

Published
2011
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15. Measurement of the cosmic ray e+ +e- spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope.

Author

Abdo AA, Ackermann M, Ajello M, Atwood WB, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Battelino M, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bogaert G, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Caliandro GA, Cameron RA, Caraveo PA, Carlson P, Casandjian JM, Cecchi C, Charles E, Chekhtman A, Cheung CC, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky LR, Conrad J, Cutini S, Dermer CD, de Angelis A, de Palma F, Digel SW, Di Bernardo G, do Couto E Silva E, Drell PS, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Focke WB, Frailis M, Fukazawa Y, Funk S, Fusco P, Gaggero D, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giordano F, Glanzman T, Godfrey G, Grasso D, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Hanabata Y, Harding AK, Hartman RC, Hayashida M, Hays E, Hughes RE, Jóhannesson G, Johnson AS, Johnson RP, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kocevski D, Kuehn F, Kuss M, Lande J, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Makeev A, Massai MM, Mazziotta MN, McConville W, McEnery JE, Meurer C, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Moretti E, Morselli A, Moskalenko 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, Pohl M, Porter TA, Profumo S, Rainò S, Rando R, Razzano M, 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, Sellerholm A, Sgrò C, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Stephens TE, Strickman MS, Strong AW, Suson DJ, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer JB, 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, Wallace E, Wang P, Winer BL, Wood KS, Ylinen T, and Ziegler M

Abstract

Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m;{2} sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E-3.0 and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.

Published
2009
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