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Related papers: On discrepancy between ATIC and Fermi data

200 papers

The diffuse Galactic gamma-ray data from the region of the Galactic Center has been collected by the LAT instrument on the Fermi Gamma-Ray Space Telescope. In this paper we argue that it may be able to provide an unambiguous evidence of…

High Energy Astrophysical Phenomena · Physics 2009-09-09 Leszek Roszkowski , Yue-Lin Sming Tsai

The Vela pulsar is the brightest persistent source in the GeV sky and thus is the traditional first target for new gamma-ray observatories. We report here on initial Fermi Large Area Telescope observations during verification phase pointed…

Astrophysics · Physics 2009-11-13 A. A. Abdo

Since the PAMELA results on the "anomalously" high positron fraction and the lack of antiproton excess in our Galaxy, there has been a tremendous number of studies advocating new types of dark matter, with larger couplings to electrons than…

High Energy Physics - Phenomenology · Physics 2014-11-20 Celine Boehm , Timur Delahaye , Pierre Salati , Florian Staub , Ritesh K. Singh

We search for the presence of double gamma-ray line from unassociated Fermi-LAT sources including detailed Monte Carlo simulations to study its global statistical significance. Applying the Su & Finkbeiner selection criteria for high-energy…

High Energy Astrophysical Phenomena · Physics 2012-08-10 Andi Hektor , Martti Raidal , Elmo Tempel

We present an overview of precise pulsar timing using data from the Large Area Telescope (LAT) on Fermi. We describe the analysis techniques including a maximum likelihood method for determining pulse times of arrival from unbinned photon…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Paul S. Ray , Matthew Kerr , Damien Parent , the Fermi PSC

Recent claims of a line in the Fermi-LAT photon spectrum at 130 GeV are suggestive of dark matter annihilation in the galactic center and other dark matter-dominated regions. If the Fermi feature is indeed due to dark matter annihilation,…

High Energy Physics - Phenomenology · Physics 2015-06-11 Yang Bai , Jessie Shelton

Recently PAMELA collaboration published the cosmic nuclei and electron spectra with high precision, together with the cosmic antiproton data updated, and the Fermi-LAT collaboration also updated the measurement of the total $e^+e^-$…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-09 Jie Liu , Qiang Yuan , Xiao-Jun Bi , Hong Li , Xinmin Zhang

Our recent claims of a Galactic center feature in Fermi-LAT data at approximately 130 GeV have prompted an avalanche of papers proposing explanations ranging from dark matter annihilation to exotic pulsar winds. Because of the importance of…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Douglas P. Finkbeiner , Meng Su , Christoph Weniger

4FGL J1015.5-6030 is an unidentified Fermi-LAT source hosting a bright, extended X-ray source whose X-ray spectrum is consistent with that of a young pulsar, yet no pulsations have been found. Here we report on XMM-Newton timing and Chandra…

High Energy Astrophysical Phenomena · Physics 2023-07-12 Jeremy Hare , Oleg Kargaltsev , George Younes , George G. Pavlov , Igor Volkov

Using 43 months of public gamma-ray data from the Fermi Large Area Telescope, we find in regions close to the Galactic center at energies of 130 GeV a 4.6 sigma excess that is not inconsistent with a gamma-ray line from dark matter…

High Energy Astrophysical Phenomena · Physics 2015-06-11 Christoph Weniger

We isolated the anomalous part of the cosmic electron-positron flux within a Bayesian likelihood analysis. Using 219 recent cosmic ray spectral data points, we inferred the values of selected cosmic ray propagation parameters. In the…

High Energy Astrophysical Phenomena · Physics 2012-04-25 Katie Auchettl , Csaba Balázs

We report the results of a cross-match study between the hard X-ray and GeV gamma-ray catalogs, by making use of the latest 105-month Swift-BAT and 10-yr Fermi-LAT catalogs, respectively. The spatial cross-matching between the two catalogs…

High Energy Astrophysical Phenomena · Physics 2021-07-26 Naomi Tsuji , Hiroki Yoneda , Yoshiyuki Inoue , Tsuguo Aramaki , Georgia Karagiorgi , Reshmi Mukherjee , Hirokazu Odaka

The Fermi Large Area Telescope (LAT) has provided the most detailed view to date of the emission towards the Galactic centre (GC) in high-energy gamma-rays. This paper describes the analysis of data taken during the first 62 months of the…

High Energy Astrophysical Phenomena · Physics 2017-02-22 LAT Collaboration

Over the past few years, there has been a hint of the $\gamma$-ray excess observed by the Fermi-LAT satellite borne telescope from the regions surrounding the Galactic Centre at an energy range $\sim 1$-$3$ GeV. The nature of this excess…

High Energy Physics - Phenomenology · Physics 2016-03-21 Anirban Biswas

Very high-energy (VHE; E > 100 GeV) gamma-rays have been detected from a wide range of astronomical objects, such as SNRs, pulsars and pulsar wind nebulae, AGN, gamma-ray binaries, molecular clouds, and possibly star-forming regions as…

High Energy Astrophysical Phenomena · Physics 2010-01-19 P. H. Thomas Tam , Stefan Wagner , Omar Tibolla , Ryan Chaves

We describe an image-based method that uses two radio criteria, compactness and spectral index, to identify promising pulsar candidates among Fermi Large Area Telescope (LAT) unassociated sources. These criteria are applied to those radio…

We present a supersymmetric model with two dark matter (DM) components explaining the galactic positron excess observed by PAMELA/HEAT and ATIC/PPB-BETS: One is the conventional (bino-like) lightest supersymmetric particle (LSP) \chi, and…

High Energy Physics - Phenomenology · Physics 2009-08-01 Bumseok Kyae

We report the discovery of a statistically significant hardening in the Fermi-LAT $\gamma$-ray spectrum of Centaurus A's core, with the spectral index hardening from $\Gamma_{1}=2.73 \pm 0.02$ to $\Gamma_{1}=2.29 \pm 0.07$ at a break energy…

High Energy Astrophysical Phenomena · Physics 2017-11-16 Anthony M. Brown , Celine Bœhm , Jamie Graham , Thomas Lacroix , Paula Chadwick , Joe Silk

Aims. We use 5 years of Fermi-LAT data towards the Galactic-centre giant molecular cloud complex, Sagittarius B, to test questions of how well-mixed the Galactic component of cosmic rays are and what the level of the cosmic-ray sea in…

High Energy Astrophysical Phenomena · Physics 2015-08-12 Rui-zhi Yang , David I. Jones , Felix Aharonian

The isotropic gamma-ray background arises from the contribution of unresolved sources, including members of confirmed source classes and proposed gamma-ray emitters such as the radiation induced by dark matter annihilation and decay. Clues…