Results 51 to 60 of about 20,416 (210)

Detection of Gamma-Ray Emission from the Starburst Galaxies M82 and NGC 253 with the Large Area Telescope on Fermi

, 2009
We report the detection of high-energy gamma-ray emission from two starburst galaxies using data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope.
Abdo, AA, Ackermann, M, Ajello, M, Atwood, WB, Axelsson, M, Baldini, L, Ballet, J, Barbiellini, G, Bastieri, D, Bechtol, K, Bellazzini, R, Berenji, B, Bloom, ED, Bonamente, E, Borgland, AW, Bregeon, J, Brez, A, Brigida, M, Bruel, P, Burnett, TH, Caliandro, GA, Cameron, RA, Caraveo, PA, Casandjian, JM, Cavazzuti, E, Cecchi, C, Charles, E, Chekhtman, A, Cheung, CC, Chiang, J, Ciprini, S, Claus, R, CohenTanugi, J, Conrad, J, De Palma, F, Deangelis, A, Dermer, CD, Digel, SW, Do Couto E Silva, E, Drell, PS, DrlicaWagner, A, Dubois, R, Dumora, D, Farnier, C, Favuzzi, C, Fegan, SJ, Focke, WB, Foschini, L, Frailis, M, 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, Hughes, RE, Johnson, AS, Johnson, RP, Johnson, WN, Jóhannesson, G, Kamae, T, Katagiri, H, Kataoka, J, Kawai, N, Kerr, M, Knödlseder, J, Kocian, ML, Kuss, M, Lande, J, Latronico, L, LemoineGoumard, M, Longo, F, Loparco, F, Lott, B, Lovellette, MN, Lubrano, P, Madejski, GM, Makeev, A, Mazziotta, MN, Mcconville, W, Mcenery, JE, Meurer, C, 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, Ohsugi, T, Omodei, N, Orlando, E, Ormes, JF, Ozaki, M, Paneque, D, Panetta, JH, Parent, D, Pelassa, V, Pepe, M, PesceRollins, M, Piron, F, Porter, TA, Rainò, S, Rando, R, Razzano, M, Reimer, A, Reimer, O, Reposeur, T, Ritz, S, Rodriguez, AY, Romani, RW, Roth, M, Ryde, F, Sadrozinski, HFW, Sander, A, Saz Parkinson, PM, Scargle, JD, Sellerholm, A, Sgrò, C, Shaw, MS, Smith, DA, Smith, PD, Spandre, G, Spinelli, P, Strickman, MS, Strong, AW, Suson, DJ, Takahashi, H, Tanaka, T, Thayer, JB, Thayer, JG, Thompson, DJ, Tibaldo, L, Tibolla, O, Torres, DF, Tosti, G, Tramacere, A, Uchiyama, Y, Usher, TL, Vasileiou, V, Vilchez, N, Vitale, V, Waite, AP, Wang, P, Winer, BL, Wood, KS, Ylinen, T, Ziegler, M, Çelik, O   +169 more
core   +3 more sources

Poisson denoising on the sphere: application to theFermigamma ray space telescope [PDF]

Astronomy and Astrophysics, 2010
16 pages, 8 ...
Schmitt, J., Starck, J.L., Casandjian, J.M., Fadili, J., Grenier, I.   +4 more
openaire   +4 more sources

Quasi‐Constant Time Gap in Multiple Rings of Elves

Earth and Space Science, Volume 12, Issue 10, October 2025.
Abstract We present evidence that the time delay between the multiple rings of elves is not caused by the ground reflection of the electromagnetic pulse produced by intracloud lightning. To investigate temporal differences of multi‐elves, we analyzed data from four storms occurring at various times and distances from the Pierre Auger Observatory in ...
The Pierre Auger Collaboration
wiley   +1 more source

Upper limit on the axion-photon coupling from Markarian 421

Physics Letters B
Markarian421 is a well-known nearby BL Lac blazar at the redshift z=0.031. Many previous works were investigated to constrain the axion-photon coupling from its TeV gamma-ray observations, showing the upper limit on the coupling constant gaγ≲2.0×10−11GeV−
Hai-Jun Li, Wei Chao, Yu-Feng Zhou
doaj   +1 more source

Relativistic Jets in Gamma-Ray-Emitting Narrow-Line Seyfert 1 Galaxies

Galaxies, 2019
Before the launch of the Fermi Gamma-ray Space Telescope satellite only two classes of active galactic nuclei (AGN) were known to generate relativistic jets and thus to emit up to the γ -ray energy range: blazars and radio galaxies, both hosted
Filippo D’Ammando
doaj   +1 more source

On the Gamma-Ray Emission of the Andromeda Galaxy M31

The Astrophysical Journal Letters, 2023
Using the γ -ray data obtained with the Large Area Telescope on board the Fermi Gamma-ray Space Telescope (Fermi) for ∼14 yr, we examine the high-energy emission emanating from the center of the Andromeda galaxy M31.
Yi Xing, Zhongxiang Wang, Dong Zheng, Jie Li   +3 more
doaj   +1 more source

Pre-burst events of gamma-ray bursts with light speed variation

Physics Letters B, 2021
Previous researches on high-energy photon events from gamma-ray bursts (GRBs) suggest a light speed variation v(E)=c(1−E/ELV) with ELV=3.6×1017 GeV, together with a pre-burst scenario that hight-energy photons come out about 10 seconds earlier than low ...
Jie Zhu, Bo-Qiang Ma
doaj   +1 more source

The multi-faceted synergy between Swift and Fermi in radio-loud AGN studies

, 2015
Since its launch in 2008 June, the Fermi Gamma-ray Space Telescope has opened a new era in high-energy astrophysics. The unprecedented sensitivity, angular resolution and effective area of the Large Area Telescope on board Fermi, together with the nearly
D'Ammando, F.
core   +1 more source

2‐D Speed Profile of Negative Cloud‐to‐Ground Lightning Flashes With TGF Emissions

Journal of Geophysical Research: Atmospheres, Volume 130, Issue 15, 16 August 2025.
Abstract We present the two‐dimensional (2‐D) speed profile of six stepped leaders with terrestrial gamma‐ray flashes (TGFs) (observed in 2021 (Abbasi et al., 2024, https://doi.org/10.1029/2024jd041260) and 2022 (Kieu et al., 2024, https://doi.org/10.1029/2024jd041720)) and 94 stepped leaders without TGFs (detected in 2021, 2022, 2023, and 2024). These
Ivan T. Cruz, Marcelo M. F. Saba, Rasha U. Abbasi, José Claudio O. Silva, Gabriel S. Diniz, Ny T. Kieu, Diego R. R. da Silva, Tagianne P. da Silva, Paola B. Lauria   +8 more
wiley   +1 more source

Model of gamma sky for the Fermi Gamma-ray Space Telescope (FGST) [PDF]

, 2010
A number of important parameters of cosmic-ray distribution, propagation, and interaction in the Milky Way can be predicted through the comparison of measured cosmic-ray and gamma-ray spectra to the spectra of simulated Galaxies. These predictions are made by altering the physical parameters governing Galaxy simulations until a best-fit set of ...
McLeod, Andrew, /UC, San Diego /SLAC /KIPAC, Menlo Park   +3 more
openaire   +2 more sources