Fermi large area telescope measurements of the diffuse gamma-ray emission at intermediate galactic latitudes

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

doi:10.1103/PhysRevLett.103.251101

Fermi large area telescope measurements of the diffuse gamma-ray emission at intermediate galactic latitudes

Phys Rev Lett. 2009 Dec 18;103(25):251101. doi: 10.1103/PhysRevLett.103.251101. Epub 2009 Dec 16.

Authors

A A Abdo¹, M Ackermann, M Ajello, B Anderson, W B Atwood, M Axelsson, L Baldini, J Ballet, G Barbiellini, D Bastieri, B M Baughman, K Bechtol, R Bellazzini, B Berenji, R D Blandford, E D Bloom, E Bonamente, A W Borgland, J Bregeon, A Brez, M Brigida, P Bruel, T H Burnett, G A Caliandro, R A Cameron, P A Caraveo, J M Casandjian, C Cecchi, E Charles, A Chekhtman, C C Cheung, J Chiang, S Ciprini, R Claus, J Cohen-Tanugi, J Conrad, H Dereli, C D Dermer, A de Angelis, F de Palma, S W Digel, G Di Bernardo, M Dormody, E do Couto e Silva, P S Drell, R Dubois, D Dumora, Y Edmonds, C Farnier, C Favuzzi, S J Fegan, W B Focke, M Frailis, Y Fukazawa, S Funk, P Fusco, D Gaggero, F Gargano, N Gehrels, S Germani, B Giebels, N Giglietto, F Giordano, T Glanzman, G Godfrey, I A Grenier, M-H Grondin, J E Grove, L Guillemot, S Guiriec, Y Hanabata, A K Harding, M Hayashida, E Hays, R E Hughes, G Jóhannesson, A S Johnson, R P Johnson, T J Johnson, W N Johnson, T Kamae, H Katagiri, J Kataoka, N Kawai, M Kerr, J Knödlseder, M L Kocian, F Kuehn, M Kuss, J Lande, L Latronico, F Longo, F Loparco, B Lott, M N Lovellette, P Lubrano, G M Madejski, A Makeev, M N Mazziotta, W McConville, J E McEnery, C Meurer, P F Michelson, W Mitthumsiri, T Mizuno, A A Moiseev, C Monte, M E Monzani, A Morselli, I V Moskalenko, S Murgia, P L Nolan, E Nuss, T Ohsugi, A Okumura, N Omodei, E Orlando, J F Ormes, D Paneque, J H Panetta, D Parent, V Pelassa, M Pepe, M Pesce-Rollins, F Piron, T A Porter, S Rainò, R Rando, M Razzano, A Reimer, O Reimer, T Reposeur, S Ritz, A Y Rodriguez, M Roth, F Ryde, H F-W Sadrozinski, D Sanchez, A Sander, P M Saz Parkinson, J D Scargle, A Sellerholm, C Sgrò, D A Smith, P D Smith, G Spandre, P Spinelli, J-L Starck, F W Stecker, E Striani, M S Strickman, A W Strong, D J Suson, H Tajima, H Takahashi, T Tanaka, J B Thayer, J G Thayer, D J Thompson, L Tibaldo, D F Torres, G Tosti, A Tramacere, Y Uchiyama, T L Usher, V Vasileiou, N Vilchez, V Vitale, A P Waite, P Wang, B L Winer, K S Wood, T Ylinen, M Ziegler; Fermi LAT Collaboration

Affiliation

¹ Space Science Division, Naval Research Laboratory, Washington, DC 20375, USA.

PMID: 20366246
DOI: 10.1103/PhysRevLett.103.251101

Abstract

The diffuse galactic gamma-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray Observatory indicated excess gamma-ray emission greater, > or approximately equal to 1 GeV relative to diffuse galactic gamma-ray emission models consistent with directly measured CR spectra (the so-called "EGRET GeV excess"). The Large Area Telescope (LAT) instrument on the Fermi Gamma-Ray Space Telescope has measured the diffuse gamma-ray emission with improved sensitivity and resolution compared to EGRET. We report on LAT measurements for energies 100 MeV to 10 GeV and galactic latitudes 10 degrees < or = |b| < or = 20 degrees. The LAT spectrum for this region of the sky is well reproduced by a diffuse galactic gamma-ray emission model that is consistent with local CR spectra and inconsistent with the EGRET GeV excess.