Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2018 Dec 14;121(24):241101.
doi: 10.1103/PhysRevLett.121.241101.

Unresolved Gamma-Ray Sky Through Its Angular Power Spectrum

Affiliations
Free article

Unresolved Gamma-Ray Sky Through Its Angular Power Spectrum

M Ackermann et al. Phys Rev Lett. .
Free article

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 Letter 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 ∼3.7σ 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±0.23 and 1.86±0.15.

Similar articles

  • Spectrum of the isotropic diffuse gamma-ray emission derived from first-year Fermi Large Area Telescope data.
    Abdo AA, Ackermann M, Ajello M, Atwood WB, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cavazzuti E, Cecchi C, Celik O, 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, Drlica-Wagner A, Dubois R, Dumora D, Farnier C, Favuzzi C, Fegan SJ, Focke WB, Fortin P, Frailis M, Fukazawa Y, Funk S, Fusco P, Gaggero D, Gargano F, Gasparrini D, Gehrels N, Germani S, Giebels B, Giglietto N, Giommi P, Giordano F, Glanzman T, Godfrey G, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Gustafsson M, Hanabata Y, Harding AK, Hayashida M, Hughes RE, Itoh R, Jackson MS, Jóhannesson G, Johnson AS, Johnson RP, Johnson TJ, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kocian ML, 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, 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, Nolan PL, Norris JP, Nuss E, Ohsugi T, Omodei N, Orlando E, Ormes JF, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter TA, Rainò S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rochester LS, Rodriguez AY, Roth M, Ryde F, Sadrozinski HF, Sanchez D, Sander A, Saz Parkinson PM, Scargle JD, Sellerholm A, Sgrò C, Shaw MS, Siskind EJ, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Strickman MS, Strong AW, Suson DJ, Tajima H, Takahashi H, Takahashi T, Tanaka T, Thayer JB, Thayer JG, Thompson DJ, Tibaldo L, 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; Fermi LAT Collaboration. Abdo AA, et al. Phys Rev Lett. 2010 Mar 12;104(10):101101. doi: 10.1103/PhysRevLett.104.101101. Epub 2010 Mar 8. Phys Rev Lett. 2010. PMID: 20366411
  • Resolving the Extragalactic γ-Ray Background above 50 GeV with the Fermi Large Area Telescope.
    Ackermann M, Ajello M, Albert A, Atwood WB, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Bissaldi E, Blandford RD, Bloom ED, Bonino R, Bregeon J, Britto RJ, Bruel P, Buehler R, Caliandro GA, Cameron RA, Caragiulo M, Caraveo PA, Cavazzuti E, Cecchi C, Charles E, Chekhtman A, Chiang J, Chiaro G, Ciprini S, Cohen-Tanugi J, Cominsky LR, Costanza F, Cutini S, D'Ammando F, de Angelis A, de Palma F, Desiante R, Digel SW, Di Mauro M, Di Venere L, Domínguez A, Drell PS, Favuzzi C, Fegan SJ, Ferrara EC, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Giglietto N, Giommi P, Giordano F, Giroletti M, Godfrey G, Green D, Grenier IA, Guiriec S, Hays E, Horan D, Iafrate G, Jogler T, Jóhannesson G, Kuss M, La Mura G, Larsson S, Latronico L, Li J, Li L, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Madejski GM, Magill J, Maldera S, Manfreda A, Mayer M, Mazziotta MN, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Negro M, Nuss E, Ohsugi T, Okada C, Omodei N, Orlando E, Ormes JF, Paneque D, Perkins JS, Pesce-Rollins M, Petrosian V, Piron F, Pivato G, Porter TA, Rainò S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reposeur T, Romani RW, Sánchez-Conde M, Schmid J, Schulz A, Sgrò C, Simone D, Siskind EJ, Spada F, Spandre G, Spinelli P, Suson DJ, Takahashi H, Thayer JB, Tibaldo L, Torres DF, Troja E, Vianello G, Yassine M, Zimmer S. Ackermann M, et al. Phys Rev Lett. 2016 Apr 15;116(15):151105. doi: 10.1103/PhysRevLett.116.151105. Epub 2016 Apr 14. Phys Rev Lett. 2016. PMID: 27127954
  • Fermi large area telescope measurements of the diffuse gamma-ray emission at intermediate galactic latitudes.
    Abdo AA, Ackermann M, Ajello M, Anderson B, Atwood WB, Axelsson M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Baughman BM, Bechtol K, Bellazzini R, Berenji B, Blandford RD, Bloom ED, Bonamente E, Borgland AW, Bregeon J, Brez A, Brigida M, Bruel P, Burnett TH, 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, Dereli H, Dermer CD, de Angelis A, de Palma F, Digel SW, Di Bernardo G, Dormody M, do Couto e Silva E, Drell PS, Dubois R, Dumora D, Edmonds Y, Farnier C, Favuzzi C, Fegan SJ, Focke WB, Frailis M, Fukazawa Y, Funk S, Fusco P, Gaggero D, Gargano F, 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, Jóhannesson G, Johnson AS, Johnson RP, Johnson TJ, Johnson WN, Kamae T, Katagiri H, Kataoka J, Kawai N, Kerr M, Knödlseder J, Kocian ML, Kuehn F, Kuss M, Lande J, Latronico L, 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, Nolan PL, Nuss E, Ohsugi T, Okumura A, Omodei N, Orlando E, Ormes JF, Paneque D, Panetta JH, Parent D, Pelassa V, Pepe M, Pesce-Rollins M, Piron F, Porter TA, Rainò S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Rodriguez AY, Roth M, Ryde F, Sadrozinski HF, Sanchez D, Sander A, Saz Parkinson PM, Scargle JD, Sellerholm A, Sgrò C, Smith DA, Smith PD, Spandre G, Spinelli P, Starck JL, Stecker FW, Striani E, Strickman MS, Strong AW, Suson DJ, Tajima H, Takahashi H, Tanaka T, Thayer JB, Thayer JG, Thompson DJ, Tibaldo L, 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; Fermi LAT Collaboration. Abdo AA, et al. Phys Rev Lett. 2009 Dec 18;103(25):251101. doi: 10.1103/PhysRevLett.103.251101. Epub 2009 Dec 16. Phys Rev Lett. 2009. PMID: 20366246
  • Evidence for Unresolved γ-Ray Point Sources in the Inner Galaxy.
    Lee SK, Lisanti M, Safdi BR, Slatyer TR, Xue W. Lee SK, et al. Phys Rev Lett. 2016 Feb 5;116(5):051103. doi: 10.1103/PhysRevLett.116.051103. Epub 2016 Feb 4. Phys Rev Lett. 2016. PMID: 26894697
  • In Vivo Observations of Rapid Scattered Light Changes Associated with Neurophysiological Activity.
    Rector DM, Yao X, Harper RM, George JS. Rector DM, et al. In: Frostig RD, editor. In Vivo Optical Imaging of Brain Function. 2nd edition. Boca Raton (FL): CRC Press/Taylor & Francis; 2009. Chapter 5. In Vivo Optical Imaging of Brain Function. 2nd edition. 2009. PMID: 26844322 Free Books & Documents. Review.
See all similar articles
Feedback