On the origin of near-infrared extragalactic background light anisotropy.
Extragalactic background light (EBL) anisotropy traces variations in the total production of photons over cosmic history and may contain faint, extended components missed in galaxy point-source surveys. Infrared EBL fluctuations have been attributed to primordial galaxies and black holes at the epoch of reionization (EOR) or, alternately, intrahalo light (IHL) from stars tidally stripped from their parent galaxies at low redshift. We report new EBL anisotropy measurements from a specialized sounding rocket experiment at 1.1 and 1.6 micrometers. The observed fluctuations exceed the amplitude from known galaxy populations, are inconsistent with EOR galaxies and black holes, and are largely explained by IHL emission. The measured fluctuations are associated with an EBL intensity that is comparable to the background from known galaxies measured through number counts and therefore a substantial contribution to the energy contained in photons in the cosmos.
Department of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA. Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109, USA.
Michael
M
Zemcov
Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA. Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA.
Joseph
J
Smidt
Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210, Japan. Department of Physics, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan.
Toshiaki
T
Arai
Department of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA. Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109, USA. jjb@astro.caltech.edu.
James
J
Bock
Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA.
Asantha
A
Cooray
Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA.
Yan
Y
Gong
Department of Physics and Astronomy, Seoul National University, Seoul 151-742, Korea.
Min Gyu
MG
Kim
Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109, USA. Department of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA.
Phillip
P
Korngut
Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, USA. Department of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, CA 91125, USA.
Anson
A
Lam
Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348, Korea.
Dae Hee
DH
Lee
Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210, Japan. Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 10617, Taiwan, Republic of China.
Toshio
T
Matsumoto
Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210, Japan.
Shuji
S
Matsuura
Korea Astronomy and Space Science Institute (KASI), Daejeon 305-348, Korea.
Uk Won
UW
Nam
Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA), Pasadena, CA 91109, USA.
Gael
G
Roudier
Frontier Research Institute for Interdisciplinary Science, Tohoku University, Sendai, Miyagi, 980-8578, Japan.
Kohji
K
Tsumura
Department of Space Astronomy and Astrophysics, Institute of Space and Astronautical Science (ISAS), Japan Aerospace Exploration Agency (JAXA), Sagamihara, Kanagawa 252-5210, Japan.
Takehiko
T
Wada