DETECTION OF THE COSMIC FAR-INFRARED BACKGROUND IN AKARI DEEP FIELD SOUTH

Journal Article · Wed Aug 10 00:00:00 EDT 2011 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/737/1/2· OSTI ID:21580006

Matsuura, S; Shirahata, M; Kawada, M; Matsuhara, H; Nakagawa, T; Oyabu, S; Takagi, T ^[1]; Takeuchi, T T ^[2]; Burgarella, D ^[3]; Clements, D L ^[4]; Jeong, W -S ^[5]; Hanami, H ^[6]; Khan, S A ^[7]; Pearson, C P; White, G J ^[8]; Pollo, A ^[9]; Serjeant, S ^[10]

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1. Institute of Space and Astronautical Science, JAXA, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan)
2. Institute for Advanced Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan)
3. Astronome a l'Observatoire Astronomique Marseille Provence, Laboratorie d'Astrophysique de Marseille, Technopole Chateau-Gombert 38, rue Frederic Joliot-Curie, 13388 Marseille cedex 13 (France)
4. Physics Department, Imperial College London, Prince Consort Road, London SW7 2AZ (United Kingdom)
5. Space Science Division, Korea Astronomy and Space Science Institute, 61-1, Whaam-dong, Yuseong-gu, Deajeon 305-348 (Korea, Republic of)
6. Physics Section, Faculty of Humanities and Social Sciences, Iwate University (Japan)
7. Shanghai Key Lab for Astrophysics, Shanghai Normal University, Shanghai 200234 (China)
8. Space Science and Technology Department, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom)
9. Astronomical Observatory of the Jagiellonian University, ul. Orla 171, 30-244 Krakow (Poland)
10. Department of Physics and Astronomy, Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom)

We report new limits on the absolute brightness and spatial fluctuations of the cosmic infrared background (CIB) via the AKARI satellite. We carried out observations at 65, 90, 140, and 160 {mu}m as a cosmological survey in AKARI Deep Field South, which is one of the lowest cirrus regions with a contiguous area of the sky. After removing bright galaxies and subtracting zodiacal and Galactic foregrounds from the measured sky brightness, we successfully measured the CIB brightness and its fluctuations across a wide range of angular scales, from arcminutes to degrees. The measured CIB brightness is consistent with previous results reported from COBE data, but significantly higher than the lower limits at 70 and 160 {mu}m obtained via Spitzer from the stacking analysis of selected 24 {mu}m sources. The discrepancy with the Spitzer result is possibly due to a new galaxy population at high redshift obscured by hot dust or unknown diffuse emission. From a power spectrum analysis at 90 {mu}m, two components were identified: the CIB fluctuations with shot noise due to individual galaxies in a small angular scale from the beam size up to 10 arcminutes, and Galactic cirrus emission dominating at the largest angular scales of a few degrees. The overall shape of the power spectrum at 90 {mu}m is very similar to that at longer wavelengths, as observed by Spitzer and the Balloon-borne Large-Aperture Submillimeter Telescope (BLAST). Our power spectrum, with an intermediate angular scale of 10-30 arcminutes, gives a firm upper limit for galaxy clustering, which was found by Spitzer and BLAST. Moreover, the color of the CIB fluctuations, which is obtained by combining our data with the previous results, is as red as ultra-luminous infrared galaxies at high redshift. These galaxies are not likely to provide the majority of the CIB emission at 90 {mu}m, but are responsible for the fluctuations. Our results provide new constraints on the evolution and clustering properties of distant infrared galaxies and any diffuse emission from the early universe.

• OSTI ID: 21580006
• Journal Information: Astrophysical Journal, Vol. 737, Issue 1; Other Information: DOI: 10.1088/0004-637X/737/1/2; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BACKGROUND RADIATION
BIOLOGICAL EVOLUTION
BRIGHTNESS
COSMIC RADIATION
COSMIC RAY DETECTION
COSMOLOGY
EMISSION
FAR INFRARED RADIATION
FLUCTUATIONS
GALAXIES
GALAXY CLUSTERS
DETECTION
ELECTROMAGNETIC RADIATION
EVOLUTION
INFRARED RADIATION
IONIZING RADIATIONS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RADIATION DETECTION
RADIATIONS
VARIATIONS