AKARI OBSERVATION OF THE SUB-DEGREE SCALE FLUCTUATION OF THE NEAR-INFRARED BACKGROUND

Journal Article · Fri Jul 10 04:00:00 EDT 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/807/2/140· OSTI ID:22522183

Seo, H. J.; Lee, Hyung Mok; Lee, Myung Gyoon ^[1]; Matsumoto, T. ^[2]; Jeong, W. -S.

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1. Department of Physics and Astronomy, Seoul National University, Seoul 151-742 (Korea, Republic of)
2. Institute of Astronomy and Astrophysics, Academia Sinica, Taipei 10617, Taiwan (China)

We report spatial fluctuation analysis of the sky brightness in the near-infrared from observations toward the north ecliptic pole (NEP) by the AKARI at 2.4 and 3.2 μm. As a follow-up study of our previous work on the Monitor field of AKARI, we used NEP deep survey data, which covered a circular area of about 0.4 square degrees, in order to extend fluctuation analysis at angular scales up to 1000″. We found residual fluctuation over the estimated shot noise at larger angles than the angular scale of the Monitor field. The excess fluctuation of the NEP deep field smoothly connects with that of the Monitor field at angular scales of a few hundred arcseconds and extends without any significant variation to larger angular scales up to 1000″. By comparing excess fluctuations at two wavelengths, we confirm a blue spectral feature similar to the result of the Monitor field. We find that the result of this study is consistent with Spitzer Space Telescope observations at 3.6 μm. The origin of the excess fluctuation in the near-infrared background remains to be determined, but we could exclude zodiacal light, diffuse Galactic light, and unresolved faint galaxies at low redshift based on the comparison with mid- and far-infrared brightness, ground-based near-infrared images.

• OSTI ID: 22522183
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 807; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BRIGHTNESS
COMPARATIVE EVALUATIONS
COSMIC DUST
DATA ANALYSIS
FLUCTUATIONS
GALAXIES
GALAXY CLUSTERS
IMAGES
NEAR INFRARED RADIATION
NOISE
RED SHIFT
SKY
SPACE
STARS
TELESCOPES
VISIBLE RADIATION
ZODIACAL LIGHT