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arXiv · 2112.05350

Polarization spectrum of near infrared zodiacal light observed with CIBER

Kohji Takimoto·Toshiaki Arai·Shuji Matsuura·James J. Bock·Asantha Cooray·Richard M. Feder·Phillip M. Korngut·Alicia Lanz·Dae Hee Lee·Toshio Matsumoto·Chi H. Nguyen·Yosuke Onishi·Kei Sano·Mai Shirahata·Aoi Takahashi·Kohji Tsumura·Michael Zemcov
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Abstract

We report the first measurement of the zodiacal light (ZL) polarization spectrum in the near-infrared between 0.8 and 1.8 $μ$m. Using the low-resolution spectrometer (LRS) on board the Cosmic Infrared Background Experiment (CIBER), calibrated for absolute spectrophotometry and spectropolarimetry, we acquire long-slit polarization spectral images of the total diffuse sky brightness towards five fields. To extract the ZL spectrum, we subtract contribution of other diffuse radiation, such as the diffuse galactic light (DGL), the integrated star light (ISL), and the extragalactic background light (EBL). The measured ZL polarization spectrum shows little wavelength dependence in the near-infrared and the degree of polarization clearly varies as a function of the ecliptic coordinates and solar elongation. Among the observed fields, the North Ecliptic Pole shows the maximum degree of polarization of $\sim$ 20$\%$, which is consistent with an earlier observation from the Diffuse Infrared Background Experiment (DIRBE) aboard on the Cosmic Background Explorer (COBE). The measured degree of polarization and its solar elongation dependence are reproduced by the empirical scattering model in the visible band and also by the Mie scattering model for large absorptive particles, while the Rayleigh scattering model is ruled out. All of our results suggest that the interplanetary dust is dominated by large particles.

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Kohji Takimoto, Toshiaki Arai, Shuji Matsuura, James J. Bock, Asantha Cooray, Richard M. Feder, Phillip M. Korngut, Alicia Lanz, Dae Hee Lee, Toshio Matsumoto, Chi H. Nguyen, Yosuke Onishi, Kei Sano, Mai Shirahata, Aoi Takahashi, Kohji Tsumura, Michael Zemcov. 2021-12-10. Polarization spectrum of near infrared zodiacal light observed with CIBER. https://doi.org/10.3847/1538-4357%2Fac416f

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