North Ecliptic Pole multi-wavelength survey : new optical data with Hyper Suprime-Cam and near-future prospects with eROSITA

Nagisa Oi; Hideo Matsuhara; Tomotsugu Goto; Yousuke Utsumi; Rieko Momose; Ting-Chi Huang; Yoshiki Toba; Myungshin Im; Hyung Mok Lee; Seong Jin Kim; Takamitsu Miyaji; Mirko Krumpe; Kazumi Murata; Youichi Ohyama; Steve Serjeant; Chris Pearson; Takao Nakagawa; Takehiko Wada; Toshinobu Takagi; Shuji Matsuura; Ayano Shogaki; NEP team

arXiv · 1712.01843

North Ecliptic Pole multi-wavelength survey : new optical data with Hyper Suprime-Cam and near-future prospects with eROSITA

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Abstract

The AKARI North Ecliptic Pole (NEP) survey consists of two survey projects: NEP-Deep (0.5 sq.deg) and NEP-Wide (5.4 sq.deg), providing with tens of thousands of galaxies. A continuous filter coverage in the mid-infrared wavelengths (7, 9, 11, 15, 18 and 24 $\mu$m) is unique to diagnose the contributions from dusty star-formation activity and AGNs. Here we present current status focused on the newly obtained optical images and near-future prospects with a new X-ray telescope. Hyper Suprime-Cam on Subaru telescope is a gigantic optical camera with huge Field of View (FoV). Thanks to the wide FoV, we successfully obtained deep optical images at g, r, i, z and Y-bands covering most of the NEP-Wide field. Using the deep optical images, we identified over 5000 optical counterparts of the mid-IR sources, presumably deeply obscured galaxies in NEP-Wide field. We also investigated properties of these infrared sources with SED-fitting. eROSITA, to be launched early 2018, is a new all-sky X-ray survey telescope, and expected to conduct ultra deep 2-10 keV imaging toward NEP. We expect unprecedentedly numerous Compton-thick AGN candidates when combined with the multi-wavelength data in NEP region.

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Nagisa Oi, Hideo Matsuhara, Tomotsugu Goto, Yousuke Utsumi, Rieko Momose, Ting-Chi Huang, Yoshiki Toba, Myungshin Im, Hyung Mok Lee, Seong Jin Kim, Takamitsu Miyaji, Mirko Krumpe, Kazumi Murata, Youichi Ohyama, Steve Serjeant, Chris Pearson, Takao Nakagawa, Takehiko Wada, Toshinobu Takagi, Shuji Matsuura, Ayano Shogaki, NEP team. 2017-12-05. North Ecliptic Pole multi-wavelength survey : new optical data with Hyper Suprime-Cam and near-future prospects with eROSITA. https://arxiv.org/abs/1712.01843

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