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arXiv · 0706.0253

Detection of an H-alpha Emission Line on a Quasar, RX J1759.4+6638, at z=4.3 with AKARI

Shinki Oyabu·Takehiko Wada·Youichi Ohyama·Hideo Matsuhara·Toshinobu Takagi·Takao Nakagawa·Takashi Onaka·Naofumi Fujishiro·Daisuke Ishihara·Yoshifusa Ita·Hirokazu Kataza·Woojung Kim·Toshio Matsumoto·Hiroshi Murakami·Itsuki Sakon·Toshihiko Tanabe·Kazunori Uemizu·Munetaka Ueno·Fumihiko Usui·Hidenori Watarai·Kanae Haze
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Abstract

We report the detection of an H-alpha emission line in the low resolution spectrum of a quasar, RX J1759.4+6638, at a redshift of 4.3 with the InfraRed Camera (IRC) onboard the AKARI. This is the first spectroscopic detection of an H-alpha emission line in a quasar beyond z=4. The overall spectral energy distribution (SED) of RX J1759.4+6638 in the near- and mid-infrared wavelengths agrees with a median SED of the nearby quasars and the flux ratio of F(Ly-alpha)/F(H-alpha) is consistent with those of previous reports for lower-redshift quasars.

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Shinki Oyabu, Takehiko Wada, Youichi Ohyama, Hideo Matsuhara, Toshinobu Takagi, Takao Nakagawa, Takashi Onaka, Naofumi Fujishiro, Daisuke Ishihara, Yoshifusa Ita, Hirokazu Kataza, Woojung Kim, Toshio Matsumoto, Hiroshi Murakami, Itsuki Sakon, Toshihiko Tanabe, Kazunori Uemizu, Munetaka Ueno, Fumihiko Usui, Hidenori Watarai, Kanae Haze. 2007-06-02. Detection of an H-alpha Emission Line on a Quasar, RX J1759.4+6638, at z=4.3 with AKARI. https://doi.org/10.1093/pasj%2F59.sp2.s497

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