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arXiv · 1706.08454

The Infrared Medium-deep Survey. III. Survey of Luminous Quasars at 4.7 $\leq$ z $\leq$ 5.4

Yiseul Jeon·Myungshin Im·Dohyeong Kim·Yongjung Kim·Hyunsung David Jun·Soojong Pak·Yoon Chan Taak·Giseon Baek·Changsu Choi·Nahyun Choi·Jueun Hong·Minhee Hyun·Tae-Geun Ji·Marios Karouzos·Duho Kim·Jae-Woo Kim·Ji Hoon Kim·Minjin Kim·Sanghyuk Kim·Hye-In Lee·Seong-Kook Lee·Won-Kee Park·Woojin Park·Yongmin Yoon
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Abstract

We present our first results of the survey for high redshift quasars at $5 \lesssim {\rm z} \lesssim 5.7$. The search for quasars in this redshift range has been known to be challenging due to limitations of filter sets used in previous studies. We conducted a quasar survey for two specific redshift ranges, 4.60 $\leq$ z $\leq$ 5.40 and 5.50 $\leq$ z $\leq$ 6.05, using multi-wavelength data that include observations using custom-designed filters, $is$ and $iz$. Using these filters and a new selection technique, we were able to reduce the fraction of interlopers. Through optical spectroscopy, we confirmed seven quasars at 4.7 $\leq$ z $\leq$ 5.4 with $-27.4 < M_{1450} < -26.4$ which were discovered independently by another group recently. We estimated black hole masses and Eddington ratios of four of these quasars from optical and near-infrared spectra, and found that these quasars are undergoing nearly Eddington-limited accretion which is consistent with the rapid growth of supermassive black holes in luminous quasars at z $\sim$ 5.

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Yiseul Jeon, Myungshin Im, Dohyeong Kim, Yongjung Kim, Hyunsung David Jun, Soojong Pak, Yoon Chan Taak, Giseon Baek, Changsu Choi, Nahyun Choi, Jueun Hong, Minhee Hyun, Tae-Geun Ji, Marios Karouzos, Duho Kim, Jae-Woo Kim, Ji Hoon Kim, Minjin Kim, Sanghyuk Kim, Hye-In Lee, Seong-Kook Lee, Won-Kee Park, Woojin Park, Yongmin Yoon. 2017-06-26. The Infrared Medium-deep Survey. III. Survey of Luminous Quasars at 4.7 $\leq$ z $\leq$ 5.4. https://doi.org/10.3847/1538-4365/aa7de5

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