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Optical Identification of the ASCA Lynx Deep Survey: An Association of QSOs and a Supercluster at z=1.3?

Kouji Ohta·Masayuki Akiyama·Yoshihiro Ueda·Toru Yamada·Kouichiro Nakanishi·Gavin B. Dalton·Yasushi Ogasaka·Tsuneo Kii·Kiyoshi Hayashida
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Abstract

Results of optical identification of the ASCA Lynx deep survey are presented. Six X-ray sources are detected in the 2-7 keV band using the SIS in a 20'x20' field of view with fluxes larger than ~4x10^{-14} erg s-1 cm-2 in the band. Follow-up optical spectroscopic observations were made, and five out of six sources are identified with AGNs/QSOs at redshifts of 0.5-1.3. We also identify two more additional X-ray sources detected in a soft X-ray band with AGNs/QSOs. It is found that three QSOs identified are located at z~1.3. Two rich clusters and several groups of galaxies are also placed at the same redshift in the surveyed field, and projected separations between the QSOs and the clusters are 3-8 Mpc at the redshift.

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Kouji Ohta, Masayuki Akiyama, Yoshihiro Ueda, Toru Yamada, Kouichiro Nakanishi, Gavin B. Dalton, Yasushi Ogasaka, Tsuneo Kii, Kiyoshi Hayashida. 2003-08-05. Optical Identification of the ASCA Lynx Deep Survey: An Association of QSOs and a Supercluster at z=1.3?. https://doi.org/10.1086/378690

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