Optical Identification of theASCALynx Deep Survey: An Association of Quasi‐Stellar Objects and a Supercluster at \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage[OT2,OT1]{fontenc} \newcommand\cyr{ \renewcommand\rmdefault{wncyr} \renewcommand\sfdefault{wncyss} \renewcommand\…

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 sixsources are identified with AGNs/QSOs at redshifts of 0.5-1.3. We also identifytwo 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 clustersand several groups of galaxies are also placed at the same redshift in thesurveyed field, and projected separations between the QSOs and the clusters are3-8 Mpc at the redshift.