T. Kii, O.R. Williams, T. Ohashi, H. Awaki K. Hayashida, H. Inoue, H. Kondo, K. Koyama, F. Makino, K. Makishima, R.D. Saxton, G.C. Stewart, S. Takano, Y. Tanaka and M.J.L. Turner

Abstract

This paper reports on the 2-10 keV spectrum of the quasar E1821 + 643, obtained with the large-area proportional counters aboard the Ginga spacecraft on two occasions: May 12-14, 1987 and September 27, 1988. The spectrum shows strong evidence for the presence of a redshifted iron K emission line of a 5.1 + or - 0.2 keV energy, and an observed equivalent width of 210 + or - 80 eV. The E1821 + 643 appeared to be embedded within a cluster of galaxies which could contribute part of the observed line. A possibility is suggested that iron emission lines may be a common feature in X-ray spectra of quasars.