Akihiro FURUZAWA, Akiko KUMADA, Yuzuru TAWARA and Kojun YAMASHITA
Abstract
Most of distant clusters of galaxies observed with ASCA show high plasma temperature, low metal abundance and smooth spherically symmetric surface brightness distribution. On the other hand, the existence of temperature gradient and very strong Fe-K line emission have been reported for some distant clusters of galaxies . Especially from A665, Fe-Kalpha and Kbeta lines are clearly detected. The ratio of He-like Fe-Kalpha to H-like Fe-Kalpha is well consistent with the predicted value with the plasma temperature derived from the continuum spectrum. The ratio of Kalpha to Kbeta seems to be smaller than the model prediction, though it is marginal because of statistical errors. The metal abundance derived from best-fit value of Fe-Kbeta line intensity is 3 times larger than that derived from Fe-Kalpha due to the strong Kbeta line intensity in comparison with Kalpha. For other distant clusters of galaxies the same tendency has been seen though photon statistics are poor.
|