A COMPARISON OF HARD X-RAY PHOTON INDICES AND IRON Kα EMISSION LINES IN X-RAY LUMINOUS NARROW- AND BROAD-LINE SEYFERT 1 GALAXIES

We use publicly available XMM-Newton data to systematically compare the hard X-ray photon indices, Gamma(2-10) (keV), and the iron K alpha emission lines of narrow-and broad-line Seyfert 1 (NLS1 and BLS1) galaxies. We compile a flux-limited (f(2-10) (keV) >= 1x10(-1)2 erg s(-1) cm(-2)) sample including 114 radio-quiet objects, with the 2-10 keV luminosity ranging from 10(41) to 10(45) erg s(-1). Our main results are: (1) NLS1s and BLS1s show similar luminosity distributions; (2) the weighted means of Gamma(2-10 keV) of NLS1s, BLS1s, and the total sample are 2.04+/-0.04, 1.74+/-0.02, and 1.84+/-0.02, respectively; a significant anti-correlation between Gamma(2-10 keV) and FWHMH beta suggests that Gamma(2-10 keV) > 2.0 may be taken to indicate the X-ray luminous NLS1 type; (3) the 6.4 keV narrow iron K alpha lines from NLS1s are generally weaker than that from BLS1s; this would indicate a smaller covering factor of the dusty tori in NLS1s if the line emission originates from the inner boundary region of the dusty torus in an active galactic nucleus; and (4) all the broadened iron K alpha lines with intrinsic width sigma > 0.5 keV correspond to FWHMH beta <= 4000 km s(-1).