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We investigate the origin of the soft X-ray excess emission from narrow-lineSeyfert 1 galaxies Akn564 and Mrk1044 using XMM-Newton observations. We findclear evidence for time delays between the soft and hard X-ray emission fromAkn564 based on a 100ks long observation. The variations in the 4-10keV bandlag behind that in the 0.2-0.5keV band by 1768+/-122s. The full band powerdensity spectrum (PDS) of Akn~564 has a break at ~1.2e-3Hz with power-lawindices of ~1 and ~3 below and above the break. The hard (3-10keV) band PDS isstronger and flatter than that in the soft (0.2-0.5keV) band. Based on a shortobservation of Mrk1044, we find no correlation between the 0.2-0.3keV and5-10keV bands at zero lag. These observations imply that the soft excess is notthe reprocessed hard X-ray emission. The high resolution spectrum of Akn564obtained with the RGS shows evidence for a highly ionized and another weaklyionized warm absorber medium. The smeared wind and blurred ionized reflectionmodels do not describe the pn data adequately. The spectrum is consistent witha complex model consisting of optically thick Comptonization in a cool plasmafor the soft excess and a steep power-law, modified by two warm absorber mediaas inferred from the RGS data and the foreground Galactic absorption. Thesmeared wind and optically thick Comptonization models both describe thespectrum of Mrk1044 satisfactorily, but the ionized reflection model requiresextreme parameters. The data suggest two component corona -- a cool, opticallythick corona for the soft excess and a hot corona for the power-law component.The existence of a break in the soft band PDS suggests a compact cool coronathat can either be an ionized surface of the inner disk or an inner opticallythick region coupled to a truncated disk.

An investigation of the origin of soft X-ray excess emission from Narrow-line Seyfert 1 galaxies Akn564 and Mrk1044