ASCA observations of the Seyfert 1 galaxies Mrk1040 and MS0225.5+3121

Abstract

We present {\it ASCA} observations of the Seyfert 1 galaxies Mrk~1040 and MS~0225.5+3121. Mrk~1040 was found to have decreased in flux by almost a factor of 4 since an {\it EXOSAT} observation 10\,years ago. The energy spectrum of Mrk~1040 displays complexity both at soft energies (below 0.8\thinspace keV) and at hard energies (6--7\thinspace keV). The latter is readily interpreted as fluorescent K$\alpha$ emission from cold iron expected when the primary X-ray source illuminates cold optically-thick material. This line is both broad (with FWHM 16\,000--70\,000 km\,s${}^{-1}$) and strong (equivalent width $\sim 550\pm 250$\, eV) suggesting that it originates from material close to the compact object with non-solar abundances. Abundance effects on the equivalent width of such a line are investigated via Monte Carlo simulations. We find that strong lines can be produced with physically plausible abundances. The effect of abundances on the associated reflection continuum is also discussed. The soft spectral complexity implies either a strong soft excess together with intrinsic absorption, or a complex absorber. Various models for the nature of such a complex absorber are discussed. MS~0225.5+3121 shows no evidence for any variability and has a spectrum that is well described by a power law with Galactic absorption.

8 pages (including figures) uuencoded compressed Postscript file. Submitted to Monthly Notices of the Royal Astronomical Society

Cited by in corpus (19)

• The Nuclear Spectroscopic Telescope Array (NuSTAR) Mission
• ASCA observations of Seyfert 1 galaxies: II. Relativistic Iron K-alpha emission
• X-ray Spectral Properties of the BAT AGN Sample
• Iron fluorescence from within the innermost stable orbit of black hole accretion disks
• Spectral Analysis of 1H0707-495 with XMM-Newton
• A Monte Carlo Markov Chain based investigation of black hole spin in the active galaxy NGC3783
• Hard X-Ray Spectra of Broad-Line Radio Galaxies from the Rossi X-Ray Timing Explorer
• First Constraints on Iron Abundance versus Reflection Fraction from the Seyfert~1 Galaxy MCG--6-30-15
• Fitting the spectrum of the X-ray background: the effects of high metallicity absorption
• On the Origin of Broad Fe K alpha and Hi H alpha Lines in AGN
• The ASCA X-Ray Spectrum Of The Broad-Line Radio Galaxy Pictor A: A Simple Power Law With No Fe K-alpha Line
• Constraints on light bending and reflection from the hard X-ray background
• Are the Nuclei of Seyfert 2 Galaxies Viewed Face-On?
• Iron Line Spectroscopy of NGC4593 with XMM-Newton: Where is the Black Hole Accretion Disk?
• On the influence of resonant absorption on the iron emission line profiles from accreting black holes
• POLARIX: a pathfinder mission of X-ray polarimetry
• Correlation between relativistic reflection fraction and photon index in NuSTAR sample of Seyfert 1 AGN
• BeppoSAX Observations of the Seyfert-2 Galaxies NGC 7172 and ESO 103-G35
• Soft time lags in the X-ray emission of Mrk 1040