2004/02/11 by D. Grupe, S. Mathur, Smita Mathur +1 · 5 citations
Physics and Astronomy · #Active galactic nucleus #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #EPIC #Emission spectrum #Galaxies: Formation, Evolution, Phenomena #Galaxy #Light curve #Line (geometry) #Optics #Physics #Polarization (electrochemistry) #ROSAT #Spectral line #X-ray #astro-ph
paper · pdf · doi:10.1086/421002
published as Astron.J. 127 (2004) 3161 · Submitted to Aj, 11 pages, 8 figues
arxiv created 2004/02/11 · openalex publication_date 2004/06/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report the results of an XMM-Newton observation of the narrow-line Seyfert 1 galaxy Mrk 1239. This optically highly polarized AGN has one of the steepest X-ray spectra found in AGNs, with α X = +3.0 based on ROSAT PSPC data. The XMM-Newton EPIC pn and MOS data confirm this steep X-ray spectrum. The pn data are best fitted by a power law with a partial-covering absorption model suggesting two light paths between the continuum source and the observer, one indirect scattered one, which is less absorbed, and a highly absorbed direct light path. This result agrees with the wavelength-dependent degree of polarization in the optical/UV band. Residuals in the X-ray spectra of all three XMM-Newton EPIC detectors around 0.9 keV suggest the presence of an emission-line feature, most likely the Ne IX triplet. The detection of Ne IX and the nondetection of O VII/O VIII suggest a supersolar Ne/O ratio.