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The Role of Complex Ionized Absorber in the Soft X-ray Spectra of Intermediate PolarsIn magnetic Cataclysmic Variables (mCVs), X-ray radiation originates from the shock heated multi-temperature plasma in the post-shock region near the white dwarf surface. These X-rays are modified by a complex distribution of absorbers in the pre-shock region. The presence of photo-ionized lines and warm absorber features in the soft X-ray spectra of these mCVs suggests that these absorbers are ionized. We developed the ionized complex absorber model zxipab, which is represented by a power-law distribution of ionized absorbers in the pre-shock ow. Using the ionized absorber model zxipab along with a cooling ow model and a reflection component, we model the broadband Chandra/HETG and NuSTAR spectra of two IPs: NY Lup and V1223 Sgr. We nd that this model describes well many of the H and He like emission lines from medium Z elements, which arises from the collisionally excited plasma. However the model fails to account for some of the He like triplets from medium Z elements, which points towards its photo-ionization origin. We do not find a compelling evidence for a blackbody component to model the soft excess seen in the residuals of the Chandra/HETG spectra, which could be due to the uncertainties in estimation of the interstellar absorption of these sources using Chandra/HETG data and/or excess fluxes seen in some photo-ionized emission lines which are not accounted by the cooling ow model. We describe the implications of this model with respect to the geometry of the pre-shock region in these two IPs
Document ID
20210018671
Acquisition Source
Goddard Space Flight Center
Document Type
Accepted Manuscript (Version with final changes)
Authors
Nazma Islam Syeda
(Harvard-Smithsonian Center for Astrophysics Cambridge, Massachusetts, United States)
Koji Mukai
(University of Maryland, Baltimore County Baltimore, Maryland, United States)
Date Acquired
July 14, 2021
Publication Date
September 29, 2021
Publication Information
Publication: Astrophysical Journal
Publisher: AAS
Volume: 919
Issue: 2
Issue Publication Date: October 1, 2021
ISSN: 0004-637X
e-ISSN: 1538-4357
Subject Category
Numerical Analysis
Funding Number(s)
CONTRACT_GRANT: 80GSFC21M0002
CONTRACT_GRANT: 80GSFC21M0002
Distribution Limits
Public
Copyright
Public Use Permitted.
Technical Review
External Peer Committee
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