Skip to main content

Research Repository

Advanced Search

An XMM-Newton view of M101 - III. Diffuse X-ray emission

Warwick, RS; Jenkins, LP; Read, AM; Roberts, TP; Owen, RA

An XMM-Newton view of M101 - III. Diffuse X-ray emission Thumbnail


RS Warwick

LP Jenkins

AM Read

RA Owen


We present a study of the X-ray properties of the nearby face-on Scd spiral galaxy M101 based on recent XMM–Newton observations. In this third and final paper in the present series, we focus on the spatial and spectral properties of the residual emission, after excluding bright X-ray sources with LX > 1037 erg s−1. Within a central region of radius 10 arcmin (21 kpc), the X-ray emission broadly traces the pattern of the spiral arms, establishing a strong link with recent star formation, but it also exhibits a radial scalelength of ≈2.6 arcmin (5.4 kpc) consistent with optical data. We estimate the soft X-ray luminosity within the central 5 arcmin (10.5 kpc) region to be LX ≈ 2.1 × 1039 erg s−1 (0.5–2 keV), the bulk of which appears to originate as diffuse emission. We find a two-temperature thermal model best fits the spectral data with derived temperatures of keV which are very typical of the diffuse components seen in other normal and starburst galaxies. More detailed investigation of the X-ray morphology reveals a strong correlation with images recorded in the far-ultraviolet through to V band, with the best match being with the U band. We interpret these results in terms of a clumpy thin-disc component which traces the spiral arms of M101 plus an extended lower halo component with large filling factor.


Warwick, R., Jenkins, L., Read, A., Roberts, T., & Owen, R. (2007). An XMM-Newton view of M101 - III. Diffuse X-ray emission. Monthly Notices of the Royal Astronomical Society, 376(4), 1611-1620.

Journal Article Type Article
Publication Date Apr 21, 2007
Deposit Date Feb 20, 2014
Publicly Available Date Feb 21, 2014
Journal Monthly Notices of the Royal Astronomical Society
Print ISSN 0035-8711
Electronic ISSN 1365-2966
Publisher Royal Astronomical Society
Peer Reviewed Peer Reviewed
Volume 376
Issue 4
Pages 1611-1620
Keywords Galaxies : individual : M101, Galaxies : spiral, X-rays : galaxies, X-rays : ISM, Nearby spiral galaxies, Rosat PSPC Observations, Chandra observations, Interstellar-medium, Evolution-explorer, Source population, H-Alpha, Hot gas, Superwinds, Remnants.


Published Journal Article (1.2 Mb)

Copyright Statement
This article has been published in the Monthly Notices of the Royal Astronomical Society © 2007 The Authors. Journal compilation © 2007 RAS. Published by Oxford University Press on behalf of The Royal Astronomical Society. All rights reserved.

You might also like

Downloadable Citations