We present XMM-Newton observations of NGC 891 , a nearby edge-on spiral galaxy .
We analyse the extent of the diffuse emission emitted from the disk of the galaxy , and find that it has a single temperature profile with best fitting temperature of 0.26 keV , though the fit of a dual-temperature plasma with temperatures of 0.08 and 0.30 keV is also an acceptable fit .
There is a considerable amount of diffuse X-ray emission protruding from the disk in the NW direction out to approximately 6 kpc .
We analyse the point source population using a Chandra observation , using a maximum likelihood method to find that the slope of the cumulative luminosity function of point sources in the galaxy is -0.77 ^ { +0.13 } _ { -0.1 } .
Using a sample of other local galaxies , we compare the X-ray and infrared properties of NGC 891 with those of ’ normal ’ and starburst spiral galaxies , and conclude that NGC 891 is most likely a starburst galaxy in a quiescent state .
We establish that the diffuse X-ray luminosity of spirals scales with the far infra-red luminosity as L _ { X } \propto L _ { FIR } ^ { 0.87 \pm 0.07 } , except for extreme starbursts , and NGC 891 does not fall in the latter category .
We study the supernova SN1986J in both XMM-Newton and Chandra observations , and find that the X-ray luminosity has been declining with time more steeply than expected ( L _ { X } \propto t ^ { -3 } ) .