Chandra 4–8 keV image of the central part of M 82. Left: all 13 exposures are used to construct the image. The image is centred at RA = 09^h55^m51.6^s, Dec = +69° 40′46″. The image size is 60″ × 40″. The scale bar indicates 10 arcsec (projected distance of ≈170 pc at M 82). Regarding the image orientation, north is up and east is to the left. Data are integrated counts displayed in logarithmic intervals. Right: same image as in the left panel, but in nine discrete colour intervals (aips0) overlaid with an ellipse enclosing the bright part of the diffuse emission and the spectral aperture for 21 discrete sources detected within the ellipse. The source numbers from 0 to 20 assigned to individual sources are labelled. Positions of the 32 radio SNR candidates selected by Fenech et al. (2010) and of SN2008iz are marked by cross symbols in yellow and magenta, respectively.