Morphology

The X-ray jet extends 1.'9 (110 kpc) westward from the nucleus in p.a. 281$^{\circ }$ (Fig. 2). This direction is only 1$^{\circ }$ away from that quoted for the radio jet out to 3$^{\prime }$ (170 kpc) from the nucleus (PRM). Such a difference in p.a. is within the errors of measurement, so we can conclude that the X-ray and radio jets are coincident.

The profile of X-ray emission along the jet, shown in Fig. 6, consists of a number of `knots', the brightest of which is $30\arcsec$ from the nucleus. In Section 4.1, we shall argue that the western radio lobe is the nearer. The ratio of the X-ray fluxes of the western and eastern jets, using the brightest part of the western jet, is more than a factor of 10 (Fig. 6), suggesting relativistic boosting, as discussed in Section 4.3.2.

We have compared the transverse profiles across the jet with the expected psf. After deconvolution from the psf, the jet is found to be transversely extended. The width of the jet varies somewhat along its length, but its typical FWHM = 2.''0 (1.9 kpc). We are confident of this transverse extent because: a) the profile of the compact source 152 $^{\prime\prime}$ from the nucleus in p.a. 40$^{\circ }$ agrees well with the expected psf at its location (Section 3.2.1), and b) the linear feature that results from the CCD readout of the strong nuclear source gives a measure of the 1d psf at the nucleus; this feature is much narrower than the jet. These arguments show that the measured jet width is not a result of poor aspect solution or focus.

The jet is so faint in the radio that it is difficult to measure its width. PRM state ``no accurate estimate of the jet's width is possible, but it is clearly not greatly resolved by the 7.''5 beam''. Thus the upper limit to the radio width is consistent with the X-ray width.