The nature of the nuclear and extended emission in NGC 5643

We propose a 50 ks XMMNewton observation of the Seyfert 2 galaxy, NGC 5643,with the aim of answering two questions left unanswered by the previous, muchshorter (less than 10 ks) XMMNewton observation. In particular, we want to: a)Measure the O vii triplet with sufficient signaltonoise to unambiguouslydistinguish between photoionized and collisionally ionized matter. Contrary tomost other Seyferts, in this source collisional plasma seems to dominate, butthe previous measures are inconclusive. b) Distinguish between the twoalternative models for the hard Xray emission, i.e. nuclear emission plusscattering component or partially absorbed Compton reflect ion. This will helpus to better understand the nature and morphology of the obscuring matter. truncated!, Please see actual data for full text [truncated!, Please see actual data for full text]