Abstract. The XMM-OM instrument extends the spectral coverage of the XMM-Newton observatory into the ultraviolet and optical range. It provides imaging and time-resolved data on targets simultaneously with observations in the EPIC and RGS. It also has the ability to track stars in its field of view, thus providing an improved post-facto aspect solution for the spacecraft. An overview of the XMM-OM and its operation is given, together with current information on the performance of the instrument.

Abstract. The initial results from XMM-Newton observations of the rich cluster of galaxies Abell 1795 are presented. The spatially-resolved X-ray spectra taken by the European Photon Imaging Cameras (EPIC) show a temperature drop at a radius of ∼200 kpc from the cluster center, indicating that the ICM is cooling. Both the EPIC and the Reflection Grating Spectrometers (RGS) spectra extracted from the cluster center can be described by an isothermal model with a temperature of ∼4 keV. The volume emission measure of any cool component (< 1 keV) is less than a few % of the hot component at the cluster center. A strong O viii Lyman α line was detected with the RGS from the cluster core. The O abundance and its ratio to Fe at the cluster center is 0.2-0.5 and 0.5-1.5 times the solar value, respectively.

We present an analysis of the submillimetre/X‐ray properties of 19 X‐ray absorbed, Compton‐thin quasi‐stellar objects (QSOs) selected to have luminosities and redshifts that represent the peak of cosmic QSO activity, i.e. ∼ L* objects at 1 < z < 3. Of these, we present new data for 11 objects not previously observed at submillimetre wavelengths and additional data for a further three. The detection rate is 42 per cent, much higher than typically reported for samples of QSOs. Detection statistics show (at the 3–4σ level) that this sample of absorbed QSOs has a higher submillimetre output than a matched sample of unabsorbed QSOs. We argue that the far‐infrared luminosity is produced by massive star formation. In this case, the correlation found between far‐infrared luminosity and redshift can be interpreted as cosmological evolution of the star formation rate in the QSO host galaxies. Because the submillimetre luminous phase is confined to z > 1.5, the high star formation rates are consistent with a scenario in which the QSOs evolve to become local luminous elliptical galaxies. Combining these results with previously published data for X‐ray unabsorbed QSOs and submillimetre‐selected galaxies, we propose the following evolutionary sequence: the forming galaxy is initially far‐infrared luminous but X‐ray weak similar to the sources discovered by the Submillimetre Common‐User Bolometer Array (SCUBA); as the black hole and spheroid grow with time, a point is reached when the central QSO becomes powerful enough to terminate the star formation and eject the bulk of the fuel supply (the Compton‐thin absorbed QSO phase); this transition is followed by a period of unobscured QSO activity, which subsequently declines to leave a quiescent spheroidal galaxy.

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The correlation, found in nearby galaxies, between black hole mass and stellar bulge mass implies that the formation of these two components must be related. Here we report submillimeter photometry of eight x-ray absorbed active galactic nuclei which have luminosities and redshifts characteristic of the sources that produce the bulk of the accretion luminosity in the universe. The four sources with the highest redshifts are detected at 850 microns, with flux densities between 5.9 and 10.1 milliJanskies, and hence are ultraluminous infrared galaxies. Interpreting the submillimeter flux as emission from dust heated by starbursts, these results suggest that the majority of stars in spheroids were formed at the same time as their central black holes built up most of their mass by accretion, accounting for the observed demography of massive black holes in the local universe. The skewed rate of submillimeter detection with redshift is consistent with a high redshift epoch of star formation in radio quiet active galactic nuclei, similar to that seen in radio galaxies.In the local universe, central black holes are found in most galaxy spheroids (a collective term for elliptical galaxies and the bulges of spiral galaxies) with mass roughly proportional to that of the spheroid (0.13% ±0.4 dex) (1). The simplest explanation for this proportionality is that the black hole mass is built up in active galactic nuclei (AGN) by accretion of the same gas that is rapidly forming the stars which make up the spheroid, i.e. the formation of the spheroid and the growth of the massive black hole are coeval. Assuming that 10% of the spheroid mass M is converted from hydrogen to helium in stars (2) at an efficiency of 0.007 and radiated, and that 0.13% of the spheroid mass M is accreted by the central black hole (1) at 10% efficiency, the ratio of radiation emitted by the starburst (E SB ) to that emitted by the AGN (E AGN )is: