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We present the rest-frame optical and infrared colours of a complete sample of 1114 z 0.3 galaxies from the Spitzer Wide-Area Infrared Extragalactic (SWIRE) Legacy Survey and the Sloan Digital Sky Survey (SDSS). We discuss the optical and infrared colours of our sample and analyse in detail the contribution of dusty star-forming galaxies and

We report on near-infrared and optical observations of the GRB 970616 error box and of the X-ray sources discovered by ASCA and ROSAT in the region. No optical transient was found either within the IPN band or in the X-ray error boxes, similarly to other bursts, and we suggest that either considerable intrinsic absorption was present (like GRB

As part of a monitoring campaign of quiescent and outbursting low-mass X-ray binaries with the CTIO/SMARTS telescopes and the Faulkes telescopes , we report observations of Aql X-1 and confirm the optical counterpart of the new X-ray outburst (ATel #1216). On 2007 Aug 30 (MJD 54342.26) we performed optical observations of Aql X-1 for 100 sec each

After a decade of intense studies using the latest X-ray and optical telescopes, the nature of ultraluminous X-ray sources (ULXs) is still largely unknown. No definitive answer has emerged on the question of the mass of the black hole powering these objects (intermediate-mass or supercritical stellar-mass?). Further, we lack even basic knowledge