We present high-angular-resolution optical I-band imaging of 451 late K to mid-M nearby stars. These observations have been performed with Astralux and FastCam using the lucky imaging technique. We found 70 companions with separations between 0.1 and 3.5 arcsec, out of which 28 are new discoveries. We derive a total binary fraction of 20.3+ 6.9- 5

We report our multiwavelength study of the 2011 outburst evolution of the newly discovered black hole candidate X-ray binary Swift J1357.2-0933. We analysed the Swift X-ray Telescope and Ultraviolet/Optical Telescope (UVOT) data taken during the ˜7 months duration of the outburst. It displayed a 2-10 keV X-ray peak luminosity of ˜1035(D/1.5 kpc)2

Multiple systems have long been used to probe the origin and evolution of stars of all masses. Only in the past 10-15 years have such studies been extended to brown dwarfs and the lowest mass stars through binary surveys of both young star forming regions and the older field population. In addition, a groundswell of interest in M dwarfs in recent

Light curves for sixty WASP-12 b's transits observed in 2010-2012 are given. Data were collected with 0.5-2.6-m telescopes located in thirteen observatories distributed around the world. Details on observations, data reduction, and analysis are given in the source paper. (1 data file).

We measure the differential microlensing of the broad emission lines between 18 quasar image pairs in 16 gravitational lenses. We find that the broad emission lines are in general weakly microlensed. The results show, at a modest level of confidence (1.8σ), that high ionization lines such as C IV are more strongly microlensed than low ionization

In X-ray binaries, compact jets are known to commonly radiate at radio to infrared frequencies, whereas at optical to γ-ray energies, the contribution of the jet is debated. The total luminosity, and hence power of the jet, is critically dependent on the position of the break in its spectrum, between optically thick (self-absorbed) and optically