Related papers: A microlensing search for cold molecular clouds in…
We present a weak lensing analysis of the Coma Cluster using the Sloan Digital Sky Survey (SDSS) Data Release Five. Complete imaging of a ~ 200 square degree region is used to measure the tangential shear of this cluster. The shear is fit…
Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary…
We report the automatic detection of a new sample of very low surface brightness (LSB) galaxies, likely members of the Virgo cluster. We introduce our new software, {\tt DeepScan}, that has been designed specifically to detect extended LSB…
The widely varying dwarf galaxy counts in different environments provide a strong challenge to standard hierarchical clustering models. The luminosity function is not universal, but seems to be strongly dependent upon environment. In this…
Recent astronomical data strongly suggest that a significant part of the dark matter, composing the Local Group and Virgo Supercluster, is not incorporated into the galaxy haloes and forms diffuse components of these galaxy clusters.…
We study gravitational wave microlensing by primordial black holes (PBHs), accounting for the effect of a particle dark matter minihalo surrounding them. Such minihaloes are expected when PBHs make up only a fraction of all dark matter. We…
We propose a novel method to select satellite galaxies in outer regions of galaxy groups or clusters using weak gravitational lensing. The method is based on the theoretical expectation that the tangential shear pattern around satellite…
The Arecibo Legacy Fast ALFA survey is in the process of yielding a complete HI dataset of the Virgo Cluster and its environs (Giovanelli et al. 2007, Kent et al., in preparation). Assuming a distance to Virgo of 16.7 Mpc, the minimum…
We have mapped the Auriga/California molecular cloud with the Herschel PACS and SPIRE cameras and the Bolocam 1.1 mm camera on the Caltech Submillimeter Observatory (CSO) with the eventual goal of quantifying the star formation and cloud…
Major progresses have been made this last year towards a better knowledge of the invisible mass. Michel Spiro will talk in details about the micro-lensing experiments and their promising results; the ROSAT satellite has provided extended…
The idea that dark matter in the form of small compact bodies (most plausibly planetary mass primordial black holes) betrays its presence by the microlensing of quasars, has been stimulated by statistical studies of quasar light curves and…
We have acquired deep, H-band, imaging for a sample of 286 Virgo cluster galaxies with B <= 16 mag and extracted surface photometry from optical g,r,i,z Sloan Digital Sky Survey images of 742 Virgo Cluster Catalog galaxies, including those…
We measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data…
We have carried out a fully sampled large area ($4^{\circ} \times 8^{\circ}$) 21cm \HI line survey of part of the Virgo cluster using the Jodrell Bank multi-beam instrument. The survey has a sensitivity some 3 times better than the standard…
We present the Halpha imaging observations of 273 late-type galaxies in the nearby rich galaxy clusters Virgo, A1367, Coma, Cancer, Hercules and in the Great Wall, carried out primarily with the 2.1m telescope of the San Pedro Martir…
By monitoring $10^6$ quasars one could search for lensing by stars and Massive Compact Halo Objects (Machos) out to redshifts $z\sim 4$. If Machos have a present cosmological density $\Omega_{L,0}=1\%$, then the expected event rate is…
Weak lensing is an important technique to determine the masses of galaxy groups. However, the distortion imprint on the shape of the background galaxies is affected by all the mass content along the line-of-sight. Using COSMOS shear mock…
We present an update of results from the search for microlensing towards the Large Magellanic Cloud (LMC) by EROS (Experience de Recherche d'Objets Sombres). We have now monitored 25 million stars over three years. Because of the small…
In this Letter we present calibrated observations of the average mass of galaxies with 22< I < 25 in the Hubble Deep Field. We measure the mean mass profile using the statistical gravitational lens distortion of faint blue background…
Intrinsic variations of the projected density profiles of clusters of galaxies at fixed mass are a source of uncertainty for cluster weak lensing. We present a semi-analytical model to account for this effect, based on a combination of…