Related papers: Microlensing towards the Small Magellanic Cloud. E…
The first micro-lensing event discovered towards the Small Magellanic Cloud by the MACHO collaboration (Alcock et al. 1997b) had a very long time scale, t_0 = 123 days. The EROS collaboration (Palanque-Delabrouille et al. 1997) discovered a…
The recent observations of microlensing events in the LMC by the MACHO and EROS collaborations suggest that an important fraction of the galactic halo is in the form of Massive Halo Objects (MHO) of about 0.1 M_{\odot}. Here, we argue that…
It has been proposed that the MACHOs in our galaxy could be clumped in globular cluster--like associations or RAMBOs (robust associations of massive baryonic objects) (Moore \& Silk 1995). Here we investigate the effect such clustering has…
Recent observations of lensed galaxies at cosmological distances have detected individual stars that are extremely magnified when crossing the caustics of lensing clusters. In idealized cluster lenses with smooth mass distributions, two…
There is abundant evidence that the mass of the Universe is dominated by dark matter of unknown form. The MACHO project is one of several teams searching for the dark matter around our Galaxy in the form of Massive Compact Halo Objects…
We apply the pixel method of analysis (sometimes called ``pixel lensing'') to a small subset of the EROS-1 microlensing observations of the bar of the Large Magellanic Cloud (LMC). The pixel method is designed to find microlensing events of…
We present photometry and analysis of the microlensing alert MACHO 96-LMC-2. The ~3% photometry provided by the Global Microlensing Alert Network follow--up effort reveals a periodic modulation in the lightcurve. We attribute this to…
We study the prospects for the current microlensing searches, which have recently discovered several candidates, to yield useful information about the flattening of the Galaxy dark matter halo. Models of HI warps and N-body simulations of…
We provide a status report on our search for dark matter in our Galaxy in the form of massive compact halo objects (MACHOs), using gravitational microlensing of background stars. This search uses a very large CCD camera on the dedicated…
We calculate the optical depth and the number of events due to gravitational microlensing towards the Galactic bulge, the spiral arm directions $\gamma$ Scutum, $\beta$ Scutum, $\gamma$ Normae, $\vartheta$ Muscae and some dwarf galaxies in…
We introduce a novel theoretical model to explain the long-standing puzzle of the nature of the microlensing events reported towards the Large Magellanic Cloud (LMC) by the MACHO and OGLE collaborations. We propose that a population of…
In a recent series of three papers, Belokurov, Evans, and Le Du, and Evans and Belokurov, reanalysed the MACHO collaboration data and gave alternative sets of microlensing events and an alternative optical depth to microlensing toward the…
We report on the first results from a large-scale observing campaign aiming to use astrometric microlensing to detect and place limits on the mass of single objects, including stellar remnants. We used the Hubble Space Telescope to monitor…
We present the analysis of the first two years of the OGLE search for gravitational lenses towards the Galactic bulge. We detected 9 microlensing events in an algorithmic search of $ \sim 10^8 $ measurements of $ \sim 10^6 $ stars. The…
We combine Spitzer and ground-based observations to measure the microlens parallax of OGLE-2005-SMC-001, the first such space-based determination since S. Refsdal proposed the idea in 1966. The parallax measurement yields a projected…
The existence of strong lensing systems with Einstein radii (Re) covering the full mass spectrum, from ~1-2" (produced by galaxy scale dark matter haloes) to >10" (produced by galaxy cluster scale haloes) have long been predicted. Many…
We present photometric observations of the MACHO-SMC-1 microlensing candidate collected by the OGLE-2 project. We show light curves of both components of the 1.6 arcsec blend: microlensed star and its optical companion. We find the…
(Abridged) Some 240 blue stars in the Small Magellanic Cloud are investigated on their fantastic irregular continuum variability. We report here two results regarding these stars. First, their optical flux excess is correlated to their…
We present a differential study of 500 Magellanic Cepheids with 3 million measurements obtained as a by-product of the EROS microlensing survey. The data-set is unbiased and provides an excellent basis for a differential analysis between…
We present the analysis of the light curves of 9 high-magnification single-lens gravitational microlensing events with lenses passing over source stars, including OGLE-2004-BLG-254, MOA-2007-BLG-176, MOA-2007-BLG-233/OGLE-2007-BLG-302,…