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Searches for extrasolar planets have uncovered an astonishing diversity of planetary systems, yet the frequency of solar system analogs remains unknown. The gravitational microlensing planet search method is potentially sensitive to multiple-planet systems containing analogs of all the solar system planets except Mercury. We report the detection of a(More)
In the favoured core-accretion model of formation of planetary systems, solid planetesimals accumulate to build up planetary cores, which then accrete nebular gas if they are sufficiently massive. Around M-dwarf stars (the most common stars in our Galaxy), this model favours the formation of Earth-mass (M(o)) to Neptune-mass planets with orbital radii of 1(More)
In this paper the optical data of the ESO Deep-Public-Survey observed with the Wide Field Imager and reduced with the THELI pipeline (Erben et al. 2005) are presented. These images are publicly released to the community. Our main scientific goals with this survey are to study the high-redshift universe by optically pre-selecting high-redshift objects from(More)
We present the discovery of a Neptune-mass planet OGLE-2007-BLG-368Lb with a planet–star mass ratio of q = [9.5 ± 2.1] × 10 −5 via gravitational microlensing. The planetary deviation was detected in real-time thanks to the high cadence of the Microlensing Observations in Astrophysics survey, real-time light-curve monitoring and intensive follow-up(More)
Observations of the gravitational microlensing event MOA 2003-BLG-32/OGLE 2003-BLG-219 are presented, for which the peak magnification was over 500, the highest yet reported. Continuous observations around the peak enabled a sensitive search for planets orbiting the lens star. No planets were detected. Planets 1.3 times heavier than Earth were excluded from(More)
We present proper motion (µ) catalog of 5,078,188 stars in 49 Optical Gravitational Lensing Experiment II (OGLE-II) Galactic bulge fields, with the total area close to 11 square degrees. The proper motion measurements are based on 138 − 555 I-band images taken during four observing seasons: 1997-2000. The catalogue stars are in the magnitude range 11 < I <(More)
Most known extrasolar planets (exoplanets) have been discovered using the radial velocity or transit methods. Both are biased towards planets that are relatively close to their parent stars, and studies find that around 17-30% (refs 4, 5) of solar-like stars host a planet. Gravitational microlensing, on the other hand, probes planets that are further away(More)
We analyze OGLE-2003-BLG-262, a relatively short (t E ¼ 12:5 AE 0:1 day) microlensing event generated by a point-mass lens transiting the face of a K giant source in the Galactic bulge. We use the resulting finite-source effects to measure the angular Einstein radius, E ¼ 195 AE 17 as, and so constrain the lens mass to the FWHM interval 0:08 < M =M < 0:54.(More)
In the era of precision cosmology, it is essential to determine the Hubble constant to an accuracy of three per cent or better. At present, its uncertainty is dominated by the uncertainty in the distance to the Large Magellanic Cloud (LMC), which, being our second-closest galaxy, serves as the best anchor point for the cosmic distance scale. Observations of(More)
We describe the discovery of the longest microlensing event ever observed, OGLE-1999-BUL-32, also independently identified by the MACHO collaboration as MACHO-99-BLG-22. This unique event has an Einstein radius crossing time of 641 days. The high quality data obtained with difference image analysis shows a small but significant parallax signature. This(More)