Publications (30)
Acceleration and Parallax Effects in Gravitational Microlensing
M. C. Smith, S. Mao, B. Paczynski
To generate the standard microlensing light curve one assumes that the relative motion of the source, the lens, and the observer is linear. In reality, the relative motion is likel…
Cluster AgeS Experiment: The Age and Distance of the Globular Cluster omega Centauri Determined from Observations of the Eclipsing Binary OGLEGC17
I. B. Thompson, J. Kaluzny, W. Pych +5
We use masses, radii, and luminosities of the detached eclipsing binary OGLEGC17 derived from photometric and spectroscopic observations to calculate the age and distance of the gl…
Microlens OGLE-2005-BLG-169 Implies Cool Neptune-Like Planets are Common
A. Gould, A. Udalski, D. An +33
We detect a Neptune mass-ratio (q~8e-5) planetary companion to the lens star in the extremely high-magnification (A~800) microlensing event OGLE-2005-BLG-169. If the parent is a ma…
Coronal activity from the ASAS eclipsing binaries
D. M. Szczygiel, A. Socrates, B. Paczynski +2
We combine the catalogue of eclipsing binaries from the All Sky Automated Survey (ASAS) with the ROSAT All Sky Survey (RASS). The combination results in 836 eclipsing binaries that…
e-VLBI observations of SN2001em - an off-axis GRB candidate
Z. Paragi, M. A. Garrett, B. Paczynski +5
Studying transient phenomena with the Very Long Baseline Interferometry (VLBI) technique faces severe difficulties because the turnaround time of the experiments from the observati…
The Optical Gravitational Lensing Experiment. Search for Planetary and Low-Luminosity Object Transits in the Galactic Disk. Results of 2001 Campaign
A. Udalski, B. Paczynski, K. Zebrun +6
We present results of an extensive photometric search for planetary and low-luminosity object transits in the Galactic disk stars commencing the third phase of the Optical Gravitat…
OGLE 2003-BLG-235/MOA 2003-BLG-53: A planetary microlensing event
I. A. Bond, A. Udalski, M. Jaroszynski +29
We present observations of the unusual microlensing event OGLE 2003-BLG-235/MOA 2003-BLG-53. In this event a short duration (~7 days) low amplitude deviation in the light curve due…
The Optical Depth to Gravitational Microlensing in the Direction of the Galactic Bulge
A. Udalski, M. Szymanski, K. Z. Stanek +6
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…
Microlensing optical depth toward the Galactic Bulge using bright sources from OGLE-II
T. Sumi, P. R. Wozniak, A. Udalski +8
We present a measurement of the microlensing optical depth toward the Galactic Bulge based on 4 years of the OGLE-II survey using Red Clump Giant (RCG). Using 32 events we find tau…
Eclipsing binaries in ASAS catalog
B. Paczynski, D. Szczygiel, B. Pilecki +1
ASAS is a long term project to monitor bright variable stars over the whole sky. It has discovered 50,122 variables brighter than V < 14 mag south of declination +28 degrees, and a…
Discovery of a Jupiter/Saturn Analog with Gravitational Microlensing
B. S. Gaudi, D. P. Bennett, A. Udalski +66
Searches for extrasolar planets have uncovered an astonishing diversity of planetary systems, yet the frequency of solar system analogs remains unknown. The gravitational microlens…
Results from the Optical Gravitational Lensing Experiment (OGLE)
B. Paczynski, K. Z. Stanek, A. Udalski +6
The analysis of the first three years of the OGLE data revealed 12 microlensing events of the Galactic bulge stars, with the characteristic time scales in the range $ 8.6 < t_0 < 8…
OGLE small amplitude red giant variables in the Galactic Bar
J. J. Wray, L. Eyer, B. Paczynski
Among over 200,000 Galactic Bulge variable stars in the public domain OGLE catalogue, we found over 15,000 red giant variables following two well defined period -- amplitude relati…
Discovery of a Cool Planet of 5.5 Earth Masses Through Gravitational Microlensing
J. -P. Beaulieu, D. P. Bennett, P. Fouque +46
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 suffi…
A mildly relativistic radio jet from the otherwise normal Type Ic Supernova 2007gr
Z. Paragi, G. B. Taylor, C. Kouveliotou +11
The class of type Ic supernovae have drawn increasing attention since 1998 owing to their sparse association (only four so far) with long duration gamma-ray bursts. Although both p…
DIFFRACTION EFFECTS IN MICROLENSING OF Q2237+0305
M. Jaroszynski, B. Paczynski
Geometrical optics provides an excellent description for quasar images crossing caustics which are formed by gravitational microlensing of objects like Q2237+0305. Within this appr…
The Microlensing Planet Finder: Completing the Census of Extrasolar Planets in the Milky Way
D. P. Bennett, I. Bond, E. Cheng +21
The Microlensing Planet Finder (MPF) is a proposed Discovery mission that will complete the first census of extrasolar planets with sensitivity to planets like those in our own sol…
Gamma-Ray Bursts from quark stars
B. Paczynski, P. Haensel
Long gamma-ray bursts (GRBs) are believed to be related to the explosion of type Ic supernovae, which have been stripped of their hydrogen and helium envelopes. There appear to be…
The Optical Gravitational Lensing Experiment. the Early Warning System
A. Udalski, M. Szymanski, J. Kaluzny +4
The discoveries of 17 microlensing event candidates have been reported over the last year by three teams conducting unprecedented mass photometric searches in the direction of the…
First Space-Based Microlens Parallax Measurement: Spitzer Observations of OGLE-2005-SMC-001
Subo Dong, A. Udalski, A. Gould +20
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…
The Masses of Nearby Dwarfs can be Determined with Gravitational Microlensing
B. Paczynski
Microlensing of distant stars in the Milky Way by the nearby high proper motion stars offers a direct way to precisely measure the masses of single lower main sequence stars and br…
A Jovian-mass Planet in Microlensing Event OGLE-2005-BLG-071
A. Udalski, M. Jaroszynski, B. Paczynski +30
We report the discovery of a several-Jupiter mass planetary companion to the primary lens star in microlensing event OGLE-2005-BLG-071. Precise (<1%) photometry at the peak of the…
The Optical Gravitational Lensing Experiment. UBVI Photometry of Stars in Baade's Window
B. Paczynski, A. Udalski, M. Szymanski +5
We present UBVI photometry for 8530 stars in Baade's Window obtained during the OGLE-II microlensing survey. Among these are over one thousand red clump giants. 1391 of them have p…
The Color--Magnitude Diagram in Baade's Window Revisited
M. Kiraga, B. Paczynski, K. Z. Stanek
We have reanalyzed the OGLE and photometry of stars in Baade's Window, and we confirm the extinction map published by Stanek (1996). However, we find that th…
A Possible Planetary Event OGLE-2002-BLG-055
M. Jaroszynski, B. Paczynski
The microlensing event OGLE-2002-BLG-055 has a single, but very reliable data point, deviating upward from a single source microlensing light curve by 0.6 mag. The simplest interpr…
Ellipsoidal Variability in the OGLE Planetary Transit Candidates
E. Sirko, B. Paczynski
We analyze the photometry of 117 OGLE stars with periodic transit events for the presence of ellipsoidal light variations, which indicate the presence of massive companions. We fin…
The Cosmic Microwave Background Dipole as a Cosmological Effect
M. Jaroszynski, B. Paczynski
A conventional explanation of the dipole anisotropy of the cosmic microwave background (CMB) radiation is in terms of the Doppler effect: our galaxy is moving with respect to CMB f…
Are the Ogle Microlenses in the Galactic Bar?
B. Paczynski, K. Z. Stanek, A. Udalski +5
The analysis of the first two years of OGLE data revealed 9 microlensing events of the galactic bulge stars, with the characteristic time scales in the range day…
The Distribution of Galactic Disk Stars in Baade's Window
B. Paczynski, K. Z. Stanek, A. Udalski +4
The color-magnitude diagram of stars obtained for Baade's Window towards the Galactic bulge with the OGLE project reveals a surprisingly narrow main sequence…
A model of AW UMa
B. Paczynski, R. Sienkiewicz, D. M. Szczygiel
The contact binary AW UMa has an extreme mass ratio, with the more massive component (the current primary) close to the main sequence, while the low mass star at q ~ 0.1 (the curre…