Bennett, D. P., Rhie, S. H., Nikolaev, S., Gaudi, B. S., Udalski, A., Gould, A., ...
We present a new analysis of the Jupiter+Saturn analog system, OGLE-2006-BLG-109Lb,c, which was the first double planet system discovered with the gravitational microlensing method. This is the only...
Rest, A., Foley, R. J., Gezari, S., Narayan, G., Draine, B., Olsen, K., ...
We report the discovery of a supernova (SN) with the highest apparent energy output to date and conclude that it represents an extreme example of the Type IIn subclass. The SN, which was discovered...
Pietrukowicz, P., Minniti, D., Diaz, R. F., Fernandez, J. M., Zoccali, M., Gieren, W., ...
We used VLT/VIMOS images in the V band to obtain light curves of extrasolar planetary transits OGLE-TR-111 and OGLE-TR-113, and candidate planetary transits: OGLE-TR-82, OGLE-TR-86, OGLE-TR-91,...
Soszynski, I., Udalski, A., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Wyrzykowski, L., ...
The fourth part of the OGLE-III Catalog of Variable Stars presents 91 995 long-period variables (LPVs) in the Large Magellanic Cloud (LMC). This sample consists of 79 200 OGLE Small Amplitude Red...
Kozlowski, Szymon, Kochanek, Christopher S., Udalski, A., Wyrzykowski, L., Soszynski, I., Szymanski, M. K., ...
Robust fast methods to classify variable light curves in large sky surveys are becoming increasingly important. While it is relatively straightforward to identify common periodic stars and particular...
Elemental abundances in the Galactic bulge from microlensed dwarf stars (2009)
Bensby, T., Feltzing, S., Johnson, J. A., Gould, A., Sana, H., Gal-Yam, A., ...
We present elemental abundances of 13 microlensed dwarf and subgiant stars in the Galactic bulge, which constitute the largest sample to date. We show that these stars span the full range of...
Yee, J. C., Udalski, A., Sumi, T., Dong, Subo, Kozłowski, S., Bird, J. C., ...
We analyze the extreme high-magnification microlensing event OGLE-2008-BLG-279, which peaked at a maximum magnification of A ~ 1600 on 30 May 2008. The peak of this event exhibits both finite-source...
Batista, V., Dong, Subo, Gould, A., Beaulieu, J. P., Cassan, A., Christie, G. W., ...
We analyze OGLE-2007-BLG-050, a high magnification microlensing event (A ~ 432) whose peak occurred on 2 May, 2007, with pronounced finite-source and parallax effects. We compute planet detection...
OGLE-2009-BLG-076S - The most metal-poor dwarf star in the Galactic bulge (2009)
Bensby, T., Feltzing, S., Johnson, J. A., Gal-Yam, A., Udalski, A., Gould, A., ...
Measurements based on a large number of red giant stars suggest a broad metallicity distribution function (MDF) for the Galactic bulge, centered on [Fe/H]=-0.1. However, recently, a new opportunity...
Chemical evolution of the Galactic bulge as traced by microlensed dwarf and subgiant stars (2009)
Bensby, T., Johnson, J. A., Cohen, J., Feltzing, S., Udalski, A., Gould, A., ...
Aims. Our aims are twofold. First we aim to evaluate the robustness and accuracy of stellar parameters and detailed elemental abundances that can be derived from high-resolution spectroscopic...
Wyrzykowski, L., Kozlowski, S., Skowron, J., Belokurov, V., Smith, M. C., Udalski, A., ...
We present the results from the OGLE-II survey (1996-2000) towards the Large Magellanic Cloud (LMC), which has the aim of detecting the microlensing phenomena caused by dark matter compact objects in...
A systematic fitting scheme for caustic-crossing microlensing events (2009)
Kains, N., Cassan, A., Horne, K., Albrow, M. D., Dieters, S., Fouqué, P., ...
We outline a method for fitting binary-lens caustic-crossing microlensing events based on the alternative model parametrization proposed and detailed by Cassan. As an illustration of our methodology,...
Gould, A., Udalski, A., Monard, B., Horne, K., Dong, Subo, Miyake, N., ...
Parallax is the most fundamental technique to measure distances to astronomical objects. Although terrestrial parallax was pioneered over 2000 years ago by Hipparchus (ca. 140 BCE) to measure the...
Bensby, T., Johnson, J. A., Cohen, J., Feltzing, S., Udalski, A., Gould, A., ...
AIMS. Our aims are twofold. First we aim to evaluate the robustness and accuracy of stellar parameters and detailed elemental abundances that can be derived from high-resolution spectroscopic...
Soszynski, I., Udalski, A., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Wyrzykowski, L., ...
The third part of the OGLE-III Catalog of Variable Stars comprises 24906 RR Lyr stars in the Large Magellanic Cloud (LMC). This sample consists of 17693 fundamental-mode (RRab), 4958 first-overtone...
Pietrzynski, G., Thompson, I., Graczyk, D., Gieren, W., Udalski, A., Szewczyk, O., ...
We have analyzed the double-lined eclipsing binary system OGLE-051019.64-685812.3 in the LMC which consists of two G4 giant components with very similar effective temperatures. A detailed analysis of...
A Census of Exoplanets in Orbits Beyond 0.5 AU via Space-based Microlensing (2009)
Bennett, David P., Anderson, J., Bond, I., Cheng, E., Cook, K., ...
A space-based gravitational microlensing exoplanet survey will provide a statistical census of exoplanets with masses greater than 0.1 Earth-masses and orbital separations ranging from 0.5AU to...
Woollands, Robyn M., Cottrell, P. L., Udalski, A.
This paper presents the initial results of a multi-site photometric programme to examine the extraordinary behaviour displayed by 18 R Coronae Borealis (RCB) stars in the Magellanic Clouds (MCs). RCB...
Udalski, A., Soszynski, I., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Wyrzykowski, L., ...
We present OGLE-III Photometric Maps of the Small Magellanic Cloud. They contain precise, calibrated VI photometry of about 6.2 million stars from 41 OGLE-III fields in the SMC observed regularly in...
Miszalski, B., Acker, A., Moffat, A. F. J., Parker, Q. A., Udalski, A.
Binarity has been hypothesised to play an important, if not ubiquitous, role in the formation of planetary nebulae (PNe). Yet there remains a severe paucity of known binary central stars required to...
Coe, M. J., Schurch, M., McBride, V. A., Corbet, R. H. D., Townsend, L. J., Udalski, A., ...
Optical and X-ray observations are presented here of a newly reported X-ray transient system in the Small Magellanic Cloud - SXP7.92. A detailed analysis of the X-ray data reveal a coherent period of...
A systematic fitting scheme for caustic-crossing microlensing events (2009)
Kains, N., Cassan, A., Horne, K., Albrow, M. D., Dieters, S., Fouque, P., ...
We outline a method for fitting binary-lens caustic-crossing microlensing events based on the alternative model parameterisation proposed and detailed in Cassan (2008). As an illustration of our...
OGLE-2005-BLG-071Lb, the Most Massive M Dwarf Planetary Companion? (2009)
Christie, G.W., Gaudi, B.S., Kubiak, M., Szymanski, M.K., Pietrzynski, G., Soszynski, I., ...
We combine all available information to constrain the nature of OGLE-2005-BLG-071Lb, the second planet discovered by microlensing and the first in a high-magnification event. These include...
OGLE-2005-BLG-071Lb, The Most Massive M Dwarf Planetary Companion? (2009)
Dong, S, Gould, A, Udalski, A, Anderson, J, Christie, GW, Gaudi, BS, ...
We combine all available information to constrain the nature of OGLE-2005-BLG-071Lb, the second planet discovered by microlensing and the first in a high-magnification event. These include...
A systematic fitting scheme for caustic-crossing microlensing events (2009)
Kains, N, Cassan, A, Horne, K, Albrow, MD, Dieters, S, Fouque, P, ...
We outline a method for fitting binary-lens caustic-crossing microlensing events based on the alternative model parametrization proposed and detailed by Cassan. As an illustration of our methodology,...
Yee, JC, Udalski, A, Sumi, T, Dong, S, Kozlowski, S, Bird, JC, ...
We analyze the extreme high-magnification microlensing event OGLE-2008-BLG-279, which peaked at a maximum magnification of A ~ 1600 on 2008 May 30. The peak of this event exhibits both finite-source...
Han, C, Hwang, KH, Kim, D, Udalski, A, Abe, F, Monard, LAB, ...
To improve the planet detection efficiency, current planetary microlensing experiments are focused on high magnificationevents searching for planetary signals near the peak of lensing light curves....
Soszynski, I., Udalski, A., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Wyrzykowski, L., ...
In the second part of the OGLE-III Catalog of Variable Stars (OIII-CVS) we present 197 type II Cepheids and 83 anomalous Cepheids in the Large Magellanic Cloud (LMC). The sample of type II Cepheids...
XROM and RCOM: Two New OGLE-III Real Time Data Analysis Systems (2008)
We describe two new OGLE-III real time data analysis systems: XROM and RCOM. The XROM system has been designed to provide continuous real time photometric monitoring of the optical counterparts of...
Schurch, M. P. E., Coe, M. J., Galache, J. L., Corbet, R. H. D., McGowan, K. E., McBride, V. A., ...
On 30th August 2006 SXP18.3 a high mass X-ray binary (HMXB) in the Small Magellanic Cloud (SMC) with an 18.3s pulse period was observed by Rossi X-ray Timing Explorer (RXTE). The source was seen...
Dong, Subo, Bond, I. A., Gould, A., Kozlowski, Szymon, Miyake, N., Gaudi, B. S., ...
We report the detection of the cool, Jovian-mass planet MOA-2007-BLG-400Lb. The planet was detected in a high-magnification microlensing event (with peak magnification A_max = 628) in which the...
Garcia-Varela, A., Pietrzynski, G., Gieren, W., Udalski, A., Soszynski, I., Walker, A., ...
We report on the discovery of a Cepheid population in the Sculptor Group spiral galaxy NGC 247 for the first time. On the basis of wide-field images collected in photometric surveys in V and I bands...
Soszynski, I., Poleski, R., Udalski, A., Szymanski, M. K., Kubiak, M., Pietrzynski, G., ...
We present the first part of a new catalog of variable stars (OIII-CVS) compiled from the data collected in the course of the third phase of the Optical Gravitational Lensing Experiment (OGLE-III)....
Miszalski, B., Acker, A., Moffat, A. F. J., Parker, Q. A., Udalski, A.
Progress in understanding the formation and evolution of planetary nebulae (PN) has been restricted by a paucity of well-determined central star masses. To address this deficiency we aim to (i)...
A transiting planet among 23 new near-threshold candidates from the OGLE survey - OGLE-TR-182 (2008)
Pont, F, Tamuz, O, Udalski, A, Mazeh, T, Bouchy, F, Melo, C, ...
By re-processing the data of the second season of the OGLE survey for planetary transits and adding new mesurements on the same fields gathered in subsequent years with the OGLE telescope, we have...
Towards A Census of Earth-mass Exo-planets with Gravitational Microlensing (2008)
Beaulieu, J. P., Kerins, E., Mao, S., Bennett, D., Cassan, A., Dieters, S., ...
Thirteen exo-planets have been discovered using the gravitational microlensing technique (out of which 7 have been published). These planets already demonstrate that super-Earths (with mass up to ~10...
Soszynski, I., Poleski, R., Udalski, A., Kubiak, M., Szymanski, M. K., Pietrzynski, G., ...
We report the discovery of three new triple-mode classical Cepheids in the Large Magellanic Cloud, two of them with the fundamental, first overtone and second overtone excited, and one pulsating...
The Optical Gravitational Lensing Experiment. Final Reductions of the OGLE-III Data (2008)
Udalski, A., Szymanski, M. K., Soszynski, I., Poleski, R.
We describe methods applied to the final photometric reductions and calibrations to the standard system of the images collected during the third phase of the Optical Gravitational Lensing Experiment...
Udalski, A., Soszynski, I., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Wyrzykowski, L., ...
We present the OGLE-III Photometric Maps of the Large Magellanic Cloud. They cover about 40 square degrees of the LMC and contain mean, calibrated VI photometry and astrometry of about 35 million...
Bennett, D. P., Bond, I. A., Udalski, A., Sumi, T., Abe, F., Fukui, A., ...
We report the detection of an extrasolar planet of mass ratio q ~ 2 x 10^(-4) in microlensing event MOA-2007-BLG-192. The best fit microlensing model shows both the microlensing parallax and finite...
Udalski, A, Pont, F, Naef, D, Melo, C, Bouchy, F, Santos, N C, ...
We present results of the photometric campaign for planetary and low-luminosity object transits conducted by the OGLE survey in the 2005 season (Campaign #5). About twenty of the most promising...
An optical & X-ray study of the counterpart to the SMC X-ray binary pulsar system SXP327 (2008)
Coe, M. J., Schurch, M., Galache, J., McBride, V. A., Townsend, L. J., ...
Optical and X-ray observations are presented here of a newly reported X-ray transient system in the Small Magellanic Cloud. The data reveal many previously unknown X-ray detections of this system and...
Binary Lenses in OGLE III EWS Database. Season 2005 (2008)
Skowron, J., Jaroszynski, M., Udalski, A., Kubiak, M., Szymanski, M. K., Pietrzynski, G., ...
We present nine new binary lens candidates from OGLE-III Early Warning System database for the season of 2005. We have also found four events interpreted as single mass lensing of double sources. The...
Discovery of a Jupiter/Saturn Analog with Gravitational Microlensing (2008)
Gaudi, B. S., Bennett, D. P., Udalski, A., Gould, A., Christie, G. W., Maoz, D., ...
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...
Clues to the Metallicity Distribution in the Galactic Bulge: Abundances in OGLE-2007_BLG-349S (2008)
Cohen, Judith G., Huang, Wenjin, Udalski, A., Gould, Andrew, Johnson, Jennifer
We present an abundance analysis based on high dispersion and high signal-to-noise ratio Keck spectra of a very highly microlensed Galactic bulge dwarf, OGLE-2007-BLG-349S, with Teff ~ 5400 K. The...
The distance to the Galactic Centre based on Population-II Cepheids and RR Lyrae stars (2008)
Groenewegen, M. A. T., Udalski, A., Bono, G.
Context: The distance to the Galactic Centre (GC) is of importance for the distance scale in the Universe. The value derived by Eisenhauer et al. (2005) of 7.62 +- 0.32 kpc based on the orbit of one...
Discovery of a Jupiter/Saturn Analog with Gravitational Microlensing (2008)
Gaudi, BS, Bennett, DP, Udalski, A, Gould, A, Christie, GW, Maoz, D, ...
Udalski, A., Pont, F., Naef, D., Melo, C., Bouchy, F., Santos, N. C., ...
We present results of the photometric campaign for planetary and low-luminosity object transits conducted by the OGLE survey in 2005 season (Campaign #5). About twenty most promising candidates...
McGowan, K. E., Coe, M. J., Schurch, M. P. E., Corbet, R. H. D., Galache, J. L., Udalski, A.
We present long-term optical and RXTE data of two X-ray binary pulsars in the Small Magellanic Cloud, SXP46.6 and SXP6.85. The optical light curves of both sources show substantial (~0.5-0.8 mag)...
Modelling The Galactic Bar Using Red Clump Giants (2007)
Stanek Princeton, K. Z. Stanek, A. Udalski, M. Kubiak, M. Mateo
The color-magnitude diagrams of ¸ 7 \Theta 10 5 stars obtained for 12 fields across the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump giants. We find that...
Modelling The Galactic Bar Using Red Clump Stars (2007)
Stanek Princeton, K. Z. Stanek, M. Mateo, A. Udalski, J. Ka/lu Zny, M. Kubiak
. The color-magnitude diagrams of ¸ 1\Theta10 6 stars obtained for 19 fields towards the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump stars. We found that...
Evidence For The Galactic Bar From The Two Color Photometry Of The Bulge Red Clump Stars (2007)
Stanek Princeton, K. Z. Stanek, M. Mateo, A. Udalski, M. Szyma Nski, ...
this report, for which the V \Gamma I color-magnitude diagrams were obtained by the OGLE experiment (Udalski et al. 1993, 1994b). 2. THE DATA
Results Fromthe Optical Gravitationallensing Experiment (ogle) (2007)
Paczy Nski, B. Paczy, K. Z. Stanek, A. Udalski, M. Szyma Nski, ...
. 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 ! 80 days, where t 0 =...
OGLE 2003–BLG–235/MOA 2003–BLG–53: A planetary microlensing event. (2007)
I. A. Bond, A. Udalski, M. Jaroszyński, N. J. Rattenbury, B. Paczyński, I. Soszyński, ...
(The MOA and OGLE Collaborations) 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...
A transiting planet among 23 new near-threshold candidates from the OGLE survey - OGLE-TR-182 (2007)
Pont, F., Tamuz, O., Udalski, A., Mazeh, T., Bouchy, F., Melo, C., ...
By re-processing the data of the second season of the OGLE survey for planetary transits and adding new mesurements on the same fields gathered in subsequent years with the OGLE telescope, we have...
Soszynski, I., Dziembowski, W. A., Udalski, A., Kubiak, M., Szymanski, M. K., Pietrzynski, G., ...
Period-luminosity (PL) relations of variable red giants in the Large (LMC) and Small Magellanic Clouds (SMC) are presented. The PL diagrams are plotted in three planes: logP-K_S, logP-W_{JK}, and...
INTEGRAL observations of the Small Magellanic Cloud (2007)
McBride, V. A., Coe, M. J., Bird, A. J., Dean, A. J., Hill, A. B., McGowan, K. E., ...
The first INTEGRAL observations of the Small Magellanic Cloud (carried out in 2003) are reported in which two sources are clearly detected. The first source, SMC X-1, shows a hard X-ray eclipse and...
The Cosmic Horseshoe: Discovery of an Einstein Ring around a Giant Luminous Red Galaxy (2007)
Belokurov, V., Evans, N. W., Moiseev, A., King, L. J., Hewett, P. C., Pettini, M., ...
We report the discovery of an almost complete Einstein ring of diameter 10" in Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5). Spectroscopic data from the 6m telescope of the Special...
Pietrzynski, G., Gieren, W., Udalski, A., Soszynski, I., Bresolin, F., Kudritzki, R. P., ...
We have conducted an extensive wide-field imaging survey for Cepheid variables in the Local Group irregular galaxy WLM. From data obtained on 101 nights, we have discovered 60 Cepheids which include...
An Extrasolar Planet Census with a Space-based Microlensing Survey (2007)
Bennett, D. P., Anderson, J., Bond, I., Cheng, E., Cook, K., ...
A space-based gravitational microlensing exoplanet survey will provide a statistical census of exoplanets with masses down to 0.1 Earth-masses and orbital separations ranging from 0.5AU to infinity....
Pont, F, Moutou, C, Gillon, Michaël, Udalski, A, Bouchy, F, Fernandes, J M, ...
Transiting planets are essential to study the structure and evolution of extra-solar planets. For that purpose, it is important to measure precisely the radius of these planets. Here we report new...
First Space-Based Microlens Parallax Measurement: Spitzer Observations of OGLE-2005-SMC-001 (2007)
Dong, Subo, Udalski, A., Gould, A., Reach, W. T., Christie, G. W., Boden, A. F., ...
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...
Binary Lenses in OGLE-III EWS Database. Season 2004 (2007)
Jaroszynski, M., Skowron, J., Udalski, A., Kubiak, M., Szymanski, M. K., Pietrzynski, G., ...
We present 19 binary lens candidates from OGLE-III Early Warning System database for the season of 2004. We have also found five events interpreted as single mass lensing of double sources. The...
Udalski, A., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Zebrun, K., ...
We present results of the long term monitoring of the gravitational lens QSO 2237+0305 conducted during the OGLE survey. Light curves of all four components of the lens obtained during the second...
McGowan, K. E., Coe, M. J., Schurch, M., McBride, V. A., Galache, J. L., Edge, W. R. T., ...
We investigate the X-ray and optical properties of a sample of X-ray bright sources from the Small Magellanic Cloud (SMC) Wing Survey. We have detected two new pulsars with pulse periods of 65.8 s...
Pont, F., Moutou, C., Gillon, M., Udalski, A., Bouchy, F., Fernandes, J. M., ...
Publicación ISI
Pont, F., Moutou, C., Gillon, M., Udalski, A., Bouchy, F., Fernandes, J. M., ...
Publicación ISI
Pietrzynski, G., Gieren, W., Soszynski, I., Udalski, A., Bresolin, F., ...
We have detected, for the first time, Cepheid variables in the Sculptor Group SB(s)m galaxy NGC 55. From wide-field images obtained in the optical V and I bands during 77 nights in 2002-2003, we have...
OGLE 2004-BLG-254: a K3 III Galactic Bulge Giant spatially resolved by a single microlens (2006)
Cassan, A., Fouque, P., Brillant, S., Dominik, M., Greenhill, J., ...
We present an analysis of OGLE 2004-BLG-254, a high-magnification and relatively short duration microlensing event in which the source star, a Bulge K3-giant, has been spatially resolved by a...
Wyrzykowski, L., Udalski, A., Mao, S., Kubiak, M., Szymanski, M. K., Pietrzynski, G., ...
We present the first systematic search for microlensing events with variability in their baselines using data from the third phase of the Optical Gravitational Lensing Experiment (OGLE-III). A total...
Removing the Microlensing Blending-Parallax Degeneracy Using Source Variability (2006)
Assef, R.J., Gould, A., Afonso, C., Albert, J.N., Andersen, J., Ansari, R., ...
Microlensing event MACHO 97-SMC-1 is one of the rare microlensing events for which the source is a variable star, simply because most variable stars are systematically eliminated from microlensing...
An Investigation of Be/X-ray Pulsars with OGLE-III Data (2006)
Schmidtke, P. C., Cowley, A. P., Udalski, A.
We have studied five seasons of OGLE-III data for eight SMC Be/X-ray pulsars for which no other survey data were available. We have determined orbital periods for four of these binary systems, one of...
The Araucaria Project. A Wide-Field Photometric Survey for Cepheid Variables in NGC 3109 (2006)
Pietrzynski, G., Gieren, W., Udalski, A., Soszynski, I., Bresolin, F., Kudritzki, R. P., ...
We have obtained mosaic images of NGC 3109 in the V and I bands on 74 nights, spanning approximately one year. From these data, we have conducted an extensive search for Cepheid variables over the...
Microlens OGLE-2005-BLG-169 Implies Cool Neptune-Like Planets are Common (2006)
Gould, A., Udalski, A., An, D., Bennett, D. P., Dong, S., ...
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 main-sequence star,...
Discovery of a Cool Planet of 5.5 Earth Masses Through Gravitational Microlensing (2006)
Bennett, D. P., Fouque, P., Williams, A., Dominik, M., Jorgensen, U. G., ...
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....
Removing the Microlensing Blending-Parallax Degeneracy Using Source Variability (2006)
Assef, R.J., Gould, A., Afonso, C., Albert, J.N., Andersen, J., Ansari, R., ...
Microlensing event MACHO 97-SMC-1 is one of the rare microlensing events for which the source is a variable star, simply because most variable stars are systematically eliminated from microlensing...
Removing the microlensing blending-parallax degeneracy using source variability (2006)
Assef, R. J., Gould, A., Afonso, C., Albert, J. N., Andersen, J., Ansari, R., ...
Microlensing event MACHO 97-SMC-1 is one of the rare microlensing events for which the source is a variable star, simply because most variable stars are systematically eliminated from microlensing...
Discovery of a cool planet of 5.5 Earth masses through gravitational microlensing (2006)
Beaulieu, JP, Bennett, DP, Fouque, P, Williams, A, Dominik, M, Jorgensen, UG, ...
OGLE 2004-BLG-254: a K3 III Galactic bulge giant spatially resolved by a single microlens (2006)
Cassan, A, Beaulieu, JP, Fouque, P, Brilliant, S, Dominik, M, Greenhill, JG, ...
Soszynski, I., Udalski, A., Kubiak, M., Szymanski, M. K., Pietrzynski, G., Zebrun, K., ...
We use the OGLE-II and OGLE-III data in conjunction with the 2MASS near-infrared (NIR) photometry to identify and study Miras and Semiregular Variables (SRVs) in the Large Magellanic Cloud. We found...
Potential Direct Single-Star Mass Measurement (2005)
Ghosh, H., Depoy, D.L., Gal-Yam, A., Gaudi, B.S., Gould, A., Han, C., ...
We analyze the lightcurve of the microlensing event OGLE-2003-BLG-175/MOA-2003-BLG-45 and show that it has two properties that, when combined with future high resolution astrometry, could lead to a...
A Jovian-mass Planet in Microlensing Event OGLE-2005-BLG-071 (2005)
Udalski, A., Jaroszynski, M., Paczynski, B., Kubiak, M., Szymanski, M. K., Soszynski, I., ...
We report the discovery of a several-Jupiter mass planetary companion to the primary lens star in microlensing event OGLE-2005-BLG-071. Precise (
Mass Estimates for Some of the Binary Lenses in OGLE III Database (2005)
Jaroszynski, M., Udalski, A., Kubiak, M., Szymanski, M., Pietrzynski, G., Soszynski, I., ...
We model binary microlensing events OGLE 2003-BLG-170, 267, and 291. Source angular sizes are measured for the events 267 and 291. Model fits to the light curves give parallaxes for the events 267...
OGLE-2003-BLG-238: Microlensing Mass Estimate of an Isolated Star (2005)
Jiang, Guangfei, DePoy, D. L., Gal-Yam, A., Gaudi, B. S., Gould, A., Han, C., ...
Microlensing is the only known direct method to measure the masses of stars that lack visible companions. In terms of microlensing observables, the mass is given by M=(c^2/4G)\\tilde r_E \\theta_E...
Gieren, W., Pietrzynski, G., Walker, A., Bresolin, F., Minniti, D., Kudritzki, R. P., ...
In a previous paper, we reported on the discovery of more than a hundred new Cepheid variables in the Sculptor Group spiral NGC 300 from wide-field images taken in the B and V photometric bands at...
Planetary Detection Efficiency of the Magnification 3000 Microlensing Event OGLE-2004-BLG-343 (2005)
Dong, Subo, DePoy, D. L., Gaudi, B. S., Gould, A., Han, C., ...
OGLE-2004-BLG-343 was a microlensing event with peak magnification A_{max}=3000+/-1100, by far the highest-magnification event ever analyzed and hence potentially extremely sensitive to planets...
A Jovian-mass Planet in Microlensing Event OGLE-2005-BLG-071 (2005)
Udalski, A., Jaroszynski, M., Paczynski, B., Kubiak, M., Szymanski, M. K., Soszynski, I., ...
We report the discovery of a several-Jupiter mass planetary companion to the primary lens star in microlensing event OGLE-2005-BLG-071. Precise (
The binary period and outburst behaviour of the SMC X-ray binary pulsar system SXP504 (2005)
Edge, W. R. T., Coe, M. J., Galache, J. L., McBride, V. A., Corbet, R. H. D., Okazaki, A. T., ...
A probable binary period has been detected in the optical counterpart to the X-ray source CXOU J005455.6-724510 = RX J0054.9-7245 = AXJ0054.8-7244 = SXP504 in the Small Magellanic Cloud. This source...
Microlensing optical depth toward the Galactic Bulge using bright sources from OGLE-II (2005)
Sumi, T., Wozniak, P. R., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., ...
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...
A Jovian-mass Planet in Microlensing Event OGLE-2005-BLG-071 (2005)
Udalski, A., Jaroszynski, M., Paczynski, B., Kubiak, M., Szymanski, M. K., Soszynski, I., ...
We report the discovery of a several-Jupiter mass planetary companion to the primary lens star in microlensing event OGLE-2005-BLG-071. Precise (
A Jovian-mass Planet in Microlensing Event OGLE-2005-BLG-071 (2005)
Udalski, A., Jaroszynski, M., Paczynski, B., Kubiak, M., Szymanski, M. K., Soszynski, I., ...
We report the discovery of a several-Jupiter mass planetary companion to the primary lens star in microlensing event OGLE-2005-BLG-071. Precise (
A Jovian-Mass Planet in Microlensing Event OGLE-2005-BLG-071 (2005)
Udalski, A, Jaroszynski, M, Paczynski, B, Kubiak, M, Szymanski, MK, Soszynski, I, ...
Soszynski, I., Udalski, A., Kubiak, M., Szymanski, M. K., Pietrzynski, G., Zebrun, K., ...
We used the OGLE-II and OGLE-III photometry of red giants in the Large Magellanic Cloud to select and study objects revealing ellipsoidal variability. We detected 1546 candidates for long period...
Udalski, A., Szymanski, M. K., Kubiak, M., Pietrzynski, G., Soszynski, I., Zebrun, K., ...
We present results of two observing campaigns conducted by the OGLE-III survey in the 2003 observing season aiming at the detection of new objects with planetary transiting companions. Six fields of...
The Microlensing Planet Finder: Completing the Census of Extrasolar Planets in the Milky Way (2004)
Bennett, D. P., Bond, I., Cheng, E., Friedman, S., Garnavich, P., Gaudi, B., ...
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 solar system. MPF will...
Search for Low-Mass Exoplanets by Gravitational Microlensing at High Magnification (2004)
Abe, F., Bennett, D. P., Bond, I. A., Eguchi, S., Furuta, Y., Hearnshaw, J. B., ...
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...
Pietrzynski, G., Gieren, W., Udalski, A., Bresolin, F., Kudritzki, R. P., Soszynski, I., ...
We have obtained mosaic images of NGC 6822 in V and I bands on 77 nights. From these data, we have conducted an extensive search for Cepheid variables over the entire field of the galaxy, and we have...
Binary Lenses in OGLE-III EWS Database. Seasons 2002--2003 (2004)
Jaroszynski, M., Udalski, A., Kubiak, M., Szymanski, M., Pietrzynski, G., Soszynski, I., ...
We present 15 binary lens candidates from OGLE-III Early Warning System database for seasons 2002-2003. We also found 15 events interpreted as single mass lensing of double sources. The candidates...
Curious Variables Experiment (CURVE). TT Bootis - superhump period change pattern confirmed (2004)
Olech, A., Cook, L. M., Zloczewski, K., Mularczyk, K., Kedzierski, P., Udalski, A., ...
We report extensive multi-station photometry of TT Boo during its June 2004 superoutburst. The amplitude of the superoutburst was about 5.5 mag and its length over 22 days. The star showed a small...
A first-overtone RR Lyrae star with cyclic period changes (2004)
Derekas, A., Kiss, L. L., Udalski, A., Bedding, T. R., Szatmary, K.
A detailed light curve analysis is presented for a first-overtone RR Lyrae star, MACHO* J050918.712-695015.31, based on MACHO and OGLE-III observations. As a foreground object of the Large Magellanic...
Variability-selected QSO candidates in OGLE-II Galactic Bulge fields (2004)
Sumi, T., Wozniak, P. R., Eyer, L., Dobrzycki, A., Udalski, A., Szymanski, M. K., ...
We present 97 QSO candidates in 48 Galactic Bulge fields of the Optical Gravitational Lensing Experiment II (OGLE-II) covering about 11 square degrees, which are selected via their variability. We...
Soszynski, I., Udalski, A., Kubiak, M., Szymanski, M., Pietrzynski, G., Zebrun, K., ...
We present analysis of the large sample of variable red giants from the Large and Small Magellanic Clouds detected during the second phase of the Optical Gravitational Lensing Experiment (OGLE-II)...
Gieren, W., Pietrzynski, G., Walker, A., Bresolin, F., Minniti, D., Kudritzki, R. P., ...
In a previous paper, we reported on the discovery of more than a hundred new Cepheid variables in the Sculptor Group spiral NGC 300 from wide-field images taken in the B and V photometric bands at...
Bonanos, A. Z., Stanek, K. Z., Udalski, A., Wyrzykowski, L., Zebrun, K., Kubiak, M., ...
We present a high-precision I-band light curve for the Wolf-Rayet binary WR 20a, obtained as a sub-project of the Optical Gravitational Lensing Experiment. Rauw et al. have recently presented...
Wyrzykowski, L., Udalski, A., Kubiak, M., Szymanski, M. K., Zebrun, K., Soszynski, I., ...
We present new version of the OGLE-II catalog of eclipsing binary stars detected in the Small Magellanic Cloud, based on Difference Image Analysis catalog of variable stars in the Magellanic Clouds...
OGLE-2003-BLG-238: Microlensing Mass Estimate of an Isolated Star (2004)
Jiang, Guangfei, DePoy, D. L., Gal-Yam, A., Gaudi, B. S., Gould, A., Han, C., ...
Microlensing is the only known direct method to measure the masses of stars that lack visible companions. In terms of microlensing observables, the mass is given by M=(c^2/4G)\tilde r_E \theta_E and...
OGLE 2003-BLG-235/MOA 2003-BLG-53: A planetary microlensing event (2004)
Bond, I. A., Udalski, A., Jaroszynski, M., Rattenbury, N. J., Paczynski, B., Soszynski, I., ...
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 a single lens...
Yoo, Jaiyul, DePoy, D. L., Gal-Yam, A., Gaudi, B. S., Gould, A., Han, C., ...
We develop a new method of modeling microlensing events based on a Monte Carlo simulation that incorporates both a Galactic model and the constraints imposed by the observed characteristics of the...
We describe three real time data analysis systems implemented during the third phase of the OGLE survey (OGLE-III). The EWS system is designed to detect on-going microlensing events. The EEWS system...
Potential Direct Single-Star Mass Measurement (2004)
Ghosh, H., Depoy, D.L., Gal-Yam, A., Gaudi, B.S., Gould, A., Han, C., ...
We analyze the lightcurve of the microlensing event OGLE-2003-BLG-175/MOA-2003-BLG-45 and show that it has two properties that, when combined with future high resolution astrometry, could lead to a...
OGLE-2003-BLG-238: Microlensing Mass Estimate of an Isolated Star (2004)
Jiang, Guangfei, DePoy, D. L., Gal-Yam, A., Gaudi, B. S., Gould, A., Han, C., ...
Microlensing is the only known direct method to measure the masses of stars that lack visible companions. In terms of microlensing observables, the mass is given by M=(c^2/4G)\\tilde r_E \\theta_E...
Gieren, W., Pietrzynski, G., Walker, A., Bresolin, F., Minniti, D., Kudritzki, R. P., ...
In a previous paper, we reported on the discovery of more than a hundred new Cepheid variables in the Sculptor Group spiral NGC 300 from wide-field images taken in the B and V photometric bands at...
Potential Direct Single-Star Mass Measurement (2004)
Ghosh, H., Depoy, D.L., Gal-Yam, A., Gaudi, B.S., Gould, A., Han, C., ...
We analyze the lightcurve of the microlensing event OGLE-2003-BLG-175/MOA-2003-BLG-45 and show that it has two properties that, when combined with future high resolution astrometry, could lead to a...
OGLE-2003-BLG-238: Microlensing Mass Estimate of an Isolated Star (2004)
Jiang, Guangfei, DePoy, D. L., Gal-Yam, A., Gaudi, B. S., Gould, A., Han, C., ...
Microlensing is the only known direct method to measure the masses of stars that lack visible companions. In terms of microlensing observables, the mass is given by M=(c^2/4G)\\tilde r_E \\theta_E...
Gieren, W., Pietrzynski, G., Walker, A., Bresolin, F., Minniti, D., Kudritzki, R. P., ...
In a previous paper, we reported on the discovery of more than a hundred new Cepheid variables in the Sculptor Group spiral NGC 300 from wide-field images taken in the B and V photometric bands at...
OGLE-2003-BLG-238: Microlensing Mass Estimate of an Isolated Star (2004)
Jiang, G, DePoy, DL, Gal-Yam, A, Gaudi, BS, Gould, A, Han, C, ...
Potential Direct Single-Star Mass Measurement (2004)
Ghosh, H, DePoy, DL, Gal-Yam, A, Gaudi, BS, Gould, A, Han, C, ...
Wyrzykowski, L., Udalski, A., Schechter, P. L., Szewczyk, O., Szymanski, M., Kubiak, M., ...
We present results of the long term monitoring of the gravitationally lensed quasar HE1104-1805. The photometric data were collected between August 1997 and January 2002 as a subproject of the OGLE...
Beta Cephei and SPB stars in the Large Magellanic Cloud (2003)
Kolaczkowski, Z., Pigulski, A., Soszynski, I., Udalski, A., Szymanski, M., Kubiak, M., ...
This is a progress report of the study of pulsating main-sequence stars in the LMC. Using the OGLE-II photometry supplemented by the MACHO photometry, we find 64 Beta Cephei stars in the LMC. Their...
OGLE-2003-BLG-262: Finite-Source Effects from a Point-Mass Lens (2003)
Yoo, Jaiyul, DePoy, D. L., Gal-Yam, A., Gaudi, B. S., Gould, A., Han, C., ...
We analyze OGLE-2003-BLG-262, a relatively short, t_E=12.5+-0.1day, microlensing event generated by a point-mass lens transiting the face of a K giant source in the Galactic bulge. We use the...
The Optical Gravitational Lensing Experiment. Population II Cepheids in the Galactic Bulge (2003)
We present I-band light curves of 54 Population II Cepheids identified in the OGLE-II catalog of variable objects in the Galactic bulge fields. Their periods range from a fraction of a day to several...
Udalski, A., Pietrzynski, G., Szymanski, M., Kubiak, M., Zebrun, K., Soszynski, I., ...
The photometric data collected by OGLE-III during the 2001 and 2002 observational campaigns aiming at detection of planetary or low-luminosity object transits were corrected for small scale...
Soszynski, I., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., ...
We present the catalog of RR Lyrae stars discovered in a 4.5 square degrees area in the central parts of the Large Magellanic Cloud (LMC). Presented sample contains 7612 objects, including 5455...
Sumi, T., Wu, X., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., ...
We present a proper motion (\mu) catalogue of 5,080,236 stars in 49 Optical Gravitational Lensing Experiment II (OGLE-II) Galactic bulge (GB) fields, covering a range of -11 deg.
Wyrzykowski, L., Udalski, A., Kubiak, M., Szymanski, M., Zebrun, K., Soszynski, I., ...
We present the catalog of 2580 eclipsing binary stars detected in 4.6 square degree area of the central parts of the Large Magellanic Cloud. The photometric data were collected during the second...
Pietrzy{ń}ski, G., Gieren, W., Udalski, A.
(Abridged) We present results of deep near-infrared JK imaging of LMC, SMC, and the Carina and Fornax dwarf galaxies. A comparison of the extinction-corrected K-band red clump star magnitudes with...
Udalski, A., Szewczyk, O., Zebrun, K., Pietrzynski, G., Szymanski, M., Kubiak, M., ...
We present results of the second planetary and low-luminosity object transit campaign conducted by the OGLE-III survey. Three fields (35'x35' each) located in the Carina regions of the Galactic disk...
Soszynski, I., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., ...
We present the catalog of RR Lyrae stars from 2.4 square degrees of central parts of the Small Magellanic Cloud (SMC). The photometric data were collected during four years of the OGLE-II...
Photometry of the Galactic bulge, collected during the OGLE-II microlensing search, indicates high and non-uniform interstellar extinction toward the observed fields. We use the mean I-band magnitude...
Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Soszynski, I., Wozniak, P., ...
We present the VI photometric maps of the Galactic bulge. They contain VI photometry and astrometry of about 30 million stars from 49 fields of 0.225 square degree each in the Galactic center region....
Udalski, A., Zebrun, K., Szymanski, M., Kubiak, M., Soszynski, I., Szewczyk, O., ...
The photometric data collected during 2001 season OGLE-III planetary/low luminosity object transit campaign were reanalyzed with the new transit search technique -- the BLS method by Kovacs, Zucker...
Smith, M. C., Mao, S., Wozniak, P., Udalski, A., Szymanski, M., Kubiak, M., ...
We describe a highly unusual microlensing event, OGLE-1999-BUL-19, which exhibits multiple peaks in its light curve. The Einstein radius crossing time for this event is approximately one year, which...
Microlensing of Relativistic Knots in the Quasar HE1104-1805 (2002)
Schechter, Paul L., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Soszynski, I., ...
We present 3 years of photometry of the ``Double Hamburger'' lensed quasar, HE1104-1805, obtained on 102 separate nights using the OGLE 1.3-m telescope. Both the A and B images show variations, but...
Soszynski, I., Zebrun, K., Udalski, A., Wozniak, P. R., Szymanski, M., Kubiak, M., ...
We present a Catalog of high proper motion (HPM) stars detected in the foreground of central parts of the Magellanic Clouds. The Catalog contains 2161 objects in the 4.5 square degree area towards...
Pietrzynski, G., Gieren, W., Udalski, A.
Based on 13 nights of observations of four fields in NGC 300, we have set up an extensive sequence of stars with accurate BVI photometry covering a relatively large (25 x 25 arcmin) region centered...
Udalski, A., Paczynski, B., Zebrun, K., Szymanski, M., Kubiak, M., Soszynski, I., ...
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 Gravitational Lensing...
Wozniak, P. R., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Soszynski, I., ...
We present the first edition of a catalog of variable stars from OGLE-II Galactic Bulge data covering 3 years: 1997-1999. Typically 200-300 I band data points are available in 49 fields between -11...
Zebrun, K., Soszynski, I., Wozniak, P. R., Udalski, A., Kubiak, M., Szymanski, M., ...
We present the first edition of a catalog of variable stars found in the Magellanic Clouds using OGLE-II data obtained during four years: 1997-2000. The catalog covers about 7 square degrees of the...
Contact Binaries in OGLE-I Database (2001)
Szymanski, M., Kubiak, M., Udalski, A.
We present a new catalog of 1575 contact binary stars fainter than I=18 mag identified in OGLE-I database in the selected directions toward the Galactic bulge and the Galactic bar. For completeness...
Udalski, A., Wyrzykowski, L., Pietrzynski, G., Szewczyk, O., Szymanski, M., Kubiak, M., ...
We present results of the search for Cepheids in the galaxy IC1613 carried out as a sub-project of the OGLE-II microlensing survey. 138 Cepheids were found in the 14.2x14.2 arcmin region in the...
Mao, Shude, Smith, Martin C., Wozniak, P., Udalski, A., Kubiak, M. Szymanski M., Pietrzynski, G., ...
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...
Difference Image Analysis of the OGLE-II bulge data. II. Microlensing events (2001)
Wozniak, P. R., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Soszynski, I., ...
We present a sample of microlensing events discovered in the Difference Image Analysis (DIA) of the OGLE-II images collected during 3 observing seasons, 1997--1999. 4424 light curves pass our...
Soszynski, I., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., ...
We present a sample of 76 double-mode Cepheids detected in the 4.5 square degree area in the central part of the LMC. 19 stars from the sample pulsate in the fundamental mode and the first overtone...
Soszynski, I., Zebrun, K., Wozniak, P. R., Mao, S., Udalski, A., Szymanski, M., ...
We present the photometry and theoretical models for a Galactic bulge microlensing event OGLE-2000-BUL-43. The event is very bright with I=13.54 mag, and has a very long time scale, t_E=156 days. The...
The Optical Gravitational Lensing Experiment. Ages of about 600 Star Clusters from the LMC (2000)
We present results of age determination based on the standard procedure of isochrone fitting for about 600 star clusters younger than about 1.2 Gyr from the central parts of the LMC. Comparison of...
We present 100 multiple cluster candidates selected from the OGLE catalog of star clusters in the Large Magellanic Cloud. Statistical analysis shows that the significant fraction of these objects may...
Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Soszynski, I., Wozniak, P., ...
We present the BVI photometric maps of the Large Magellanic Cloud. They contain BVI photometry and astrometry of more than 7 million stars from the central parts of the LMC. The data were collected...
BVI photometry of the Magellanic Clouds collected during the OGLE-II microlensing experiment makes it possible to study in detail photometric properties of the "major" stellar distance indicators in...
The Optical Gravitational Lensing Experiment. A Hunt for Caustic Crossings in QSO 2237+0305 (2000)
Wozniak, P. R., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Soszynski, I., ...
In 1998 The Optical Gravitational Lensing Experiment (OGLE) successfully implemented automated data reductions for QSO 2237+0305. Using a new image subtraction method we achieved a differential...
Udalski, A., Zebrun, K., Szymanski, M., Kubiak, M., Pietrzynski, G., Soszynski, I., ...
We present the Catalog of microlensing events detected toward the Galactic bulge in three observing seasons, 1997--1999, during the OGLE-II microlensing survey. The search for microlensing events was...
Combined Analysis of the Binary Lens Caustic-Crossing Event MACHO 98-SMC-1 (2000)
Afonso, C, Alard, C, Albert, JN, Andersen, J, Ansari, R, Aubourg, E, ...
Pietrzynski, G., Udalski, A., Kubiak, M., Szymanski, M., Wozniak, P., Zebrun, K.
We present the catalog of star clusters found in the area of about 5.8 square degree in the central regions of the Large Magellanic Cloud. It contains data for 745 clusters. 126 of them are new...
We present Cepheids located in the close neighborhood of star clusters from the Magellanic Clouds. 204 and 132 such stars were found in the LMC and SMC, respectively. The lists of objects were...
Udalski, A., Soszynski, I., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., ...
We present the Catalog of Cepheids from the SMC which contains data for 2049 objects detected in the 2.4 square degree area of central parts of the SMC. For each object period, BVI photometry,...
The Optical Gravitational Lensing Experiment. Red Clump Stars as a Distance Indicator (1999)
We present relation of the mean I-band brightness of red clump stars on metallicity. Red clump stars were proposed to be a very attractive standard candle for distance determination. The calibration...
We investigate the influence of blending on the Cepheid distance scale. Blending leads to systematically low distances to galaxies observed with HST, and therefore to systematically high estimates of...
Udalski, A., Soszynski, I., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., ...
We present the Catalog of Cepheids from the LMC. The Catalog contains 1333 objects detected in the 4.5 square degree area of central parts of the LMC. About 3.4*10^5 BVI measurements of these stars...
The Optical Gravitational Lensing Experiment. UBVI Photometry of Stars in Baade's Window (1999)
Paczynski, B., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Soszynski, I., ...
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 photometry with...
Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Soszynski, I., Wozniak, P., ...
We present Period-Luminosity-Color and Period-Luminosity relations of classical Cepheids constructed for about 1280 Cepheids from the LMC and 2140 from the SMC. High quality BVI observations (120-360...
The Optical Gravitational Lensing Experiment. Age of Star Clusters from the SMC (1999)
We present determination of age of clusters from 2.4 square degree region of the SMC bar. The photometric data were taken from the BVI maps of the SMC and catalog of clusters in this galaxy obtained...
We present the list of potential multiple star clusters from the central part of the SMC. Presented systems were selected from the catalog of star clusters from the SMC. We find 23 suspected cluster...
The list of 127 eclipsing stars in optical coincidence with star clusters from the SMC is presented. It was prepared using the catalogs of eclipsing systems and star clusters from the SMC based on...
The Optical Gravitational Lensing Experiment. Monitoring of QSO 2237+0305 (1999)
Wozniak, P. R., Alard, C., Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., ...
We present results from 2 years of monitoring of Huchra's lens (QSO 2237+0305) with the 1.3 m Warsaw telescope on Las Campanas, Chile. Photometry in the V band was done using a newly developed method...
Udalski, A., Soszynski, I., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., ...
We present a sample of 93 double-mode Cepheids detected in the 2.4 square degree area in the central part of the SMC. 23 stars from the sample pulsate in the fundamental mode and the first overtone...
Udalski, A., Soszynski, I., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., ...
We present a sample of 13 candidates for single-mode second overtone Cepheids discovered in the 2.4 square degree area of the SMC bar during the OGLE microlensing search. All candidates passed four...
Udalski, A., Soszynski, I., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., ...
We present the catalog of 1459 eclipsing binary stars detected in the central 2.4 square degree area of the Small Magellanic Cloud during the OGLE-II microlensing search. The sample includes objects...
The Optical Gravitational Lensing Experiment. Short Distance Scale to the LMC (1998)
Udalski, A., Pietrzynski, G., Wozniak, P., Szymanski, M., Kubiak, M., Zebrun, K.
We present {\it UBVI} photometry of the eclipsing binary HV2274 - the system which has been recently used for distance determination to the LMC by Guinan et al. (1998). We determine the interstellar...
Udalski, A., Kubiak, M., Szymanski, M., Pietrzynski, G., Wozniak, P., Zebrun, K.
We present photometry of the unique binary microlensing event MACHO-SMC-98-1 collected by the OGLE group. Particularly interesting observation was made close to the first caustic crossing which was...
We present an empirical test indicating that the mean I-band magnitude of the red clump stars, used as the standard candle in the recent distance determinations to the Magellanic Clouds and other...
Pietrzynski, G., Udalski, A., Kubiak, M., Szymanski, M., Wozniak, P., Zebrun, K.
We present the catalog of clusters found in the area of ~2.4 square degree in the central regions of the Small Magellanic Cloud. The catalog contains data for 238 clusters, 72 of them are new...
Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., Zebrun, K.
We present three color, BVI maps of the Small Magellanic Cloud. The maps contain precise photometric and astrometric data for about 2.2 million stars from the central regions of the SMC bar covering...
Optical Gravitational Lensing Experiment. The Distance Scale: Galactic Bulge - LMC - SMC (1998)
We analyze the mean luminosity of three samples of field RRab Lyr stars observed in the course of the OGLE microlensing experiment: 73 stars from the Galactic bulge and 110 and 128 stars from...
Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., Zebrun, K.
We present a new distance determination to the Large and Small Magellanic Clouds using the newly developed red clump stars method (Paczynski and Stanek 1998). This new, single-step, Hipparcos...
Udalski, A., Szymanski, M., Kubiak, M., Pietrzynski, G., Wozniak, P., Zebrun, K.
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...
Optical Gravitational Lensing Experiment. OGLE-2 -- the Second Phase of the OGLE Project (1997)
Udalski, A., Kubiak, M., Szymanski, M.
We describe a new 1.3 m Warsaw telescope located at Las Campanas Observatory and new instruments of the second phase of the Optical Gravitational Lensing Experiment - OGLE-2. Results of first...
Kaluzny, J., Kubiak, M., Szymanski, M., Udalski, A., Krzeminski, W., Mateo, M., ...
Five fields located close to the center of the globular cluster NGC 104=47 Tuc were surveyed in a search for variable stars. We present V-band light curves for 42 variables. This sample includes 13...
Udalski, A., Olech, A., Szymanski, M., Kaluzny, J., Kubiak, M., Mateo, M., ...
We present the fifth part of the OGLE Catalog of Periodic Variable Stars in the Galactic bulge. 574 variable stars: 44 pulsating, 369 eclipsing and 161 miscellaneous type were detected in four fields...
Modelling the Galactic Bar Using Red Clump Giants (1996)
Stanek, K. Z., Udalski, A., Szymanski, M., Kaluzny, J., Kubiak, M., Mateo, M., ...
The color-magnitude diagrams of $\sim 7 \times 10^5$ stars obtained for 12 fields across the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump giants. We find...
Szymanski, M., Udalski, A., Kubiak, M., Kaluzny, J., Mateo, M., Krzeminski, W.
This paper presents the first part of the Optical Gravitational Lensing Experiment (OGLE) General Catalog of Stars in the Galactic bulge. The Catalog is based on observations collected during the...
Kaluzny, J., Kubiak, M., Szymanski, M., Udalski, A., Krzeminski, W., Mateo, M., ...
Three fields located close to the center of the globular cluster Omega Cen were surveyed in a search for variable stars. We present V-band light curves for 32 periodic variables. This sample includes...
Kaluzny, J., Kubiak, M., Szymanski, M., Udalski, A., Krzeminski, W., Mateo, M.
Three fields covering the central part of the globular cluster Omega Cen were surveyed in a search for variable stars. We present V-band light curves for 22 periodic variables: 9 SX~Phe stars, 7...
Modelling the Galactic Bar Using Red Clump Stars (1995)
Stanek, K. Z., Mateo, M., Udalski, A., Szymanski, M., Kaluzny, J., Kubiak, M., ...
The color-magnitude diagrams of $\sim 1 \times 10^6$ stars obtained for 19 fields towards the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump stars. We found...
Kaluzny, J., Kubiak, M., Szymanski, M., Udalski, A., Krzeminski, W., Mateo, M.
Extensive monitoring of the central part of Omega Cen has lead to the discovery of 12 eclipsing binaries and 9 SX~Phe stars. We report also finding 6 contact binaries in the field of 47~Tuc.
UDALSKI, A., SZYMANSKI, M., KALUZNY, J., KUBIAK, M., MATEO, M., KRZEMINSKI, W.
We present the second part of the OGLE Catalog of Periodic Variable Stars in the Galactic bulge. 800 variable stars found in four Baade's Window fields BW1, BW2, BW3 and BW4 are presented. Among them...
UDALSKI, A., KUBIAK, M., SZYMANSKI, M., KALUZNY, J., MATEO, M., KRZEMINSKI, W.
This paper is the first part of the Catalog of Periodic Variable Stars in the Galactic bulge. The Catalog is based on observations collected during the OGLE microlensing search. 213 periodic variable...
Szymanski, M., Udalski, A., Kaluzny, J., Kubiak, M., Krzeminski, W., Mateo, M.
We present follow-up observations of a gravitational microlensing candidate found by the MACHO collaboration in the Galactic bulge. The photometric data cover a period near the maximum of the event...
Kaluzny, J., Kubiak, M., Szymanski, M., Udalski, A., Krzeminski, W., Mateo, M.
The central area of the Sculptor dwarf galaxy was surveyed for variable stars as a side-program of the OGLE project. Light curves in the V band were obtained for 226 RR Lyr stars and for 3 anomalous...
Results from the Optical Gravitational Lensing Experiment (OGLE) (1994)
Paczynski, B., Stanek, K. Z., Udalski, A., Szymanski, M., Kaluzny, J., Kubiak, M., ...
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 < 80 $ days, where $...
Evidence for the Galactic Bar from the Two Color Photometry of the Bulge Red Clump Stars (1994)
Stanek, K. Z., Mateo, M., Udalski, A., Szymanski, M., Kaluzny, J., Kubiak, M., ...
The Optical Gravitational Lensing Experiment (OGLE, Udalski et al.~1994a; Paczy\'nski et al.~1994b -- these proceedings; and references therein) is an extensive photometric search for the rare cases...
Mateo, Mario, Udalski, A., Szymanski, M., Kaluzny, J., Kubiak, M., Krzeminski, W.
We present deep CCD photometry of a field in the newly discovered dwarf spheroidal galaxy in Sagittarius (hereafter Sgr), and of a nearby control field. These data (totaling ~3.5 hrs exposure time in...
The Optical Gravitational Lensing Experiment. the Early Warning System (1994)
Udalski, A., Szymanski, M., Kaluzny, J., Kubiak, M., Mateo, M., Krzeminski, W., ...
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 Galactic bulge and...
Udalski, A., Szymanski, M., Mao, S., Di Stefano, R., Kaluzny, J., Kubiak, M., ...
We present the light curve of an unusual variable object, OGLE #7, detected during the OGLE search for microlensing events. After one season of being in a low, normal state, the star brightened by...
The Optical Depth to Gravitational Microlensing in the Direction of the Galactic Bulge (1994)
Udalski, A., Szymanski, M., Stanek, K. Z., Kaluzny, J., Kubiak, M., Mateo, M., ...
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 $...
Are the Ogle Microlenses in the Galactic Bar? (1994)
Paczynski, B., Stanek, K. Z., Udalski, A., Szymanski, M., Kaluzny, J., Kubiak, M., ...
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 $ 8.6 < t_0 < 62 $ days, where $ t_0 =...
Stanek, K. Z., Mateo, M., Udalski, A., Szymanski, M., Kaluzny, J., Kubiak, M.
The color-magnitude diagrams of $\sim 5\times 10^5$ stars obtained for 13 fields towards the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump stars. We find...
The Distribution of Galactic Disk Stars in Baade's Window (1994)
Paczynski, B., Stanek, K. Z., Udalski, A., Szymanski, M., Kaluzny, J., Kubiak, M., ...
The color-magnitude diagram of $ \sim 3 \times 10^5 $ stars obtained for Baade's Window towards the Galactic bulge with the OGLE project reveals a surprisingly narrow main sequence due to galactic...