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...
Upper Limits on the Number of Small Bodies in Sedna-Like Orbits by the TAOS Project (2009)
Lehner, M. J., Bianco, F. B., Alcock, C., ...
We present the results of a search for occultation events by objects at distances between 100 and 1000 AU in lightcurves from the Taiwanese-American Occultation Survey (TAOS). We searched for...
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-2005-BLG-071Lb, the Most Massive M Dwarf Planetary Companion? (2009)
Dong, Subo, Gould, Andrew, Udalski, Andrzej, Anderson, Jay, Christie, G. W., Gaudi, B. S., ...
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, 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,...
A Close Binary Star Resolved from Occultation by 87 Sylvia (2009)
Lin, Chi-Long, Zhang, Zhi-Wei, Chen, W. P., King, Sun-Kun, Lin, Hung-Chin, ...
The star BD +29 1748 was resolved to be a close binary from its occultation by the asteroid 87 Sylvia on 2006 December 18 UT. Four telescopes were used to observe this event at two sites separated by...
The MACHO Project HST Follow-Up: The Large Magellanic Cloud Microlensing Source Stars (2009)
Nelson, C. A., Drake, A. J., Cook, K. H., Bennett, D. P., Popowski, P., Dalal, N., ...
We present Hubble Space Telescope (HST) WFPC2 photometry of 13 microlensed source stars from the 5.7 year Large Magellanic Cloud (LMC) survey conducted by the MACHO Project. The microlensing source...
The Taiwanese-American Occultation Survey : the multi-telescope robotic observatory (2009)
Lehner, M. J., Marshall, S. L., Schwamb, M. E., ...
The Taiwanese-American Occultation Survey (TAOS) operates four fully automatic telescopes to search for occultations of stars by Kuiper Belt Objects. It is a versatile facility that is also useful...
A Close Binary Star Resolved from Occultation by 87 Sylvia (2009)
Lin, Chi-Long, Zhang, Zhi-Wei, Chen, W. P., King, Sun-Kun, Lin, Hung-Chin, Bianco, F. B., ...
The star BD+29 1748 was resolved to be a close binary from its occultation by the asteroid 87 Sylvia on 2006 December 18 UT. Four telescopes were used to observe this event at two sites separated by...
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...
First Results from the Taiwanese-American Occultation Survey (TAOS) (2008)
Bianco, F. B., Lehner, M. J., Coehlo, N. K., Mondal, S., ...
Results from the first 2 years of data from the Taiwanese-American Occultation Survey (TAOS) are presented. Stars have been monitored photometrically at 4 or 5 Hz to search for occultations by small...
First Results From The Taiwanese-American Occultation Survey (TAOS) (2008)
Bianco, F. B., Lehner, M. J., Coehlo, N. K., Mondal, S., ...
Results from the first two years of data from the Taiwanese-American Occultation Survey (TAOS) are presented. Stars have been monitored photometrically at 4 Hz or 5 Hz to search for occultations by...
Rest, A., Welch, D. L., Suntzeff, N. B., Oaster, L., Lanning, H., Olsen, K., ...
We report the discovery of an extensive system of scattered light echo arclets associated with the recent supernovae in the local neighbourhood of the Milky Way: Tycho (SN 1572) and Cassiopeia A....
Early optical brightening in GRB 071010B (2008)
Wang, J. H., Schwamb, M. E., Huang, K. Y., Wen, C. Y., Zhang, Z. W., Wang, S. Y., ...
We report the detection of early (60-230 s) optical emission of the gamma-ray burst afterglow of GRB 071010B. No significant correlation with the prompt γ-ray emission was found. Our high time...
OGLE-2005-BLG-071Lb, the Most Massive M-Dwarf Planetary Companion? (2008)
Dong, Subo, Gould, Andrew, Udalski, Andrzej, Anderson, Jay, Christie, G. W., Gaudi, B. S., ...
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...
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...
The Taiwanese-American Occultation Survey: The Multi-Telescope Robotic Observatory (2008)
Lehner, M. J., Marshall, S. L., Schwamb, M. E., ...
The Taiwanese-American Occultation Survey (TAOS) operates four fully automatic telescopes to search for occultations of stars by Kuiper Belt Objects. It is a versatile facility that is also useful...
Spectral Identification of an Ancient Supernova using Light Echoes in the LMC (2008)
Rest, A., Matheson, T., Blondin, S., Bergmann, M., Welch, D. L., Suntzeff, N. B., ...
We report the successful identification of the type of the supernova responsible for the supernova remnant SNR 0509-675 in the Large Magellanic Cloud (LMC) using Gemini spectra of surrounding light...
Cepheids in the Magellanic Clouds (2007)
D. L. Welch, C. Alcock, D.P. Bennett, K.H. Cook, A. W. Rodgers, K. Griest, ...
. In the past few years, the Magellanic Clouds have been the targets for several major variable star surveys. The results of these surveys are now becoming available and it is clear that a...
The MACHO Project LMC Variable Star Inventory: IV. New R Coronae Borealis Stars (2007)
Alcock Allsman, C. Alcock, D. R. Alves, A. Becker, D. P. Bennett, K. H. Cook, ...
We report the discovery of two new R Coronae Borealis (RCB) stars in the Large Magellanic Cloud (LMC) using the MACHO project photometry database. The identification of both stars has been confirmed...
Rr Lyrae Stars In The Macho Database (2007)
Minniti Alcock, D. Minniti, C. Alcock, D. P. Bennett, K. H. Cook, K. C. Freeman, ...
The MACHO Project has catalogued ¸ 8000 RR Lyrae stars in the Large Magellanic Cloud, ¸ 1800 in the Galactic bulge, and ¸ 50 in the Sgr dwarf galaxy. These variables are excellent distance...
Mario Mateo, Edward W. Olszewski, K. H. Cook
The High Resolution Echelle Spectrometer on the Keck I telescope has been used to measure nine radial velocities having a median precision of ' 2 km s 1 for seven red giants belonging to the...
Miceli, A., Rest, A., Stubbs, C. W., Hawley, S. L., Cook, K. H., Magnier, E. A., ...
We present 838 ab-type RR Lyrae stars from the Lowell Observatory Near Earth Objects Survey Phase I (LONEOS-I). These objects cover 1430 deg^2 and span distances ranging from 3-30 kpc from the...
Determination of stellar shape in microlensing event MOA 2002-BLG-33 (2006)
Rattenbury, N.J., Abe, F., Bennett, D.P., Bond, I.A., Calitz, J.J., Claret, A., ...
We report a measurement of the shape of the source star in microlensing event MOA 2002-BLG-33. The lens for this event was a close binary whose centre-of-mass passed almost directly in front of the...
Determination of stellar shape in microlensing event MOA 2002-BLG-33 (2006)
Rattenbury, N.J., Abe, F., Bennett, D.P., Bond, I.A., Calitz, J.J., Claret, A., ...
We report a measurement of the shape of the source star in microlensing event MOA 2002-BLG-33. The lens for this event was a close binary whose centre-of-mass passed almost directly in front of the...
Determination of stellar shape in microlensing event MOA 2002-BLG-33 (2006)
Rattenbury, N.J., Abe, F., Bennett, D.P., Bond, I.A., Calitz, J.J., Claret, A., ...
We report a measurement of the shape of the source star in microlensing event MOA 2002-BLG-33. The lens for this event was a close binary whose centre-of-mass passed almost directly in front of the...
Search for Small Trans-Neptunian Objects by the TAOS Project (2006)
Chen, W. P., Alcock, C., Axelrod, T., Bianco, F. B., Byun, Y. I., Chang, Y. H., ...
The Taiwan-America Occultation Survey (TAOS) aims to determine the number of small icy bodies in the outer reach of the Solar System by means of stellar occultation. An array of 4 robotic small...
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....
Rest, A., Stubbs, C., Becker, A. C., Miknaitis, G. A., Miceli, A., Covarrubias, R., ...
Characterizing the nature and spatial distribution of the lensing objects that produce the previously measured microlensing optical depth toward the Large Magellanic Cloud (LMC) remains an open...
Discovery of Five New R Coronae Borealis Stars in the MACHO Galactic Bulge Database (2005)
Zaniewski, A., Clayton, Geoffrey C., Welch, D. L., Gordon, Karl D., Minniti, D., Cook, K. H.
We have identified five new R Coronae Borealis (RCB) stars in the Galactic bulge using the MACHO Project photometry database, raising the total number of known Galactic RCB stars to about 40. We have...
Determination of stellar shape in microlensing event MOA 2002-BLG-33 (2005)
Rattenbury, N. J., Abe, F., Bennett, D. P., Bond, I. A., Calitz, J. J., Claret, A., ...
We report a measurement of the shape of the source star in microlensing event MOA 2002-BLG-33. The lens for this event was a close binary whose centre-of-mass passed almost directly in front of the...
Determination of stellar shape in microlensing event MOA 2002-BLG-33 (2005)
Rattenbury, N.J., Abe, F., Bennett, D.P., Bond, I.A., Calitz, J.J., Claret, A., ...
We report a measurement of the shape of the source star in microlensing event MOA 2002-BLG-33. The lens for this event was a close binary whose centre-of-mass passed almost directly in front of the...
Determination of stellar shape in microlensing event MOA 2002-BLG-33 (2005)
Rattenbury, N.J., Abe, F., Bennett, D.P., Bond, I.A., Calitz, J.J., Claret, A., ...
We report a measurement of the shape of the source star in microlensing event MOA 2002-BLG-33. The lens for this event was a close binary whose centre-of-mass passed almost directly in front of the...
Microlensing optical depth toward the galactic bulge using clump giants from the MACHO survey (2005)
Popowski, P., Griest, K., Thomas, C. L., Cook, K. H., Bennett, D. P., Becker, A. C., ...
Galactic bulge microlensing events from the MACHO Collaboration (2005)
Thomas, C. L., Griest, K., Popowski, P., Cook, K. H., Drake, A. J., Minniti, D., ...
Extinction toward the galactic bulge from RR Lyrae stars (2005)
Kunder, A. M., Popowski, P., Cook, K. H., Nikolaev, S., Chaboyer, B.
Popowski, P., Griest, K., Thomas, C. L., Cook, K. H., Bennett, D. P., Becker, A. C., ...
Using 7 years of MACHO survey data, we present a new determination of the optical depth to microlensing towards the Galactic bulge. We select the sample of 62 microlensing events (60 unique) on clump...
Galactic Bulge Microlensing Events from the MACHO Collaboration (2004)
Thomas, C. L., Griest, K., Popowski, P., Cook, K. H., Drake, A. J., Minniti, D., ...
We present a catalog of 450 high signal-to-noise microlensing events observed by the MACHO collaboration between 1993 and 1999. The events are distributed throughout our fields and, as expected, they...
The SuperMACHO Microlensing Survey (2004)
Becker, A. C., Rest, A., Stubbs, C., Miknaitis, G. A., Miceli, A., Covarrubias, R., ...
We present the first results from our next-generation microlensing survey, the SuperMACHO project. We are using the CTIO 4m Blanco telescope and the MOSAIC imager to carry out a search for...
Properties of RR Lyrae stars in the Inner Regions of the Large Magellanic Cloud (2004)
Borissova, J., Minniti, D., Rejkuba, M., Alves, D., Cook, K. H., Freeman, K. C.
We present the radial velocities, metallicities and the K-band magnitudes of 74 RR Lyrae stars in the inner regions of the LMC. The intermediate resolution spectra and infrared images were obtained...
Resolving the Nature of the LMC Microlensing Event LMC-5 (2004)
Drake, A. J., Cook, K. H., Keller, S. C.
We present the results from an analysis of Hubble Space Telescope High Resolution Camera data for the Large Magellanic Cloud microlensing event MACHO-LMC-5. By determining the parallax and proper...
Probing the atmosphere of a solar-like star by galactic microlensing at high magnification (2003)
Abe, F., Bennett, D. P., Bond, I. A., Calitz, J. J., Claret, A., Cook, K. H., ...
We report a measurement of limb darkening of a solar-like star in the very high magnification microlensing event MOA 2002-BLG-33. A 15 hour deviation from the light curve profile expected for a...
Alcock, C., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., Clement, C. M., ...
Fourier coefficents have been derived for the $V$ and $R$ light curves of 785 overtone RR Lyrae variables in 16 MACHO fields near the bar of the LMC. The $\phi_{31}$ and $R_{21}$ coefficients have...
Alcock, C., Alves, D. R., Becker, A., Bennett, D., Cook, K. H., Drake, A., ...
We have frequency analyzed 6391 variables classified earlier as fundamental mode RR Lyrae (RR0) stars in the MACHO database on the Large Magellanic Cloud (LMC). The overwhelming majority of these...
Djehuty, a Code for Modeling Stars in Three Dimensions (2003)
Bazan, G., Dearborn, D. S. P., Dossa, D. D., Eggleton, P. P., Taylor, A., Castor, J. I., ...
Current practice in stellar evolution is to employ one-dimensional calculations that quantitatively apply only to a minority of the observed stars (single non-rotating stars, or well detached...
Recent Microlensing Results from the MACHO Project (2003)
Popowski, P., Nelson, C. A., Bennett, D. P., Drake, A. J., Vandehei, T., Griest, K., ...
We describe a few recent microlensing results from the MACHO Collaboration. The aim of the MACHO Project was the identification and quantitative description of dark and luminous matter in the Milky...
A Search for Stellar Obscuration Events due to Dark Clouds (2003)
The recent detections of a large population of faint submillimetre sources, an excess halo gamma-ray background, and the extreme scattering events observed for extragalactic radio sources have been...
Variability-selected quasars in MACHO project Magellanic Cloud fields (2003)
Geha, M., Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., ...
We present 47 spectroscopically confirmed quasars discovered behind the Magellanic Clouds identified via photometric variability in the MACHO database. Thirty-eight quasars lie behind the Large...
Variability-Selected Quasars in MACHO Project Magellanic Cloud Fields (2002)
Geha, M., Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., ...
We present 47 spectroscopically-confirmed quasars discovered behind the Magellanic Clouds identified via photometric variability in the MACHO database. Thirty-eight quasars lie behind the Large...
Cavallo, R. M., Cook, K. H., Minniti, D., Vandehei, T.
We present an abundance analysis of six main sequence turnoff, subgiant, and giant branch stars toward the Galactic bulge that were observed with Keck/HIRES during microlensing events. This is an...
Blue Variable Stars from the MACHO database I: Photometry and Spectroscopy of the LMC sample (2002)
Keller, Stefan C., Bessell, M. S., Cook, K. H., Geha, M., Syphers, D.
We present the photometric properties of 1279 blue variable stars within the LMC. Photometry is derived from the MACHO database. The lightcurves of the sample exhibit a variety of quasi-periodic and...
MACHO Project Analysis of the Galactic Bulge Microlensing Events with Clump Giants as Sources (2002)
Popowski, P., Vandehei, T., Griest, K., Alcock, C., Allsman, R. A., Alves, D. R., ...
We present preliminary results of the analysis of 5 years of MACHO data on the Galactic bulge microlensing events with clump giants as sources. This class of events allows one to obtain robust...
Alcock, C., Allsman, R. A., Alves, D. R., Becker, A. C., Bennett, D. P., Cook, K. H., ...
We present a method for solving the lightcurve of an eclipsing binary system which contains a Cepheid variable as one of its components as well as the solutions for three eclipsing Cepheids in the...
Gravitational microlensing events due to stellar-mass black holes (2002)
Bennett, D. P., Becker, A. C., Quinn, J. L., Tomaney, A. B., Alcock, C., Allsman, R. A., ...
We present an analysis of the longest timescale microlensing events discovered by the MACHO Collaboration during a 7 year survey of the Galactic bulge. We find six events that exhibit very strong...
Alcock, C., Allsman, R. A., Alves, D. R., Becker, A. C., Bennett, D. P., Cook, K. H., ...
We present a method for solving the light curve of an eclipsing binary system that contains a Cepheid variable as one of its components as well as the solutions for three eclipsing Cepheids in the...
Gravitational Microlensing Events Due to Stellar Mass Black Holes (2001)
Bennett, D. P., Becker, A. C., Quinn, J. L., Tomaney, A. B., Alcock, C., Allsman, R. A., ...
We present an analysis of the longest timescale microlensing events discovered by the MACHO Collaboration during a 7 year survey of the Galactic bulge. We find 6 events that exhibit very strong...
The MACHO Project LMC Variable Star Inventory: X. The R Coronae Borealis Stars (2001)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A., Bennett, D. P., ...
We report the discovery of eight new R Coronae Borealis (RCB) stars in the Large Magellanic Cloud (LMC) using the MACHO project photometry database. The discovery of these new stars increases the...
MACHO 96-LMC-2: Lensing of a Binary Source in the LMC and Constraints on the Lensing Object (2000)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
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...
MACHO Project Limits on Black Hole Dark Matter in the 1-30 Solar Mass Range (2000)
Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We report on a search for long duration microlensing events towards the Large Magellanic Cloud. We find none, and therefore put limits on the contribution of high mass objects to the Galactic dark...
A 421 d Activity Cycle in the BeX Recurrent Transient A0538-66 from MACHO monitoring (2000)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We present a ~ 5-yr optical light curve of the recurrent Be/X-ray transient A0538-66 obtained as a by-product of the MACHO Project. These data reveal both a long-term modulation at P = 420.8 +/- 0.8...
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We attempt to determine whether the MACHO microlensing source stars are drawn from the average population of the LMC or from a population behind the LMC by examining the HST color-magnitude diagram...
Galactic Bulge Microlensing Events with Clump Giants as Sources (2000)
Popowski, P., Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., ...
We present preliminary results of the analysis of 5 years of MACHO data on the Galactic bulge microlensing events with clump giants as sources. In particular, we discuss: 1) the selection of `giant'...
Alcock, C., Allsman, R., Alves, D. R., Axelrod, T., Becker, A., Bennett, D., ...
More than 1300 variables classified provisionally as first overtone RR Lyrae pulsators in the MACHO variable star database of the Large Magellanic Cloud (LMC) have been subjected to standard...
The MACHO Project: Microlensing Detection Efficiency (2000)
Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
The MACHO project is a search for dark matter in the form of massive compact halo objects (MACHOs). The project has photometrically monitored tens of millions of stars in the Large Magellanic Cloud...
Searching for periodicities in the MACHO light curve of LMC X-2 (2000)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
Using the exceptional long-term monitoring capabilities of the MACHO project, we present here the optical history of LMC X-2 for a continuous 6-yr period. These data were used to investigate the...
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We present the microlensing optical depth towards the Galactic bulge based on the detection of 99 events found in our Difference Image Analysis (DIA) survey. This analysis encompasses three years of...
The MACHO Project 9 Million Star Color-Magnitude Diagram of the Large Magellanic Cloud (2000)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Basu, A., Becker, A. C., ...
We present a 9 million star color-magnitude diagram (9M CMD) of the LMC bar. The 9M CMD reveals a complex superposition of different age and metallicity stellar populations, with important stellar...
The MACHO Project: Microlensing Results from 5.7 Years of LMC Observations (2000)
Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We report on our search for microlensing towards the Large Magellanic Cloud (LMC). Analysis of 5.7 years of photometry on 11.9 million stars in the LMC reveals 13 - 17 microlensing events. This is...
Searching for periodicities in the MACHO light curve of LMC X-2 (2000)
Alcock, C., Allsman, R.A., Alves, D.R., Axelrod, T.S., Becker, A.C., Bennet, D.P., ...
The Distance to the LMC via the Eclipsing Binary HV 2274 (1999)
Nelson, C. A., Cook, K. H., Popowski, P., Alves, D. A.
We present UBV photometry of the eclipsing binary Harvard Variable 2274 in the Large Magellanic Cloud (LMC). The stellar parameters of this binary system were calculated by Guinan et al. (1998a) who...
Calibration of the MACHO Photometry Database (1999)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
The MACHO Project is a microlensing survey that monitors the brightnesses of 60 million stars in the Large Magellanic Cloud (LMC), Small Magellanic Cloud, and Galactic bulge. Our database presently...
EROS and MACHO Combined Limits on Planetary Mass Dark Matter in the Galactic Halo (1999)
Alcock, C., Allsman, R.A., Alves, D., Ansari, R., Aubourg, E., Axelrod, T.S., ...
Difference Image Analysis of Galactic Microlensing II. Microlensing Events (1999)
Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
The MACHO collaboration has been carrying out Difference Image Analysis (DIA) since 1996 with the aim of increasing the sensitivity to the detection of gravitational microlensing. This is a...
Difference Image Analysis of Galactic Microlensing I. Data Analysis (1999)
Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
This is a preliminary report on the application of Difference Image Analysis (DIA) to galactic bulge images. The aim of this analysis is to increase the sensitivity to the detection of gravitational...
Cepheid Variables in the LMC and SMC (1999)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., ...
In this paper, we will review major new results regarding classical Cepheids, in the Large Magellanic Cloud (LMC) and Small Magellanic Cloud (SMC). Specifically, we discuss recent work regarding...
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We present an analysis of the period distribution of $\sim 1800$ Cepheids in the Large Magellanic Cloud, based on data obtained by the MACHO microlensing experiment and on a previous catalogue by...
Alves, D. R., Basu, A., Cook, K. H., Welch, D. L., Alcock, C., Marshall, S., ...
This paper has been withdrawn
Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A., Bennett, D. P., ...
MACHO Project photometry of 45 LMC FO/SO beat Cepheids which pulsate in the first and second overtone (FO and SOo, respectively) has been analysed to determine the lightcurve characteristics for the...
Alves, D. R., Becker, A., Bennett, D. P., Cook, K. H., Freeman, K. C., ...
Using the novel data set of the MACHO project, we show that three ``Blazhko Effect'' RR Lyrae stars show nearly-pure amplitude modulation of a single pulsation mode. This is strong observational...
Discovery and Characterization of a Caustic Crossing Microlensing Event in the SMC (1998)
Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We present photometric observations and analysis of the second microlensing event detected towards the Small Magellanic Cloud (SMC), MACHO Alert 98-SMC-1. This event was detected early enough to...
EROS and MACHO Combined Limits on Planetary Mass Dark Matter in the Galactic Halo (1998)
Alcock, C., Allsman, R.A., Alves, D., Ansari, R., Aubourg, E., Axelrod, T.S., ...
EROS and MACHO Combined Limits on Planetary Mass Dark Matter in the Galactic Halo (1998)
Alcock, C., Allsman, R.A., Alves, D., Ansari, R., Aubourg, E., Axelrod, T.S., ...
Detection of Lithium in a Main Sequence Bulge Star Using Keck I as a 15m Diameter Telescope (1997)
Minniti, D., Vandehei, T., Cook, K. H., Griest, K., Alcock, C.
The bulge contains the most chemically evolved old stellar population in the Milky Way. Thanks to microlensing, it is now possible to obtain high resolution echelle spectra of bulge stars near the...
Pulsating Variable Stars in the MACHO Bulge database: The Semiregular Variables (1997)
Minniti, D., Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A., ...
We review the pulsating stars contained in the top 24 fields of the MACHO bulge database, with special emphasis on the red semiregular stars. Based on period, amplitude and color cuts, we have...
Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We report the discovery of 20 1H/2H and 7 F/1H beat Cepheids in the SMC by the MACHO Project. We utilize the 20 1H/2H stars to determine lightcurve shape for the SMC second-overtone (2H) mode of...
First detection of a gravitational microlensing candidate towards the Small Magellanic Cloud (1997)
Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We report the first discovery of a gravitational microlensing candidate towards a new population of source stars, the Small Magellanic Cloud (SMC). The candidate event's light curve shows no...
Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A., Cook, K. H., ...
We report the discovery of RV Tauri stars in the Large Magellanic Cloud. In light and colour curve behaviour, the RV Tauri stars appear to be a direct extension of the type II Cepheids to longer...
Bulge delta Scuti Stars in the MACHO Database (1997)
Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A., Bennett, D. P., ...
We describe the search for delta Scuti stars in the MACHO database of bulge fields. Concentrating on a sample of high amplitude delta Scutis, we examine the light curves and pulsation modes. We also...
Is the LMC Microlensing Due to an Intervening Dwarf Galaxy? (1997)
Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A., Bennett, D. P., ...
The recent suggestion that the microlensing events observed towards the Large Magellanic Cloud are due to an intervening Sgr-like dwarf galaxy is examined. A search for foreground RR Lyrae in the...
The RR Lyrae Population of the Galactic Bulge from the MACHO Database (1997)
Allsman, R. A., Alves, D. R., Axelrod, T. S., Basu, A., Baskett, L., ...
Mean colors and magnitudes of RR Lyrae stars in 24 fields towards the Galactic bulge from the MACHO database are presented. Accurate mean reddenings are computed for these fields on the basis of the...
The Zero Point of Extinction Toward Baade's Window From RR Lyrae Stars (1997)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We measure the zero point of the Stanek (1996) extinction map by comparing the observed (V-K) colors of 20 RR Lyrae stars (type ab) found in the MACHO survey with their intrinsic (V-K)_0 colors as a...
Alcock, C., Allen, W. H., Allsman, R. A., Alves, D., Axelrod, T. S., Banks, T. S., ...
We present analysis of MACHO Alert 95-30, a dramatic gravitational microlensing event towards the Galactic bulge whose peak magnification departs significantly from the standard point-source...
Planetary Microlensing from the MACHO Project (1996)
Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A., ...
We present the lightcurves of two microlensing events from the MACHO Project data that are likely to be due to lenses with masses similar to Jupiter's mass. Although the MACHO Project survey data are...
Gravitational Microlensing Results from MACHO (1996)
Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A. C., ...
The MACHO project is searching for dark matter in the form of massive compact halo objects (Machos), by monitoring the brightness of millions of stars in the Magellanic Clouds to search for...
Cepheids in the LMC: Results from the MACHO Project (1996)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A., ...
The approximately 1500 Cepheid variables in 22 LMC fields of the MACHO Project survey have been calibrated and analysed. In this paper, we report improved period ratios for a total of 73 beat...
RR Lyrae Stars in the MACHO Database (1996)
Alcock, C., Alves, D. R., Allsman, R. A., Axelrod, T. S., Becker, A., ...
The MACHO Project has catalogued $\sim 8000$ RR Lyrae stars in the Large Magellanic Cloud, $\sim 1800$ in the Galactic bulge, and $\sim$ 50 in the Sgr dwarf galaxy. These variables are excellent...
Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
We report the discovery of 73 double-mode RR Lyrae (RRd) stars in fields near the bar of the LMC. The stars are detected among the MACHO database of short-period variables that currently contains...
Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A. C., Bennett, D. P., ...
The MACHO Project is a search for dark matter in the form of massive compact halo objects (Machos). Photometric monitoring of millions of stars in the Large Magellanic Cloud (LMC), Small Magellanic...
The MACHO Project 2nd Year LMC Microlensing Results and Dark Matter Implications (1996)
Pratt, M. R., Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A. C., ...
The MACHO Project is searching for galactic dark matter in the form of massive compact halo objects (Machos). Millions of stars in the Large Magellanic Cloud (LMC), Small Magellanic Cloud (SMC), and...
A Binary Lensing Event Toward the LMC: Observations and Dark Matter Implications (1996)
Bennett, D. P., Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A., ...
The MACHO collaboration has recently analyzed 2.1 years of photometric data for about 8.5 million stars in the Large Magellanic Cloud (LMC). This analysis has revealed 8 candidate microlensing events...
MACHO Project Photometry of RR Lyrae Stars in the Sgr Dwarf Galaxy (1996)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A., Bennett, D. P., ...
We report the discovery of 30 type a,b RR Lyrae (RRab) which are likely members of the Sagittarius (Sgr) dwarf galaxy. Accurate positions, periods, amplitudes and magnitudes are presented. Their...
Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A., Bennett, D. P., ...
The MACHO project has been monitoring about ten million stars in the Large Magellanic Cloud in the search for gravitational microlensing events caused by massive compact halo objects (Machos) in the...
The MACHO Project LMC Variable Star Inventory: III. New R Coronae Borealis Stars (1996)
Alcock, C., Allsman, R. A., Alves, D. R., Axelrod, T. S., Becker, A., Bennett, D. P., ...
We report the discovery of two new R Coronae Borealis (RCB) stars in the Large Magellanic Cloud (LMC) using the MACHO project photometry database. The identification of both stars has been confirmed...
The MACHO Project: 45 Candidate Microlensing Events from the First Year Galactic Bulge Data (1995)
Alcock, C., Allsman, R. A., Axelrod, T. S., Bennett, D. P., Cook, K. H., Freeman, K. C., ...
We report the detection of 45 candidate microlensing events in fields toward the Galactic bulge. These come from the analysis of 24 fields containing 12.6 million stars observed for 190 days in 1993....
The MACHO Project Dark Matter Search (1995)
Bennett, D. P., Alcock, C., Allsman, R. A., Axelrod, T. S., Cook, K. H., Freeman, K. C., ...
We provide a status report on our search for dark matter in our Galaxy in the form of massive compact halo objects (or Machos), using gravitational microlensing of background stars. This search uses...
The MACHO Data Pipeline (1995)
Axelrod, T. S., Allsman, R. A., Quinn, P. J., Bennett, D. P., Freeman, K. C., Peterson, B. A., ...
The MACHO experiment is searching for dark matter in the halo of the Galaxy by monitoring more than 20 million stars in the LMC and Galactic bulge for gravitational microlensing events. The hardware...
Real-time Detection of Gravitational Microlensing (1995)
Pratt, M. R., Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Becker, A., ...
Real-time detection of microlensing has moved from proof of concept in 1994 to a steady stream of events this year. Global dissemination of these events by the MACHO and OGLE collaborations has made...
First Observation of Parallax in a Gravitational Microlensing Event (1995)
Alcock, C., Allsman, R. A., Alves, D., Axelrod, T. S., Bennett, D. P., Cook, K. H., ...
We present the first detection of parallax effects in a gravitational microlensing event. Parallax in a gravitational microlensing event observed only from the Earth appears as a distortion of the...
Alcock, C., Allsman, R. A., Axelrod, T. S., Bennett, D. P., Cook, K. H., Freeman, K. C., ...
The MACHO collaboration reports on the analysis of our first year LMC data, 9.5 million light curves with an average of 235 observations each. Automated selection procedures give 3 events consistent...
MACHO COLLABORATION SEARCH FOR BARYONIC DARK MATTER VIA GRAVITATIONAL MICROLENSING (1995)
Griest, K., Alcock, C., Allsman, R. A., Axelrod, T. S., Bennett, D. P., Cook, K. H., ...
Results are presented from the MACHO collaboration gravitational microlensing search. The experiment and the nearly 50 microlensing events that have been detected are described. Limits on the...
Variable Stars in the MACHO Collaboration Database (1995)
Cook, K. H., Alcock, C., Allsman, R. A., Axelrod, T. S., Freeman, K. C., Peterson, B. A., ...
The MACHO Collaboration's search for baryonic dark matter via its gravitational microlensing signature has generated a massive database of time ordered photometry of millions of stars in the LMC and...
Cepheids in the Magellanic Clouds (1995)
Welch, D. L., Alcock, C., Bennett, D. P., Cook, K. H., Allsman, R. A., Axelrod, T. S., ...
In the past few years, the Magellanic Clouds have been the targets for several major variable star surveys. The results of these surveys are now becoming available and it is clear that a Renaissance...
EXPERIMENTAL LIMITS ON THE DARK MATTER HALO OF THE GALAXY FROM GRAVITATIONAL MICROLENSING. (1995)
Alcock, C., Allsman, R. A., Axelrod, T. S., Bennett, D. P., Cook, K. H., Freeman, K. C., ...
We have monitored 8.6 million stars in the Large Magellanic Cloud for 1.1 years and have found 3 events consistent with gravitational microlensing. We place strong constraints on the Galactic halo...
Application of Cubic Splines to the Spectral Analysis of Unequally Spaced Data (1994)
Akerlof, Carl W., Alcock, C., Allsman, R., Axelrod, T., Bennett, D. P., Cook, K. H., ...
http://deepblue.lib.umich.edu/bitstream/2027.42/58217/2/spline_vas.c
Bennett, D. P., Alcock, C., Allsman, R. A., Axelrod, T. S., Cook, K. H., Freeman, K. C., ...
We review recent gravitational microlensing results from the EROS, MACHO, and OGLE collaborations, and present some details of the very latest MACHO results toward the Galactic Bulge. The MACHO...
Alcock, C., Allsman, R. A., Axelrod, T. S., Bennett, D. P., Cook, K. H., Freeman, K. C., ...
We report the discovery of 45 beat Cepheids in the Large Magellanic Cloud (LMC) using the MACHO Project photometry database. The variables which are pulsating simultaneously in two radial modes are...
Theory of Exploring the Dark Halo with Microlensing 1: Power--Law Models (1994)
Alcock, C., Allsman, R. A., Axelrod, T. S., Bennett, D. P., Cook, K. H., Evans, N. W., ...
The detection of microlensing has opened the way for the development of new methods in galactic astronomy. This series of papers investigates what microlensing can teach us about the structure and...
Possible Gravitational Microlensing of a Star in the Large Magellanic Cloud (1993)
Alcock, C., Akerlof, C. W., Allsman, R. A., Axelrod, T. S., Bennett, D. P., Chan, S., ...
There is now abundant evidence for the presence of large quantities of unseen matter surrounding normal galaxies, including our own$^{1,2}$. The nature of this `dark matter' is unknown, except that...
The kinetics of thymine dimer excision in ultraviolet-irradiated human cells.
Ehmann, U K, Cook, K H, Friedberg, E C
We have investigated the kinetics of the loss of thymine dimers from the acid-insoluble fraction of several ultraviolet (UV)-irradiated cultured human cell lines. Our results show that UV fluences...
The kinetics of thymine dimer excision in ultraviolet-irradiated human cells.
Ehmann, U K, Cook, K H, Friedberg, E C
We have investigated the kinetics of the loss of thymine dimers from the acid-insoluble fraction of several ultraviolet (UV)-irradiated cultured human cell lines. Our results show that UV fluences...