The MACHO Project: Microlensing Results from 5.7 Years of Large Magellanic Cloud Observations

@article{Alcock2000TheMP,
  title={The MACHO Project: Microlensing Results from 5.7 Years of Large Magellanic Cloud Observations},
  author={The Macho collaboration C. Alcock and Robyn A. Allsman and David Randall Alves and Timothy S. Axelrod and Andrew Cameron Becker and David P. Bennett and K. H. Cook and Neal Krishnakant Dalal and Andrew J. Drake and Kenneth C. Freeman and Marla Geha and Kim Griest and Matthew J. Lehner and Simon L. Marshall and Dante Minniti and Cailin Anne Nelson and Bruce A. Peterson and Piotr Popowski and Mark Robin Pratt and Peter Quinn and Christopher W. Stubbs and William J. Sutherland and Austin Bede Tomaney and Thor Vandehei and D. L. Welch},
  journal={The Astrophysical Journal},
  year={2000},
  volume={542},
  pages={281-307}
}
We report on our search for microlensing toward the Large Magellanic Cloud (LMC). Analysis of 5.7 yr of photometry on 11.9 million stars in the LMC reveals 13-17 microlensing events. A detailed treatment of our detection efficiency shows that this is significantly more than the ~2-4 events expected from lensing by known stellar populations. The timescales () of the events range from 34 to 230 days. We estimate the microlensing optical depth toward the LMC from events with 2 < < 400 days to be… Expand
Limits on the Machos from EROS-2
We present the results of the EROS-2 search for microlensing of stars in the Magellanic Clouds. Such events could be caused by macho dark matter in the Milky Way halo. Unlike all previous studies ofExpand
The MACHO Project: Microlensing Detection Efficiency
The MACHO project is a search for dark matter in the form of massive compact halo objects (MACHOs). The project has photometrically monitored over forty million stars in the Large Magellanic CloudExpand
Large Magellanic Cloud self-lensing for OGLE-II microlensing observations
In the framework of microlensing searches towards the Large Magellanic Cloud (LMC), we discuss the results presented by the OGLE collaboration for their OGLE-II campaign (Wyrzykowski et al. 2009). WeExpand
Kinematic outliers in the Large Magellanic Cloud: constraints on star-star microlensing
Although a decade of microlensing searches towards the Large Magellanic Cloud (LMC) has detected 13 25 possible microlensing events, the nature and the location of the lenses, being either haloExpand
Constraining the location of microlensing objects towards the Large Magellanic Cloud through parallax measurement in EAGLE observations
We investigate the possibility of determining whether microlensing objects towards the Large Magellanic Cloud (LMC) are in a Galactic thick disc, or are in a Galactic halo, by using parallaxExpand
POINT-AGAPE pixel lensing survey of M31: Evidence for a MACHO contribution to galactic halos
The POINT-AGAPE collaboration is carrying out a search for gravitational microlensing toward M31 to reveal galactic dark matter in the form of MACHOs (Massive Astrophysical Compact Halo Objects) inExpand
Large Magellanic Cloud Microlensing Optical Depth with Imperfect Event Selection
I present a new analysis of the MACHO Project 5.7 yr Large Magellanic Cloud (LMC) microlensing data set that incorporates the effects of contamination of the microlensing event sample by variableExpand
Statistical interpretation of Large Magellanic Cloud microlensing candidates
After a decade of gravitational microlensing experiments, a dozen microlensing candidates in the direction of the stars of the Large Magellanic Cloud (LMC) have been detected by the EROS and MACHOExpand
The origin of the microlensing events observed towards the LMC and the stellar counterpart of the Magellanic stream
We introduce a novel theoretical model to explain the long-standing puzzle of the nature of the microlensing events reported towards the Large Magellanic Cloud (LMC) by the MACHO and OGLEExpand
The OGLE view of microlensing towards the Magellanic Clouds – I. A trickle of events in the OGLE‐II LMC data★
We present the results from the Optical Gravitational Lensing Experiment II (OGLE-II) survey (1996–2000) towards the Large Magellanic Cloud (LMC), which has the aim of detecting the microlensingExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 49 REFERENCES
The MACHO Project Large Magellanic Cloud Microlensing Results from the First Two Years and the Nature of the Galactic Dark Halo
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 MagellanicExpand
The MACHO project: limits on planetary mass dark matter in the galactic halo from gravitational microlensing
The MACHO project has been monitoring about 10 million stars in the Large Magellanic Cloud (LMC) in the search for gravitational microlensing events caused by massive compact halo objects (MACHOs) inExpand
The macho project first-year large magellanic cloud results: The microlensing rate and the nature of the galactic dark halo
Since July 1992, the MACHO project has been carrying out long-term photometric monitoring of over 20 million stars in the Magellanic Clouds and Galactic bulge. Our aim is to search for the very rareExpand
A Caustic View of Halo Microlensing
The only microlensing events toward the Magellanic Clouds for which the location of the lens is strongly constrained are the two binary caustic crossing events. In at least one and possibly bothExpand
Discovery and characterization of a caustic crossing microlensing event in the small Magellanic cloud
We present photometric observations and analysis of the second microlensing event detected toward the Small Magellanic Cloud (SMC), MACHO Alert 98-SMC-1. This event was detected early enough to allowExpand
Can EROS and MACHO be detecting the galactic spheroid instead of the galactic halo?
TLDR
It is shown that, although the rate of events is lower than predicted by a galactic halo made of microlensing objects, it is still significant for EROS/MACHO observations and, because of the different matter distributions in the halo and spheroid components, future measurements ofmicrolensing in the galactic bulge and in M31 can provide information about the amounts of dark objects in the different galactic components. Expand
Theory of exploring the dark halo with microlensing. 1: Power law models
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 andExpand
Galactic microlensing as a method of detecting massive compact halo objects
The dark matter of the Galaxy may well consist of Jupiters, brown dwarfs, or the remnants of an early generation of stars. In 1986, Paczynski suggested that a population of such objects could beExpand
Calibration of the MACHO Photometry Database
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 presentlyExpand
Self-lensing Models of the Large Magellanic Cloud
All of the proposed explanations for the microlensing events observed toward the LMC have diffi- culties. One of these proposed explanations, LMC self-lensing, which invokes ordinary LMC stars as theExpand
...
1
2
3
4
5
...