Gravitational microlensing results from MACHO
The MACHO project is searching for dark qter inthe form of massive compact haio objects (Machos), by monitoring the brightness of millions of stars in the Magellanic Clouds to search for gravitational microlensing events. Analysis of our 1st 2.3 years of data for 8.5 million stars in the LMC yields 8 candidate microlensing events, well in excess of the {approx} 1 event expected from lensing by known low-mass stars. The event timescales range from 34 to 145 days, and the estimated optical depth is N 2x10{sup -7}, about half of that expected from a `standard` halo. Likelihood analysis indicates the typical lens mass is 0.5{sup +0.3}{sub -0.2}M{sub {circle_dot}}, suggesting they may be old white dwarfs.
- Research Organization:
- Lawrence Livermore National Lab., CA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States); National Science Foundation, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 588546
- Report Number(s):
- UCRL-JC--127202; CONF-9609179--; ON: DE98050236; CNN: NSF grant AST-8809616
- Country of Publication:
- United States
- Language:
- English
Similar Records
The MACHO Project Large Magellanic Cloud microlensing results from the first two years and the nature of the galactic dark halo
The MACHO project: Limits on planetary mass dark matter in the galactic halo from gravitational microlensing