The first data from the MACHO experiment
- Lawrence Livermore National Lab., CA (United States)
- California Univ., Berkeley, CA (United States). Center for Particle Astrophysics
- Australian National Univ., Canberra, ACT (Australia). Mount Stromlo and Siding Spring Observatories
MAssive Compact Halo Objects such as brown dwarfs, Jupiters, and black holes are prime candidates to comprise the dark halo of our galaxy. Paczynski noted that objects (dubbed MACHOS) with masses in the range 10{sup {minus}6} M{circle_dot} < M {approx_lt} 100M{circle_dot} can be detected via gravitational microlensing of stars in the Magellanic Clouds with the caveat that only about one in 10{sup 6} stars will be lensed at any given time. Our group has recently begun a search for microlensing using a refurbished 1.27 meter telescope at the Mount Stromlo Observatory in Australia. Since the summer of 1992, we have been imaging up to 10{sup 7} stars a night in the Large Magellanic Cloud using our large format two-color 3.4 {times} 10{sup 7} pixel CCD camera. Here I report on our first results based on an analysis of {approximately}10{sup 6} of these stars. Although this is not enough data to make definitive statements about the nature of the dark matter, we are able to conclude that the rate of variable star background events is not larger than the expected MACHO signal.
- Research Organization:
- Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States); California Univ., Berkeley, CA (United States)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 10162114
- Report Number(s):
- UCRL-JC-113606; CONF-921266-2; ON: DE93014423
- Resource Relation:
- Conference: Texas/PASCO `92 international conference,Berkeley, CA (United States),13-18 Dec 1992; Other Information: PBD: 17 Mar 1993
- Country of Publication:
- United States
- Language:
- English
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