| EROS and MACHO Combined Limits on Planetary Mass Dark Matter in the Galactic Halo (2007) | |||||||||||||
Abstract | |||||||||||||
| The EROS and MACHO collaborations have each published upper limits on the amount of planetary mass dark matter in the Galactic Halo obtained from gravitational microlensing searches. In this paper the two limits are combined to give a much stronger constraint on the abundance of low mass MACHOs. Specifically, objects with masses 10 \Gamma7 M fi ! ¸ m ! ¸ 10 \Gamma3 M fi make up less than 25% of the halo dark matter for most models considered, and less than 10% of a standard spherical halo is made of MACHOs in the 3:5 \Theta 10 \Gamma7 M fi ! m ! 4:5 \Theta 10 \Gamma5 M fi mass range. Subject headings: dark matter - gravitational lensing - Stars: low-mass, brown dwarfs -- 3 -- If a significant fraction of the dark matter in the Galactic Halo is in the form of MACHOs (objects of masses m ? ¸ 10 \Gamma8 M fi ), then these objects can be detected via gravitational microlensing (Paczy'nski 1986), which is the temporary brightening of a background star as the unseen object... | |||||||||||||
Publication details | |||||||||||||
| |||||||||||||