INVESTIGADORES
MOLLERACH Maria Silvia
artículos
Título:
Can EROS and MACHO be detecting the galactic spheroid instead of the galactic halo?
Autor/es:
GIUDICE, G. F.; MOLLERACH, S.; ROULET, E.
Revista:
PHYSICAL REVIEW D - PARTICLE AND FILDS
Editorial:
American Physical Society
Referencias:
Año: 1994 vol. 50 p. 2406 - 2413
ISSN:
0556-2821
Resumen:
Models of our Galaxy based on dynamical observations predict a spheroid
component much heavier than accounted for by direct measurements of star
counts and high velocity stars. If, as first suggested by Caldwell and
Ostriker, this discrepancy is due to a large population of faint
low-mass stars or dark objects in the spheroid, the spheroid could be
responsible for microlensing events for sources in the Large Magellanic
Cloud (LMC). We show that, although the rate of events is lower than
predicted by a galactic halo made of microlensing objects, it is still
significant for EROS andr MACHO observations. Because of the different
matter distributions in the halo and spheroid components, a comparison
between microlensing event rates in the LMC, future measurements of
microlensing in the galactic bulge and, possibly, in M31 can provide
information about the amount of dark objects in the different galactic
components. If the EROS and MACHO Collaborations find a deficiency with
respect to their halo expectation, when more statistics are available,
their detected events could be interpreted as coming from spheroid
microlenses, allowing for a galactic halo composed entirely of
nonbaryonic dark matter.