Date:
Tue, 24/11/201512:30-13:30
Location:
Kaplun building, Room No. 200
Lecturer: Dr. Shigeki Inoue
Affiliation: Racah Institute of Physics,
The Hebrew University of Jerusalem
Abstract:
It is a classical problem in astronomy to
determine the local dark matter density (LDMD)
of the solar system. The DM density at the solar
radius can be estimated from the Galactic
rotation curve using a spherical assumption for
the dark matter halo. However, dark matter
haloes are generally aspherical, therefore the
DM density deduced from the rotation curve
can differ from the LDMD around the solar
system. In other words, the difference between
them can be used for deducing the shape of the
Galactic DM halo. Moreover, the determination
of the LDMD is relevant to direct/indirect DM
detection experiments and the essential
question of 'what is dark matter?' The LDMD
can be measured from vertical profiles of
density and velocity dispersion of solar-
neighborhood stars, and astrometric
observations provide indispensable data for the
LDMD determination: distances and proper
motions of the stars. However, current
determinations of the LDMD are significantly
discrepant by studies, and we have not seemed
to obtain a credible value of the LDMD. In this
study, I invent a method for mock observations
for determining the LDMD, and discuss what is
the observational precision required for an
accurate determination of the LDMD. Finally, I
will assess whether or not the new satellite,
Gaia, could determine the LDMD with accuracy.
Additional details of the upcoming Astrophysics'
seminars can be found on the following link.
האירוע הזה כולל שיחת וידאו ב-Google Hangouts.
הצטרף: https://hangouts.google.com/hangouts/_/mail.huji.ac.il/astrophysics?hceid=bWFpbC5odWppLmFjLmlsX2c0czhydDlpcmhwZzRvdGNybWIzZGFqcjdvQGdyb3VwLmNhbGVuZGFyLmdvb2dsZS5jb20.ubiirug743iietns7pc78565u8&hs=121