Star Clusters Flashcards
halo
spherically symmetric distribution of older stars - less dense the further out
disk
distribution of stars orbiting center on thin plane
bulge
spherical distribution surrounding center
galactic cluster (open cluster)
loose groupings of stars
globular cluster
dense, spherical gathering of stars
radial velocity
within line of sight
tangential velocity
on the plane of the sky
virial theorem
relation between U and KE that described when cluster comes into equilibrium
relaxation
star equilibrate due to gravitational encounters over time (rms velocity is the average velocity after relaxation)
relaxation time
time it takes for star to equilibrate
evaporation time
time which large # of stars leave cluster
white dwarfs
low L population
population I stars
rich in metals
population II
poor in metals
