| |
|
|
|
|
(1995) Bottema, Roelof
Looking up, at night, one can immediately notice that the universe is almost empty. On a bright night, at first glance, a few nearby bright stars are visible. It is only after ones eyes are accustomed to the dark that the milky way becomes apparent as a hazy whitish band across the sky. External galaxies are equally faint and considerable effort is needed to study such objects. Kinematical studies of galaxies are most often carried out by gathering information of emission lines of the gaseous component. Most of the emisssion is then concentrated in a few discrete and bright lines for instance
Ha or the 21 cm neutral hydrogen line. The gas is a good tracer of the potential but constitutes only a minor fraction of the mass content of a galaxy. Therefore a study of
the stellar component, making up the dominant mass contribution in the inner regions, is warranted. In fact, the stellar velocity dispersion is a direct indicator of the local
mass density. ...
Zie Outline
Gebruik a.u.b. deze link om te verwijzen naar dit
document:
http://irs.ub.rug.nl/ppn/141668229 |
Meer informatie in de catalogus
Meer informatie in Picarta
|
|
| |
| To top
|
| |
© 2003-2007 RUG : De Rijksuniversiteit Groningen heeft de rechten van deze repository. Alle rechten voorbehouden. Powered by WildFire
| |