Contents of: VI/111/./abstract/MVERHEIJ_TF_UMA.abs

The following document lists the file abstract/MVERHEIJ_TF_UMA.abs from catalogue VI/111.
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 In the process of trying to understand the Tully-Fisher
 relation, the relation between luminosity and rotation velocity
 of spiral galaxies, we have found for the Ursa Major cluster
 that the scatter around the relation decreases substantially
 when we introduce a second parameter, the IRAS flux at 60 micron.
 This might be very important, since it leads to a better
 understanding of how to use the Tully-Fisher relation when
 determining galaxy distances. Since distances from peculiar
 velocity measurements are very difficult to get, because the
 peculiar velocity of an individual galaxy is smaller than the
 uncertainty in the distance estimate, peculiar velocities might
 be subject to unknown systematic effects. Therefore it is
 important to understand the way the Tully-Fisher relation works.

 The aim of the proposal is to expand this preliminary result
 for Ursa Major. The cluster population resembles that of field
 galaxies while the small velocity dispersion allows to discriminate
 foreground and background galaxies. Its proximity enables us
 to obtain spatially resolved information for most of the individual
 galaxies. The Ursa Major cluster, which can be considered as a
 young cluster, is an excellent candidate to establish an improved
 Tully-Fisher relation. For this cluster we will increase
 the current IRAS-sample by a factor 2, and obtain much higher
 quality data.

 We have already obtained substantial datasets in the near-infrared
 and in neutral hydrogen, and together with the ISO data we will
 have a superior data set that will allow us to obtain a much
 better understanding of the Tully-Fisher relation than is
 currently available.