Calibration of the Faber-Jackson relation for M31 globular clusters
  using Hipparcos data
  In this paper we present a data analysis regarding globular clusters as
possible extragalactic distance indicators. For this purpose, we collected all
velocity dispersion measurements published for galactic and M31 globular
clusters. The slope and the zero-point of the Faber-Jackson relation were
calibrated using Hipparcos distance measurements, and the relation was applied
to extragalactic globular clusters in M31. A distance modulus of 24.12 \pm 0.45
mag was found. This is coherent with what is found by fitting the red giant
branches of globular clusters (24.47 \pm 0.07, Holland 98), and is found from
the peak of globular clusters luminosity function (24.03 \pm 0.23, Ostriker an
d Gnedin 97), but shorter than the 24.7 \pm 0.2 mag (Lanoix et al. 98) and
24.77 \pm 0.11 mag (Feast and Catchpole 97), obtained by using Hipparcos data
to calibrate the Cepheid period-luminosity. This calibrated Faber-Jackson
relation can now be directly use for other Sc galaxies with resolved globular
clusters, as soon as large amounts of spectra will become available, e.g.,
through the VLT.
