Spectroscopy of NGC 4258 globular cluster candidates: membership
  confirmation and kinematics
  We present multi-object spectroscopic observations of 23 globular cluster
candidates (GCCs) in the prototypical megamaser galaxy NGC 4258, carried out
with the OSIRIS instrument at the 10.4 m Gran Telescopio Canarias. The
candidates have been selected based on the ($u^*\ -\ i^\prime$) versus
($i^\prime\ -\ K_s$) diagram, in the first application of the uiks-method to a
spiral galaxy. In the spectroscopy presented here, 70% of the candidates are
confirmed as globular clusters. Our results validate the efficiency of the
uiks-method in the sparser GC systems of spirals, and given the downward
correction to the total number of GCs, the agreement of the galaxy with the
correlations between black hole mass, and total number and mass of GCs is
actually improved. We find that the GCs, mostly metal-poor, co-rotate with the
HI disk, even at large galactocentric distances.
