The globular cluster systems of NGC 3258 and NGC 3268 in the Antlia cluster*
1
Universidad de Concepción, Departamento de Física, Casilla 160-C, Concepción, Chile
2
Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque S/N, 1900-La Plata, Argentina and CONICET
Corresponding author: B. Dirsch, bdirsch@cepheid.cfm.udec.cl
Received:
16
April
2003
Accepted:
30
June
2003
The Antlia galaxy cluster is the third nearest galaxy cluster after Virgo and
Fornax. We used the wide-field MOSAIC camera of the 4-m CTIO telescope to
search in the brightest
cluster galaxies for globular cluster systems, which were detected in the two
larger ellipticals – NGC 3258 and NGC 3268. These galaxies each contain
several thousand clusters; NGC 3258 more than NGC 3268. The color distributions
of the globular cluster systems are clearly bimodal. The peak colors agree with
those of other ellipticals. The radial number density profiles of
the globular cluster systems
are indistinguishable for the two galaxies and no difference in the
distribution of red and blue clusters – as observed in other elliptical galaxies –
can be seen.
The light profile of NGC 3268 appears to be similar to that of NGC 1399, the
central galaxy of the Fornax cluster. NGC 3258 has a light profile which is steeper
at large radii.
Both galaxies exhibit color gradients, becoming bluer outwards.
In NGC 3268, the color and morphology in the inner 3´´ indicate the
presence of an inner dusty disk.
The globular cluster systems closely trace the galaxy light in the studied radial
regime. The elongation of the cluster systems of both galaxies is approximately
aligned
at large radii with the connecting axis of the two galaxies.
We find specific frequencies within a radial range of 4´ of 
for NGC 3268 and
for NGC 3258.
As a byproduct resulting from surveying our wide-field frames, we describe a strange
absorption feature in the Antlia spiral galaxy NGC 3269, which we
argue might be a tiny galactic dust cloud projected onto NGC 3269.
Key words: galaxies: elliptical and lenticular, cD / galaxies: individual: NGC 3258, NGC 3268, NGC 3269 / galaxies: star clusters / galaxies: stellar content / galaxies: structure
© ESO, 2003