J/ApJS/73/671 M87 globular clusters BVI photometry (Couture+, 1990)
BVI photometry of globular clusters in M87
COUTURE J., HARRIS W.E., ALLWRIGHT J.W.B.
<Astrophys. J. Suppl. Ser. 73, 671 (1990)>
=1990ApJS...73..671C 1990ApJS...73..671C (SIMBAD/NED Reference)
ADC_Keywords: Clusters, globular; Photometry, CCD
Keywords: clusters: globular - galaxies: individual (M87) - stars: abundances
Abstract:
We present CCD photometry in B, V, and I for a sample of globular clusters
in the Virgo central giant elliptical galaxy M87. Our measured sample
comprises 270 objects brighter than V∼23.4mag and with distances r>25"
(>2kpc) from the center of the galaxy. In agreement with the recent study
of Cohen, we find no detectable gradient of mean cluster color (metallicity)
in (B-V) or (V-I) with radial distance. The cluster system does, however,
display a large dispersion in color at any radius, corresponding to
sigma([Fe/H])∼0.6 about a mean metallicity (Fe/H]≳-1.1 according to our
color index scale. The difference in mean color between the globular
clusters and the underlying halo light of the galaxy itself, found
previously by Strom and coworkers and by Cohen, shows up strongly in all
of our color indices; we find virtually no clusters as red as mean color
of the halo stars at any radius.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2 50 273 BVI photometry of M87 globular clusters
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Byte-by-byte Description of file: table2
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Bytes Format Units Label Explanations
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1- 3 I3 --- SeqNum Starlike sequential number
6- 10 F5.1 pix Xpos X position
13- 17 F5.1 pix Ypos Y position
20- 24 F5.1 arcsec Dist Distance
28- 32 F5.2 mag Vmag V magnitude
34- 38 F5.2 mag B-V (B-V) color
40- 44 F5.2 mag V-I (V-I) color
47- 50 I4 --- S6 []? Cross-identification with S6 catalog
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References:
Cohen J.G., 1988, A.J., 95, 682
Strom S.E. at al., 1981, Ap.J., 245, 416 (S6)
Historical Notes: Keypunched at CDS
(End) Marie-Jose Wagner, Patricia Bauer [CDS] 27-Feb-1995