Ages

Globular Cluster Ages

A table of 43 V(TO-HB) globular cluster ages in Gyr with errors, for 10 different choices of the absolute magnitude of the HB (Mv(RR)). The various choices of Mv(RR) are at the head of each column. The first column is the theoretical Mv(RR) relation from Lee (1994). The second column is my best estimate for the correct Mv(RR) relation: Mv(RR) = 0.20[Fe/] + 0.98 and so gives my preferred age estimate. The other columns span the full range of recently determined Mv(RR) relations reported by various observers.
6
Mv(RR) Relation
0.17[Fe/H] + 0.79 0.20[Fe/H] + 0.98 0.15[Fe/H] + 0.98 0.15[Fe/H] + 0.725 0.20[Fe/H] + 1.06 0.20[Fe/H] + 0.82 0.25[Fe/H] + 1.14 0.25[Fe/H] + 0.915 0.30[Fe/H] + 1.22 0.30[Fe/H] + 1.01
Cluster Name
Age Err Age Err Age Err Age Err Age Err Age Err Age Err Age Err Age Err Age Err
N104 12.4 1.1 15.6 1.3 16.4 1.3 11.6 1.0 17.3 1.4 12.6 1.1 18.4 1.5 13.6 1.2 19.4 1.5 14.8 1.2
N288 16.5 1.3 19.4 1.6 20.9 1.7 15.8 1.3 21.1 1.7 16.2 1.3 21.4 1.7 16.7 1.3 21.7 1.7 17.3 1.4
N362 14.3 1.7 17.4 2.0 18.9 2.1 13.5 1.6 19.3 2.1 14.1 1.7 19.8 2.2 14.7 1.7 20.3 2.2 15.3 1.8
N1261 13.7 1.1 16.2 1.3 17.4 1.4 13.1 1.1 17.6 1.4 13.5 1.1 17.9 1.4 14.0 1.1 18.3 1.5 14.5 1.2
N1851 12.0 0.8 14.2 1.0 15.3 1.1 11.6 0.8 15.5 1.1 11.9 0.8 15.7 1.1 12.3 0.8 16.0 1.1 12.7 0.8
N1904 14.5 1.3 16.9 1.5 18.5 1.7 14.1 1.3 18.4 1.7 14.2 1.3 18.3 1.7 14.4 1.3 18.4 1.6 14.7 1.3
N2298 13.9 1.9 16.0 2.2 17.7 2.5 13.4 1.8 17.4 2.4 13.5 1.8 17.2 2.4 13.5 1.8 17.1 2.3 13.7 1.9
N2808 14.7 1.4 17.3 1.6 18.7 1.8 14.1 1.3 18.9 1.8 14.5 1.4 19.2 1.8 15.0 1.4 19.5 1.8 15.5 1.4
N3201 11.9 1.3 13.8 1.6 15.0 1.7 11.5 1.3 15.1 1.7 11.6 1.3 15.0 1.7 11.8 1.3 15.1 1.7 12.1 1.3
N4147 15.4 1.4 17.9 1.6 19.7 1.8 14.9 1.4 19.5 1.8 15.0 1.4 19.3 1.7 15.1 1.4 19.1 1.7 15.3 1.4
N4590 13.6 0.9 15.5 1.0 17.3 1.2 13.2 0.9 16.8 1.1 13.1 0.9 16.4 1.1 13.0 0.8 16.0 1.0 12.9 0.8
N5024 15.4 1.4 17.6 1.6 19.6 1.8 15.0 1.4 19.2 1.7 14.9 1.3 18.7 1.7 14.8 1.3 18.4 1.7 14.8 1.3
N5053 15.5 1.3 17.4 1.5 19.7 1.7 15.2 1.3 18.9 1.6 14.9 1.2 18.2 1.6 14.5 1.2 17.4 1.5 14.1 1.2
N5272 14.1 0.8 16.4 1.0 17.9 1.1 13.6 0.8 17.9 1.1 13.8 0.8 17.8 1.1 14.0 0.8 17.8 1.1 14.2 0.8
N5466 16.5 1.9 18.7 2.0 21.0 2.4 16.1 1.9 20.3 2.1 15.9 1.7 19.7 1.9 15.6 1.5 19.1 1.7 15.4 1.4
N5897 15.1 1.8 17.5 2.1 19.2 2.3 14.6 1.8 19.1 2.3 14.7 1.8 19.0 2.3 14.9 1.8 19.0 2.3 15.2 1.8
N5904 14.6 1.1 17.2 1.3 18.6 1.4 14.0 1.0 18.8 1.4 14.4 1.1 19.0 1.4 14.8 1.1 19.2 1.4 15.3 1.1
N6101 12.5 1.2 14.4 1.3 15.9 1.5 12.1 1.1 15.7 1.5 12.2 1.1 15.5 1.4 12.3 1.1 15.4 1.4 12.4 1.1
N6121 15.5 1.7 18.3 2.0 19.6 2.1 14.8 1.6 19.9 2.1 15.3 1.6 20.2 2.1 15.8 1.7 20.6 2.2 16.4 1.7
N6171 15.7 1.9 18.8 2.3 19.9 2.4 15.0 1.8 20.5 2.5 15.7 1.9 21.2 2.5 16.6 2.0 21.9 2.6 17.4 2.1
N6205 16.1 2.2 18.8 2.6 20.5 2.8 15.5 2.1 20.5 2.8 15.8 2.2 20.4 2.8 16.0 2.2 20.4 2.8 16.3 2.2
N6218 12.0 1.1 14.1 1.3 15.2 1.4 11.5 1.0 15.4 1.4 11.9 1.1 15.6 1.4 12.2 1.1 15.9 1.5 12.7 1.1
N6254 17.4 1.7 20.4 2.0 22.2 2.2 16.8 1.7 22.2 2.1 17.1 1.7 22.2 2.1 17.4 1.7 22.3 2.1 17.8 1.7
N6341 19.4 1.5 22.1 1.7 24.8 1.9 19.0 1.4 24.0 1.8 18.7 1.4 23.3 1.7 18.4 1.4 22.6 1.7 18.2 1.4
N6352 12.9 1.1 16.3 1.3 16.8 1.3 12.0 1.0 17.9 1.4 13.2 1.1 19.3 1.5 14.5 1.2 20.6 1.5 15.9 1.3
N6397 18.4 1.7 21.2 1.9 23.4 2.2 17.8 1.7 23.0 2.1 17.8 1.6 22.7 2.0 17.8 1.6 22.4 2.0 18.0 1.6
N6535 16.3 2.1 18.9 2.4 20.8 2.6 15.8 2.0 20.6 2.6 15.9 2.0 20.4 2.5 16.0 2.0 20.4 2.5 16.3 2.0
N6584 12.7 1.2 14.9 1.4 16.2 1.6 12.3 1.2 16.2 1.5 12.5 1.2 16.3 1.5 12.8 1.2 16.4 1.5 13.1 1.2
N6652 9.1 1.3 11.4 1.7 12.2 1.8 8.5 1.2 12.8 1.8 9.1 1.3 13.5 1.9 9.8 1.4 14.1 1.9 10.5 1.5
N6752 17.7 1.9 20.7 2.2 22.5 2.3 17.0 1.8 22.5 2.3 17.4 1.8 22.6 2.3 17.7 1.8 22.8 2.3 18.2 1.9
N6809 16.5 1.2 19.1 1.3 21.0 1.5 16.0 1.2 20.8 1.4 16.1 1.1 20.5 1.4 16.1 1.1 20.4 1.3 16.3 1.1
N6838 11.3 0.9 14.3 1.1 14.8 1.1 10.5 0.8 15.8 1.1 11.5 0.9 16.9 1.2 12.5 0.9 18.0 1.3 13.7 1.0
N7006 14.0 1.1 16.4 1.3 17.9 1.4 13.5 1.1 17.9 1.4 13.8 1.1 17.9 1.4 14.0 1.1 18.0 1.4 14.3 1.1
N7078 17.1 1.7 19.5 2.0 21.9 2.2 16.7 1.7 21.2 2.2 16.5 1.7 20.7 2.1 16.3 1.7 20.2 2.1 16.2 1.7
N7099 16.9 1.6 19.3 1.8 21.6 2.0 16.5 1.5 21.0 1.9 16.3 1.5 20.4 1.8 16.1 1.5 19.9 1.8 16.0 1.4
N7492 17.6 1.9 20.3 2.0 22.4 2.4 17.0 1.9 22.1 2.2 17.1 1.7 21.9 2.1 17.2 1.6 21.7 2.0 17.4 1.6
Ter 7 7.2 0.5 8.7 0.8 9.0 0.8 6.8 0.4 9.7 0.9 7.3 0.5 10.6 1.0 7.9 0.7 11.4 1.1 8.7 0.8
Ter 8 16.9 1.5 19.4 1.7 21.5 1.9 16.4 1.5 21.1 1.8 16.4 1.4 20.7 1.8 16.3 1.4 20.4 1.8 16.3 1.4
Rup 106 13.2 0.8 15.7 0.9 17.4 1.0 12.7 0.8 17.4 1.0 12.9 0.8 17.3 1.0 13.0 0.8 17.2 1.0 13.2 0.8
Pal 5 13.4 1.4 15.7 1.6 17.0 1.9 12.9 1.4 17.1 1.8 13.2 1.4 17.2 1.7 13.5 1.3 17.4 1.6 13.9 1.3
Pal 12 9.4 1.4 11.7 1.7 12.6 1.9 8.8 1.4 13.1 1.8 9.3 1.4 13.5 1.8 9.8 1.4 13.9 1.8 10.4 1.4
IC4499 10.6 1.1 12.2 1.2 13.4 1.4 10.3 1.0 13.3 1.3 10.4 1.0 13.1 1.3 10.4 1.0 13.1 1.3 10.6 1.0
Arp 2 12.3 0.8 14.2 1.0 15.6 1.1 11.9 0.8 15.5 1.1 12.0 0.8 15.4 1.0 12.1 0.8 15.4 1.0 12.4 0.8