Astronomy and Astrophysics – Astrophysics
Scientific paper
2000-10-18
Astronomy and Astrophysics
Astrophysics
To appear in the January 2001 issue of the PASP. 35 pages including 13 embedded postscript figures (one page each) and 4 embed
Scientific paper
10.1086/317974
We present deep Hubble Space Telescope optical imaging observations of two Galactic globular clusters, 47 Tuc and M15, using the Space Telescope Imaging Spectrograph (STIS) longpass (LP) filter and the Wide Field and Planetary Camera 2 (WFPC2) F606W and F814W filters. These globular clusters have very different metallicities ([Fe/H] = -0.7 dex for 47 Tuc, and [Fe/H] = -2.2 dex for M15), essentially spanning the metallicity distribution of the entire Milky Way globular cluster system, and were chosen to investigate the relationship between magnitudes in the non-standard STIS LP system and the better characterized WFPC2 magnitudes. We determine this relationship by combining our new STIS data with archival WFPC2 data, taking care to provide a robust and reliable transformation. Examining the 47 Tuc and M15 data separately, there is no evidence for a metallicity dependence in the transformation relations. This allows us to combine the data for both clusters, and also include the stars in the Small Magellanic Cloud that lie within the field of view of the 47 Tuc images, to determine final transformations that are valid for main sequence stars with colors in the range 0.3 < V606-I814 < 1.8. These final relations predict STIS magnitudes within 0.05 mag (1 sigma) of those measured for stars in both clusters. In an appendix, we discuss the differences between our empirical transformation relations and those predicted by synthetic photometry.
Gilmore Gerard
Houdashelt Mark L.
~Wyse Rosemary F. G.
No associations
LandOfFree
HST Color-Magnitude Data for Globular Clusters: I. Transformations Between STIS LP Magnitudes and WFPC2 F606W and F814W Magnitudes does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with HST Color-Magnitude Data for Globular Clusters: I. Transformations Between STIS LP Magnitudes and WFPC2 F606W and F814W Magnitudes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and HST Color-Magnitude Data for Globular Clusters: I. Transformations Between STIS LP Magnitudes and WFPC2 F606W and F814W Magnitudes will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-34348