The Distance to the Galactic Globular Cluster, 47 Tuc
Abstract
We present a new distance determination to the Galactic globular cluster 47 Tucanae by fitting the spectral energy distributions of its white dwarfs to pure hydrogen atmosphere white dwarf models. Our photometric data set is obtained from a 121 orbit Hubble Space Telescope program using the Wide Field Camera 3 UVIS/IR channels, capturing F390W, F606W, F110W, and F160W images. These images cover more than 60 arcmin2 and extend over a radial range of 5-13.7 arcmin (6.5-17.9 pc) within the globular cluster. Here, we present our best fitting distance modulus using a likelihood analysis. We also search the white dwarf photometry for infrared excess in the F160W filter, indicative of protoplanetary disks or low mass companions, and find no convincing cases within our sample.
- Publication:
-
American Astronomical Society Meeting Abstracts #219
- Pub Date:
- January 2012
- Bibcode:
- 2012AAS...21921102W