Resolved Stars and Unresolved Light in NGC 1311
Abstract
The dwarf irregular galaxy NGC 1311 is part of an HST multiwavelength imaging campaign of nearby galaxies. We have obtained WFPC2/F300W and F814W, and NICMOS/F160W images of NGC 1311 as part of our Cy10 and 12 programs. We also use a WFPC2/F606W image, taken from the Archive. We present color-magnitude and color-color plots of the resolved stars from these images. The data reveal a strong blue Main Sequence/Supergiant population of resolved stars and compact young star clusters. We use our multiwavelength photometry and spectrophotometric evolution models to study the age and metallicity of, and extinction toward the young stellar population.
We also study the unresolved light using the pixel-mapping techniques discussed in Eskridge et al. (2003 ApJ 586 923). We use an adaptive mask to block out pixels significantly contaminated by light from the bright stellar population. This allows us to study the ensemble properties of the fainter unresolved stars. We present pixel color-magnitude and color-color diagrams, along with pixel color maps of the unresolved light in NGC 1311 from our HST data. The relatively broad wavelength coverage of our data (2900Å to 1.6 microns) give us leverage to help disentangle the degeneracies amongst age, metallicity, burst strength and extinction. This research is supported by NASA/STScI grants GO-9124* and GO-9892*.- Publication:
-
American Astronomical Society Meeting Abstracts
- Pub Date:
- December 2004
- Bibcode:
- 2004AAS...205.9316E