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The original analysis of the star formation history in the NICMOS Deep images of the NHDF is extended to the entire NHDF utilizing NICMOS and WFPC2 archival data. The roughly constant star formation rate from redshifts 1 to 6 found in this study is consistent with the original results. Star formation rates from this study, Lyman break galaxies and sub-mm observations are now in concordance The spike of star formation at redshift 2 due to 2 ULIRGs in the small Deep NICMOS field is smoothed out in the larger area results presented here. The larger source base of this study allows comparison with predictions from hierarchical galaxy formation models. In general the observation are consistent with the predictions. The observed luminosity functions at redshifts 1-6 are presented for future comparisons with theoretical galaxy evolution calculations. Mid and far infrared properties of the sources are also calculated and compared with observations. A candidate for the VLA source VLA 3651+1221 is discussed.
This paper presents the star formation history in the NICMOS Northern Deep HDF. It uses the techniques of photometric redshifts and extinctions to correct for extinction of the ultra-violet flux. It presents a new method for correcting for surface br
We use deep HST ACS/HRC observations of a field within M32 (F1) and an M31 background field (F2) to determine the star formation history (SFH) of M32 from its resolved stellar population. We find that 2-5Gyr old stars contribute som40%+/- 17% of M32s
We present deep, wide-field g and r photometry of the transition type dwarf galaxy Leo T, obtained with the blue arm of the Large Binocular Telescope. The data confirm the presence of both very young (<1 Gyr) as well as much older (>5 Gyr) stars. We
If we are to develop a comprehensive and predictive theory of galaxy formation and evolution, it is essential that we obtain an accurate assessment of how and when galaxies assemble their stellar populations, and how this assembly varies with environ
We have determined the distance and star formation history of the Local Group dwarf galaxy LGS 3 from deep Hubble Space Telescope WFPC2 observations. LGS 3 is intriguing because ground-based observations showed that, while its stellar population is d