papers

Publications (15)

astro-ph2008

The WFC3 Galactic Bulge Treasury Program: A First Look at Resolved Stellar Population Tools

Thomas M. Brown, Kailash Sahu, Manuela Zoccali +12

[Abridged] When WFC3 is installed on HST, the community will have powerful new tools for investigating resolved stellar populations. The WFC3 Galactic Bulge Treasury program will o…

astro-ph2003

Evidence for a Significant Intermediate-Age Population in the M31 Halo from Main Sequence Photometry

Thomas M. Brown, Henry C. Ferguson, Ed Smith +5

We present a color-magnitude diagram (CMD) for a minor-axis field in the halo of the Andromeda galaxy (M31), 51 arcmin (11 kpc) from the nucleus. These observations, taken with the…

astro-ph2006

The Detailed Star Formation History in the Spheroid, Outer Disk, and Tidal Stream of the Andromeda Galaxy

Thomas M. Brown, Ed Smith, Henry C. Ferguson +5

Using the Advanced Camera for Surveys on the Hubble Space Telescope, we have obtained deep optical images reaching stars well below the oldest main sequence turnoff in the spheroid…

astro-ph2005

Deep Photometry of Andromeda Reveals Striking Similarities in the Tidal Stream and Spheroid Populations

Thomas M. Brown, Ed Smith, Puragra Guhathakurta +5

We present a color-magnitude diagram (CMD) for a field in the giant tidal stream of the Andromeda galaxy (M31). These observations, taken with the Advanced Camera for Surveys on th…

astro-ph2008

The Dearth of UV-Bright Stars in M32: Implications for Stellar Evolution Theory

Thomas M. Brown, Ed Smith, Henry C. Ferguson +3

Using the Space Telescope Imaging Spectrograph on the Hubble Space Telescope, we have obtained deep far-ultraviolet images of the compact elliptical galaxy M32. When combined with…

astro-ph2007

The Extended Star Formation History of the Andromeda Spheroid at Twenty One Kiloparsecs on the Minor Axis

Thomas M. Brown, Ed Smith, Henry C. Ferguson +8

Using the HST ACS, we have obtained deep optical images of a southeast minor-axis field in the Andromeda Galaxy, 21 kpc from the nucleus. In both star counts and metallicity, this…

astro-ph2005

Stellar Cluster Fiducial Sequences with the Advanced Camera for Surveys

Thomas M. Brown, Henry C. Ferguson, Ed Smith +6

We present color-magnitude diagrams of five Galactic globular clusters and one Galactic open cluster spanning a wide range of metallicity (-2.1 < [Fe/H] < +0.3), as observed in the…

astro-ph.GA2010

The WFC3 Galactic Bulge Treasury Program: Metallicity Estimates for the Stellar Population and Exoplanet Hosts

Thomas M. Brown, Kailash Sahu, Jay Anderson +14

We present new UV-to-IR stellar photometry of four low-extinction windows in the Galactic bulge, obtained with the Wide Field Camera 3 on the Hubble Space Telescope (HST). Using ou…

astro-ph2003

Far-Ultraviolet Emission from Elliptical Galaxies at z=0.33

Thomas M. Brown, Henry C. Ferguson, Ed Smith +4

We present far-ultraviolet (far-UV) images of the rich galaxy cluster ZwCl1358.1+6245, taken with the Space Telescope Imaging Spectrograph on board the Hubble Space Telescope (HST)…

astro-ph2004

Age Constraints for an M31 Globular Cluster from Main Sequence Photometry

Thomas M. Brown, Henry C. Ferguson, Ed Smith +5

We present a color-magnitude diagram (CMD) of the globular cluster SKHB-312 in the Andromeda galaxy (M31), obtained with the Advanced Camera for Surveys on the Hubble Space Telesco…

astro-ph2008

The Extended Star Formation History of the Andromeda Spheroid at 35 Kpc on the Minor Axis

Thomas M. Brown, Rachael Beaton, Masashi Chiba +14

Using the HST ACS, we have obtained deep optical images reaching well below the oldest main sequence turnoff in fields on the southeast minor-axis of the Andromeda Galaxy, 35 kpc f…

astro-ph2004

RR Lyrae Stars in the Andromeda Halo from Deep Imaging with the Advanced Camera for Surveys

Thomas M. Brown, Henry C. Ferguson, Ed Smith +4

We present a complete census of RR Lyrae stars in a halo field of the Andromeda galaxy. These deep observations, taken as part of a program to measure the star formation history in…

astro-ph.SR2011

HST/ACS Observations of RR Lyrae Stars in Six Ultra-deep Fields of M31

Elizabeth J. Jeffery, Ed Smith, Thomas M. Brown +6

We present HST/ACS observations of RR Lyrae variable stars in six ultra deep fields of the Andromeda galaxy (M31), including parts of the halo, disk, and giant stellar stream. Past…

astro-ph.SR2010

The Blue Hook Populations of Massive Globular Clusters

Thomas M. Brown, Allen V. Sweigart, Thierry Lanz +3

We present new HST ultraviolet color-magnitude diagrams of 5 massive Galactic globular clusters: NGC 2419, NGC 6273, NGC 6715, NGC 6388, and NGC 6441. These observations were obtai…

astro-ph.CO2009

Deep Optical Photometry of Six Fields in the Andromeda Galaxy

Thomas M. Brown, Ed Smith, Henry C. Ferguson +7

Using the Advanced Camera for Surveys on the Hubble Space Telescope, we have obtained deep optical images reaching well below the oldest main sequence turnoff in six fields of the…