162 citations · 799 across the 13 of their papers we have counts for
7 papers · 1 filter
A Deep HST Study of the Globular Cluster NGC 6397: Reduction Methods
Jay Anderson, Ivan R. King, Harvey B. Richer +6
We describe here the reduction methods that we developed to study the faintest red dwarfs and white dwarfs in an outer field of NGC6397, which was observed by \hst for 126 orbits i…
HST Photometry for the Halo Stars in the Leo Elliptical NGC 3377
W. E. Harris, G. L. H. Harris, A. C. Layden +1
We have used the ACS camera on HST to obtain (V,I) photometry for 57,000 red-giant stars in the halo of the Leo elliptical NGC 3377. We use this sample of stars to derive the metal…
The Discovery of Cepheids and a Distance to NGC 5128
Laura Ferrarese, Jeremy R. Mould, Peter B. Stetson +3
We discuss a new distance to NGC 5128 (Centaurus A) based on Cepheid variables observed with the Hubble Space Telescope. Twelve F555W (V) and six F814W (I) epochs of cosmic-ray-spl…
A Cepheid Distance to NGC 4603 in Centaurus
Jeffrey A. Newman, Stephen E. Zepf, Marc Davis +5
In an attempt to use Cepheid variables to determine the distance to the Centaurus cluster, we have obtained images of NGC 4603 with the Hubble Space Telescope on 9 epochs using WFP…
Discovery and Characterization of a Caustic Crossing Microlensing Event in the SMC
C. Alcock, R. A. Allsman, D. Alves +21
We present photometric observations and analysis of the second microlensing event detected towards the Small Magellanic Cloud (SMC), MACHO Alert 98-SMC-1. This event was detected e…
MACHO Alert 95-30 : First Real-Time Observation of Extended Source Effects in Gravitational Microlensing
C. Alcock, W. H. Allen, R. A. Allsman +54
We present analysis of MACHO Alert 95-30, a dramatic gravitational microlensing event towards the Galactic bulge whose peak magnification departs significantly from the standard po…