Search Publications
Hubble Space Telescope Observations of Nine High-Redshift ESSENCE Supernovae1,
Filippenko, Alexei V.; Wood-Vasey, W. Michael; Foley, Ryan J. +29 more
We present broadband light curves of nine supernovae ranging in redshift from 0.5 to 0.8. The supernovae were discovered as part of the ESSENCE project, and the light curves are a combination of Cerro Tololo 4 m and Hubble Space Telescope (HST) photometry. On the basis of spectra and/or light-curve fitting, eight of these objects are definitely Ty…
Stellar Cluster Fiducial Sequences with the Advanced Camera for Surveys
Ferguson, Henry C.; Brown, Thomas M.; Rich, R. Michael +6 more
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 F606W (broad V) and F814W (I) bands with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. These clusters are part of two large ACS programs meas…
Hubble Space Telescope ACS Images of the GG Tauri Circumbinary Disk
Stapelfeldt, K. R.; Ford, H. C.; Illingworth, G. D. +6 more
Hubble Space Telescope Advanced Camera for Surveys images of the young binary GG Tauri and its circumbinary disk in V and I bandpasses were obtained in 2002 and are the most detailed of this system to date. They confirm features previously seen in the disk including a ``gap'' apparently caused by shadowing from circumstellar material, an asymmetri…
The Dwarf Spheroidal Companions to M31: Variable Stars in Andromeda I and Andromeda III
Da Costa, G. S.; Pritzl, Barton J.; Armandroff, Taft E. +1 more
We present the results of variable star searches of the M31 dwarf spheroidal (dSph) companions Andromeda I and Andromeda III using the Hubble Space Telescope. A total of 100 variable stars were found in And I, while 56 were found in And III. One variable found in And I and another in And III may be type II Cepheids. In addition to this variable in…
Stellar Winds and Embedded Star Formation in the Galactic Center Quintuplet and Arches Clusters: Multifrequency Radio Observations
Johnson, Kelsey E.; Rodríguez, Luis F.; Goss, W. M. +1 more
A multifrequency, multiconfiguration study has been made of the compact radio sources in the Galactic center Quintuplet and Arches stellar clusters using the Very Large Array. Ten radio sources have been detected in the Quintuplet cluster. The majority of these radio sources have rising spectral indices and are positionally coincident with young m…
Determining the Physical Properties of the B Stars. II. Calibration of Synthetic Photometry
Fitzpatrick, E. L.; Massa, D.
We present a new calibration of optical (UBV, Strömgren uvbyβ, and Geneva) and near-IR (Johnson RIJHK and Two Micron All Sky Survey) photometry for B and early A stars derived from Kurucz ATLAS9 model atmospheres. Our sample of stars consists of 45 normal nearby B and early A stars that have high-quality, low-resolution IUE spectra and accurate Hi…
Elemental Abundances in Two High Column Density Damped Lyα Systems at z < 1.5
Rao, Sandhya M.; Howk, J. Christopher; Wolfe, Arthur M. +1 more
We present Keck HIRES abundance measurements and metal-line kinematic profiles of the damped Lyα systems (DLAs) toward the quasars Q0933+733 (zabs=1.479) and Q0948+433 (zabs=1.233). These two DLAs have among the five highest H I column densities at any redshift: N(HI)=4.2×1021 cm-2. The metal-line data, …
Probing the Kinematics of the Narrow-Line Region in Seyfert Galaxies with Slitless Spectroscopy: Observational Results
Gull, T. R.; Kraemer, S. B.; Crenshaw, D. M. +5 more
We present slitless spectra of 10 Seyfert galaxies observed with the Space Telescope Imaging Spectrograph on the Hubble Space Telescope (HST). The spectra cover the [O III] λλ4959, 5007 emission lines at a spectral resolving power of λ/Δλ~9000 and a spatial resolution of ~0.1". We compare the slitless spectra with previous HST narrowband images to…
Properties of Resolved Star Clusters in M51
Whitmore, Bradley C.; Chandar, Rupali; Lee, Myung Gyoon
We present a study of compact star clusters in the nearby pair of interacting galaxies NGC 5194/5195 (M51), based on multifilter Hubble Space Telescope (HST) WFPC2 archival images. We have detected ~400 isolated, resolved clusters in five HST WFPC2 fields of the two-galaxy system. Due to our requirement that the clusters be detected based only on …
A Possible Third Component in the L Dwarf Binary System DENIS-P J020529.0-115925 Discovered with the Hubble Space Telescope
Martín, E. L.; Bouy, H.; Bouvier, J. +1 more
We present results showing that the multiple system DENIS-P J020529.0-115925 is likely to be a triple system of very low mass stars and brown dwarfs. The secondary of this previously known binary system shows a clear elongation on six images obtained at six different epochs. Significant residuals remain after point-spread function (PSF) subtractio…