Search Publications
The Frequency of Binary Stars in the Core of 47 Tucanae
Albrow, Michael D.; Sarajedini, Ata; Gilliland, Ronald L. +3 more
Differential time series photometry has been derived for 46,422 main-sequence stars in the core of 47 Tucanae. The observations consisted of near-continuous 160 s exposures alternating between the F555W and F814W filters for 8.3 days in 1999 July with the Wide Field Planetary Camera 2 on the Hubble Space Telescope. Using Fourier and other search m…
A Chandra X-Ray Study of NGC 1068. I. Observations of Extended Emission
Young, A. J.; Wilson, A. S.; Shopbell, P. L.
We report subarcsecond-resolution X-ray imaging spectroscopy of the archetypal type 2 Seyfert galaxy NGC 1068 with the Chandra X-Ray Observatory. The observations reveal the detailed structure and spectra of the 13 kpc extent nebulosity previously imaged at lower resolution with ROSAT. The Chandra image shows a bright, compact source coincident wi…
Near-Infrared Integral Field Spectroscopy and Mid-Infrared Spectroscopy of the Starburst Galaxy M82
Lutz, D.; Förster Schreiber, N. M.; Genzel, R. +2 more
We present new infrared observations of the central regions of the starburst galaxy M82. The observations consist of near-infrared integral field spectroscopy in the H and K bands obtained with the MPE 3D instrument and of λ=2.4-45 µm spectroscopy from the Short Wavelength Spectrometer (SWS) onboard the Infrared Space Observatory. These meas…
First Results from the Anglo-Australian Planet Search: A Brown Dwarf Candidate and a 51 Peg-like Planet
Butler, R. Paul; Vogt, Steven S.; Henry, Gregory W. +5 more
We report results from the Anglo-Australian Planet Search, a survey for planets around 200 solar-type stars in the southern hemisphere that is being carried out on the 3.9 m Anglo-Australian Telescope. Limiting Doppler precisions of 3 m s-1 have been demonstrated from the first 2.5 years of operation, making this the highest-precision planet searc…
Chandra Exposes the Core-collapsed Globular Cluster NGC 6397
Heinke, C. O.; Cool, A. M.; Grindlay, J. E. +2 more
We report results of the Chandra deep-imaging observation of the closest post-core-collapse globular cluster, NGC 6397. Some 25 sources are detected within 2' of the cluster center, of which ~20 are likely cluster members, with LX>~3×1029 ergs s-1. The X-ray spectra suggest identifications with one quiescent low…
Chandra Limits on X-Ray Emission Associated with the Supermassive Black Holes in Three Giant Elliptical Galaxies
Angelini, Lorella; Loewenstein, Michael; Mushotzky, Richard F. +2 more
Elliptical galaxy nuclei are the sites of the largest black holes known but typically show little or no nuclear activity. We investigate this extreme quiescence using Chandra X-Ray Observatory observations of the giant elliptical galaxies NGC 1399, NGC 4472, and NGC 4636. The unique Chandra imaging power enables us to place upper limits of 7.3, 15…
Dynamical Friction in DE Globular Cluster Systems
Ferguson, Henry C.; Mack, Jennifer; Stiavelli, Massimo +3 more
The dynamical friction timescale for globular clusters to sink to the center of a dwarf elliptical galaxy (dE) is significantly less than a Hubble time if the halos have King-model or isothermal profiles and the globular clusters formed with the same radial density profile as the underlying stellar population. We examine the summed radial distribu…
High-Resolution X-Ray and Ultraviolet Spectroscopy of the Complex Intrinsic Absorption in NGC 4051 with Chandra and the Hubble Space Telescope
Brandt, W. N.; Kaspi, Shai; Elvis, Martin +6 more
We present the results from simultaneous observations of the narrow-line Seyfert 1 galaxy NGC 4051 with the Chandra High Energy Transmission Grating Spectrometer and the Hubble Space Telescope Space Telescope Imaging Spectrograph. The X-ray grating spectrum reveals absorption and emission lines from hydrogen-like and helium-like ions of O, Ne, Mg,…
The Gaseous Extent of Galaxies and the Origin of Lyα Absorption Systems. V. Optical and Near-Infrared Photometry of Lyα-absorbing Galaxies at z<1
Chen, Hsiao-Wen; Lanzetta, Kenneth M.; Webb, John K. +1 more
We present results of a program to obtain and analyze HST WFPC2 images and ground-based images of galaxies identified in an imaging and spectroscopic survey of faint galaxies in fields of HST spectroscopic target QSOs. Considering a sample of physically correlated galaxy and absorber pairs with galaxy-absorber cross-correlation amplitude ξga<…
Evidence for a Supermassive Black Hole in the S0 Galaxy NGC 3245
Filippenko, Alexei V.; Ho, Luis C.; Rix, Hans-Walter +3 more
The S0 galaxy NGC 3245 contains a circumnuclear disk of ionized gas and dust with a radius of 1.1" (110 pc), making it an ideal target for dynamical studies with the Hubble Space Telescope (HST). We have obtained spectra of the nuclear disk with the Space Telescope Imaging Spectrograph, using a 0.2" wide slit at five parallel positions. Measuremen…