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A Census of Optical and Near-Infrared Selected Star-forming and Passively Evolving Galaxies at Redshift z ~ 2
Pettini, Max; Erb, Dawn K.; Shapley, Alice E. +3 more
Using the extensive multiwavelength data in the GOODS-North field, including our ground-based rest-frame UV spectroscopy and near-IR imaging, we construct and draw comparisons between samples of optical and near-IR selected star-forming and passively evolving galaxies at redshifts 1.4<~z<~2.6. We find overlap at the 70%-80% level in samples …
Measuring the Three-dimensional Structure of Galaxy Clusters. I. Application to a Sample of 25 Clusters
Sereno, Mauro; Bautz, Mark W.; Longo, Giuseppe +1 more
We discuss a method to constrain the intrinsic shapes of galaxy clusters by combining X-ray and Sunyaev-Zel'dovich observations. The method is applied to a sample of 25 X-ray-selected clusters, with measured Sunyaev-Zel'dovich temperature decrements. The sample turns out to be slightly biased, with strongly elongated clusters preferentially aligne…
The Physical Properties and Effective Temperature Scale of O-Type Stars as a Function of Metallicity. II. Analysis of 20 More Magellanic Cloud Stars and Results from the Complete Sample
Massey, Philip; Pauldrach, A. W. A.; Bresolin, Fabio +3 more
In order to determine the physical properties of the hottest and most luminous stars and understand how these properties change as a function of metallicity, we have analyzed HST/UV and high-S/N optical spectra of an additional 20 Magellanic Cloud stars, doubling the sample presented in the first paper in this series. Our analysis uses non-LTE lin…
Mass-to-Light Ratios of Field Early-Type Galaxies at z ~ 1 from Ultradeep Spectroscopy: Evidence for Mass-dependent Evolution
Rosati, P.; Rix, H. -W.; van der Wel, A. +3 more
We present an analysis of the fundamental plane for a sample of 27 field early-type galaxies in the redshift range 0.6<z<1.15 in the Chandra Deep Field-South and the field of the background cluster RDCS 1252.9-2927. Sixteen of the galaxies are at z>0.95. The galaxies in this sample have high signal-to-noise ratio spectra obtained at the V…
The Assembly of Diversity in the Morphologies and Stellar Populations of High-Redshift Galaxies
Papovich, Casey; Dickinson, Mark; Ferguson, Henry C. +2 more
We have used deep images from the Hubble Space Telescope to study the evolution in the morphologies, sizes, stellar masses, colors, and internal color dispersion of galaxies in the Hubble Deep Field-North. We selected two galaxy samples at 0.7<=z<=1.4 and 1.9<=z<=3.0 from a near-infrared, flux-limited catalog with complete photometric …
Galaxy Morphologies in the Hubble Ultra Deep Field: Dominance of Linear Structures at the Detection Limit
Elmegreen, Bruce G.; Elmegreen, Debra Meloy; Rubin, Douglas S. +1 more
Galaxies in the Hubble Ultra Deep Field (UDF) larger than 10 pixels (0.3") have been classified according to morphology, and their photometric properties are presented. There are 269 spiral, 100 elliptical, 114 chain, 126 double-clump, 97 tadpole, and 178 clump-cluster galaxies. We also cataloged 30 B-band and 13 V-band dropouts and calculated the…
How to Channel Photospheric Oscillations into the Corona
Erdélyi, R.; De Pontieu, B.; De Moortel, I.
There are now many observations of waves in the solar corona with periods around 5 minutes. The source of these waves is uncertain, although global p-modes in the photosphere are an obvious candidate, given the similarity of the dominant periods. However, p-modes are traditionally considered evanescent in the upper photosphere, and it has been unc…
Cepheid Calibrations from the Hubble Space Telescope of the Luminosity of Two Recent Type Ia Supernovae and a Redetermination of the Hubble Constant
Filippenko, Alexei V.; Riess, Adam G.; Challis, Peter M. +6 more
We report observations of two nearby Type Ia supernovae (SNe Ia) for which observations of Cepheid variables in the host galaxies have been obtained with the Hubble Space Telescope: SN 1994ae in NGC 3370 and SN 1998aq in NGC 3982. For NCG 3370, we used the Advanced Camera for Surveys to observe 64 Cepheids that yield a distance of 29 Mpc, the fart…
Multiphase High-Velocity Clouds toward HE 0226-4110 and PG 0953+414
Tripp, Todd M.; Sembach, Kenneth R.; Savage, Blair D. +3 more
We study the physical conditions, elemental abundances, and kinematics of the high-velocity clouds (HVCs) along the sight lines toward active galaxies HE 0226-4110 and PG 0953+414 using Hubble Space Telescope Space Telescope Imaging Spectrograph and Far Ultraviolet Spectroscopic Explorer data. No 21 cm H I emission is detected in these clouds, but…
Imaging Redshifts of BL Lacertae Objects
Sbarufatti, B.; Falomo, R.; Treves, A.
The HST snapshot imaging survey of 110 BL Lac objects (Urry et al.) has clearly shown that the host galaxies are massive and luminous ellipticals. The dispersion of the absolute magnitudes is sufficiently small that the measurement of the galaxy brightness becomes a valuable way of estimating their distance. This is illustrated by constructing a H…