Search Publications
Missions
Journals
Publication Years
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…
Eclipsing binaries as standard candles. HD 23642 and the distance to the Pleiades
Maxted, P. F. L.; Southworth, J.; Smalley, B.
We present a reanalysis of the light curves of HD 23642, a detached eclipsing binary star in the Pleiades open cluster, with emphasis on a detailed error analysis. We compare the masses and radii of the two stars to predictions of stellar evolutionary models and find that the metal and helium abundances of the Pleiades are approximately solar. We …
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…
The October 28, 2003 extreme EUV solar flare and resultant extreme ionospheric effects: Comparison to other Halloween events and the Bastille Day event
Tsurutani, B. T.; Didkovsky, L.; Judge, D. L. +16 more
Some of the most intense solar flares measured in 0.1 to 0.8 nm x-rays in recent history occurred near the end of 2003. The Nov 4 event is the largest in the NOAA records (X28) and the Oct 28 flare was the fourth most intense (X17). The Oct 29 flare was class X7. These flares are compared and contrasted to the July 14, 2000 Bastille Day (X10) even…
Titan's internal structure inferred from a coupled thermal-orbital model
Sotin, Christophe; Lunine, Jonathan I.; Tobie, Gabriel +2 more
Through coupled thermal and orbital calculations including a full description of tidal dissipation, heat transfer and the H 2O sbnd NH 3 phase diagram, we propose a model for the internal structure and composition of Titan testable with Cassini-Huygens measurements. The high value of Titan's orbital eccentricity provides a st…
On stars with weak winds: the Galactic case
Schaerer, D.; Martins, F.; Hillier, D. J. +3 more
We study the stellar and wind properties of a sample of Galactic O dwarfs to track the conditions under which weak winds (i.e. mass loss rates lower than 10-8 M⊙ yr-1) appear. The sample is composed of low and high luminosity dwarfs including Vz stars and stars known to display qualitatively weak winds. Atmosphere …
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 …
A statistical study of the properties of interplanetary coronal mass ejections from 0.3 to 5.4 AU
Liu, Y.; Richardson, J. D.; Belcher, J. W.
We make a comprehensive survey of interplanetary coronal mass ejections (ICMEs) observed by the Helios 1 and 2, Ulysses, WIND and ACE spacecraft, which together cover heliocentric distances from 0.3 to 5.4 AU. The signatures used to identify ICMEs are enhanced helium abundances and depressed proton temperatures. We use the ICME list to study the r…