Search Publications

Hα-derived Star Formation Rates for the z = 0.84 Galaxy Cluster Cl J0023+0423B
DOI: 10.1086/381729 Bibcode: 2004ApJ...604..141F

Zaritsky, Dennis; Finn, Rose A.; McCarthy, Donald W., Jr.

We present Hα-derived star formation rates (SFRs) for the galaxy cluster Cl J0023+0423B at z=0.845. Our 3 σ flux limits correspond to an SFR of 0.24 h-2100 Msolar yr-1, and our minimum reliable Hα+[NII] equivalent width is greater than 10 Å, demonstrating that near-infrared narrowband imaging can sample …

2004 The Astrophysical Journal
eHST 38
Evolution in the Colors of Lyman Break Galaxies from z~4 to z~3
DOI: 10.1086/381075 Bibcode: 2004ApJ...600L.111P

Papovich, Casey; Dickinson, Mark; Ferguson, Henry C. +11 more

The integrated colors of distant galaxies provide a means for interpreting the properties of their stellar content. Here we use rest-frame UV-to-optical colors to constrain the spectral energy distributions and stellar populations of color-selected, B-dropout galaxies at z~4 in the Great Observatories Origins Deep Survey (GOODS). We combine the Ad…

2004 The Astrophysical Journal
eHST 38
Far-Ultraviolet Spectroscopic Analyses of Four Central Stars of Planetary Nebulae
DOI: 10.1086/421010 Bibcode: 2004ApJ...609..378H

Bianchi, L.; Herald, J. E.

We analyze the far-UV/UV spectra of four central stars of planetary nebulae (CSPNs) with strong wind features-NGC 2371, A78, IC 4776, and NGC 1535-and derive their photospheric and wind parameters by modeling high-resolution FUSE (Far Ultraviolet Spectroscopic Explorer) data in the far-UV and HST (Hubble Space Telescope) STIS and IUE data in the U…

2004 The Astrophysical Journal
IUE eHST 38
O VI, N V, and C IV in the Galactic Halo. II. Velocity-Resolved Observations with the Hubble Space Telescope and Far Ultraviolet Spectroscopic Explorer
DOI: 10.1086/383465 Bibcode: 2004ApJ...607..309I

Shull, J. Michael; Indebetouw, Rémy

We present a survey of N V and O VI (and, where available, C IV) in the Galactic halo, using data from the Far Ultraviolet Spectroscopic Explorer (FUSE) and the Hubble Space Telescope (HST) along 34 sight lines. These ions are usually produced in nonequilibrium processes such as shocks, evaporative interfaces, or rapidly cooling gas, and thus trac…

2004 The Astrophysical Journal
eHST 38
XMM-Newton Observations of A133: A Weak Shock Passing through the Cool Core
DOI: 10.1086/424807 Bibcode: 2004ApJ...616..157F

Sarazin, Craig L.; Reiprich, Thomas H.; Ehle, M. +5 more

We use XMM-Newton observations of the cluster of galaxies A133 to study the X-ray spectrum of the intracluster medium (ICM). We find a cold front to the southeast of the cluster core. From the pressure profile near the cold front, we derive an upper limit to the velocity of the core relative to the rest of the cluster of less than 230 km s-1<…

2004 The Astrophysical Journal
XMM-Newton 37
A Comparison of the Outer Atmosphere of the ``Flat Activity'' Star τ Ceti (G8 V) with the Sun (G2 V) and α Centauri A (G2 V)
DOI: 10.1086/421044 Bibcode: 2004ApJ...609..392J

Ayres, Thomas R.; Judge, Philip G.; Carlsson, Mats +1 more

Driven by the desire to understand the roles of acoustic and magnetic mechanisms in heating the outer atmospheres of Sun-like stars, we compare solar UV spectra with archival STIS spectra from the Hubble Space Telescope of α Cen A (G2 V) and new STIS spectra of the extremely inactive dwarf star τ Cet (G8 V, V=3.5). The activity of τ Cet shows occa…

2004 The Astrophysical Journal
IUE SOHO eHST 37
Discovery of a Soft Spectral Component and Transient 22.7 Second Quasi-periodic Oscillations of SAX J2103.5+4545
DOI: 10.1086/424825 Bibcode: 2004ApJ...616..463I

Baykal, A.; İnam, S. Ç.; Swank, J. +1 more

XMM-Newton observed SAX J2103.5+4545 on 2003 January 6, while the Rossi X-Ray Timing Explorer (RXTE) was also monitoring the source. Using the RXTE Proportional Counter Array data set between 2002 December 3 and 2003 January 29, the spin period and average spin-up rate during the XMM-Newton observations were found to be 354.7940+/-0.0008 s and (7.…

2004 The Astrophysical Journal
XMM-Newton 37
Observations of Cold Dust in Nearby Elliptical Galaxies
DOI: 10.1086/422795 Bibcode: 2004ApJ...612..837L

Kuno, Nario; Haas, Martin; Sansom, Anne E. +2 more

Spectral energy distribution (SED) analyses that include new millimeter to far-infrared (FIR) observations obtained with continuum instruments on the Nobeyama and James Clerk Maxwell Telescopes and the Infrared Space Observatory are presented for seven nearby (<45 Mpc) FIR-bright elliptical galaxies. These are analyzed together with archival FI…

2004 The Astrophysical Journal
ISO 37
Infrared Surface Brightness Fluctuations of Magellanic Star Clusters
DOI: 10.1086/421968 Bibcode: 2004ApJ...611..270G

Liu, Michael C.; Bruzual A., Gustavo; González, Rosa A.

We present surface brightness fluctuations (SBFs) in the near-IR for 191 Magellanic star clusters available in the Second Incremental and All Sky Data releases of the Two Micron All Sky Survey (2MASS) and compare them with SBFs of Fornax Cluster galaxies and with predictions from stellar population models as well. We also construct color-magnitude…

2004 The Astrophysical Journal
eHST 37
The Nitrogen Isotopic Ratio in Jupiter's Atmosphere from Observations by the Composite Infrared Spectrometer on the Cassini Spacecraft
DOI: 10.1086/381084 Bibcode: 2004ApJ...602.1063A

Flasar, F. M.; Owen, T.; Achterberg, R. K. +9 more

The Composite Infrared Spectrometer (CIRS) on the Cassini spacecraft made infrared observations of Jupiter's atmosphere during the flyby of 2000 December to 2001 January. The unique database in the 600-1400 cm-1 region with 0.53 and 2.8 cm-1 spectral resolutions obtained from the observations permits retrieval of global maps …

2004 The Astrophysical Journal
Cassini 37