Science Archives Publication System

A Population of Massive Globular Clusters in NGC 5128

DOI: 10.1086/421458 Bibcode: 2004ApJ...610..233M

Ho, Luis C.; Martini, Paul

We present velocity dispersion measurements of 14 globular clusters in NGC 5128 (Centarus A) obtained with the MIKE echelle spectrograph on the 6.5 m Magellan Clay telescope. These clusters are among the most luminous globular clusters in NGC 5128 and have velocity dispersions comparable to the most massive clusters known in the Local Group, rangi…

2004 • The Astrophysical Journal

eHST 75

Identification of Type Ia Supernovae at Redshift 1.3 and Beyond with the Advanced Camera for Surveys on the Hubble Space Telescope

DOI: 10.1086/378311 Bibcode: 2004ApJ...600L.163R

Dickinson, Mark; Ferguson, Henry C.; Giavalisco, Mauro +15 more

We present discoveries of Type Ia supernovae (SNe Ia) at z>1 and the photometric diagnostic used to discriminate them from other types of SNe detected during the Great Observatories Origins Deep Survey (GOODS) Hubble Space Telescope Treasury Program with the Advanced Camera for Surveys (ACS). Photometric redshift measurements of the hosts combi…

2004 • The Astrophysical Journal

eHST 74

ISOCAM survey and dust models of 3CR radio galaxies and quasars

DOI: 10.1051/0004-6361:20035908 Bibcode: 2004A&A...421..129S

Siebenmorgen, R.; Haas, M.; Freudling, W. +1 more

We present a survey of all 3CR sources imaged with ISOCAM onboard the Infrared Space Observatory (ISO). The sample consists mostly of radio-loud active galactic nuclei (AGN). For each source, we present spatially integrated mid-infrared (MIR, 5-18 µm) fluxes measured from newly calibrated ISOCAM images. In total, we detected 68 objects of th…

2004 • Astronomy and Astrophysics

ISO 74

Transition region small-scale dynamics as seen by SUMER on SOHO

DOI: 10.1051/0004-6361:20040503 Bibcode: 2004A&A...427.1065T

Doyle, J. G.; Madjarska, M. S.; Teriaca, L. +2 more

High spectral, spatial and temporal resolution UV observations of the quiet Sun transition region show a highly structured and dynamical environment where transient supersonic flows are commonly observed. Strongly non-Gaussian line profiles are the spectral signatures of these flows and are known in the literature as explosive events. In this pape…

2004 • Astronomy and Astrophysics

SOHO 74

Supersoft X-Ray Sources in M31. I. A Chandra Survey and an Extension to Quasi-soft Sources

DOI: 10.1086/421696 Bibcode: 2004ApJ...610..247D

Barmby, P.; Greiner, J.; Murray, S. S. +9 more

We report on very soft X-ray sources (VSSs) in M31. In a survey that was most sensitive to soft sources in four 8^'×8^' regions covered by Chandra's ACIS-S S3 CCD, we find 33 VSSs that appear to belong to M31. Fifteen VSSs have spectral characteristics mirroring the supersoft X-ray sources studied in the Magellanic Clouds and M…

2004 • The Astrophysical Journal

XMM-Newton eHST 74

A joint mid-infrared spectroscopic and X-ray imaging investigation of LINER galaxies

DOI: 10.1051/0004-6361:20031609 Bibcode: 2004A&A...414..825S

Dudik, R. P.; Satyapal, S.; Sambruna, R. M.

We present a comprehensive comparative high resolution mid-IR spectroscopic and X-ray imaging investigation of LINERs using archival observations from the ISO-SWS and the Chandra Advanced CCD Imaging Spectrometer. Although the sample is heterogenous and incomplete, this is the first comprehensive study of the mid-infrared fine structure line emiss…

2004 • Astronomy and Astrophysics

ISO 74

Interpretation of Cluster data on chorus emissions using the backward wave oscillator model

DOI: 10.1063/1.1667495 Bibcode: 2004PhPl...11.1345T

Trakhtengerts, V. Y.; Demekhov, A. G.; Titova, E. E. +4 more

The measurements of chorus emissions by four closely separated Cluster spacecraft provide important information concerning the chorus generation mechanism. They confirm such properties of the wave source as their strong localization near the equatorial cross section of a magnetic flux tube, an almost parallel average wave-vector direction with res…

2004 • Physics of Plasmas

Cluster 74

Magnetic Fields in the Solar Convection Zone

DOI: 10.12942/lrsp-2004-1 Bibcode: 2004LRSP....1....1F

Fan, Yuhong

Recent studies of the dynamic evolution of magnetic flux tubes in the solar convection zone are reviewed with focus on emerging flux tubes responsible for the formation of solar active regions. The current prevailing picture is that active regions on the solar surface originate from strong toroidal magnetic fields generated by the solar dynamo mec…

2004 • Living Reviews in Solar Physics

SOHO 74

A phase-dependent absorption line in the spectrum of the X-ray pulsar RX J0720.4-3125

DOI: 10.1051/0004-6361:20034129 Bibcode: 2004A&A...419.1077H

Haberl, F.; Burwitz, V.; Trümper, J. +1 more

The XMM-Newton spectra of the isolated neutron star RX J0720.4-3125 show deviations from a Planckian energy distribution below 400 eV, similar to the spectra of RBS1223, another long-period X-ray pulsar, as reported recently by \citet{2003A&A...403L..19H. For a Gaussian-shaped absorption line we derive an energy of 271 eV an…

2004 • Astronomy and Astrophysics

XMM-Newton 74

Determination of magnetic helicity content of solar active regions from SOHO/MDI magnetograms

DOI: 10.1007/s11207-004-0938-9 Bibcode: 2004SoPh..223...39C

Moon, Yong-Jae; Chae, Jongchul; Park, Young-Deuk

Chae (2001) first proposed a method of self-consistently determining the rate of change of magnetic helicity using a time series of longitudinal magnetograms only, such as taken by SOHO/MDI. Assuming that magnetic fields in the photosphere are predominantly vertical, he determined the horizontal component of velocity by tracking the displacements …

2004 • Solar Physics

SOHO 73