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Characterizing the Stellar Population in NGC 1705-1
DOI: 10.1086/379805 Bibcode: 2004ApJ...600..162V

Martin, Crystal L.; Heckman, Timothy M.; Meurer, Gerhardt R. +4 more

We observed the brightest super-star cluster NGC 1705-1 in the nearby dwarf galaxy NGC 1705 with the Space Telescope Imaging Spectrograph in the echelle mode between 1200 and 3100 Å. The data allow a study of the young stellar population at hitherto unprecedented spectral resolution and signal-to-noise ratios. A comprehensive list of strong and we…

2004 The Astrophysical Journal
eHST 41
XMM-Newton spectral and timing observations of the millisecond pulsar PSR J0218+4232
DOI: 10.1051/0004-6361:20040032 Bibcode: 2004A&A...417..181W

Webb, N. A.; Barret, D.; Olive, J. -F.

We present XMM-Newton MOS imaging and PN timing data of the millisecond pulsar PSR J0218+4232. We confirm the previously detected pulsations of PSR J0218+4232 and we show that the folded lightcurve is dependent on energy. We present the broad band (0.2-10.0 keV) spectrum of this millisecond pulsar, as well as …

2004 Astronomy and Astrophysics
XMM-Newton 41
A Comparison of CME-Associated Atmospheric Waves Observed in Coronal (Fe XII 195 Å) and Chromospheric (He I 10830 Å) Lines
DOI: 10.1086/383231 Bibcode: 2004ApJ...607..540G

Gilbert, Holly R.; Thompson, Barbara J.; Holzer, Thomas E. +1 more

Although ``Moreton'' waves have historically been observed in Hα data, more recently waves have also been observed in chromospheric He I λ10830 images obtained at the Mauna Loa Solar Observatory. In an effort to better understand the nature of chromospheric waves and their relationship to coronal waves observed in EUV Imaging Telescope (EIT) data,…

2004 The Astrophysical Journal
SOHO 41
Separators in 3D Quiet-Sun Magnetic Fields
DOI: 10.1007/s11207-004-3259-0 Bibcode: 2004SoPh..225...21C

Priest, E. R.; Parnell, C. E.; Close, R. M.

At the confluence of four regions of different magnetic connectivity lies a distinct topological candidate for coronal heating, namely the magnetic separator. In this study, a method for tracing separator curves is developed and the statistical properties of separators in coronal fields are subsequently explored by analysing a model field with an …

2004 Solar Physics
SOHO 41
The Complex Neutral Gas Dynamics of the Dwarf Starburst Galaxy NGC 625
DOI: 10.1086/383408 Bibcode: 2004ApJ...607..274C

Cannon, John M.; Skillman, Evan D.; McClure-Griffiths, N. M. +1 more

We present new multiconfiguration H I aperture synthesis imaging of the nearby dwarf starburst galaxy NGC 625 obtained with the Australia Telescope Compact Array. Total H I column density images show gas well aligned with the optical major axis and low column density H I extending to greater than 6 optical scale lengths. The H I velocity field, on…

2004 The Astrophysical Journal
eHST 41
High-z massive galaxies in the Hubble Deep Field South
DOI: 10.1051/0004-6361:20040101 Bibcode: 2004A&A...420..125S

Fontana, A.; Vanzella, E.; Cristiani, S. +6 more

A census of massive galaxies at redshift increasingly higher than z∼1 may provide strong constraints for the history of mass assembly and star formation. Here we report the analysis of three galaxies selected in the Hubble Deep Field South at K s≤22 on the basis of their unusually red near-IR color J-K≥3. We have used population synthesis models t…

2004 Astronomy and Astrophysics
eHST 40
XMM-Newton EPIC observation of the galaxy cluster A 3667
DOI: 10.1051/0004-6361:20035812 Bibcode: 2004A&A...426....1B

Finoguenov, A.; Briel, U. G.; Henry, J. P.

The Abell cluster of galaxies A 3667 was observed with XMM-Newton in 6 partially overlapping pointings. We present here the resulting X-ray surface brightness, temperature, entropy and pressure maps and discuss the structure of this cluster on scales from 0.1 to 30 arcmin. Based on these observations we refine the origin of the A 3667 cold front t…

2004 Astronomy and Astrophysics
XMM-Newton 40
The Spectral Energy Distribution and Emission-Line Properties of the Narrow-Line Seyfert 1 Galaxy Arakelian 564
DOI: 10.1086/381235 Bibcode: 2004ApJ...602..635R

Brandt, W. N.; Kriss, G. A.; Turner, T. J. +11 more

We present the intrinsic spectral energy distribution (SED) of the narrow-line Seyfert 1 galaxy (NLS1) Ark 564, constructed with contemporaneous data obtained during a multiwavelength, multisatellite observing campaign in 2000 and 2001. We compare this SED with that of the NLS1 Ton S180 and with those obtained for broad-line Seyfert 1 galaxies to …

2004 The Astrophysical Journal
eHST 40
Hubble Space Telescope WFPC2 Study of the Trapezium Cluster: The Influence of Circumstellar Disks on the Initial Mass Function
DOI: 10.1086/383141 Bibcode: 2004ApJ...606..952R

Panagia, N.; Robberto, M.; Song, J. +3 more

We have performed the first measures of mass accretion rates in the core of the Orion Nebula Cluster. Four adjacent fields centered on the Trapezium stars have been imaged in the U and B bands using the Wide Field Planetary Camera 2 (WFPC2) on board the Hubble Space Telescope. We obtained photometry for 91 stars in the U band (F336W) and 71 stars …

2004 The Astrophysical Journal
eHST 40
A study of the expanding envelope of Nova V1974 Cyg 1992 based on IUE high resolution spectroscopy
DOI: 10.1051/0004-6361:20034102 Bibcode: 2004A&A...420..571C

Altamore, A.; Rossi, C.; González-Riestra, R. +2 more

We have carried out a detailed analysis of the IUE archival high resolution spectra of the classical nova V1974 Cyg 1992. The main UV resonance lines show P Cygni profiles in the first days, which change into symmetric pure emission lines, and then slowly become fainter and narrower. Lines of higher ionization species reach their peak luminosity l…

2004 Astronomy and Astrophysics
IUE 40