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Ultraviolet-Optical Pixel Maps of Face-on Spiral Galaxies: Clues for Dynamics and Star Formation Histories
DOI: 10.1086/367820 Bibcode: 2003ApJ...586..923E

Conselice, Christopher J.; de Grijs, Richard; Windhorst, Rogier A. +8 more

Ultraviolet and optical images of the face-on spiral galaxies NGC 6753 and NGC 6782 reveal regions of strong ongoing star formation that are associated with structures traced by the old stellar populations. We use these images to construct NUV-(NUV-I814) pixel color-magnitude diagrams (pCMDs) that reveal plumes of pixels with strongly v…

2003 The Astrophysical Journal
eHST 18
Spatial and temporal fluctuations in sunspots derived from MDI data
DOI: 10.1051/0004-6361:20031119 Bibcode: 2003A&A...411..249S

Solanki, S. K.; Rüedi, I.

The penumbra radiates an energy flux that is 0.75-0.8 times the photospheric value. One mechanism proposed to bring this flux to the surface is interchange convection according to which hot flux tubes rise to the surface, lie horizontally there while they cool and finally sink down again. We search for possible signatures of such a process using t…

2003 Astronomy and Astrophysics
SOHO 18
Cassini plasma spectrometer measurements of Jovian bow shock structure
DOI: 10.1029/2002JA009517 Bibcode: 2003JGRA..108.1287S

Dougherty, Michele K.; Gurnett, Donald A.; Coates, Andrew J. +9 more

The Cassini spacecraft on its way to Saturn flew by Jupiter and crossed its bow shock more than forty times on the dusk-side of the planet, whereas the early missions targeting Jupiter explored the dawnside. Here we report the first results concerning these bow shock crossings, based on the measurements of the Cassini Plasma Spectrometer (CAPS), t…

2003 Journal of Geophysical Research (Space Physics)
Cassini 18
Response of the groove in heliospheric Lyman-alpha glow to latitude-dependent ionization rate
DOI: 10.1051/0004-6361:20031023 Bibcode: 2003A&A...408.1155B

Bzowski, M.

I study the model response of the latitudinal profile of the heliospheric Lyman-alpha glow to various profiles of the ionization rate. The two profiles are characterized by their range separately in the north and south hemisphere, and by the contrast between the equator values and north and south pole values. These parameters define a mesh of the …

2003 Astronomy and Astrophysics
SOHO 18
The Gravitational Lens B1608+656. I. V-, I-, and H-Band Hubble Space Telescope Imaging
DOI: 10.1086/345592 Bibcode: 2003ApJ...584..100S

Blandford, R. D.; Surpi, G.

We present a multiwavelength analysis of high-resolution observations of the quadruple lens B1608+656 from the Hubble Space Telescope archive, acquired with WFPC2 through filters F606W (V band) and F814W (I band) and with NIC1 in filter F160W (H band). In the three bands, the observations show extended emission from the four images of the source i…

2003 The Astrophysical Journal
eHST 18
The Quintuple Quasar: Radio and Optical Observations
DOI: 10.1086/374832 Bibcode: 2003ApJ...590...26W

Keeton, Charles R.; Winn, Joshua N.; Kochanek, Christopher S. +1 more

We present results from high-resolution radio and optical observations of PMN J0134-0931, a gravitational lens with a unique radio morphology and an extremely red optical counterpart. Our data support the theory of Keeton & Winn: five of the six observed radio components are multiple images of a single quasar, produced by a pair of lens galaxi…

2003 The Astrophysical Journal
eHST 18
Hα Impact Polarization Observed in a Gradual Flare
DOI: 10.1086/378123 Bibcode: 2003ApJ...596.1347H

Hanaoka, Y.

Linear polarization of the Hα line was detected in kernels of a gradual flare, which was accompanied by a filament eruption. The maximum degree of polarization of this flare exceeds 1%, and the orientation of the polarization is approximately perpendicular to the flare ribbons. These results can be explained with the assumption that the observed p…

2003 The Astrophysical Journal
SOHO 18
Hubble Space Telescope STIS Spectroscopy of the White Dwarfs in the Ultrashort-Period Dwarf Novae VY Aquarii and WX Ceti
DOI: 10.1086/345445 Bibcode: 2003ApJ...583..907S

Szkody, Paula; Howell, Steve B.; Sion, Edward M. +2 more

We present the results of a multicomponent synthetic spectral analysis of Hubble Space Telescope (HST) STIS spectra of the ultrashort-period dwarf novae VY Aqr and WX Ceti during their deep quiescence following their last superoutburst. The white dwarf in these extremely low accretion rate systems dominates the far-UV light. We find that the accre…

2003 The Astrophysical Journal
eHST 18
Ab initio Wavelengths and Oscillator Strengths for Cl X
DOI: 10.1238/Physica.Regular.067a00044 Bibcode: 2003PhyS...67...44B

Karpuškienė, R.; Bogdanovich, P.; Martinson, I.

Using the configuration interaction technique, the energy spectra of 2s22p4, 2s2p5, 2s22p33s, 2s22p33p, and 2s22p33d configurations of oxygen-like chlorine Cl X have been calculated. The obtained data are used for the evaluation of wavelengths and oscillator strengths of all possible one-electron and two-electron 2s22p33p-2s2p5 electric dipole tra…

2003 Physica Scripta
SOHO 17
RX J0042.3+4115: A stellar mass black hole binary identified in M 31
DOI: 10.1051/0004-6361:20030638 Bibcode: 2003A&A...405..505B

Kolb, U.; Borozdin, K. N.; Osborne, J. P. +1 more

Four XMM-Newton X-ray observations of the central region of the Andromeda Galaxy (M 31) have revealed an X-ray source that varies in luminosity over ~ 1-3x 1038 erg s-1 between observations and also displays significant variability over time-scales of a few hundred seconds. The power dens…

2003 Astronomy and Astrophysics
XMM-Newton 17