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Linear polarization of the O VI lambda 1031.92 coronal line. II. Constraints on the magnetic field and the solar wind velocity field vectors in the coronal polar holes
Raouafi, N. -E.; Lemaire, P.; Sahal-Bréchot, S.
Numerical computation results of the linear polarization parameters of the O VI lambda1031 .92 coronal line are presented. They are based on theoretical results obtained by Raouafi (2002 and 2000), which give the Stokes parameters of a resonance scattering spectral line sensitive simultaneously to the Hanle effect and to the Doppler redistribution…
Optical and Near-Infrared Structural Properties of Cluster Galaxies at z ~ 0.3
Capaccioli, M.; La Barbera, F.; Merluzzi, P. +2 more
Structural parameters (half-light radius re, mean effective surface brightness <µ>e, and Sersic index n, parameterizing the light profile shape) are derived for a sample of galaxies in the rich cluster AC 118 at z=0.31, so far the largest (N=93) sample of galaxies at intermediate redshift with structural parameter…
Huygens' Surface Science Package
Leese, M. R.; Hathi, B.; Zarnecki, J. C. +2 more
The design and performance of the Surface Science Package (SSP) on the Huygens probe are discussed. This instrument consists of nine separate sensors that are designed to measure a wide range of physical properties of Titan's lower atmosphere, surface, and sub-surface. By measuring a number of physical properties of the surface it is expected that…
Chandra Observations of Galaxy Cluster A2218
Garmire, Gordon P.; Canizares, Claude; Bautz, Mark W. +1 more
We present results from two observations (combined exposure of ~17 ks) of galaxy cluster A2218 using the Advanced CCD Imaging Spectrometer on board the Chandra X-Ray Observatory that were taken on 1999 October 19. Using a Raymond-Smith single-temperature plasma model corrected for galactic absorption, we find a mean cluster temperature of kT=6.9+/…
ISOCAM mid-infrared detection of HR 10: A distant clone of Arp 220 at z = 1.44
Aussel, H.; Elbaz, D.; Duc, P. -A. +5 more
We report the detection of the extremely red object (ERO), HR 10 (I-K ~ 6.5, z=1.44), at 4.9 and 6.1 mu m (rest-frame) with ISOCAM, the mid-infrared (MIR) camera onboard the Infrared Space Observatory (ISO). HR 10 is the first ERO spectroscopically identified to be associated with an ultra-luminous IR galaxy (ULIG) detected in the radio, MIR and s…
Discovery of calcite in the solar type protostar NGC 1333-IRAS 4
Waters, L. B. F. M.; Ceccarelli, C.; Caux, E. +3 more
We present observations, obtained with ISO-LWS, of the continuum between 50-200 mu m of the solar type protostar IRAS 4, in the NGC 1333 complex. The continuum presents an excess, around 95 mu m, that we demonstrate must be a dust feature. We compared the 95 mu m excess with the calcite feature at 92 mu m and find that it fits the observations rea…
Quiescent Solar Prominences and Magnetic-Energy Storage
Low, B. C.; Fan, Y.; Fong, B.
Analytical solutions are presented to describe the hydromagnetic support of quiescent solar prominences treated as cold plasma sheets in the characteristic normal and inverse configurations. The solar corona is modeled to be axisymmetric outside a unit sphere, with the prominence sheet lying in the equatorial plane extending from the sphere out to…
Molecular Gas in Candidate Double-barred Galaxies. I. The Diverse Morphology and Dynamics of NGC 2273 and NGC 5728
Wilson, Christine D.; Petitpas, Glen R.
Double bars have been proposed as a means of transporting molecular gas past inner Lindblad resonances into the nuclear regions, where it can fuel active or starburst nuclei. Thus far, the existence of double bars has been determined predominantly through analysis of near-infrared images, which can tell us little about the dynamics and inflow rate…
Jupiter's Cloud Structure as Constrained by Galileo Probe and HST Observations
Sromovsky, L. A.; Fry, P. M.
The Galileo Probe sampled Jupiter's atmosphere at the edge of a 5-µm hot spot, where it found very little cloud opacity above the 700 mb level. Only τ=1-2 at λ=0.5 µm was inferred from Net Flux Radiometer observations (Sromovsky et al. 1998, J. Geophys. Res.103, 22,929-22,977), in seeming conflict with Chanover et al. (1997, Icarus128,…
Analysis of a delta spot
Liu, Y.; Zhang, H. Q.
delta -groups generally develop in three different ways: eruption of a single complex active region, eruption of large satellite spots near a large older spot, or collision of spots of opposite polarity from different dipoles. In this paper, we present a rare observational result in which a delta -spot forms from rapid coalescence of two opposite …