Search Publications
Discovery of a new quadruply lensed QSO: HS 0810+2554 - A brighter twin to PG 1115+080
Reimers, D.; Hagen, H. -J.; Baade, R. +2 more
We announce the probable discovery of a new very bright gravitationally lensed QSO,
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…
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…
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 …
A VLT/FORS2 spectroscopic survey in the HDF-S
Fontana, A.; Vanzella, E.; Grazian, A. +6 more
We report on low-resolution multi-object spectroscopy of 65 objects from I(AB) =~ 20 to I(AB) =~ 25 in the HDF-S obtained with the VLT Focal Reducer/low dispersion Spectrograph (FORS2). 18 objects belong to the HDF-S proper, i.e. the WFPC2 deep area. 15 high-redshift galaxies with 2.0 < z < 3.5 (10 in the HDF-S proper) have been identified. …
X-rays from the jet in 3C 273 : Clues from the radio-optical spectra
Meisenheimer, K.; Jester, S.; Röser, H. -J. +1 more
Using new deep VLA and HST observations of the large-scale jet in 3C 273 matched to 0.3 arcsec resolution, we have detected excess near-ultraviolet emission (lambda 300 nm) above a synchrotron cutoff spectrum accounting for the emission from radio through optical (lambda lambda 3.6 cm-620 nm). This necessitates a two-component model for the emissi…
A conspicuous tangential alignment of galaxies in a STIS Parallel Shear Survey field: A new dark-lens candidate?
White, S. D. M.; Fosbury, R. A. E.; Schneider, P. +6 more
We report the serendipituous discovery of a conspicuous alignment of galaxies in a field obtained through the STIS Parallel Shear Survey. This project collects randomly distributed 50'' x 50'' fields to investigate the cosmic shear effect on this scale. Analyzing the parallel observations having the Seyfert galaxy NGC 625 as primary target, we rec…
Detection of solid ammonia, methanol, and methane with ISOPHOT.
Ábrahám, P.; Henning, Th.; Lemke, D. +4 more
We report on a search for the NH3 inversion band at 9.0 mu m, the CH4 band at 7.7 mu m, and the CH3OH band at 9.7 mu m in the spectra of 10 heavily obscured stellar objects taken with the spectrophotometer ISOPHOT-S aboard the Infrared Space Observatory (ISO). Four of them show indications of the NH3 inv…
OH/IR stars in the inner bulge detected by ISOGAL
Blommaert, J. A. D. L.; Ganesh, S.; Omont, A. +6 more
We present a study of known OH/IR stars in the inner bulge, observed by the ISOGAL survey at lambda = 6.8 mu m and lambda = 14.9 mu m. Bolometric corrections and luminosities are computed, based on near and mid-infrared data. The vast majority of the sources exhibit mass-loss rates in the range: 3 x 10-7 up to a few times 10-5