Search Publications

Discovery of pulsations from the Be/X-ray binary RXJ0101.3-7211 in the SMC by XMM-Newton
DOI: 10.1051/0004-6361:20010271 Bibcode: 2001A&A...369L..29S

Pietsch, W.; Haberl, F.; Sasaki, M. +1 more

We report pulsations in the X-ray flux of RX J0101.3-7211 in the Small Magellanic Cloud (SMC) with a period of (455+/-2) s in XMM-Newton EPIC-PN data. The X-ray spectrum can be described by a power-law with a photon index of 0.6+/-0.1. Timing analysis of ROSAT PSPC and HRI archival data confirms the pulsations and indicates a pe…

2001 Astronomy and Astrophysics
XMM-Newton 19
Dense gas and cold dust in the dark core B217
DOI: 10.1051/0004-6361:20010486 Bibcode: 2001A&A...372..302H

Lemke, D.; Walmsley, C. M.; Harju, J. +2 more

The Barnard object B217 was observed in the infrared and radio region. The 170 mu m continuum was detected with ISOPHOT, the ammonia 1.3 cm radio lines with the Effelsberg 100 m-telescope. Mapping B217SW in (J,K)=(1,1) and (2,2) inversion lines revealed the temperature and density distribution of the gas and made it possible to investigate the dyn…

2001 Astronomy and Astrophysics
ISO 19
Discovery of anomalous oxygen isotopic ratios in HR 4049
DOI: 10.1051/0004-6361:20000560 Bibcode: 2001A&A...367L...1C

Yamamura, I.; Cami, J.

We report the discovery in the ISO/SWS spectrum of the post-AGB star HR 4049 of emission bands due to 17O and 18O isotopes locked up in CO2 molecules. It is the first time these isotopomers are detected outside the solar system. Isotopic ratios derived in the optically thin limit are as low as

2001 Astronomy and Astrophysics
ISO 19
Long period variable stars: galactic populations and infrared luminosity calibrations
DOI: 10.1051/0004-6361:20010764 Bibcode: 2001A&A...374..968M

Luri, X.; Mowlavi, N.; Mennessier, M. O. +1 more

In this paper HIPPARCOS astrometric and kinematic data are used to calibrate both infrared luminosities and kinematical parameters of Long Period Variable stars (LPVs). Individual absolute K and IRAS 12 and 25 luminosities of 800 LPVs are determined and made available in electronic form. The estimated mean kinematics is analyzed in terms of galact…

2001 Astronomy and Astrophysics
Hipparcos 19
General relativistic satellite astrometry. II. Modeling parallax and proper motion
DOI: 10.1051/0004-6361:20010499 Bibcode: 2001A&A...373..336D

Lattanzi, M. G.; Bucciarelli, B.; Vecchiato, A. +1 more

The non-perturbative general relativistic approach to global astrometry introduced by de Felice et al. (\cite{defetal}) is here extended to account for the star motions on the Schwarzschild celestial sphere. A new expression of the observables, i.e. angular distances among stars, is provided, which takes into account the effects of parallax and pr…

2001 Astronomy and Astrophysics
Hipparcos 19
Cosmic shear from STIS pure parallels. I. Data
DOI: 10.1051/0004-6361:20010836 Bibcode: 2001A&A...375..351P

White, S. D. M.; Micol, A.; Fosbury, R. A. E. +9 more

Following the second HST servicing mission in 1997 when the STIS instrument was installed and the capability for parallel observations was enhanced, a substantial archive of non-proprietary parallel data has been accumulating. In this paper, we discuss the use of unfiltered STIS imaging data for a project that requires deep observations along as m…

2001 Astronomy and Astrophysics
eHST 18
WFPC2 observations of two dwarf spheroidal galaxies in the M 81 group
DOI: 10.1051/0004-6361:20010716 Bibcode: 2001A&A...375..359K

Sarajedini, A.; Dolphin, A. E.; Grebel, E. K. +7 more

We have obtained HST WFPC2 and ground-based images of two low surface brightness dwarf spheroidal galaxies in the M 81 group, FM1 and KKH57. Their colour-magnitude diagrams show red giant branches with tips at I = 23.77 +/- 0.14 and I = 23.97 +/-0.17, respectively. The derived true distance moduli, 27.66 +/- 0.16 and 27.96 +/- 0.19, agree well wit…

2001 Astronomy and Astrophysics
eHST 18
An optical inverse-Compton hotspot in 3C 196?
DOI: 10.1051/0004-6361:20010687 Bibcode: 2001A&A...373..881H

Hardcastle, M. J.

Several hotspots of FRII radio sources have previously been detected in the X-ray at a flux level consistent with the X-rays being due to inverse-Compton scattering of radio ``synchrotron photons synchrotron self-Compton'', if the magnetic fields in the hotspots are close to their equipartition values. However, the number of hotspots compact and b…

2001 Astronomy and Astrophysics
eHST 18
ORFEUS echelle spectra: Molecular hydrogen in disk, IVC, and HVC gas in front of the LMC
DOI: 10.1051/0004-6361:20000346 Bibcode: 2001A&A...367..299B

de Boer, K. S.; Marggraf, O.; Bluhm, H. +1 more

In front of the LMC molecular hydrogen is found in absorption near 0 km s-1, being local disk gas, near +60 km s-1 in an intermediate velocity cloud, and near +120 km s-1, being a high velocity halo cloud. The nature of the gas is discussed based on four Orfeus far UV spectra of LMC stars and including data from th…

2001 Astronomy and Astrophysics
IUE 18
High resolution spectroscopy of symbiotic stars. VI. Orbital and stellar parameters for AR Pavonis
DOI: 10.1051/0004-6361:20000338 Bibcode: 2001A&A...366..972S

Schmutz, W.; Nussbaumer, H.; Schild, H. +3 more

We present new dynamical parameters of the AR Pav binary system. Our observations consist of a series of high resolution optical/NIR spectra from which we derive the radial velocity curve of the red giant as well as its rotation velocity. Assuming co-rotation, we determine the stellar radius (130 Rsun) of the red giant. Based on this we…

2001 Astronomy and Astrophysics
IUE 18