Search Publications
Study of the Per OB2 star-forming complex. I. The Compiled Catalogue of kinematic and photometric data
Scholz, R. -D.; Yatsenko, A. I.; Piskunov, A. E. +3 more
In this paper we describe the construction of a Compiled Catalogue (CC) of about 30 000 stars in a nearby region of star formation including the Per OB2 association. The CC is a photometric and astrometric survey with the center at (alpha ,delta )_J2000=(3h51m36s, 34o36arcmin ) and radius of 10 degrees. …
Systematic errors in measuring solar magnetic fields with a FPI spectrometer and MDI
Carroll, T. A.; Norton, A. A.; Settele, A. +1 more
We will show the potential errors of observations using instruments, where a line spectrum is obtained not instantly but by scanning through the spectral line in time. We give two examples in simulations of a sunspot observation with the measuring procedure of a typical Fabry-Perot interferometer (FPI) spectrometer and the Michelson Doppler Imager…
A revision of the fundamental parameters of the open cluster Hogg 15 and the projected star WR 47
Bica, E.; Piatti, A. E.; Santos, J. F. C., Jr. +1 more
We revise the fundamental parameters of the faint open cluster Hogg 15, for which two recent colour-magnitude diagram (CMD) studies have obtained significantly different ages. In the present study, we combine a series of methods trying to constrain age, together with other fundamental parameters. We employ spatial extractions to construct the CMDs…
XMM-Newton observation of the bursting pulsar GRO J1744-28 in quiescence
Goldoni, P.; Decourchelle, A.; Warwick, R. S. +3 more
The XMM-Newton X-ray observatory performed a pointed observation of the bursting pulsar GRO J1744-28 in April 2001 for about 10 ks during a program devoted to the scan of the Galactic center region. After the discovery of this source by BATSE in December 1995 during a very active bursting phase, it has been in quiescence since April 1997. We prese…
NGC 6994 - clearly not a physical stellar ensemble
Soubiran, C.; Odenkirchen, M.
The sparse stellar ensemble NGC 6994 = M 73 has recently been discussed as a possible remnant of an old open cluster. In order to solve the controversy regarding the nature of this object we have taken high-resolution spectra of the six brightest stars within 6' angular distance of its nominal position. These stars are the only obvious candidate m…
Asteroid (216) Kleopatra. Tests of the radar-derived shape model
Lattanzi, M.; Tanga, P.; Berthier, J. +5 more
The shape model of Ostro et al. (\cite{ostro00}) for
Photocentric orbits from a direct combination of ground-based astrometry with Hipparcos. I. Comparison with known orbits
Gontcharov, G. A.; Kiyaeva, O. V.
Complementing the Proper Motions of Fundamental Stars catalogue by Gontcharov et al. (CDS, I-266) the photocentric orbits of some FK5/Hipparcos stars are calculated in a direct combination of the Hipparcos data with astrometric ground-based observational catalogues having epochs later than 1939. Some capabilities and limitations of this method are…
A high-resolution study of the evolution of the Lyman alpha forest in the redshift interval 0.9 < z < 1.7
Reimers, D.; Janknecht, E.; Baade, R.
Spectroscopy with HST/STIS Echelle and VLT/UVES of the bright QSO HE 0515-4414 (zem =1.73, B = 15.0) offers for the first time the opportunity to study the Lyman alpha forest in the redshift range 0.9 < z < 1.7 at a resolution <=10 km s-1. The number density evolution of the Lyman alpha lines is well described by the…
Relation between dust and radio luminosity in optically selected early type galaxies
Jaffe, W.; Krajnović, D.
We have surveyed an optical/IR selected sample of nearby E/S0 galaxies with and without nuclear dust structures with the VLA at 3.6 cm to a sensitivity of 100 mu Jy. We can construct a Radio Luminosity Function (RLF) of these galaxies to ~ 1019 W Hz-1 and find that ~ 50% of these galaxies have AGNs at this level. The space de…
Multiwavelength optical observations of chromospherically active binary systems. IV. The X-ray/EUV selected binary BK Psc (2RE J0039+103)
Montes, D.; López-Santiago, J.; Cornide, M. +3 more
We present high resolution echelle spectra taken during four observing runs from 1999 to 2001 of the recently X-ray/EUV selected chromospherically active binary BK Psc (2RE J0039+103). Our observations confirm the single-lined spectroscopic binary (SB1) nature of this system and allow us to obtain, for the first time, the orbital solution of the s…