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Radial velocities of dwarf spheroidal galaxies in the M 81 group
Burenkov, A. N.; Sharina, M. E.; Karachentsev, I. D.
Long-slit observations of 4 dwarf spheroidal galaxies in the M 81 group are presented. We have obtained the heliocentric velocity of a globular cluster candidate located near the center of DDO 78 to be 55 +/- 10 km s-1 by cross-correlation with template stars. We estimated a heliocentric radial velocity of -116 +/- 21 km s-1 …
Formation of Fe X-Fe XIV coronal lines in the accretion shock of T Tauri stars
Lamzin, S. A.; Stempels, H. C.; Piskunov, N. E.
Specific intensities of the strongest Fe x-Fe xiV\ coronal lines were calculated in the framework of our accretion shock model (Lamzin \cite{Lamzin1998}). These lines are formed in a region immediately behind the front of the accretion shock, therefore, the gas velocity in the line formation region is close to 1/4 of the infall velocity. It appear…
The coronal FeXXI lambda 1354.094 line in AB Doradus
Mewe, R.; Hakala, P.; Vilhu, O. +1 more
The active late-type star AB Doradus was observed in February 1996 with the Goddard High Resolution Spectrograph of the Hubble Space Telescope using the low resolution G140L grating. The observations covered one half of the star's rotation cycle (P = 0.514 d) with 11.5 min time resolution. The strong coronal FeXXI lambda 1354.094 line formed at 10…
Astrometric observations of inner Saturnian satellites
Poulet, F.; Sicardy, B.
This paper presents observations of four inner Saturnian satellites (SX = Janus, SXI = Epimetheus, SXVI = Prometheus and SXVII = Pandora) made in August and November 1995 during the Earth and Sun crossings of Saturn's ring plane, respectively. The August 1995 data combine data taken with the Adonis optics system mounted on the ESO 3.6-m telescope …
CCD measurements of visual double stars made with the 74 cm and 50 cm refractors of the Nice Observatory (2nd series)
Gili, R.; Bonneau, D.
We present 619 measurements of 606 visual double stars made by CCD imaging from 1996 to 1999 with the 74 cm and 50 cm refractors of the Nice observatory. Angular separation, position angle and magnitude difference are given. Magnitude differences estimated from CCD images are compared with magnitude differences given in the Hipparcos catalog. The …
Analysis of RGU photometry in selected Area 141
Karaali, S.; Buser, R.; Karatas, Y.
The South Galactic pole field SA141 is investigated by using the full calibration tools of RGU photometry. The observed RGU data are reduced to the standard system, and the separation of dwarfs and evolved stars is carried out by an empirical method. Stars are categorized into different metallicity classes and their absolute magnitutes are determi…
On the relation between the IR continuum and the active galactic nucleus in Seyfert galaxies
Prieto, M. A.; Pérez García, A. M.; Rodríguez Espinosa, J. M.
A sample of the brightest known Seyfert galaxies from the CfA sample is analyzed on the basis of ISO photometric and spectroscopic data. Regardless of the Seyfert type, the mid-IR continuum emission from these galaxies is found to be correlated with the coronal line emission arising in the nuclear active region. Conversely, the correlation degrade…
CCD astrometry of faint compact extragalactic radio sources. II.
Costa, E.
Optical positions relative to the Hipparcos Catalogue (ESA \cite{ESA97}) have been obtained for the optical counterparts of 28 faint (B ~ 20-23) southern compact extragalactic radio sources (CERS). Most of these sources are not adequately observable (or simply not visible) by means of direct photography with a conventional wide-field telescope, so…
ISOCAM 3-12 µm imaging of five galactic compact HII regions.
Zavagno, A.; Ducci, V.
We present 3-12 µm ISOCAM observations of the five Galactic compact H II regions Sh 61, Sh 138, Sh 152, Sh 156 and Sh 186. The unidentified infrared bands (UIBs) centred at 3.3, 6.2, 7.7, 8.6 and 11.2 µm -and underlying continuum -are imaged using the SW1, SW2, LW4, LW6 and LW8 filters. Images are also obtained at 5.985, 6.911, 8.222, …
The warm circumstellar envelope and wind of the G9 IIb star HR 6902
Reimers, D.; Baade, R.; Kirsch, T.
IUE observations of the eclipsing binary system HR 6902 obtained at various epochs spread over four years indicate the presence of warm circumstellar material enveloping the G9 IIb primary. The spectra show Si Iv and C Iv absorption up to a distance of 3.3 giant radii (Rg). Line ratio diagnostics yields an electron temperature of ~ 78 0…