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The ROSAT Bright Survey: II. Catalogue of all high-galactic latitude RASS sources with PSPC countrate CR > 0.2 s-1
We present a summary of an identification program of the more than 2000X-ray sources detected during the ROSAT All-Sky Survey (Voges et al.1999) at high galactic latitude, |b| > 30degr , with countrate above0.2 s-1. This program, termed the ROSAT Bright Survey RBS, isto more than 99.5% complete. A sub-sample of 931 sources with countrateabove 0.2 s-1 in the hard spectral band between 0.5 and 2.0keV is to 100% identified. The total survey area comprises 20391deg2 at a flux limit of 2.4 x 10-12 ergcm-2 s-1 in the 0.5 - 2.0 keV band. About 1500sources of the complete sample could be identified by correlating theRBS with SIMBAD and the NED. The remaining ~ 500 sources were identifiedby low-resolution optical spectroscopy and CCD imaging utilizingtelescopes at La Silla, Calar Alto, Zelenchukskaya and Mauna Kea. Apartfrom completely untouched sources, catalogued clusters and galaxieswithout published redshift as well as catalogued galaxies with unusualhigh X-ray luminosity were included in the spectroscopic identificationprogram. Details of the observations with an on-line presentation of thefinding charts and the optical spectra will be published separately.Here we summarize our identifications in a table which contains opticaland X-ray information for each source. As a result we present the mostmassive complete sample of X-ray selected AGNs with a total of 669members and a well populated X-ray selected sample of 302 clusters ofgalaxies with redshifts up to 0.70. Three fields studied by us remainwithout optical counterpart (RBS0378, RBS1223, RBS1556). While the firstis a possible X-ray transient, the two latter are isolated neutron starcandidates (Motch et al. 1999, Schwope et al. 1999).
| Radio continuum emission from stars: a catalogue update.
An updated version of my catalogue of radio stars is presented. Somestatistics and availability are discussed.
| A microwave survey of southern active stars
The results of a survey of 153 active-chromosphere stars made with theParkes 64-m telescope at 5.0/8.4 GHz from 1981 to 1987 are reported.Microwave emission was detected from 70 stars on at least one occasion,with the highest detection rate of 68 percent from the RS CVn group. TheCa II stars and Algol-type binaries yielded detection rates of 44 and 30percent, respectively. The maximum powers emitted by the stars at5.0/8.4 GHz ranged over five orders of magnitude, with a median of 2.5 x10 to the 10th W/Hz. The maximum brightness temperatures had a smallerrange of three orders of magnitude, with a median of 3.6 x 10 to the 9thK.
| An H-alpha survey of southern hemisphere active chromosphere stars
Because of the variety of extraordinary phenomena exhibited by activechromosphere objects, discovery of new, bright surface-active stars isof considerable importance. Ca II emission is a well-known signature ofchromospheric activity, serving even as one of the points of definitionof the class of RS CVn binary stars. In connection with the presentinvestigation, spectroscopic observations of 27 Ca II emission starshave been conducted. The observations make it possible to identifyunambiguously the most chromospherically active stars in the sample. Byobserving the H-alpha line, rather than H and K, it is possible todistinguish nine of these stars which are likely to be observationaltargets as interesting as the extremely surface active objects V711 Tauor FK Com. Of the 27 stars surveyed, two (HD 86005, HD 204128) showedH-alpha as an emission feature above continuum, with estimatedequivalent width 1-2 A.
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | טווס |
| התרוממות ימנית: | 20h18m35.09s |
| סירוב: | -65°51'27.1" |
| גודל גלוי: | 9.218 |
| תנועה נכונה: | -8.4 |
| תנועה נכונה: | -103 |
| B-T magnitude: | 10.23 |
| V-T magnitude: | 9.302 |
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