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The University of New South Wales Extrasolar Planet Search: a catalogue of variable stars from fields observed between 2004 and 2007
We present a new catalogue of variable stars compiled from the datataken for the University of New South Wales Extrasolar Planet Search.From 2004 October to 2007 May, 25 target fields were each observed forone to four months, resulting in ~87000 high-precision light curves with1600-4400 data points. We have extracted a total of 850 variable lightcurves, 659 of which do not have a counterpart in the General Catalogueof Variable Stars, the New Suspected Variables catalogue or the All SkyAutomated Survey southern variable star catalogue. The catalogue isdetailed here, and includes 142 Algol-type eclipsing binaries, 23 ?Lyrae-type eclipsing binaries, 218 contact eclipsing binaries, 53 RRLyrae stars, 26 Cepheid stars, 13 rotationally variable active stars,153 uncategorized pulsating stars with periods <10 d, including? Scuti stars, and 222 long period variables with variability ontime-scales of >10 d. As a general application of variable starsdiscovered by extrasolar planet transit search projects, we discussseveral astrophysical problems which could benefit from carefullyselected samples of bright variables. These include (i) the quest forcontact binaries with the smallest mass ratio, which could be used totest theories of binary mergers; (ii) detached eclipsing binaries withpre-main-sequence components, which are important test objects forcalibrating stellar evolutionary models and (iii) RR Lyrae-typepulsating stars exhibiting the Blazhko effect, which is one of the lastgreat mysteries of pulsating star research.
| The 74th Special Name-list of Variable Stars
We present the Name-list introducing GCVS names for 3153 variable starsdiscovered by the Hipparcos mission.
| New variable chemically peculiar stars identified in the HIPPARCOS archive
Since variability of chemically peculiar (CP) stars plays an importantrole for the astrophysical explanation of their outstanding behaviour,we have identified new variable CP stars listed in Renson's catalogueusing the extensive Hipparcos Variability Annex. From the 293 objectsfound, 33 were excluded because they are no CP stars and/or have noperiod listed, half of the remaining stars are newly identified and halfhad been already included in the catalogue of variable CP stars by\cite[Catalano & Renson (1997).]{Ca} Most of the newly identifiedvariability is due to an apparent magnetic field coupled with stellarrotation (oblique rotator model). The constraints of this model arefulfilled for all but three CP2 stars. Variations of bona fide Am-Fmstars are exclusively explained by eclipses of binary systems.Furthermore eight candidates of the >~mma Doradus group (pulsatingAm-Fm stars) were detected. Based on data from the ESA Hipparcosastrometry satellite. Table 1 is also available in electronic form atthe CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) orvia\break http://cdsweb.u-strasbg.fr/Abstract.html
| The HR-diagram from HIPPARCOS data. Absolute magnitudes and kinematics of BP - AP stars
The HR-diagram of about 1000 Bp - Ap stars in the solar neighbourhoodhas been constructed using astrometric data from Hipparcos satellite aswell as photometric and radial velocity data. The LM method\cite{luri95,luri96} allows the use of proper motion and radial velocitydata in addition to the trigonometric parallaxes to obtain luminositycalibrations and improved distances estimates. Six types of Bp - Apstars have been examined: He-rich, He-weak, HgMn, Si, Si+ and SrCrEu.Most Bp - Ap stars lie on the main sequence occupying the whole width ofit (about 2 mag), just like normal stars in the same range of spectraltypes. Their kinematic behaviour is typical of thin disk stars youngerthan about 1 Gyr. A few stars found to be high above the galactic planeor to have a high velocity are briefly discussed. Based on data from theESA Hipparcos astrometry satellite and photometric data collected in theGeneva system at ESO, La Silla (Chile) and at Jungfraujoch andGornergrat Observatories (Switzerland). Tables 3 and 4 are onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
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Dades d'Observació i Astrometria
| Constel·lació: | Ara |
| Ascensió Recta: | 17h18m45.11s |
| Declinació: | -57°26'20.6" |
| Magnitud Aparent: | 8.274 |
| Distancia: | 200.803 parsecs |
| Moviment propi RA: | -8.9 |
| Moviment propi Dec: | -20.2 |
| B-T magnitude: | 8.314 |
| V-T magnitude: | 8.278 |
Catàlegs i designacions:
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