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Hipparcos red stars in the HpV_T2 and V I_C systems
For Hipparcos M, S, and C spectral type stars, we provide calibratedinstantaneous (epoch) Cousins V - I color indices using newly derivedHpV_T2 photometry. Three new sets of ground-based Cousins V I data havebeen obtained for more than 170 carbon and red M giants. These datasetsin combination with the published sources of V I photometry served toobtain the calibration curves linking Hipparcos/Tycho Hp-V_T2 with theCousins V - I index. In total, 321 carbon stars and 4464 M- and S-typestars have new V - I indices. The standard error of the mean V - I isabout 0.1 mag or better down to Hp~9 although it deteriorates rapidly atfainter magnitudes. These V - I indices can be used to verify thepublished Hipparcos V - I color indices. Thus, we have identified ahandful of new cases where, instead of the real target, a random fieldstar has been observed. A considerable fraction of the DMSA/C and DMSA/Vsolutions for red stars appear not to be warranted. Most likely suchspurious solutions may originate from usage of a heavily biased color inthe astrometric processing.Based on observations from the Hipparcos astrometric satellite operatedby the European Space Agency (ESA 1997).}\fnmsep\thanks{Table 7 is onlyavailable in electronic form at the CDS via anonymous ftp tocdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/397/997
| Li-rich giants: A survey based on IRAS colours
In a previous work we studied the IRAS colours of known Li-rich redgiants and showed that they have flux ratiosF12/F25 and F25/F60 in welldefined ranges. By using this result as a selection criterion, weprepared a list of 280 IRAS Point Source candidates to be Li-rich giantstars. Up to the present we have obtained spectra for 57% of our targetlist. We identified five stars showing a strong LiI 670.079 nm line andsix ones with a Li line of medium strength. Most of the candidates showfeatures typical of normal giants having circumstellar dust, asindicated by their IRAS colours. Observations collected at theLaboratorio Nacional de Astrofisica - LNA, Brazil; Observatoire de HauteProvence - OHP, France; European Southern Observatory - ESO, Chile.
| Hyades and Sirius supercluster members brighter than magnitude (V) 7.1. II - Right ascension six to twelve hours
The present star sample is contained in the Bright Star Catalogue andits Supplement, augmented with a further supplement of 788 stars foundduring various observing programs over the past 40 years. Accurate,four-color and H-beta, or (RI), photometry is available for most of thesupercluster members. The criteria for membership are the comparisons ofthe proper motion, radial velocity, and luminosity obtained from thesupercluster parameters with the observed motions and the luminosityderived from the photometric parameters. New proper motions, based onall available catalogs, have been derived for the additional 788 starsdiscussed here, as well as all supercluster members.
| Estrellas Rojas entre Popa y Cruz.
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Membro dei seguenti gruppi:
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Osservazione e dati astrometrici
| Costellazione: | Poppa |
| Ascensione retta: | 08h17m46.15s |
| Declinazione: | -36°04'03.3" |
| Magnitudine apparente: | 6.52 |
| Distanza: | 1315.789 parsec |
| Moto proprio RA: | -1.7 |
| Moto proprio Dec: | 3.2 |
| B-T magnitude: | 8.416 |
| V-T magnitude: | 6.677 |
Cataloghi e designazioni:
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