Inici     Començant     Sobreviure a l'Univers    
Inhabited Sky
    News@Sky     Astro Fotografia     La Col·lecció     Fòrum     Blog New!     FAQ     Premsa     Login  

HD 87432


Contingut

Imatges

Carregar la teva Imatge

DSS Images   Other Images


Articles Relacionats

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

First CCD measurements in the {DELTA}a system for detecting CP2 stars.
This is the first time that CCD-photometry in the three filter {DELTA}asystem (Maitzen, 1976A&A....52..223M) was carried out after twodecades of classical photoelectric photometry. The aim is to extend thesuccessful search for chemically peculiar stars to more and distant openclusters as well as far galactic fields. In this paper we presentCCD-photometry for a sample of 25 field stars with publishedspectroscopic peculiarity types. 22 of them show discordance betweentheir Michigan catalogue types (non-peculiar) and the Bidelman &MacConnell (1973AJ.....78..678B; BC) peculiarity assignments. Eightstars are peculiar in {DELTA}a (five of them also in the Geneva index{DELTA}(V1-G)) thus supporting BC, mainly among their Silicon stardiscoveries. Considering cases where Silicon line enhancements wereinterpreted as peculiar instead as indicator of higher luminosity by BC,and the perfect detection of the three unambiguous peculiar stars, inaddition to the achievement of an accuracy of 0.003mags, we arejustified to conclude that the performance of our CCD-{DELTA}aphotometry perfectly matches the requirements of the conventionalphotometric technique and thus opens the way to observations of fainterstars.

Enviar un nou article


Enllaços Relacionats

  • - No s'ha trobat enllaços -
Enviar un nou enllaç


Membre dels grups següents:


Dades d'Observació i Astrometria

Constel·lació:Vela
Ascensió Recta:10h03m44.92s
Declinació:-45°45'47.2"
Magnitud Aparent:9.179
Moviment propi RA:-14.8
Moviment propi Dec:3.1
B-T magnitude:9.334
V-T magnitude:9.192

Catàlegs i designacions:
Noms Propis   (Edit)
HD 1989HD 87432
TYCHO-2 2000TYC 8182-620-1
USNO-A2.0USNO-A2 0375-09969033
HIPHIP 49298

→ Sol·licitar més catàlegs i designacions de VizieR