Contenuti
Immagini
Carica la tua immagine
DSS Images Other Images
Articoli relazionati
Effective temperature scale and bolometric corrections from 2MASS photometry
We present a method to determine effective temperatures, angularsemi-diameters and bolometric corrections for population I and II FGKtype stars based on V and 2MASS IR photometry. Accurate calibration isaccomplished by using a sample of solar analogues, whose averagetemperature is assumed to be equal to the solar effective temperature of5777 K. By taking into account all possible sources of error we estimateassociated uncertainties to better than 1% in effective temperature andin the range 1.0-2.5% in angular semi-diameter for unreddened stars.Comparison of our new temperatures with other determinations extractedfrom the literature indicates, in general, remarkably good agreement.These results suggest that the effective temperaure scale of FGK starsis currently established with an accuracy better than 0.5%-1%. Theapplication of the method to a sample of 10 999 dwarfs in the Hipparcoscatalogue allows us to define temperature and bolometric correction (Kband) calibrations as a function of (V-K), [m/H] and log g. Bolometriccorrections in the V and K bands as a function of T_eff, [m/H] and log gare also given. We provide effective temperatures, angularsemi-diameters, radii and bolometric corrections in the V and K bandsfor the 10 999 FGK stars in our sample with the correspondinguncertainties.
| A photoelectric study of three southern Delta Scuti stars
Differential photoelectric observations of three Delta Scuti stars AIScl, WZ Scl, and XX Scl were obtained on ten nights during October 1978.Al Scl did not exhibit strictly periodic behavior, but showed a tendencyto pulsate at 134 minutes. WZ Scl and XX Scl were both found to bemultiperiodic, with period ratios of 0.6853 and 0.9522, respectively. Asthe period for radial fundamental and first overtone pulsation is 0.76,the observed period ratios are interpreted as caused by nonradialpulsation. A slightly modified Jurkevich period search method, used toobtain these results, is described.
|
Sottometti un nuovo articolo
Link relazionati
Sottometti un nuovo link
Membro dei seguenti gruppi:
|
Osservazione e dati astrometrici
| Costellazione: | Scultore |
| Ascensione retta: | 01h12m20.06s |
| Declinazione: | -38°14'51.6" |
| Magnitudine apparente: | 9.072 |
| Moto proprio RA: | 16 |
| Moto proprio Dec: | -14.8 |
| B-T magnitude: | 9.648 |
| V-T magnitude: | 9.12 |
Cataloghi e designazioni:
|
