Contenuti
Immagini
Carica la tua immagine
DSS Images Other Images
Articoli relazionati
Confirmation among visual multiples of an increase of AP stars with age
Open clusters with ages below certain threshold values contain no Apstars and those with greater ages contain numbers of Ap stars thatapparently increase with age. But in view of the few young clustersstudied, the data could also be interpreted in terms of randomdifferences in the frequencies of Ap stars between individual clusters,rather than an age effect. Data on 77 field visual multiple systems(that originated from many different clusters and associations) in whichthe primaries are O5-A1 stars and the secondaries occur in the absolutemagnitude range of the Ap stars were, therefore, obtained. Againspectral classification shows no Ap stars in systems with ages notgreater than 1,000,000 yr and a steady increase in Ap stars thereafter.The numerical agreement with the cluster data is good, confirming thatthe cluster data are exhibiting a real age effect.
|
Sottometti un nuovo articolo
Link relazionati
Sottometti un nuovo link
Membro dei seguenti gruppi:
|
Osservazione e dati astrometrici
| Costellazione: | Serpente |
| Ascensione retta: | 18h42m53.31s |
| Declinazione: | +05°44'27.9" |
| Magnitudine apparente: | 9.137 |
| Moto proprio RA: | -2.5 |
| Moto proprio Dec: | -9 |
| B-T magnitude: | 9.301 |
| V-T magnitude: | 9.151 |
Cataloghi e designazioni:
|
