TY - JOUR
T1 - HST/GHRS observations of the β pictoris system
T2 - Basic parameters and the age of the system
AU - Lanz, Thierry
AU - Heap, Sara R.
AU - Hubeny, Ivan
N1 - Funding Information:
We thank R. L. Kurucz for constructive comments. Support for this work has been provided by NASA through grant number GO-5356.01-93A from the Space Telescope Science Institute, which is operated by AURA, Inc., under contract NAS5-26555.
PY - 1995/7/1
Y1 - 1995/7/1
N2 - We have reevaluated the basic parameters and age of the A5 IV-V star, β Pictoris, making use of new observations obtained by the Goddard High-Resolution Spectrograph aboard the Hubble Space Telescope and using modern methods of atmospheric modeling and spectral synthesis. We derive stellar parameters appropriate to its spectral type (Teff = 8200 ± 150 K, log g = 4.25 ± 0.1) including a normal (solar) metallicity. When dated by comparison with current evolutionary tracks, we find that (1) the star is apparently “underluminous”—a situation we attribute to (gray) extinction by the disk—and (2) the star is either a pre-main-sequence (PMS) star nearing the zero-age main sequence (ZAMS), or it is a main-sequence star older than 0.3 Gyr. Given the apparent youth of the disk as inferred from its high density, we judge the PMS interpretation as most likely.
AB - We have reevaluated the basic parameters and age of the A5 IV-V star, β Pictoris, making use of new observations obtained by the Goddard High-Resolution Spectrograph aboard the Hubble Space Telescope and using modern methods of atmospheric modeling and spectral synthesis. We derive stellar parameters appropriate to its spectral type (Teff = 8200 ± 150 K, log g = 4.25 ± 0.1) including a normal (solar) metallicity. When dated by comparison with current evolutionary tracks, we find that (1) the star is apparently “underluminous”—a situation we attribute to (gray) extinction by the disk—and (2) the star is either a pre-main-sequence (PMS) star nearing the zero-age main sequence (ZAMS), or it is a main-sequence star older than 0.3 Gyr. Given the apparent youth of the disk as inferred from its high density, we judge the PMS interpretation as most likely.
KW - Stars: Early-type
KW - Stars: Evolution
KW - Stars: Fundamental parameters
KW - Stars: Individual (β Pictoris)
KW - Stars: Pre-main-sequence
UR - http://www.scopus.com/inward/record.url?scp=2842590509&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=2842590509&partnerID=8YFLogxK
U2 - 10.1086/309561
DO - 10.1086/309561
M3 - Article
AN - SCOPUS:2842590509
SN - 0004-637X
VL - 447
SP - L41-L44
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 1
ER -