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2007
Herbig Ae/Be stars are the early-type pre-main sequence stars. Normally they are simply abbreviated as HES (Herbig emission-line stars) or HAEBE (Herbig Ae Be stars). (1960) originally defined HES by the following characteristics: (i) The spectral type is A or earlier, with emission lines. (ii) The star lies in an obscured region.
Tomokazu Kogure, Kam-Ching Leung
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Herbig Ae/Be stars are the early-type pre-main sequence stars. Normally they are simply abbreviated as HES (Herbig emission-line stars) or HAEBE (Herbig Ae Be stars). (1960) originally defined HES by the following characteristics: (i) The spectral type is A or earlier, with emission lines. (ii) The star lies in an obscured region.
Tomokazu Kogure, Kam-Ching Leung
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δ Scuti Pulsations in Pre-Main Sequence Stars
Astrophysics and Space Science, 2003Intermediate mass pre-main sequence stars (1.5 to 5 M ⊙) cross the instability strip on their way to the main sequence. They are therefore expected to be pulsating in a similar way as the δ Scuti stars. In this review, I present the status of observational studies of pulsations in these stars, and comment on prospects for future investigations of these
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Chromospheric activities of pre-main-sequence stars
Proceedings of the International Astronomical Union, 2023AbstractWe investigated chromospheric activities of pre-main-sequence (PMS) stars. First, we studied the Ca II infrared triplet emission lines with Subaru/HDS and other spectroscopic instruments. Most PMS stars have narrow Ca II lines whose intensities are as large as the maximum of the zero-age main-sequence (ZAMS) stars. The chromosphere of PMS stars
Mai Yamashita +3 more
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Hipparcos observations of pre-main-sequence stars
Monthly Notices of the Royal Astronomical Society, 1998We present first results of Hipparcos observations of nearby low-mass pre-main-sequence (PMS) stars (T Tauri and Herbig Ae/Be stars). The data obtained by Hipparcos allow us to derive weighted mean parallaxes for three major nearby star-forming regions (SFRs), Lupus, Chamaeleon I and Taurus–Auriga.
R. Wichmann +4 more
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Pre-main-sequence variable stars
2007In section 2.19, we outlined what was presently known about star formation, and the early evolution of stars. There are several types of variability which are specifically or predominantly found among young stars. Most or all of these would be found in a given star, such as the sun, at various times in its pre-main-sequence (PMS) lifetime.
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Pre-Main-Sequence Stages of Stars
Publications of the Astronomical Society of Japan, 1965Abstract Evolutionary model sequences of gravitationally contracting stars were calculated for masses, 0.4, 0.6, 1.0, 1.5, 2.0 and 3.0 M⊙, by using the surface condition based on the conventional mixing length theory of convection and assuming the contraction to be homologous. The mixing length was assumed to be equal to 1-pressure scale
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Asteroseismology of pre-main sequence stars
2008More than 30 years ago the first pulsating pre-main sequence (PMS) stars have been discov- ered. Since then, pulsations in 18 Herbig Ae stars and 18 members of young open clusters were detected and detailed asteroseismic investigations were conducted for some of them. We describe our latest results in this field.
Zwintz, Konstanze +2 more
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PHOTOMETRIC VARIABILITY OF PRE-MAIN SEQUENCE STARS
BOOK OF ABSTRACTS: XIV Serbian-Bulgarian Astronomical ConferenceFor several decades we have been performing photometric monitoring of some of the star formation regions. A significant part of our program is focused on young variable stars, such as FU Orionis, EX Lupi and UX Orionis objects. These three types of young variable stars show changes in brightness with large amplitudes and attract the attention of star ...
Evgeni Semkov +3 more
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Disk accretion in pre-main sequence stars
AIP Conference Proceedings, 1998This paper provides an overview of the observations which support the presence of accretion in disks around pre-main sequence stars and of the characteristics of accretion inferred from their interpretation. The main properties of outbursting, high mass accretion disks, the FU Orionis objects, are summarized. Accretion in the Classical T Tauri stars is
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The Evolution of Pre-Main-Sequence Stars
1999The location of optically visible Pre-Main-Sequence (PMS) stars in the H-R diagram combined with the use of theoretical evolutionary tracks have played a central role in stellar evolution studies since the initial work of Hayashi, Cameron and Iben in the early ′60s.
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