Related papers: Post-T Tauri stars: a false problem
We re-examine critically the estimates of the duration of different phases of star formation and the lifetimes of molecular clouds, based on the ages of T-Tauri stars, age spreads of stars in clusters, and statistics of pre-stellar cores.…
I review the observational challenges of finding post T Tauri stars (PTTS), defined here as low-mass, pre-main-sequence stars with ages of 10^7-10^8 yr. Such stars are difficult to find because they are less active than younger T Tauri…
The remarkably filamentary spatial distribution of young stars in the Taurus molecular cloud has significant implications for understanding low-mass star formation in relatively quiescent conditions. The large scale and regular spacing of…
We discuss problems with some observational estimates indicating long protostellar core lifetimes and large stellar age spreads in molecular clouds. We also point out some additional observational constraints which suggest that protostellar…
It has now been known for over a decade that low-mass stars located in star-forming regions are very frequently members of binary and multiple systems, even more so than main sequence stars in the solar neighborhood. This high multiplicity…
The Taurus molecular cloud complex is the paradigm for quiescent, low-density, isolated star formation. Yet the age distribution of its stellar population indicates that star formation is a rapid and dynamic process, inconsistent with the…
Observations suggest that star formation occurs in only one or two crossing times for a range of scales spanning a factor of 1000. These observations include (1) measurements of embedded cluster ages in comparison with the cloud core…
Current magnetic-accretion models for classical T-Tauri stars rely on a strong, dipolar magnetic field of stellar origin to funnel the disk material onto the star, and assume a steady-state. In this paper, I critically examine the physical…
We investigate the evolution of circumstellar discs around T Tauri stars that are ejected from small stellar clusters within molecular clouds. In particular, we study how the interaction that leads to ejection may hasten the transition…
I review some recent work on low-mass star formation, with an emphasis on theory, basic principles, and unresolved questions. Star formation is both a gravitational fragmentation problem as well as an accretion problem. Molecular cloud…
Low-mass protostars are less luminous than expected. This luminosity problem is important because the observations appear to be inconsistent with some of the basic premises of star formation theory. Two possible solutions are that stars…
To understand the formation of stellar groups, one must first document carefully the birth pattern within real clusters and associations. In this study of Taurus-Auriga, we combine pre-main-sequence ages from our own evolutionary tracks…
It has recently been noted that many discs around T Tauri stars appear to comprise only a few Jupiter-masses of gas and dust. Using millimetre surveys of discs within six local star-formation regions, we confirm this result, and find that…
Medium-resolution optical spectroscopy of the candidate YSOs associated with the small, nearby molecular cloud Lynds~1333 revealed four previously unknown classical T Tauri stars, two of which are components of a visual double, and a Class…
Observations of both star-forming regions and young, gas-free stellar associations indicate that most nearby molecular clouds form stars only over a short time span before dispersal; large-scale flows in the diffuse interstellar medium have…
We present a high spatial resolution UV to NIR survey of 44 young binary stars in Taurus with separations of 10-1000 AU. The primary results include: (1) The relative ages of binary star components are more similar than the relative ages of…
Classical T Tauri stars are low-mass pre-main sequence stars with an active circumstellar environment. In this work we present the identification and study of 260 Classical T Tauri stars using LAMOST Data Release 6, among which 104 stars…
Results of high-cadence multi-colour observations of 121 pre-main sequence stars available from the northern hemisphere are presented. The aim of this survey was to detect transit-like signatures caused by occultation of these young stars…
We investigate the long-term dynamical evolution of two distinct stellar populations of low-mass stars in globular clusters in order to study whether the energy equipartition process can explain the high number of stars harbouring abundance…
We present our diagnosis of the role that massive stars play in the formation of low- and intermediate-mass stars in OB associations (the Lambda Ori region, Ori OB1, and Lac OB1 associations). We find that the classical T Tauri stars and…