相关论文: Spectrophotometric properties of pre-main sequence…

We present a comprehensive investigation of the Epsilon Chamaeleontis association (Epsilon Cha), one of several young moving groups spread across the southern sky. We re-assess the putative membership of Epsilon Cha using the best-available…

We report new results in our continuing study of the unique compact (1 pc extent), nearby (d = 97 pc), young (t = 9 Myr) stellar cluster dominated by the B9 star eta Chamaeleontis. An optical photometric survey spanning 1.3 x 1.3 pc adds…

We present IRS spectra and revised MIPS photometry for the 18 members of the Eta Chamaeleontis cluster. Aged 8 Myr, the Eta Cha cluster is one of the few nearby regions within the 5-10 Myr age range, during which the disk fraction decreases…

Attention is given to a population of 110 stars in the NGC 6611 cluster of the Eagle Nebula that have prominent near-infrared (NIR) excess and optical colours typical of pre-main sequence (PMS) stars older than 8 Myr. At least half of those…

The eta Chamaeleontis star cluster is one of the most important nearby groupings of pre-main sequence (PMS) stars. With accurately known distance, compact structure and highly-coeval intermediate-aged population, the eta Cha cluster is an…

We present the outcomes of a Chandra X-ray Observatory snapshot study of five nearby Herbig Ae/Be (HAeBe) stars which are kinematically linked with the Oph-Sco-Cen Association (OSCA). Optical photometric and spectroscopic followup was…

Protoplanetary discs are the birthplace for planets. Studying protoplanetary discs is the key to constraining theories of planet formation. By observing dust and gas in associations at different ages we can study the evolution of these…

Eta Chamaeleontis is a unique young (~9 Myr) association with 18 systems concentrated in a radius of ~35 arcmin, i.e. 1pc at the cluster distance of 97pc. No other members have been found up to 1.5 degrees from the cluster centre. The…

We report the outcome of the deep optical/infrared photometric survey of the central region (33 X 33 arcmin or 0.9 pc^2) of the eta Chamaeleontis pre-main sequence star cluster. The completeness limits of the photometry are I = 19.1, J =…

We have mapped the eta Chamaeleontis young stellar association in the far-infrared with the Multiband Imaging Photometer for Spitzer (MIPS) on the Spitzer Space Telescope. All sixteen members within the map region were detected at 24 um,…

I present the results of a search for new low-mass stars and brown dwarfs in the Eta Cha and Eps Cha young associations. Within radii of 1.5 and 0.5 deg surrounding Eta Cha and Eps Cha, respectively, I have constructed color-magnitude…

Sensitive X-ray imaging surveys provide a new and effective tool to establish the census of pre-main sequence (PMS) stars in nearby young stellar clusters. We report here a deep Chandra X-ray Observatory observation of PMS stars in the…

A young, nearby compact aggregate of X-ray emitting pre-main sequence stars was recently discovered in the vicinity of eta Cha (B8V). In this paper, we further investigate this cluster: its membership, its environs and origins. ROSAT HRI…

Nearby associations are ideal regions to study coeval samples of protoplanetary and debris disks down to late M-type stars. Those aged 5-10,Myrs, where most of the disk should have already dissipated forming planets, are of particular…

We have carried out a sensitive high-resolution imaging survey of stars in the young (6-8 Myr), nearby (97 pc) compact cluster around eta Chamaeleontis to search for stellar and sub-stellar companions. Given its youth and proximity, any…

(abridge) The nearby young stellar association Epsilon Cha association has an estimated age of 3-5 Myr, making it an ideal laboratory to study the disk dissipation process and provide empirical constraints on the timescale of planet…

We present the results of an optical multi-band survey for low-mass Pre-Main Sequence (PMS) stars and young Brown Dwarfs (BDs) in the Chamaeleon II (Cha II) dark cloud. This survey constitutes the complementary optical data to the c2d…

We present multi-epoch medium-resolution observations of two M4.5 candidate members in the halo of the ~8 Myr Eta Chamaeleontis open cluster. Over six months of observations both stars exhibited variations in their H-alpha line profiles on…

We have identified three faint new members of the eta Chamaeleontis cluster. Spectral types of the new members are estimated to be ~M5 based on their TiO band strengths and broadband colors. With an age of 5-8 Myr for the cluster, masses of…

A limited-area survey of the eta Chamaeleontis cluster has identified 2 new late-type members. The more significant of these is ECHA J0843.3-7905 (= IRAS F08450-7854), a slowly-rotating (P = 12 d) M2 classical T Tauri (CTT) star with a…