相关论文: Near-IR imaging of T Cha: evidence for scattered-l…
Young circumstellar disks are of prime interest to understand the physical and chemical conditions under which planet formation takes place. Only very few detections of planet candidates within these disks exist, and most of them are…
T CrA is a Herbig Ae-type young star in a complex circumstellar environment; it includes a circumstellar disk, accretion streamers, jets, and outflows. It has long been suspected to be a binary. However, until now, there has been no direct…
We characterize the physical properties of T Chamaeleontis, a transitional T Tauri star showing UX Ori-type variability, and of its associated disc, and probe possible effects of disc clearing processes. Different spectral diagnostics are…
Transitional discs are a class of circumstellar discs around young stars with extensive clearing of dusty material within their inner regions on 10s of au scales. One of the primary candidates for this kind of clearing is the formation of…
(Abridged) Circumstellar disks are believed to be the birthplace of planets and are expected to dissipate on a timescale of a few Myr. The processes responsible for the removal of the dust and gas will strongly modify the radial…
The model of an young star with a protoplanetary disk and a low-mass companion, which is moving on a circular orbit, inclined to the disk plane, is considered. The hydrodynamic models of such a system were calculated by SPH method. It was…
Context. Direct imaging provides a steady flow of newly discovered giant planets and brown dwarf companions. These multi-object systems can provide information about the formation of low-mass companions in wide orbits and/or help us to…
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…
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 low-resolution mid-infrared spectra of nine classical T Tauri stars associated with the Chamaeleon I dark cloud. The data were obtained with the PHOT-S instrument on-board the Infrared Space Observatory (ISO) in the two…
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…
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…
We present high-spatial resolution HST and adaptive optics observations, and high-sensitivity ISO (ISOCAM & ISOPHOT) observations of a sample of X-ray selected weak-line (WTTS) and post (PTTS) T Tauri stars located in the nearby Chamaeleon…
RZ Psc is a young Sun-like star with a bright and warm infrared excess that is occasionally dimmed significantly by circumstellar dust structures. Optical depth arguments suggest that the dimming events do not probe a typical sight line…
RZ Cha is a detached eclipsing binary containing two slightly evolved F5 stars in a circular orbit of period 2.832 d. We use new light curves from the Transiting Exoplanet Survey Satellite (TESS) and spectroscopic orbits from Gaia DR3 to…
We seek to establish the presence and properties of gas in the circumstellar disk orbiting T Cha, a nearby (d~110 pc), relatively evolved (age ~5-7 Myr) yet actively accreting 1.5 Msun T Tauri star. We used the APEX 12 m radiotelescope to…
We have identified several lithium-rich low-mass (0.08<M<0.3 Msun) stars within 5.5 deg of the young open cluster Eta Chamaeleontis, nearly four times the radius of previous search efforts. Of these stars we propose 4 new probable cluster…
Birth environments of young stars have strong imprints on the star itself and their surroundings. We present a detailed analysis of the wealthy circumstellar environment around the young Herbig Ae/Be star TCrA. Our aim is to understand the…
HD 142527 is a well-studied intermediate-mass T Tauri star surrounded by a transitional disk with a large dust cavity, spiral structures, and an accreting low-mass companion. Despite extensive observations, the system's inner regions remain…
Circumstellar disks do not evolve in isolation, as about half of solar-type stars were born in binary or multiple systems. Resolving disks in binary systems provides the opportunity to examine the influence of stellar companions on the…