相关论文: Pre-main sequence stars in the Lagoon Nebula (M8)
We report on the properties of the low-mass stars that recently formed in the central ~ 2.7'x2.7' of 30 Dor including the R136 cluster. Using the photometric catalogue of De Marchi et al. (2011c), based on observations with the Hubble Space…
I discuss results from the recent spectroscopic survey for solar-type pre-MS stars in the Lower Centaurus-Crux (LCC) and Upper Centaurus-Lupus (UCL) OB subgroups by Mamajek, Meyer, & Liebert (2002, AJ, 124, 1670). LCC and UCL are subgroups…
We observed a field of $16'\times 16'$ in the star-forming region Pelican Nebula (IC 5070) at $BVRI$ wavelengths for 90 nights spread over one year in 2012-2013. More than 250 epochs in $VRI$-bands are used to identify and classify…
Using the Wide Field Grism Spectrograph 2 (WFGS2), we have carried out slit-less spectroscopy, g'r'i' photometry, and slit spectroscopy on the L1014 dense core. We detected three Halpha emission line stars. We interpret one as weak-line T…
Seven of ten candidate H-alpha emission-line stars found in an objective grism survey of a 1 square degree region in MBM 18, were observed spectroscopically. Four of these have weak H-alpha emission, and 6 out of 7 have spectral types…
We study the accretion properties of pre-main sequence low-mass stars in the LH 91 association within the Large Magellanic Clouds. Using optical multiband photometry obtained with the Hubble Space Telescope, we identify 75 candidates…
The Orion Nebula Cluster and the molecular cloud in its vicinity have been observed with the ACIS-I detector on board the Chandra X-ray Observatory with 23 hours exposure. We detect 1075 X-ray sources: 91% are spatially associated with…
We present the detection of an intermediate-mass pre-main-sequence population embedded in the nebular filaments surrounding the 30 Doradus region in the Large Magellanic Cloud (LMC) using HST/NICMOS. In addition to four previously known…
The results of an optical spectroscopic survey of a sample of young stellar objects (YSOs) and pre-main sequence (PMS) stars in the Lupus Clouds are presented. 92 objects were observed with VLT/FLAMES. All of those objects show IR excess as…
We present results of multi-epoch (fourteen nights during 2007-2010) $V$-band photometry of the cluster NGC 1893 region to identify photometric variable stars in the cluster. The study identified a total of 53 stars showing photometric…
We have analyzed optical spectra of 25 X-ray sources identified as potential new members of the Taurus molecular cloud (TMC), in order to confirm their membership in this SFR. Fifty-seven candidates were previously selected among the X-ray…
We give results of a low-resolution optical spectroscopic study of the bright nebulous stars conforming the tight stellar trapezium embedded in IRAS06548-0815, of the exciting star of IRAS06547-0810, and of the stars associated with…
We have analyzed photometric and spectroscopic data of a sample of 14 spatially resolved pre-main-sequence binaries (separations 0.6" to 1.7") in the nearby (150 pc) low-mass star-forming regions of Chamaeleon, Lupus, and rho Ophiuchi. The…
We present the project we are carrying out at present, the search for and characterisation of pre-main sequence (PMS) stars among the members of Galactic young clusters. The observations of 10 southern clusters, nine of them located in the…
We analyze spectra of 44 emission line stars detected in a low resolution optical spectroscopic survey of the galactic open cluster NGC 6871. The survey of 1217 stars is complete to V = 14.9 and includes stars with V < 16.5 between the zero…
Multiple photometric studies have reported the presence of seemingly older accreting pre-main sequence stars (PMS) in optical colour-magnitude diagrams (CMDs). We investigate this phenomenon in the Orion Nebula, which harbors a subset of…
I have isolated a population of numerous F stars that appear to be pre-main-sequence (PMS). The candidate PMS stars have been identified using CM diagram, reddening, flux excess in the UV and near-infrared, and luminosity anomaly. Negative…
We present a Spitzer InfraRed Spectrometer search for 10-36 micron molecular emission from a large sample of protoplanetary disks, including lines from H2O, OH, C2H2, HCN and CO2. This paper describes the sample and data processing and…
We have measured the present accretion rate of roughly 800 low-mass (~1-1.4 Mo) pre-Main Sequence stars in the field of Supernova 1987A in the Large Magellanic Cloud (LMC, Z~0.3 Zo). It is the first time that this fundamental parameter for…
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…