相关论文: Mapping accretion and its variability in the young…

Stellar accretion plays an important role in the early stages of stellar evolution, particularly in Classical T Tauri Stars (CTTSs). Accretion of a CTTS can be related to different physical parameters such as effective temperature…

The mass accretion rate is the fundamental parameter to understand the process of mass assembly that results in the formation of a low-mass star. This parameter has been largely studied in Classical TTauri stars in star-forming regions with…

Rotation is one of the key stellar parameters which undergo substantial evolution during the stellar lifetime, in particular during the early stages. Stellar rotational periods can be determined on the basis of the periodic modulation of…

Young stars surrounded by disks with very low mass accretion rates are likely in the final stages of inner disk evolution and therefore particularly interesting to study. We present ultraviolet (UV) observations of the ~5-9 Myr old stars…

We study the disk and accretion properties of young stars in the NGC 2068 and NGC 2071 clusters. Using low-resolution optical spectra, we define a membership sample and determine an age for the region of ~2 Myr. Using high-resolution…

While the rate of accretion onto T Tauri stars is predicted to decline with age, objects with strong accretion have been detected up to ages of 10 Myr. We analyze a sample of these old accretors identified by having a significant $U$ band…

We revisit the published analyses of ROSAT X-ray observations of the star forming regions NGC 2264 and Chamaeleon I (~3 and ~5 Myr old respectively) in the light of newly published optical data. At odds with previous results on Chamaeleon I…

NGC 2264 is a young Galactic cluster and the dominant component of the Mon OB1 association lying approximately 760 pc distant within the local spiral arm. The cluster is hierarchically structured, with subclusters of suspected members…

Classical T Tauri stars (cTTs) accrete from their circumstellar disk. The material falls onto the stellar surface, producing an accretion shock, which generates veiling in a star's spectra. In addition, the shock causes a localized…

The process of accretion in classical T Tauri stars (CTTSs) has been observed to vary on different timescales. Studying this variability is vital to understanding a star's evolution and provides insight into the complex processes at work…

The timescale of cluster formation is an essential parameter in order to understand the formation process of star clusters. Pre-main sequence (PMS) stars in nearby young open clusters reveal a large spread in brightness. If the spread were…

The mass-accretion rate, Macc, is a crucial parameter for the study of the evolution of accretion disks around young low-mass stellar objects (YSOs) and for planet formation studies. The Taurus star forming region (SFR) is rich in pre-main…

Interpreting the short-timescale variability of the accreting, young, low-mass stars known as Classical T Tauri stars remains an open task. Month-long, continuous light curves from the Transiting Exoplanet Survey Satellite (\textit{TESS})…

We present results from simultaneous FUV and NUV observations of T-Tauri stars (TTSs) in the Taurus molecular cloud with UVIT/AstroSat. This is the very first UVIT study of TTSs. From the spectral energy distribution of TTSs from FUV to…

We present results from 1078 high resolution spectra of 990 stars in the young open cluster NGC 2264, obtained with the Hectochelle multiobject echelle spectrograph on the 6.5m MMT. We confirm 471 stars as members, based on their radial…

Classical T Tauri stars (CTTSs) accrete matter from the inner edge of their surrounding circumstellar disks. The impact of the accretion material on the stellar atmosphere results in a strong shock, which causes emission from the X-ray to…

Accretion is one of the defining characteristics of classical T Tauri stars, fueled by the presence of a circumstellar disk comprised of dust and gas. Accretion produces a UV and optical excess, while re-radiated emission at the inner edge…

This paper presents optical ($ugri$H$\alpha$)-infrared ($JHK$s,3.6--8.0$\mu$m) photometry, and $Gaia$ astrometry of 55 Classical T-Tauri stars (CTTS) in the star-forming region Sh 2-012, and it's central cluster NGC 6383. The sample was…

This paper presents the results of an U band survey with FORS1/VLT of a large area in the sigma Orionis star-forming region. We combine the U-band photometry with literature data to compute accretion luminosity and mass accretion rates from…

We studied the properties of star formation and the characteristics of young stars in a quiet region located beyond the outskirts of the prominent star-forming cluster NGC 346 in the Small Magellanic Cloud (SMC). Utilising observations from…