Journal Article10.1086/305032
Disk accretion rates for T tauri stars
Erik Gullbring,Lee Hartmann,Cesar Briceno,Cesar Briceno,Cesar Briceno,Nuria Calvet,Nuria Calvet +6 more
TL;DR: In this paper, the authors present new measurements of disk accretion rates for T Tauri stars in the Taurus molecular cloud complex, which are based on intermediate-resolution spectrophotometry from 3200 to 5200 A, and derive the excess hot continuum emission produced by accretion onto the central star.
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Abstract: We present new measurements of disk accretion rates for T Tauri stars in the Taurus molecular cloud complex. Our results are based on intermediate-resolution spectrophotometry from 3200 to 5200 A, which is used to derive the excess hot continuum emission produced by accretion onto the central star. Previous estimates of T Tauri accretion rates in the literature differ by as much as 1 order of magnitude; our measurements agree better with the lowest estimates, and we discuss the problems and systematic effects that led to the previous disagreement. In particular, we note that the stellar photospheric emission from nonaccreting T Tauri stars exhibits color anomalies compared to main-sequence stars; these anomalies make the estimated extinction depend upon the color index used. We argue that the V-R index is a reasonable compromise to match with optically derived spectral types, and that V-I and V-J are much more likely to be biased by cooler companion stars and starspots. We develop a calibration with which approximate mass accretion rates can be derived for T Tauri stars based on broadband photometry and spectral types, which should enable accretion rates to be estimated for large samples with greater ease.
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Citations
Unveiling the Structure of Pre-transitional Disks
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TL;DR: In this paper, the authors investigated the difference between the inner regions of transitional and pre-transitional disks using the same veiling-based technique to extract the near-infrared excess emission above the stellar photosphere.
334
Three-dimensional magnetohydrodynamic simulations of circumbinary accretion disks: disk structures and angular momentum transport
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329
Measuring accretion in young substellar objects: Approaching the planetary mass regime
TL;DR: In this paper, the authors used Hα emission-line profiles taken at Magellan Observatory for a sample of 39 young low-mass stars and brown dwarfs in the Taurus and Chamaeleon I star-forming regions.
327
Measuring the Magnetic Field on the Classical T Tauri Star BP Tauri
TL;DR: In this article, the authors examined several theories that describe how stellar magnetic fields on T T Tauri stars interact with their surrounding accretion disks, and demonstrated that these theories require magnetic field strengths ranging from a few hundred to several thousand gauss, depending on which model is used and more importantly on the properties of individual systems.
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Emission-Line Diagnostics of T Tauri Magnetospheric Accretion. I. Line Profile Observations
TL;DR: In this article, the authors present high-resolution spectra of T Tauri stars in Taurus in the range 5800-9000 A to critically examine the current theories of magnetospheric accretion.
320
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Disk accretion onto magnetic T Tauri stars
TL;DR: In this article, the dynamical and radiative consequences of disk accretion onto magnetic T T Tauri stars (TTS) were examined using the Ghosh and Lamb model, and it was shown that a prolonged disk accuration phase is compatible with the low rotation rates measured in these stars if they possess a kilogauss strength field that disrupts the disk at a distance of a few stellar radii from the center.
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