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arXiv · 1205.3732

Measuring the mass accretion rates of Herbig Ae/Be stars with X-shooter

M. A. Pogodin·S. Hubrig·R. V. Yudin·M. Schoeller·J. F. Gonzalez·B. Stelzer
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Abstract

We present the results of our observations of eight magnetic Herbig Ae/Be stars obtained with the X-shooter spectrograph mounted on UT2 at the VLT. X-shooter provides a simultaneous, medium-resolution and high-sensitivity spectrum over the entire wavelength range from 300 to 2500 nm. We estimate the mass accretion rates M_acc of the targets from 13 different spectral diagnostics using empiric calibrations derived previously for T Tauri-type stars and brown dwarfs. We have estimated the mass accretion rates of our targets, which range from 2x10^-9 to 2x10^-7 M_sun/yr. Furthermore, we have found accretion rate variability with amplitudes of 0.10-0.40 dex taking place on time scales from one day to tens of days. Additional future night-to-night observations need to be carried out to investigate the character of M_acc variability in details. Our study shows that the majority of the calibrational relations can be applied to Herbig Ae/Be stars, but several of them need to be re-calibrated on the basis of new spectral data for a larger number of Herbig Ae/Be stars.

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M. A. Pogodin, S. Hubrig, R. V. Yudin, M. Schoeller, J. F. Gonzalez, B. Stelzer. 2012-05-16. Measuring the mass accretion rates of Herbig Ae/Be stars with X-shooter. https://doi.org/10.1002/asna.201211706

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