X-ray emission from classical T Tauri stars:: accretion shocks and coronae?

被引：73
作者：
Guenther, H. M. [1 ]
Schmitt, J. H. M. M. [1 ]
Robrade, J. [1 ]
Liefke, C. [1 ]
机构：
[1] Univ Hamburg, Hamburger Sternwarte, D-21029 Hamburg, Germany
来源：
ASTRONOMY & ASTROPHYSICS | 2007年 / 466卷 / 03期
关键词：
accretion; accretion disks; methods : numerical; stars : pre-main sequence; stars : late-type; stars : individual : TW Hya; X rays : stars;
D O I：
10.1051/0004-6361:20065669
中图分类号：
P1 [天文学];
学科分类号：
0704 ;
摘要：
Context. Classical T Tauri stars ( CTTS) are surrounded by actively accreting disks. According to current models material falls along the magnetic field lines from the disk with more or less free-fall velocity onto the star, where the plasma heats up and generates X-rays. Aims. We want to quantitatively explain the observed high energy emission and measure the infall parameters from the data. Absolute flux measurements allow to calculate the filling factor and the mass accretion rate. Methods. We use a numerical model of the hot accretion spot and solve the conservation equations. Results. A comparison to data from XMM-Newton and Chandra shows that our model reproduces the main features very well. It yields for TW Hya a filling factor of 0.3% and a mass accretion rate 2 x 10(-10) M-circle dot yr(-1).
引用
收藏
页码：1111 / 1121
页数：11
相关论文
共 65 条
  • [1] Variability of southern T Tauri stars. II. The spectral variability of the classical T Tauri star TW Hydrae
    Alencar, SHP
    Batalha, C
    [J]. ASTROPHYSICAL JOURNAL, 2002, 571 (01) : 378 - 393
  • [2] The limiting effects of dust in brown dwarf model atmospheres
    Allard, F
    Hauschildt, PH
    Alexander, DR
    Tamanai, A
    Schweitzer, A
    [J]. ASTROPHYSICAL JOURNAL, 2001, 556 (01) : 357 - 372
  • [3] XMM-Newton spectroscopy of the metal depleted T Tauri star TWA 5
    Argiroffi, C
    Maggio, A
    Peres, G
    Stelzer, B
    Neuhäuser, R
    [J]. ASTRONOMY & ASTROPHYSICS, 2005, 439 (03) : 1149 - U53
  • [4] Arnaud KA, 1996, ASTR SOC P, V101, P17
  • [5] Arnaud M., 1985, Astronomy & Astrophysics Supplement Series, V60, P425
  • [6] Baraffe I, 1998, ASTRON ASTROPHYS, V337, P403
  • [7] Variability of southern T Tauri stars (VASTT). III. The continuum flux changes of the TW Hydrae bright spot
    Batalha, C
    Batalha, NM
    Alencar, SHP
    Lopes, DF
    Duarte, ES
    [J]. ASTROPHYSICAL JOURNAL, 2002, 580 (01) : 343 - 357
  • [8] Helium emission from classical T Tauri stars: Dual origin in magnetospheric infall and hot wind
    Beristain, G
    Edwards, S
    Kwan, J
    [J]. ASTROPHYSICAL JOURNAL, 2001, 551 (02) : 1037 - 1064
  • [9] XMM-Newton and the Pleiades -: I.: Bright coronal sources and the X-ray emission from intermediate-type stars
    Briggs, KR
    Pye, JP
    [J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2003, 345 (03) : 714 - 726
  • [10] First light measurements with the XMM-Newton reflection grating spectrometers:: Evidence for an inverse first ionisation potential effect and anomalous Ne abundance in the Coronae of HR 1099
    Brinkman, AC
    Behar, E
    Güdel, M
    Audard, M
    den Boggende, AJF
    Branduardi-Raymont, G
    Cottam, J
    Erd, C
    den Herder, JW
    Jansen, F
    Kaastra, JS
    Kahn, SM
    Mewe, R
    Paerels, FBS
    Peterson, JR
    Rasmussen, AP
    Sakelliou, I
    de Vries, C
    [J]. ASTRONOMY & ASTROPHYSICS, 2001, 365 (01) : L324 - L328
1234567