A SLOWLY ACCRETING ∼10 Myr-OLD TRANSITIONAL DISK IN ORION OB1a

被引：37

作者：

Espaillat, C. ^{[1
]}

Muzerolle, J. ^{[2
]}

Hernandez, J. ^{[1
,3
]}

Briceno, C. ^{[3
]}

Calvet, N. ^{[1
]}

D'Alessio, P. ^{[4
]}

McClure, M. ^{[5
]}

Watson, D. M. ^{[5
]}

Hartmann, L. ^{[1
]}

Sargent, B. ^{[5
]}

机构：

[1] Univ Michigan, Dept Astron, Ann Arbor, MI 48109 USA

[2] Univ Arizona, Steward Observ, Tucson, AZ 85712 USA

[3] CIDA, Merida 5101A, Venezuela

[4] Univ Nacl Autonoma Mexico, Ctr Radioastron & Astrofis, Morelia 58089, Michoacan, Mexico

[5] Univ Rochester, Dept Phys & Astron, Rochester, NY 14627 USA

来源：

ASTROPHYSICAL JOURNAL LETTERS | 2008年 / 689卷 / 02期

关键词：

accretion; accretion disks; circumstellar matter; stars: formation; stars: pre-main-sequence;

D O I：

10.1086/595869

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Here we present the Spitzer IRS spectrum of CVSO 224, the sole transitional disk located within the similar to 10 Myr old 25 Orionis group in Orion OB1a. A model fit to the spectral energy distribution of this object indicates a similar to 7 AU inner disk hole that contains a small amount of optically thin dust. In previous studies, CVSO 224 had been classified as a weak-line T Tauri star based on its H alpha equivalent width, but here we find an accretion rate of 7 x 10(-11) M-circle dot yr(-1) based on high-resolution Hectochelle data. CVSO 224's low M is in line with photoe-vaporative clearing theories. However, the Spitzer IRS spectrum of CVSO 224 has a substantial mid-infrared excess beyond 20 mu m which indicates that it is surrounded by a massive outer disk. Millimeter measurements are necessary to constrain the mass of the outer disk around CVSO 224 in order to confirm that photoevaporation is not the mechanism behind creating its inner disk hole.

引用

页码：L145 / L148

页数：4

共 45 条

[1] Dust dynamics during protoplanetary disc clearing [J].