期刊
ASTROPHYSICAL JOURNAL
卷 722, 期 2, 页码 1607-1623出版社
IOP PUBLISHING LTD
DOI: 10.1088/0004-637X/722/2/1607
关键词
astrochemistry; ISM: molecules; protoplanetary disks; stars: formation
资金
- DEL
- JSPS
- JGC-S Scholarship Foundation
- MEXT, Japan
- STFC
- [21740137]
- Grants-in-Aid for Scientific Research [21740137] Funding Source: KAKEN
- Science and Technology Facilities Council [ST/F002270/1] Funding Source: researchfish
- STFC [ST/F002270/1] Funding Source: UKRI
We have developed a high-resolution combined physical and chemical model of a protoplanetary disk surrounding a typical T Tauri star. Our aims were to use our model to calculate the chemical structure of disks on small scales (submilliarcsecond in the inner disk for objects at the distance of Taurus, similar to 140 pc) to investigate the various chemical processes thought to be important in disks and to determine potential molecular tracers of each process. Our gas-phase network was extracted from the UMIST Database for Astrochemistry to which we added gas-grain interactions including freezeout and thermal and non-thermal desorption (cosmic-ray-induced desorption, photodesorption, and X-ray desorption), and a grain-surface network. We find that cosmic-ray-induced desorption has the least effect on our disk chemical structure while photodesorption has a significant effect, enhancing the abundances of most gas-phase molecules throughout the disk and affecting the abundances and distribution of HCN, CN, and CS, in particular. In the outer disk, we also see enhancements in the abundances of H(2)O and CO(2). X-ray desorption is a potentially powerful mechanism in disks, acting to homogenize the fractional abundances of gas-phase species across the depth and increasing the column densities of most molecules, although there remain significant uncertainties in the rates adopted for this process. The addition of grain-surface chemistry enhances the fractional abundances of several small complex organic molecules including CH(3)OH, HCOOCH(3), and CH(3)OCH(3) to potentially observable values (i.e., a fractional abundance of greater than or similar to 10(-11)).
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据