期刊
ASTROPHYSICAL JOURNAL
卷 729, 期 2, 页码 -出版社
IOP PUBLISHING LTD
DOI: 10.1088/0004-637X/729/2/84
关键词
astrochemistry; infrared: ISM; ISM: individual objects (CB130); stars: formation; stars: low-mass; submillimeter: ISM
资金
- NASA [1224608, 1288664, 1407, NNX07AJ72G, 1279198, 1288806, 1342425]
- NSF [AST-0607793, AST-0708158]
- Korea government (MEST) [2009-0062866]
- Ministry of Education, Science and Technology [2010-0008704]
- Division Of Astronomical Sciences
- Direct For Mathematical & Physical Scien [838261] Funding Source: National Science Foundation
- National Research Foundation of Korea [2010-0008704] Funding Source: Korea Institute of Science & Technology Information (KISTI), National Science & Technology Information Service (NTIS)
We present new observations of the CB130 region composed of three separate cores. Using the Spitzer Space Telescope, we detected a Class 0 and a Class II object in one of these, CB130-1. The observed photometric data from Spitzer and ground-based telescopes are used to establish the physical parameters of the Class 0 object. Spectral energy distribution fitting with a radiative transfer model shows that the luminosity of the Class 0 object is 0.14-0.16 L-circle dot, which is low for a protostellar object. In order to constrain the chemical characteristics of the core having the low-luminosity object, we compare our molecular line observations to models of lines including abundance variations. We tested both ad hoc step function abundance models and a series of self-consistent chemical evolution models. In the chemical evolution models, we consider a continuous accretion model and an episodic accretion model to explore how variable luminosity affects the chemistry. The step function abundance models can match observed lines reasonably well. The best-fitting chemical evolution model requires episodic accretion and the formation of CO2 ice from CO ice during the low-luminosity periods. This process removes C from the gas phase, providing a much improved fit to the observed gas-phase molecular lines and the CO2 ice absorption feature. Based on the chemical model result, the low luminosity of CB130-1 is explained better as a quiescent stage between episodic accretion bursts rather than being at the first hydrostatic core stage.
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