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Title: L1188: A Promising Candidate for Cloud–Cloud Collisions Triggering the Formation of Low- and Intermediate-mass Stars

Abstract

We present a new large-scale (2° × 2°) simultaneous {sup 12}CO, {sup 13}CO, and C{sup 18}O (J = 1–0) mapping of L1188 with the Purple Mountain Observatory 13.7 m telescope. Our observations have revealed that L1188 consists of two nearly orthogonal filamentary molecular clouds at two clearly separated velocities. Toward the intersection showing large velocity spreads, we find several bridging features connecting the two clouds in velocity, and an open arc structure that exhibits high excitation temperatures, enhanced {sup 12}CO and {sup 13}CO emission, and broad {sup 12}CO line wings. This agrees with the scenario that the two clouds are colliding with each other. The distribution of young stellar object (YSO) candidates implies an enhancement of star formation in the intersection of the two clouds. We suggest that a cloud–cloud collision happened in L1188 about 1 Myr ago, possibly triggering the formation of low- and intermediate-mass YSOs in the intersection.

Authors:
; ; ; ; ; ; ; ; ;  [1]
  1. Purple Mountain Observatory and Key Laboratory of Radio Astronomy, Chinese Academy of Sciences, 2 West Beijing Road, 210008 Nanjing (China)
Publication Date:
OSTI Identifier:
22654569
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 835; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CARBON 12; CARBON 13; CARBON 18; CARBON MONOXIDE; CLOUDS; COLLISIONS; DISTRIBUTION; EMISSION; EXCITATION; MASS; STARS; TELESCOPES; VELOCITY

Citation Formats

Gong, Yan, Fang, Min, Mao, Ruiqing, Zhang, Shaobo, Wang, Yuan, Su, Yang, Chen, Xuepeng, Yang, Ji, Wang, Hongchi, and Lu, Dengrong, E-mail: ygong@pmo.ac.cn. L1188: A Promising Candidate for Cloud–Cloud Collisions Triggering the Formation of Low- and Intermediate-mass Stars. United States: N. p., 2017. Web. doi:10.3847/2041-8213/835/1/L14.
Gong, Yan, Fang, Min, Mao, Ruiqing, Zhang, Shaobo, Wang, Yuan, Su, Yang, Chen, Xuepeng, Yang, Ji, Wang, Hongchi, & Lu, Dengrong, E-mail: ygong@pmo.ac.cn. L1188: A Promising Candidate for Cloud–Cloud Collisions Triggering the Formation of Low- and Intermediate-mass Stars. United States. doi:10.3847/2041-8213/835/1/L14.
Gong, Yan, Fang, Min, Mao, Ruiqing, Zhang, Shaobo, Wang, Yuan, Su, Yang, Chen, Xuepeng, Yang, Ji, Wang, Hongchi, and Lu, Dengrong, E-mail: ygong@pmo.ac.cn. Fri . "L1188: A Promising Candidate for Cloud–Cloud Collisions Triggering the Formation of Low- and Intermediate-mass Stars". United States. doi:10.3847/2041-8213/835/1/L14.
@article{osti_22654569,
title = {L1188: A Promising Candidate for Cloud–Cloud Collisions Triggering the Formation of Low- and Intermediate-mass Stars},
author = {Gong, Yan and Fang, Min and Mao, Ruiqing and Zhang, Shaobo and Wang, Yuan and Su, Yang and Chen, Xuepeng and Yang, Ji and Wang, Hongchi and Lu, Dengrong, E-mail: ygong@pmo.ac.cn},
abstractNote = {We present a new large-scale (2° × 2°) simultaneous {sup 12}CO, {sup 13}CO, and C{sup 18}O (J = 1–0) mapping of L1188 with the Purple Mountain Observatory 13.7 m telescope. Our observations have revealed that L1188 consists of two nearly orthogonal filamentary molecular clouds at two clearly separated velocities. Toward the intersection showing large velocity spreads, we find several bridging features connecting the two clouds in velocity, and an open arc structure that exhibits high excitation temperatures, enhanced {sup 12}CO and {sup 13}CO emission, and broad {sup 12}CO line wings. This agrees with the scenario that the two clouds are colliding with each other. The distribution of young stellar object (YSO) candidates implies an enhancement of star formation in the intersection of the two clouds. We suggest that a cloud–cloud collision happened in L1188 about 1 Myr ago, possibly triggering the formation of low- and intermediate-mass YSOs in the intersection.},
doi = {10.3847/2041-8213/835/1/L14},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 835,
place = {United States},
year = {Fri Jan 20 00:00:00 EST 2017},
month = {Fri Jan 20 00:00:00 EST 2017}
}
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