* Astronomy

Title: L1188: a promising candidate of cloud-cloud collision triggering the formation of the low- and intermediate-mass stars
Author: Yan Gong, Min Fang, Ruiqing Mao, Shaobo Zhang, Yuan Wang, Yang Su, Xuepeng Chen, Ji Yang, Hongchi Wang, Dengrong Lu

We present a new large-scale (4 square degrees) simultaneous 12CO, 13CO, and C18O (J=1-0) mapping of L1188 with the PMO 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 which exhibits high excitation temperatures, enhanced 12CO and 13CO emission, and broad 12CO 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.

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