# L1188: a promising candidate of cloud-cloud collision triggering the formation of the low- and intermediate-mass stars

## TL;DR

This study uses large-scale molecular line observations to identify cloud-cloud collision in L1188, linking it to enhanced star formation and the creation of low- and intermediate-mass young stellar objects.

## Contribution

It provides the first detailed evidence of cloud-cloud collision in L1188 and its role in triggering star formation in this region.

## Key findings

- Identification of two orthogonal filamentary clouds at different velocities.
- Detection of bridging features and high-temperature arc structures indicating collision.
- Enhanced star formation activity at the intersection of the colliding clouds.

## Abstract

We present a new large-scale (4 square degrees) simultaneous $^{12}$CO, $^{13}$CO, and C$^{18}$O ($J$=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 $^{12}$CO and $^{13}$CO emission, and broad $^{12}$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.