2022ApJ...938...44G

We present observations of the J = 1 - 0 transition lines of ¹²CO, ¹³CO, and C¹⁸O toward the Galactic region of 153.°60 ≤ l ≤ 156.°50 and 1.°85 ≤ b ≤ 3.°50, using the Purple Mountain Observatory 13.7 m millimeter telescope. Based on the ¹³CO data, one main filament and five subfilaments are found together as a network structure in the velocity interval of [-42.5, -30.0] km s^–1. The kinematic distance of this molecular cloud is estimated to be ∼4.5 kpc. The median length, width, excitation temperature, and line mass of these filaments are ∼49 pc, ∼2.9 pc, ∼8.9 K, and ∼39 M_⊙ pc^–1, respectively. The velocity structures along these filaments exhibit oscillatory patterns, which are likely caused by the fragmentation or accretion process along these filaments. The maximum accretion rate is estimated to be ∼700 M_⊙ pc^–1. A total of ∼162 ¹³CO clumps and ∼103 young stellar objects are identified in this region. Most of the clumps are in gravitationally bound states. Three H II regions (G154.359+2.606, SH2-211, and SH2-212) are found to be located in the apexes of the filaments. Intense star-forming activity is found along the entire filamentary cloud. The observed results may help us to better understand the link between filaments and massive star formation.