Large-scale CO J=1-0 observations of the giant molecular cloud
  associated with the infrared ring N35 with the Nobeyama 45-m telescope
  We report an observational study of the giant molecular cloud (GMC)
associated with the Galactic infrared ring-like structure N35 and two nearby
HII regions G024.392+00.072 (HII region A) and G024.510-00.060 (HII region B),
using the new CO J=1-0 data obtained as a part of the FOREST Unbiased Galactic
Plane Imaging survey with the Nobeyama 45-m telescope (FUGIN) project at a
spatial resolution of 21". Our CO data revealed that the GMC, with a total
molecular mass of 2.1x10^6Mo, has two velocity components over ~10-15km/s. The
majority of molecular gas in the GMC is included in the lower-velocity
component (LVC) at ~110-114km/s, while the higher-velocity components (HVCs) at
~118-126km/s consist of three smaller molecular clouds which are located near
the three HII regions. The LVC and HVCs show spatially complementary
distributions along the line-of-sight, despite large velocity separations of
~5-15km/s, and are connected in velocity by the CO emission with intermediate
intensities. By comparing the observations with simulations, we discuss a
scenario where collisions of the three HVCs with LVC at velocities of
~10-15km/s can provide an interpretation of these two observational signatures.
The intermediate velocity features between the LVC and HVCs can be understood
as broad bridge features, which indicate the turbulent motion of the gas at the
collision interfaces, while the spatially complementary distributions represent
the cavities created in the LVC by the HVCs through the collisions. Our model
indicates that the three HII regions were formed after the onset of the
collisions, and it is therefore suggested that the high-mass star formation in
the GMC was triggered by the collisions.
