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Using CO (J=1–0) molecular line data obtained from the 13.7-meter millimeter-wave telescope at the Purple Mountain Observatory's Delingha Observatory, Sun Mingke, a Ph.D. student from the Xinjiang Astronomical Observatory of the Chinese Academy of Sciences and his collaborators conducted a systematic study of the galactic molecular cloud G34. They revealed the collisional signatures and dynamical mechanisms of filamentary structures in this region. The results are in Astronomy & Astrophysics.

Star formation is one of the key processes that drive the evolution of galaxies and the interstellar medium. Recent observations and theoretical studies suggest that interactions and collisions between large-scale filamentary structures may play an important role in triggering high-mass star formation.

In this study, the researchers identified two giant filaments, designated F1 and F2, in the G34 region. By analyzing their spatial distribution and velocity field, the researchers found clear evidence of ongoing collisions between the filaments.

The fractions of high-column-density gas (N(H₂)&²µ³Ù;1.0×10²²cm^-2) within F1 and F2 are relatively low, only 4.16% and 8.33%, respectively. Across the entire region, only one dense clump is spatially associated with a WISE 22 μm infrared dust core. These findings suggest that F1 and F2 are in the early evolutionary stage and are currently forming low-mass stars.

In addition, both the velocity and line mass of the filaments increase gradually from their ends toward the center, in an anti-correlation with the gravitational potential. This indicates that gravitational potential energy is being converted into kinetic energy, highlighting the importance of gravity in filament evolution.

Furthermore, no H II regions were found to be associated with F1 and F2, implying that these large-scale structures are not yet influenced by stellar feedback from ionized regions. Instead, their dynamics are primarily governed by self-gravity, which further supports the scenario that filament collision is a key mechanism driving the evolution of the system.

This study not only provides new observational evidence for the formation and evolution of filamentary structures but also highlights the important role of gravitationally driven processes in shaping their dynamics. The results contribute to a deeper understanding of the early evolutionary mechanisms of giant filamentary structures in the Milky Way.