ALMA observations of massive clouds in the central molecular zone: slim filaments tracing parsec-scale shocks
arXiv:2502.03913 · doi:10.1051/0004-6361/202453191
Abstract
The central molecular zone (CMZ) of our Galaxy exhibits widespread emission from SiO and various complex organic molecules (COMs), yet the exact origin of such emission is uncertain. Here we report the discovery of a unique class of long (0.5 pc) and narrow (0.03 pc) filaments in the emission of SiO 54 and eight additional molecular lines, including several COMs, in our ALMA 1.3 mm spectral line observations toward two massive molecular clouds in the CMZ, which we name as slim filaments. However, these filaments are not detected in the 1.3 mm continuum at the 5 level. Their line-of-sight velocities are coherent and inconsistent with being outflows. The column densities and relative abundances of the detected molecules are statistically similar to those in protostellar outflows but different from those in dense cores within the same clouds. Turbulent pressure in these filaments dominates over self gravity and leads to hydrostatic inequilibrium, indicating that they are a different class of objects than the dense gas filaments in dynamical equilibrium ubiquitously found in nearby molecular clouds. We argue that these newly detected slim filaments are associated with parsec-scale shocks, likely arising from dynamic interactions between shock waves and molecular clouds. The dissipation of the slim filaments may replenish SiO and COMs in the interstellar medium and lead to their widespread emission in the CMZ.
14 pages, 9 figures, 2 tables
References in corpus (26)
- CASA, the Common Astronomy Software Applications for Radio Astronomy
- Trigonometric Parallaxes Of High-Mass Star Forming Regions: Our View Of The Milky Way
- MAMBO Mapping of Spitzer c2d Small Clouds and Cores
- The Critical Density and the Effective Excitation Density of Commonly Observed Molecular Dense Gas Tracers
- The earliest phases of high-mass star formation: a 3 square degree millimeter continuum mapping of Cygnus X
- The largest oxigen bearing organic molecule repository
- Spatial distribution of interstellar gas in the innermost 3 kpc of our Galaxy
- The 1.28 GHz MeerKAT Galactic Center Mosaic
- The Survey of Water and Ammonia in the Galactic Center (SWAG): Molecular Cloud Evolution in the Central Molecular Zone
- The dynamical evolution of molecular clouds near the Galactic Centre - II. Spatial structure and kinematics of simulated clouds
- SiO emission from low- and high-velocity shocks in Cygnus-X massive dense clumps
- Tracing extended low-velocity shocks through SiO emission - Case study of the W43-MM1 ridge
- Star Formation Rates of Massive Molecular Clouds in the Central Molecular Zone
- ALMA Observations of Massive Clouds in the Central Molecular Zone: Jeans Fragmentation and Cluster Formation
- High Resolution Imaging of Molecular Outflows in Massive Young Stars
- On the typical width of Herschel filaments
- ALMA Observations of Massive Clouds in the Central Molecular Zone: Ubiquitous Protostellar Outflows
- Temperature structures in Galactic Center clouds - Direct evidence for gas heating via turbulence
- A train of shocks at 3000 au scale? Exploring the clash of an expanding bubble into the NGC 1333 IRAS 4 region. SOLIS XIV
- SOFIA/HAWC+ Far-Infrared Polarimetric Large-Area CMZ Exploration (FIREPLACE) Survey III: Full Survey Data Set
- Absorption Filaments Towards the Massive Clump G0.253+0.016
- A Large--Scale Spectroscopic Survey of Methanol and OH Line Emission from the Galactic Center: Observations and Data
- ALMA uncovers highly filamentary structure towards the Sgr E region
- A wind-blown bubble in the Central Molecular Zone cloud G0.253+0.016
- OMC-2 FIR 4 under the microscope: Shocks, filaments, and a highly collimated jet at 100 au scales
- Surveys of clumps, cores, and condensations in Cygnus-X: SMA observations of SiO (54)