The internal velocity structure within dense gaseous cores plays a crucial role in providing the initial conditions for star formation in molecular clouds. However, the kinematic properties of dense gas at core scales (∼0.01−0.1 pc) has not been extensively characterized because of instrument limitations until the unique capabilities of GBT-Argus became available. The ongoing GBT-Argus Large Program, Dynamics in Star-forming Cores (DiSCo) thus aims to investigate the origin and distribution of angular momentum of star-forming cores. DiSCo will survey all starless cores and Class 0 protostellar cores in the Perseus molecular complex down to ∼0.01 pc scales with <0.05 km s−1 velocity resolution using the dense gas tracer N2H+. Here, we present the first data sets from DiSCo towards the B1 and NGC 1333 regions in Perseus. Our results suggest that a dense core’s internal velocity structure has little correlation with other core-scale properties, indicating these gas motions may be originated externally from cloud-scale turbulence. These first data sets also reaffirm the ability of GBT-Argus for studying dense core velocity structure and provided an empirical basis for future studies that address the angular momentum problem with a statistically broad sample.
This content will become publicly available on January 1, 2025
- NSF-PAR ID:
- 10526694
- Publisher / Repository:
- Astronomy & Astrophysics
- Date Published:
- Journal Name:
- Astronomy & Astrophysics
- Volume:
- 681
- ISSN:
- 0004-6361
- Page Range / eLocation ID:
- A51
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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