FRAGMENTATION AT THE EARLIEST PHASE OF MASSIVE STAR FORMATION

By Qizhou Zhang, Yang Wang, T. Pillai, J. Rathborne. 2009

152 citations recorded by the source corpus.

We present 1.3 mm continuum and spectral line images of two massive molecular clumps P1 and P2 in the G28.34+0.06 region with the Submillimeter Array (SMA). While the two clumps contain masses of 1000 and 880 M☉, respectively, P1 has a luminosity OF <102 L☉, and a lower gas temperature and smaller line width than P2. Thus, P1 appears to be at a much earlier stage of massive star formation than P2. The high-resolution SMA observations reveal two distinctive cores in P2 with masses of 97 and 49 M☉, respectively. The 4 GHz spectral bandpass captures line emission from CO isotopologues, SO, CH3OH, and CH3CN, similar to hot molecular cores harboring massive young stars. The P1 clump, on the other hand, is resolved into five cores along the filament with masses from 22 to 64 M☉ and an average projected separation of 0.19 pc. Except 12CO, no molecular line emission is detected toward the P1 cores at a 1σ rms of 0.1 K. Since strong 12CO and C18O emissions are seen with the single-dish telescope at a resolution of 11″, the nondetection of these lines with the SMA indicates a depletion factor up to 103. While the spatial resolution of the SMA is better than the expected Jeans length, the masses in P1 cores are much larger than the thermal Jeans mass, indicating the importance of turbulence and/or magnetic fields in cloud fragmentation. The hierarchical structures in the P1 region provide a glimpse of the initial phase of massive star and cluster formation.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/56082687ac9d52434f9797633430ab86013839c4

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. T. Pillai
2. Th. Henning
3. L. Testi
4. Qizhou Zhang
5. S. Finn
6. G. Garay
7. J. Foster
8. P. Sanhueza

In Instrumentation

1. T. Pillai
2. Qizhou Zhang
3. J. Jackson
4. S. Finn
5. Ian A. Bonnell
6. Th. Henning
7. Rowan J. Smith
8. S. Longmore

Citations in the corpus

• EVOLUTION OF MASSIVE PROTOSTARS VIA DISK ACCRETION (2010, unknown): “The proposed formation scenarios are being assessed with high-resolution observations of the massive cores and clumps (e.g., Motte et al. 2007; Marseille et al. 2008; Zhang et al. 2009; Bentemps et al. 2010).”
• The simultaneous formation of massive stars and stellar clusters (2009, result): “2, we interpolate our simulated data (including all material along the column) to a 2D grid of 66 × 66 grid cells, with a spatial resolution of 0.03 pc, comparable to recent observations (e.g. Zhang et al. 2009; Longmore, in preparation).”
• Hierarchical fragmentation and differential star formation in the Galactic ‘Snake’: infrared dark cloud G11.11−0.12 (2014, methodology): “All features above5σ rms are identified as in Wang et al. (2011) and Zhang et al. (2009).”
• CHEMISTRY IN INFRARED DARK CLOUD CLUMPS: A MOLECULAR LINE SURVEY AT 3 mm (2011, background): “Indeed, high angular resolution observations made with interferometers show the clumpy nature of IRDCs (e.g., Rathborne et al. 2007, 2008; Zhang et al. 2009).”