EPoS Contribution

High-order multiplicity formation in high-mass stellar protocluster Shanghuo Li MPIA, Heidelberg, DE
High-mass stars in the Milky Way are overwhelmingly (>80%) found in binaries or higher-order multiplicity systems that play a key role in governing cluster dynamics and stellar evolution. However, the dominant mechanism forming multiple stellar systems in the high-mass regime (M_* ≳ 8 M_⊙) remained unknown because direct imaging of multiple protostellar systems at early phases of high-mass star formation is very challenging. Here we report the discovery of one quintuple, one quadruple, one triple and four binary protostellar systems simultaneously forming in a single high-mass protocluster, G333.23–0.06. This provides the most clear direct measurement of the initial configuration of primordial high-order multiple systems, with implications for the in situ multiplicity and its origin.

Caption: Continuum images of ATCA (3.3 mm), ALMA low-resolution (1.3 mm) and ALMA high-resolution (1.3 mm) observations toward G333.23–0.06.
Collaborators: P. Sanhueza, NAOJ, JP H. Beuther, MPIA, DE H.-R. V. Chen, NTHU, TW R. Kuiper, UDuisburg-Essen, DE F. A. Olguin, NTHU, TW R. E. Pudritz, McMasterU, CA I. W. Stephens, WorcesterSU, US Q. Zhang, CfA, US F. Nakamura, NAOJ, JP X. Lu, SHAO, CN R. L. Kuruwita, HITS, DE T. Sakai, UE-C, JP Th. Henning, MPIA, DE K. Taniguchi, NAOJ, JP F. Li, NanjingU, CN	Key publication Relevant topic(s): Binarity Fragmentation High-Mass SF
Relevant Big Question: How do binary and higher-order multiple system form in the protocluster?