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تسجيل مستخدم جديدFormation of the Young Massive Cluster R136 triggered by Tidally-driven Colliding HI Flows
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Understanding of massive cluster formation is one of the important issues of astronomy. By analyzing the HI data, we have identified that the two HI velocity components (L- and D-components) are colliding toward the HI Ridge, in the southeastern end of the LMC, which hosts the young massive cluster R136 and $sim$400 O/WR stars (Doran et al. 2013) including the progenitor of SN1987A. The collision is possibly evidenced by bridge features connecting the two HI components and complementary distributions between them. We frame a hypothesis that the collision triggered the formation of R136 and the surrounding high-mass stars as well as the HI & Molecular Ridge. Fujimoto & Noguchi (1990) advocated that the last tidal interaction between the LMC and the SMC about 0.2 Gyr ago induced collision of the L- and D-components. This model is consistent with numerical simulations (Bekki & Chiba 2007b). We suggest that a dense HI partly CO cloud of 10$^{6}$ $M_{odot}$, a precursor of R136, was formed at the shock-compressed interface between the colliding L- and D-components. We suggest that part of the low-metalicity gas from the SMC was mixed in the tidal interaction based on the $Planck/IRAS$ data of dust optical depth (Planck Collaboration et al. 2014).
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