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Arxiv: Uncovering the hidden physical structures and protostellar activities in the Low-Metallicity S284-RE region: results from ALMA and JWST Published: 12/29/2024 8:08:07 AM Updated: 12/29/2024 8:08:07 AM

Paper abstract: We present an observational study of the S284-RE region, a low-metallicityarea associated with the extended S284 HII region. A thermally supercriticalfilament (mass ~2402 M_{\odot}, length ~8.5 pc) is investigatedusing the Herschel column density map. The Spitzer ratio 4.5 \mum/3.6 \mummap traces the H_{2} outflows in this filament, where previously reportedyoung stellar objects (YSOs) are spatially distributed. Analysis of the YSOdistribution has revealed three active star-forming clusters (YCl1, YCl2, YCl3)within the filament. YCl3 seems to be the most evolved, YCl2 the youngest,while YCl1 displays signs of non-thermal fragmentation. The JWST(F470N+F444W)/F356W ratio map reveals at least seven bipolar H_{2} outflows,with four (olc1--olc4) in YCl1 and three (ol1--ol3) in YCl2. The drivingsources of these outflows are identified based on outflow geometry, ALMAcontinuum peaks, and YSO positions. Two ALMA continuum sources, #2 and #3, fromthe M-R_{\rm eff} plot are recognized as potential massive star formationcandidates. The ALMA continuum source #2 hosts at least three outflow-drivingsources, whereas the ALMA continuum source #3 contains two. The bipolar outflowolc1, driven by an embedded object within the continuum source #2, is likely amassive protostar, as indicated by Br-\alpha and PAH emissions depicted inthe JWST (F405N+F444W)/F356W ratio map. The presence of H_{2} knots in theoutflows olc1 and ol1 suggests episodic accretion. Overall, the studyinvestigates a massive protostar candidate, driving the ~2.7 pc H_{2}outflow olc1 and undergoing episodic accretion.