The CARMA-NRO Orion Survey : filament formation via collision-induced magnetic reconnection - the stick in Orion A
Abstract
A unique filament is identified in the Herschel maps of the Orion A giant molecular cloud. The filament, which we name the Stick, is ruler-straight and at an early evolutionary stage. Transverse position–velocity diagrams show two velocity components closing in on the Stick. The filament shows consecutive rings/forks in C18O (1−0) channel maps, which is reminiscent of structures generated by magnetic reconnection. We propose that the Stick formed via collision-induced magnetic reconnection (CMR). We use the magnetohydrodynamics code Athena++ to simulate the collision between two diffuse molecular clumps, each carrying an antiparallel magnetic field. The clump collision produces a narrow, straight, dense filament with a factor of >200 increase in density. The production of the dense gas is seven times faster than freefall collapse. The dense filament shows ring/fork-like structures in radiative transfer maps. Cores in the filament are confined by surface magnetic pressure. CMR can be an important dense-gas-producing mechanism in the Galaxy and beyond.
Citation
Kong , S , Ossenkopf-Okada , V , Arce , H G , Bally , J , Sánchez-Monge , Á , McGehee , P , Suri , S , Klessen , R S , Carpenter , J M , Lis , D C , Nakamura , F , Schilke , P , Smith , R J , Mairs , S , Goodman , A & Maureira , M J 2021 , ' The CARMA-NRO Orion Survey : filament formation via collision-induced magnetic reconnection - the stick in Orion A ' , Astrophysical Journal , vol. 906 , no. 2 , 80 . https://doi.org/10.3847/1538-4357/abc687
Publication
Astrophysical Journal
Status
Peer reviewed
ISSN
0004-637XType
Journal article
Description
Funding: European Research Council via the ERC Synergy Grant ECOGAL (grant 855130) (R.S.K.). S. Suri acknowledges support from the European Research Council under the Horizon 2020 Framework Program via the ERC Consolidator Grant CSF-648405. R.J.S. acknowledges funding from an STFC ERF (grant ST/N00485X/1).Collections
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