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Arxiv: Investigating Protostellar Accretion-Driven Outflows Across the Mass Spectrum: JWST NIRSpec IFU 3-5~μm Spectral Mapping of Five Young Protostars Published: 10/5/2023 9:00:05 PM Updated: 4/24/2024 5:59:22 PM

Paper abstract: Investigating Protostellar Accretion is a Cycle 1 JWST program using theNIRSpec+MIRI integral field units to obtain 2.9--28 \mum spectral cubes offive young protostars with luminosities of 0.2-10,000 L_{\odot} in theirprimary accretion phase. This paper introduces the NIRSpec 2.9--5.3 \mum dataof the inner 840-9000 au with spatial resolutions from 28-300 au. The spectrashow rising continuum emission; deep ice absorption; emission from H_{2},H~I, and [Fe~II]; and the CO fundamental series in emission and absorption.Maps of the continuum emission show scattered light cavities for all fiveprotostars. In the cavities, collimated jets are detected in [Fe~II] for thefour < 320~L_{\odot} protostars, two of which are additionally traced inBr-\alpha. Knots of [Fe~II] emission are detected toward the most luminousprotostar, and knots of [FeII] emission with dynamical times of < 30~yrs arefound in the jets of the others. While only one jet is traced in H_2, knotsof H_2 and CO are detected in the jets of four protostars. H_2 is seenextending through the cavities, showing that they are filled by warm moleculargas. Bright H_2 emission is seen along the walls of a single cavity, while inthree cavities narrow shells of H_2 emission are found, one of which has an[Fe~II] knot at its apex. These data show cavities containing collimated jetstraced in atomic/ionic gas surrounded by warm molecular gas in a wide-anglewind and/or gas accelerated by bow shocks in the jets.