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Arxiv: Characterising the multiple protostellar system VLA 1623-2417 with JWST, ALMA and VLA: outflow origins, dust growth and an unsettled disk Published: 1/30/2025 3:52:21 PM Updated: 1/30/2025 3:52:21 PM

Paper abstract: Utilising JWST, ALMA and the VLA we present high angular resolution (0.06''-0.42''), multi-wavelength (4 micron - 3cm) observations of the VLA 1623-2417protostellar system to characterise the origin, morphology and, properties ofthe continuum emission. JWST observations at 4.4 micron reveal outflow cavitiesfor VLA 1623 A and, for the first time, VLA 1623 B, as well as scattered lightfrom the upper layers of the VLA 1623 W disk. We model themillimetre-centimetre spectral energy distributions to quantify the relativecontributions of dust and ionised gas emission, calculate dust masses, and usespectral index maps to determine where optical depth hinders this analysis. Ingeneral, all objects appear to be optically thick down to ~90 GHz, showevidence for significant amounts (10's - 100's M_Earth) of large (>1 mm) dustgrains, and are dominated by ionised gas emission for frequencies ~<15 GHz. Inaddition, we find evidence of unsettled millimetre dust in the inclined disk ofVLA 1623 B possibly attributed to instabilities within the circumstellar disk,adding to the growing catalogue of unsettled Class 0/I disks. Our resultsrepresent some of the highest resolution observations possible with currentinstrumentation, particularly in the case of the VLA. However, ourinterpretation is still limited at low frequencies (~<22 GHz) and thusmotivates the need for next-generation interferometers operating at centimetrewavelengths.