Dissecting the Different Components of the Modest Accretion Bursts of the Very Young Protostar HOPS 373

DOI: 
10.3847/1538-4357/ac5632
Publication date: 
08/04/2022
Main author: 
Yoon, Sung-Yong
IAA authors: 
Osorio, Mayra
Authors: 
Yoon, Sung-Yong;Herczeg, Gregory J.;Lee, Jeong-Eun;Lee, Ho-Gyu;Johnstone, Doug;Varricatt, Watson;Tobin, John J.;Contreras Peña, Carlos;Mairs, Steve;Hodapp, Klaus;Manoj, P.;Osorio, Mayra;Megeath, S. Thomas;JCMT Transient Team
Journal: 
The Astrophysical Journal
Refereed: 
Yes
Publication type: 
Article
Volume: 
929
Pages: 
60
Abstract: 
Observed changes in protostellar brightness can be complicated to interpret. In our James Clerk Maxwell Telescope (JCMT) Transient Monitoring Survey, we discovered that a young binary protostar, HOPS 373, is undergoing a modest 30% brightness increase at 850 μm, caused by a factor of 1.8-3.3 enhancement in the accretion rate. The initial burst occurred over a few months, with a sharp rise and then a shallower decay. A second rise occurred soon after the decay, and the source is still bright one year later. The mid-IR emission, the small-scale CO outflow mapped with ALMA, and the location of variable maser emission indicate that the variability is associated with the SW component. The near-IR and NEOWISE W1 and W2 emission is located along the blueshifted CO outflow, spatially offset by ~3 to 4″ from the SW component. The K-band emission imaged by UKIRT shows a compact H<SUB>2</SUB> emission source at the edge of the outflow, with a tail tracing the outflow back to the source. The W1 emission, likely dominated by scattered light, brightens by 0.7 mag, consistent with expectations based on the submillimeter light curve. The signal of continuum variability in K band and W2 is masked by stable H<SUB>2</SUB> emission, as seen in our Gemini/GNIRS spectrum, and perhaps by CO emission. These differences in emission sources complicate IR searches for variability of the youngest protostars.
Database: 
ADS
SCOPUS
URL: 
https://ui.adsabs.harvard.edu/#abs/2022ApJ...929...60Y/abstract
ADS Bibcode: 
2022ApJ...929...60Y
Keywords: 
Stellar jets;Variable stars;Stellar accretion disks;Submillimeter astronomy;Protostars;1607;1761;1579;1647;1302;Astrophysics - Solar and Stellar Astrophysics;Astrophysics - Astrophysics of Galaxies