Star formation in Perseus - V. Outflows detected by HARP - Astrophysics > Astrophysics of GalaxiesReportar como inadecuado

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Abstract: Molecular outflows provide an alternative method of identifying protostellarcores, complementary to recent mid-infrared studies. Continuing our studies ofPerseus, we investigate whether all Spitzer-identified protostars, andparticularly those with low luminosities, drive outflows, and if any newprotostellar cores perhaps harbouring low-mass sources can be identified viatheir outflows alone. We have used the heterodyne array receiver HARP on JCMTto make deep 12CO 3-2 maps of submm cores in Perseus, extending and deepeningour earlier study with RxB and bringing the total number of SCUBA cores studiedup to 83. Our survey includes 23-25 of the Dunham et al. 2008 Spitzerlow-luminosity objects believed to be embedded protostars, including threeVeLLOs. All but one of the cores identified as harbouring embedded YSOs haveoutflows, confirming outflow detections as a good method for identifyingprotostars. We detect outflows from 20 Spitzer low-luminosity objects. We donot conclusively detect any outflows from IR-quiet cores, though confusion inclustered regions such as NGC1333 makes it impossible to identify all theindividual driving sources. This similarity in detection rates despite thedifference in search methods and detection limits suggests either that thesample of protostars in Perseus is now complete, or that the existence of anoutflow contributes to the Spitzer detectability, perhaps through thecontribution of shocked H2 emission in the IRAC bands. For five of thelow-luminosity sources, there is no protostellar envelope detected at 350microns and the Spitzer emission is entirely due to shocks. Additionally, wedetect the outflow from IRAS 03282+3035 at 850 microns with SCUBA due to COline contamination in the continuum passband.

Autor: Jennifer Hatchell, Michael M. Dunham


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