Infrared and Radio observations of a small group of protostellar objects in the molecular core, L1251-C

  • Kim, Jungha (School of Space Research, Kyung Hee University) ;
  • Lee, Jeong-Eun (School of Space Research, Kyung Hee University) ;
  • Choi, Minho (Korea Astronomy and Space Science Institute) ;
  • Bourke, Tyler L. (Square Kilometre Array Organisation, Jodrell Bank Observatory) ;
  • Evans II, Neal J. (Department of Astronomy, University of Texas at Austin) ;
  • Di Francesco, James (National Research Council Canada, Herzberg Institute of Astrophysics) ;
  • Cieza, Lucas A. (Institute for Astronomy, University of Hawaii at Manoa) ;
  • Dunham, Michael M. (Harvard-Smithsonian Center for Astrophysics)
  • Published : 2015.04.10

Abstract

We present a multi-wavelength observational study of a low-mass star-forming region, L1251-C, with observational results at wavelengths from the near-infrared to the millimeter. Spitzer Space Telescope observations confirmed that IRAS 22343+7501 is a small group of protostellar objects. The extended emission to east-west direction with its intensity peak at the center of L1251A has been detected at 350 and 850 mm with the CSO and JCMT telescopes, tracing dense envelope materials around L1251A. The single-dish data from the KVN and TRAO telescopes show inconsistencies between the intensity peaks of several molecular line emission and that of the continuum emission, suggesting complex distributions of molecular abundances around L1251A. The SMA interferometer data, however, show intensity peaks of CO 2-1 and $^{13}CO$ 2-1 located at the position of IRS 1, which is both the brightest source in IRAC image and the weakest source in the 1.3 mm dust continuum map. IRS 1 is the strongest candidate for being the driving source of a newly detected the compact CO 2-1 outflow. Over the whole region ($14^{\prime}{\times}14^{\prime}$) of L125l-C, 3 Class I and 16 Class II sources have been detected, including three YSOs in L1251A. A comparison with the average projected distance among 19 YSOs in L1251-C and that among 3 YSOs in L1251A suggests L1251-C is an example of low-mass cluster formation, where protostellar objects are forming in a small group.

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