CH 3CN observations toward southern massive star-forming regions
Por:
Araya E., Hofner P., Kurtz S., Bronfman L., DeDeo S.
Publicada:
1 ene 2005
Resumen:
In an effort to identify very young sites of massive star formation, we have conducted a survey for hot and dense molecular cores toward a sample of 17 southern sources. The sample consists of sources with IRAS color characteristics of ultracompact H n regions for which high-density molecular material had previously been detected. We observed the J = 5-4, 6-5, 8-7, and 12-11 rotational transitions of CH 3CN and derived rotation temperatures and column densities using the population-diagram technique. We identify four sources with a high-temperature molecular component (7 rot > 90 K) as new candidates for hot molecular cores. We also observed the transitions H35?, CS J = 3-2, and the continuum in the 3, 2 mm bands toward 17 sources, and the 1.3 mm continuum, H41 ? and 13CO J = 2-1 transitions toward 10 sources. Eight sources show blue and red wings in the CS J = 3-2 line, whereas three sources show wings in the 13CO J = 2-1 spectra, suggestive of molecular outflows. Our continuum and recombination line data show that the 91 GHz continuum emission is dominated by free-free emission from ionized regions, whereas at 147 GHz emission from dust grains contributes significantly. © 2005. The American Astronomical Society, All rights reserved.
Filiaciones:
Araya E.:
Physics Department, New Mexico Tech., 801 Leroy Place, Socorro, NM 87801, United States
Hofner P.:
Physics Department, New Mexico Tech., 801 Leroy Place, Socorro, NM 87801, United States
National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801, United States
Kurtz S.:
Centra de Radioastronomía y Astrofísica, UNAM, Apartado Postal 3-72, 58089, Morelia, Michoacan, Mexico
Bronfman L.:
Departamento de Astronomia, Universidad de Chile, Casilla 36-D, Santiago, Chile
DeDeo S.:
Arecibo Observatory, HC3 P.O. Box 53995, Arecibo, 006121, China
|