EXPANDED VERY LARGE ARRAY CONTINUUM OBSERVATIONS TOWARD HOT MOLECULAR CORE CANDIDATES
Por:
Hofner P., Kurtz S., Ellingsen S.P., Menten K.M., Wyrowski F., Araya E.D., Loinard L., Rodríguez L.F., Cesaroni R.
Publicada:
20 sep 2011
Resumen:
We have used the Expanded Very Large Array (EVLA) with two 1 GHz wide bands to obtain K-band (1.3 cm) continuum observations toward the following five hot molecular core candidates: IRAS 18151 - 1208, IRAS 18182 - 1433, IRAS 18345 - 0641, IRAS 18470 - 0044, and IRAS 19012 + 0536. The sources were selected from the 2002 list of Sridharan et al. and are characterized by high FIR luminosity, dense molecular and dust condensations, massive large-scale CO flows, and the absence of strong cm continuum emission. These properties are indicative of massive star-forming regions in an evolutionary phase prior to ultra-or hypercompact H II regions. We detect a total of 10 individual 1.3 cm continuum sources toward this sample, and derive in-band spectral indices between 19.3 and 25.5 GHz consistent with thermal free-free emission, for all sources except component A in IRAS 18182 - 1433, which has a negative spectral index indicative of synchrotron emission. We suggest that in most cases the 1.3 cm
Filiaciones:
Hofner P.:
Physics Department, New Mexico Tech, 801 Leroy Pl., Socorro, NM 87801, United States
National Radio Astronomy Observatory, P.O. Box O, Socorro, NM 87801, United States
Kurtz S.:
Univ Nacl Autonoma Mexico, Ctr Radioastron & Astrofis, Morelia 58090, Michoacan, Mexico
Ellingsen S.P.:
School of Mathematics and Physics, University of Tasmania, Private Bag 37, Hobart, TAS 7001, Australia
Menten K.M.:
Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
Wyrowski F.:
Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
Araya E.D.:
Physics Department, Western Illinois University, 1 University Circle, Macomb, IL 61455, United States
Loinard L.:
Univ Nacl Autonoma Mexico, Ctr Radioastron & Astrofis, Morelia 58090, Michoacan, Mexico
Rodríguez L.F.:
Univ Nacl Autonoma Mexico, Ctr Radioastron & Astrofis, Morelia 58090, Michoacan, Mexico
Cesaroni R.:
INAF, Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy
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