Search for Class I methanol masers in low-mass star formation regions
Artikel i vetenskaplig tidskrift, 2010
A survey of young bipolar outflows in regions of low-to-intermediate-mass star formation has been carried out in two Class I methanol maser transitions: 7(0) - 6(1)A+ at 44 GHz and 4(-1) - 3(0)E at 36 GHz. We detected narrow features towards NGC 1333I2A, NGC 1333I4A, HH25MMS and L1157 at 44 GHz, and towards NGC 2023 at 36 GHz. Flux densities of the lines detected at 44 GHz are no higher than 11 Jy and the relevant source luminosities are about 1022 erg s-1, which is much lower than those of strong masers in high-mass star formation regions. No emission was found towards 39 outflows. All masers detected at 44 GHz are located in clouds with methanol column densities of the order of or larger than a few x1014 cm-2. The upper limits for the non-detections are typically of the order of 3-5 Jy. Observations in 2004, 2006 and 2008 did not reveal any significant variability of the 44 GHz masers in NGC 1333I4A, HH25MMS and L1157.
masers
young stellar objects
lines: ISM
bok globules
ISM: jets and outflows
jet-driven
emission
co outflows
ISM: clouds
bipolar
ngc 1333
outflows
ISM: molecules
radio
driven molecular outflow
cloud core
hh 24-26
Författare
S. V. Kalenskii
Russian Academy of Sciences
Lars E B Johansson
Chalmers, Institutionen för radio- och rymdvetenskap, Nationella anläggningen för radioastronomi
Per Bergman
Chalmers, Institutionen för radio- och rymdvetenskap, Nationella anläggningen för radioastronomi
S. Kurtz
Universidad Nacional Autónoma de México
P. Hofner
New Mexico Institute of Mining and Technology
Max-Planck-Gesellschaft
National Radio Astronomy Observatory Socorro
C. M. Walmsley
Osservatorio Astrofisico di Arcetri
V. I. Slysh
Chalmers, Institutionen för radio- och rymdvetenskap, Nationella anläggningen för radioastronomi
Monthly Notices of the Royal Astronomical Society
0035-8711 (ISSN) 1365-2966 (eISSN)
Vol. 405 1 613-620Ämneskategorier
Fysik
Fundament
Grundläggande vetenskaper
DOI
10.1111/j.1365-2966.2010.16484.x