Water and Methanol Ice in L1544

Author(s)
Miwa Goto, A. I. Vasyunin, B. M. Giuliano, I. Jiménez-Serra, P. Caselli, C. G. Román-Zúñiga, J. Alves
Abstract

Context. Methanol and complex organic molecules have been found in cold starless cores, where a standard warm-up scenario would not work because of the absence of heat sources. A recent chemical model attributed the presence of methanol and large organics to the efficient chemical desorption and a class of neutral-neutral reactions that proceed fast at low temperatures in the gas phase.

Aims. The model calls for a high abundance of methanol ice at the edge of the CO freeze-out zone in cold cloud cores.

Methods. We performed medium-resolution spectroscopy toward three field stars behind the starless core L 1544 at 3 μm to constrain the methanol ice abundance and compare it with the model predictions.

Results. One of the field stars shows a methanol ice abundance of 11% with respect to water ice. This is higher than the typical methanol abundance previously found in cold cloud cores (4%), but is 4.5 times lower than predicted. The reason for the disagreement between the observations and the model calculations is not yet understood.

Organisation(s)
Department of Astrophysics
External organisation(s)
Ludwig-Maximilians-Universität München, Ural Federal University, Ventspils University of Applied Sciences, Max-Planck-Institut für extraterrestrische Physik, National Institute of Aerospace Technology, Universidad Nacional Autonoma de Mexico
Journal
Astronomy & Astrophysics
Volume
651
No. of pages
8
ISSN
0004-6361
DOI
https://doi.org/10.1051/0004-6361/201936385
Publication date
07-2021
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Keywords
ASJC Scopus subject areas
Astronomy and Astrophysics, Space and Planetary Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/8392e605-20d4-471d-bebf-1c33e8b77f1f