Water and Methanol Ice in L1544

From WebRef.org
Jump to navigationJump to search New System Mechanic® Ultimate Defense™. Total Performance, Protection & Privacy.

Miwa Goto (1), A. I. Vasyunin (2,3), B. M. Giuliano (4), I. Jiménez-Serra (5), P. Caselli (4), C. G. Román-Zúñiga (6), J. Alves (7) ((1) Universitäts-Sternwarte München, Ludwig-Maximilians-Universität, Munich, Germany, (2) Ural Federal University, Yekaterinburg, Russia, (3) Visiting Leading Researcher, Ventspils International Radio Astronomy Centre, Ventspils, Latvia, (4) Max-Planck-Institut für extraterrestrische Physik, Garching, Germany, (5) Centro de Astrobiología, Instituto Nacional de Técnica Aeroespacial, Madrid, Spain, (6) Universidad Nacional, Autonóma de México, Ensenada, BC, Mexico, (7) Universität Wien, Department of Astrophysics, Wien, Austria)

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. The model calls for a high abundance of methanol ice at the edge of the CO freeze-out zone in cold cloud cores. We performed medium resolution spectroscopy toward 3 field stars behind the starless core L1544 at 3 μm to constrain the methanol ice abundance and compare it with the model predictions. 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 smaller than predicted. The reason for the disagreement between the observations and the model calculations is not yet understood.


Sponsor: Health Supplements | Sleep better, stress less, support your brain and hair growth | Shop Now

Auto Europe Car Rentals