SIMBAD references

2006A&A...457..927G - Astronomy and Astrophysics, volume 457, 927-936 (2006/10-3)

Formation of methyl formate and other organic species in the warm-up phase of hot molecular cores.


Abstract (from CDS):

The production of saturated organic molecules in hot cores and corinos is not well understood. The standard approach is to assume that, as temperatures heat up during star formation, methanol and other species evaporate from grain surfaces and undergo a warm gas-phase chemistry at 100K or greater to produce species such as methyl formate, dimethyl ether, and others. But a series of laboratory results shows that protonated ions, typical precursors to final products in ion-molecule schemes, tend to fragment upon dissociative recombination with electrons rather than just ejecting a hydrogen atom. Moreover, the specific proposed reaction to produce protonated methyl formate is now known not to occur at all. We utilize a gas-grain chemical network to probe the chemistry of the relatively ignored stage of hot core evolution during which the protostar switches on and the temperature of the surrounding gas and dust rises from 10K to over 100K. During this stage, surface chemistry involving heavy radicals becomes more important as surface hydrogen atoms tend to evaporate rather than react. Our results show that complex species such as methyl formate, formic acid, and dimethyl ether can be produced in large abundance during the protostellar switch-on phase, but that both grain-surface and gas-phase processes help to produce most species. The longer the timescale for protostellar switch-on, the more important the surface processes.

Abstract Copyright:

Journal keyword(s): astrochemistry - stars: formation - ISM: abundances - ISM: clouds - ISM: molecules

CDS comments: In ref list 2004ApJ.615.354B instead of 2004ApJ.260.909B

Simbad objects: 6

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2006A&A...457..927G and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact