The desorption of H2CO from interstellar grains analogues

Publication

Reference: Raunier S. (2004). The desorption of H2CO from interstellar grains analogues. Astron. Astrophys., 416, 165 - 169.

Names

Title: The desorption of H2CO from interstellar grains analogues
Abstract: Laboratory experiments involving vacuum ultraviolet (VUV) irradiation of solid isocyanic acid (HNCO) at 10 K, followed by infrared spectroscopy (FTIR), are used to interpret the complex spectra associated with Interstellar Medium (ISM) dust grains, particularly the spectra associated with the icy phase observed toward dense molecular clouds. The comparison of the infrared spectra of the photolysis products with spectra recorded from the protostellar source NGC 7538 IRS9 shows that the “unexplained” 1700 cm−1 feature can be attributed to the contribution of several species H2CO (formaldehyde), HCONH2 (formamide) and H2NCONH2 (urea) mixed with H2O as the main contributor. Urea, formaldehyde and NH+4 OCN− (ammonium cyanate) may also contribute to a band at 1470 cm−1, widely observed in many protostellar infrared sources and which remains up to now poorly explained in numerous ISO-SWS spectra. Isocyanic acid could be a precursor of formamide and urea in interstellar ices.
Keywords: astrochemistry, molecular processes, ISM: molecules, molecular data
Content: species, spectral data

Doi

10.1051/0004-6361:20034558

Identifiers