Table · dataset · 2016
Protonated formaldehyde in L1689B
Listed in IVOA Registry (Virtual Observatory)
Complex organic molecules (COMs) are detected in many regions of the interstellar medium, including prestellar cores.
Description
However, their formation mechanisms in cold (~10K) cores remain to this date poorly understood. The formyl radical HCO is an important candidate precursor for several O-bearing terrestrial COMs in cores, as an abundant building block of many of these molecules.
Several chemical routes have been proposed to account for its formation, both on grain surfaces, as an incompletely hydrogenated product of H addition to frozen-out CO molecules, or in the gas phase, either the product of the reaction between H_2_CO and a radical, or as a product of dissociative recombination of protonated formaldehyde H_2_COH^+^. The detection and abundance determination of H_2_COH^+^, if present, could provide clues as to whether this latter scenario might apply.
Read the rest (2 more)
We searched for protonated formaldehyde H_2_COH^+^ in the prestellar core L1689B using the IRAM 30m telescope. The H_2_COH^+^ ion is unambiguously detected, for the first time in a cold (~10K) source. The derived abundance agrees with a scenario in which the formation of H_2_COH^+^ results from the protonation of formaldehyde.
We use this abundance value to constrain the branching ratio of the dissociative recombination of H2COH+ towards the HCO channel to ~10-30%. This value could however be smaller if HCO can be efficiently formed from gas-phase neutral- neutral reactions, and we stress the need for laboratory measurements of the rate constants of these reactions at 10K. Given the experimental difficulties in measuring branching ratios experimentally, observations can bring valuable constraints on these values, and provide a useful input for chemical networks.
Links
Where it is published
- Reference page cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/588/L8 ↗
landing page · from IVOA Registry
Documentation and papers
- ADS 2016A&A...588L...8B ui.adsabs.harvard.edu/abs/2016A%26A...588L...8B ↗
publication · from IVOA Registry
Catalogue records · 2
- VOResource record dc.g-vo.org/oai.xml?verb=GetRecord&metadataPrefix=ivo_vor&identifier=ivo%3… ↗
metadata API · from IVOA Registry
- Registry record (GAVO) dc.g-vo.org/I/cds.vizier/j/a%2Ba/588/l8 ↗
catalogue entry · from IVOA Registry
Topics
- Stated by source
- Optical
- From keywords
- Astronomy & Astrophysics
Provenance · 1 source records, 8 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| IVOA Registry (Virtual Observatory) | ivo://cds.vizier/j/a+a/588/l8 | 15 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| access_level | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[field].local:field:astronomy | mapping · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| concepts[modality].ivoa_waveband:optical | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| description | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_description |
| license_text | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| publication_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 | |
| title | source · IVOA Registry | connector:ivoa_registry@1.0.0 | rr.resource.res_title |
| updated_date | source · IVOA Registry | connector:ivoa_registry@1.0.0 |