Detection Of Key Prebiotic Molecule PO in Star-forming Regions

Phosphorus is a crucial element in biochemistry, especially the P-O bond, which is key for the formation of the backbone of the deoxyribonucleic acid.

So far, PO has only been detected towards the envelope of evolved stars, and never towards star-forming regions. We report the first detection of PO towards two massive star-forming regions, W51 e1/e2 and W3(OH), using data from the IRAM 30m telescope. PN has also been detected towards the two regions. The abundance ratio PO/PN is 1.8 and 3 for W51 and W3(OH), respectively. Our chemical model indicates that the two molecules are chemically related and are formed via gas-phase ion-molecule and neutral-neutral reactions during the cold collapse.

The molecules freeze out onto grains at the end of the collapse and desorb during the warm-up phase once the temperature reaches 35 K. Similar abundances of the two species are expected during a period of 5x10^{4} yr at the early stages of the warm-up phase, when the temperature is in the range 35-90 K. The observed molecular abundances of 10^{-10} are predicted by the model if a relatively high initial abundance of 5x10^{-9} of depleted phosphorus is assumed.

V. M. Rivilla, F. Fontani, M. T. Beltrán, A. Vasyunin, P. Caselli, J. Martín-Pintado, R. Cesaroni
(Submitted on 19 May 2016)

Comments: 9 pages, 7 figures, 6 tables. Accepted in Astrophysical Journal
Subjects: Astrophysics of Galaxies (astro-ph.GA); Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:1605.06109 [astro-ph.GA] (or arXiv:1605.06109v1 [astro-ph.GA] for this version)
Submission history
From: Victor Manuel Rivilla
[v1] Thu, 19 May 2016 15:55:18 GMT (142kb)
http://arxiv.org/abs/1605.06109

Please follow Astrobiology on Twitter.


  • submit to reddit