[seminar] Astro Journal Club on 11 February

[Oskari Miettinen]

Dear all,

The Astro Journal Club will be held tomorrow at 10:15 in the seminar room
F-201 of the Physics Department. This time we will discuss about the
recent detection of a biologically interesting molecule in a low-mass
protostar.

Presenter: Oskari Miettinen
Paper title: Detection of glycolaldehyde towards the solar-type protostar
NGC1333 IRAS2A
Authors: Coutens, A., Persson, M.~V., Jorgensen, J.~K., et al.

Abstract:
Glycolaldehyde is a key molecule in the formation of biologically relevant
molecules such as ribose. We report its detection with the Plateau de Bure
interferometer towards the Class 0 young stellar object NGC1333 IRAS2A,
which is only the second solar-type protostar for which this prebiotic
molecule is detected. Local thermodynamic equilibrium analyses of
glycolaldehyde, ethylene glycol (the reduced alcohol of glycolaldehyde)
and methyl formate (the most abundant isomer of glycolaldehyde) were
carried out. The relative abundance of ethylene glycol to glycolaldehyde
is found to be ~5 -higher than in the Class 0 source IRAS 16293-2422 (~1),
but comparable to the lower limits derived in comets (>=3-6). The
different ethylene glycol-to-glycolaldehyde ratios in the two protostars
could be related to different CH3OH:CO compositions of the icy grain
mantles. In particular, a more efficient hydrogenation on the grains in
NGC 1333 IRAS2A would favor the formation of both methanol and ethylene
glycol. In conclusion, it is possible that, like NGC 1333 IRAS2A, other
low-mass protostars show high ethylene glycol-to-glycolaldehyde abundance
ratios. The cometary ratios could consequently be inherited from earlier
stages of star formation, if the young Sun experienced conditions similar
to NGC1333 IRAS2A.

Link to the paper: http://adsabs.harvard.edu/abs/2015arXiv150200896C

Hope to see you all on Wednesday!

Best regards,
Oskari Miettinen