[seminar] Astro Journal Club on 12 Nov

[Oskari Miettinen]

Dear all,

We will meet again on Wednesday at 10:00 am for our weekly Astro Journal
Club in the seminar room F-201 of the Physics Department. This week we
will discuss about the first CO(17-16) spectral line detection towards a
z>6 quasar.

Presenter: Oskari Miettinen
Paper title: First CO(17-16) emission line detected in a z > 6 quasar
Authors: Gallerani, S., Ferrara, A., Neri, R., and Maiolino, R.
Reference: 2014, MNRAS, 445, 2848

Abstract:
We report the serendipitous detection of the CO(17-16) emission line
towards the quasar sloan digital sky survey J114816.64+525150.3 (J1148) at
redshift z = 6.4 obtained with the Plateau de Bure Interferometer. The
CO(17-16) line is possibly contaminated by OH+ emission, that may account
for 35-60 per cent of the total flux observed. Photodissociation and
X-ray-dominated regions (PDRs and XDRs) models show that PDRs alone cannot
reproduce the high luminosity of the CO(17-16) line relative to low-J CO
transitions and that XDRs are required. By adopting a composite PDR+XDR
model, we derive molecular cloud and radiation field properties in the
nuclear region of J1148. Our results show that highly excited CO lines
represent a sensitive and possibly unique tool to infer the presence of
X-ray faint or obscured supermassive black hole progenitors in high-z
galaxies.

Link to the paper: http://adsabs.harvard.edu/abs/2014MNRAS.445.2848G

Hope to see you all on Wednesday.

Best regards,
Oskari