Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.naic.edu/vscience/schedule/tpfiles/SaltertagA2334tp.ps Äàòà èçìåíåíèÿ: Thu Jun 7 20:26:19 2007 Äàòà èíäåêñèðîâàíèÿ: Sat Dec 22 22:27:54 2007 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: arp 220

Proposal Identification No.: A2334 Date Received: 2007­Jun­01 19:59:11
Technical Page
Proposal Type: Regular
General Category: Astronomy
Sub­Category: Spectroscopy
Observation Category: Extragalactic
Total Time Requested: 36 Hours
Minimum Useful Time: 1 hr
Proposal Title: A Cm­wavelength Search for Prebiotic (and Other) Molecules in Arp 220­like
Starburst Galaxies
ABSTRACT:
Our on­going Arecibo line search (Project A2234) of the prototypical starburst/megamaser galaxy, Arp 220, has
revealed a spectrum rich in molecular transitions. These include the ``pre­biotic'' molecules, methanimine (CH 2 NH)
in emission, three v2=1 absorption lines of HCN, and possibly formic acid (HCOOH). In particular, the (rest)
frequency range 4450­5300 MHz contains methanimine, formaldehyde, CH and formamide (NH 2 CHO) in emission,
plus HCN (v2=1, J=4) and three lines of excited­OH in absorption. Our results mark the first distant
extragalactic detection of methanimine, a molecule with high relevance to the origins of life. Further, the strong,
but previously undetected, cm­wave HCN v2=1 direct l­type lines can aid the study of dense molecular gas and
active star­forming regions in starburst galaxies. Consequently, we now propose observing the 4450­5300 MHz band
towards 21 ``Arp­220''­like galaxies, chosen such that emission and absorption lines of the strength found in Arp
220 would be clearly detected in them.
Name Institution E­mail Phone Student
Christopher J Salter NAIC csalter@naic.edu 787­878 2612 X
281
no
Remote Observing Request
X Observer will travel to AO
Remote Observing
In Absentia (instructions to oper­
ator)
Instrument Setup
C
Atmospheric Observation Instruments:
1

Special Equipment or setup: none
RFI Considerations
Frequency Ranges Planned
4450­5300
2