Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.naic.edu/vscience/schedule/tpfiles/MomjiantagA2234tp.ps Äàòà èçìåíåíèÿ: Thu Nov 17 22:05:03 2011 Äàòà èíäåêñèðîâàíèÿ: Mon Feb 4 20:56:14 2013 Êîäèðîâêà: Ïîèñêîâûå ñëîâà: arp 220

Proposal Identification No.: A2234 Date Received: 2006 ­Jun­04 15:35:32
Technical Page
Proposal Type: Regular
General Category: Astronomy
Sub­Category: Spectroscopy
Observation Category: Extragalactic
Total Time Requested: 28 Hours
Minimum Useful Time: 2 hours
Proposal Title: Probing the ISM of Arp 220 -- A Cm­Wavelength Spectral­line Census
ABSTRACT:
We propose making an Arecibo spectral­line census for the prototype ULIRG, Arp 220, to investigate its various
atomic/molecular­line transitions (both in emission and absorption) using full coverage of L­band and from 3 to 10
GHz. Included are a huge number of Radio Recombinations Lines (RRLs) to better constrain RRL emission
models, while the molecular­line census will allow better understanding of nuclear starbursts in ULIRGs. Within
this census, we will observe the 6.7­GHz methanol maser line, as yet undetected beyond the Local Group. This will
determine whether methanol masers in ULIRGs exhibit kilo/megamasing compared to Galactic examples, as with
18­cm OH. Although scientifically focused, the project also addresses several technical objectives. Arp 220 being a
strong continuum emitter, we will investigate the necessity of Double Position Switching (commonly used at
L­band) for frequencies between 2 and 10 GHz. Moreover, considering the great Arp­220 line­widths and the
multiple transitions of some lines, including RRLs, we will use the project to ``shake down'' the 8­subcorrelator
(800­MHz bandwidth) single­pixel capability of the WAPP spectrometer, which is just being implemented.
Name Institution E­mail Phone Student
Emmanuel A Momjian Arecibo Observa­
tory/NAIC
emomjian@naic.edu 787 878 2612
extn. 251
no
Remote Observing Request
X Observer will travel to AO
Remote Observing
In Absentia (instructions to oper­
ator)
Instrument Setup
L­wide C X­high S­high C­high
Atmospheric Observation Instruments:
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Special Equipment or setup: This proposal requires the use of the 800­MHz, single­pixel capability
of the WAPPs to be in place before it can commence (will require double of the requested telescope time
otherwise).
RFI Considerations
Frequency Ranges Planned
1100 ­ 10,000 MHz
This proposal requires Iridium RFI protection at 1612 MHz between 10pm and 6am EST.
This proposal requires coordination with Punta Salinas radar within the band 1222­1381 MHz..
This proposal requires coordination with GPS L3 at 1381 MHz.
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