Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/vscience/schedule/tpfiles/GinsburgtagA2584tp.ps Дата изменения: Wed Jun 9 00:20:45 2010 Дата индексирования: Fri Feb 11 19:26:11 2011 Кодировка: Поисковые слова: star

Proposal Identification No.: A2584 Date Received: 2010­Jun­01 12:40:03
Technical Page
Proposal Type: Regular
General Category: Astronomy
Sub­Category: Spectroscopy
Observation Category:
Total Time Requested: 66 Hours
Minimum Useful Time: 2h
Proposal Title: Densitometry of star­forming dusty clumps throughout the Galaxy
ABSTRACT:
We propose to obtain measurements of the dense mass fraction of young star­forming complexes in a variety of
Galactic environments using beam­matched formaldehyde absorption line observations on the GBT at 2 cm and
Arecibo at 6 cm. The pilot program GBT09C­049, combined with archival Arecibo data, demonstrated the
possibility of e#ciently measuring dense gas mass fractions in Galactic molecular clumps with the GBT and
Arecibo. We propose to expand that initial sample of 22 ultracompact HII regions to 409 clumps in a wide range of
evolutionary states, including inactive and star­forming infrared dark clouds, HII regions, and filamentary
structures. We will use formaldehyde densitometry to measure the density and dense gas mass fraction in these 409
clumps. These measurements will be used to track the evolutionary path of molecular clumps intermediate between
giant molecular clouds and protostellar cores, and the large sample size will allow us to estimate the relative
lifetimes of each state. The GBT observations have already been approved, but completion of this project depends
critically on the Arecibo data.
Name Institution E­mail Phone Student
Adam Ginsburg University of Col­
orado, Boulder
adam.ginsburg@colorado.edu 303­667­3805 G
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
4818 ­ 4840
4582 ­ 4604
5414 ­ 5586
5114 ­ 5286
4664 ­ 4836
4544 ­ 4716
4412 ­ 4584
2