Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.naic.edu/vscience/schedule/tpfiles/FreudlingtagA1956tp.pdf Дата изменения: Tue Aug 15 19:53:15 2006 Дата индексирования: Sat Dec 22 23:45:39 2007 Кодировка: Поисковые слова: millisecond pulsar

Proposal Identification No.:

A1956

Date Received: 2004 -Jun-01 18:47:51

Technical Page
Proposal Type: General Category: Sub-Category: Observation Category: Total Time Requested: Prop osal Title: ABSTRACT: Regular Astronomy Spectroscopy Extragalactic 70 Hours

Precursor Observations for the Alfa Ultra Deep Survey (AUDS)

The improved spatial and spectral survey capabilities available with ALFA will open a new era of high sensitivity observations for the Arecibo telescope. In principle, it is possible to achieve noise of less than 50 µJy per with integration times of about 100 hours, which translates into a 1 HI mass sensitivity of a few 108 M at a redshift of 0.16. Surveys of such sensitivity could be used to, e.g. investigate the evolution of HI gas in the universe, directly detect Lyman-limit systems, explore the low-density gas around the edges of galaxies and search for OH megamasers. Enabling ultra-sensitive observations at Arecibo would therefore open whole new fields of research to the observatory. In this proposal, we request observing time for a set of precursor observation to test the feasibility of such very deep ALFA observations and find the limitations of such observations. The proposed strategy is to obtain multiple drift scans over a field with known late-type disk galaxies close to the redshift limit and close to the optimal Arecibo declination at night. The total time request is 70 hours of observing time. The target field for this precursor proposal includes the low redshift target NGC~ 7523. The observations will serve as a technical test for high redshift observations and simultaneously search for extended HI emission around NGC~ 7523. If successful, this search will lead to the first detection of the unionized fraction of the low column-density hydrogen in emission outside the Local Group.

Name Wolfram Freudling

Institution European Southern Observatory

E-mail wfreudli@eso.org

Phone 01149-8932006425

Student no

Service Observing Request

Remot e Observing Request

X

None All of the observing run. Part of the observing run. Queue Observing X

No Maybe Yes

Instrument Setup
ALFA 1


Atmospheric Observation Instruments:

Sp ecial Equipment or setup:

none

RFI Considerations Frequency Ranges Planned
1220-1420 This proposal requires coordination with Punta Salinas radar within the band 1222-1381 MHz.. This proposal requires coordination with GPS L3 at 1381 MHz.

2