Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.atnf.csiro.au/whats_on/workshops/mm_science2002/talks/rmanches.pdf Дата изменения: Tue Nov 26 05:49:39 2002 Дата индексирования: Wed Dec 26 10:28:02 2007 Кодировка: Поисковые слова: solar eclipse

ATCA 12mm System

12mm systems currently installed on CA02, CA03 and CA04

Available frequency ranges 16.1-18.9 GHz and 20.1-22.5 GHz Requires module swap to change bands


Measured System Temperature
Polarisations A and B on CA03 at zenith


Atmospheric antenna temperature and opacity
(for good conditions at Narrabri: clear, humidity 20%)

MIRIAD task: OPPLT


Calibration
Phase:
· ~2000 sources known with S20 > 400 mJy. More from WB survey. · Most vary in flux density, some resolved on long baselines.

Amplitude:
· No unresolved and stable sources known · Most reliable calibration from Mars. · MIRIAD tasks PLPLOT and
PLBOOT


Calibrator Flux Densities
Mars used as primary calibrator: 0.3 ­ 1.5Jy. PLBOOT predicts flux density as function of baseline and time.

Uranus also OK (~300 mJy and ~2 arc sec) ­ but gives flux scale 40% lower!


12mm Phase Stability
18.88 GHz 0541-7332 (0.7 Jy) 1990m baseline (125 k)

Not Bad!


12mm Phase Stability

18.88 GHz 0541-7332 (0.7 Jy) 560m baseline (35 k)

Bad!


SN 1987A at 12mm


SN 1987A at 12mm (2km baseline)
2002 Aug 25


12mm Systems: Present
Final systems under construction


Future
· 1 May 2003 ­ Final systems installed on antennas 1, 5 and 6. · 1 June 2003 ­ Systems on antennas 2, 3 and 4 updated.

6 antennas, 6 km baseline Tunable over 16 ­ 26 GHz