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: http://www.naic.edu/~ngc2903/n2903_run1.htm
Дата изменения: Fri Dec 10 23:04:58 2004 Дата индексирования: Mon Oct 1 22:27:20 2012 Кодировка: Поисковые слова: п п п п п п п п п п п п |
Setup | Setting | Comment |
---|---|---|
Center Freq | 1417 MHz |   |
LO tracking | None (Topocentric) | Best for rfi identification; unfortunately Doppler correction, although computed, not recorded in FITS file. |
Bandwidth | 12.5 MHz |   |
Sampling | 9 level auto | Best for sensitivity and rfi mitigation |
# channels | 2048/pol | (9 level reduces total # chans by half) |
Drift length | 480 seconds | The drift then lasts 8 minutes, and is set to begin when Beam 0 crosses RA(NGC2903) - 4 min. The CAL time is additional. |
Cal mode | loopend or loopstart | All except Dec03 done in loop end. LIVEDATA requires loop start which Mary used on 12/03. However, then the actual drift start/stop times are not fixed, and this complicates true position checking vs. header positions (needed for continuum tests). Concerns raised about possible firing of cal on top of continuum source if fired at fixed point on sky throughout night. Mikael will add option for loopstart+loopend before run 2. Note that it takes 7 or 8 seconds beyond the end of the 480 sec drift to complete the 1 sec CalON plus 1 sec CalOFF. If we decide to select loopstart+loopend, that may require an additional overhead of 5-8 secs. |
CIMA files | FixedAzdrift | Sources /home/lerner/fixedAZ2.tcl (executive) and /home/lerner/fixedAZ2_widget.tcl (gui) |
  | "Saved state" | a1963_hiline.gui |
Setup | Setting | Comment |
---|---|---|
Center Freq | 1405 MHz |   |
LO tracking | None (Topocentric) | Best for rfi identification; unfortunately Doppler correction, although computed, not recorded in FITS file. |
Bandwidth | 50 MHz |   |
Sampling | 9 level auto | Best for sensitivity and rfi mitigation |
# channels | 2048/pol | (9 level reduces total # chans by half) |
Drift length | 240 seconds | The drift then lasts 4 minutes, and is set to begin when Beam 0 crosses RA(calibrator) - 2 min. The CAL time is additional. |
Cal mode | loopend | Better idea for position checks. See note above. |
CIMA files | FixedAzdrift | Sources /home/lerner/fixedAZ2.tcl (executive) and /home/lerner/fixedAZ2_widget.tcl (gui) |
  | "Saved state" | a1963_beammaps.gui |