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lbaops:lbascheduling [2019/09/26 17:42]
cormac [ATCA Issues]
lbaops:lbascheduling [2019/09/26 17:42] (current)
cormac [ATCA Issues]
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   *  The array usually needs to be "​re-phased"​. At lower frequencies this may only be every hour or more, but at 20 GHz potentially every 10-20 minutes depending on the array baseline lengths and weather. It is highly recommended you discuss calibration strategies with ATNF LBA support staff. Generally recommendations would be to make sure you regularly observe an appropriate ATCA calibrator source within a few degrees of your target. These sources need to be compact enough that they have close to zero structure phase, have enough flux so the phase spread between the antennas can be quickly determined AND the scan must be long enough to allow the observer to see the phase and run calibration if required. One minute on a compact source with flux density >~ 200 mJy is needed at most frequencies.   *  The array usually needs to be "​re-phased"​. At lower frequencies this may only be every hour or more, but at 20 GHz potentially every 10-20 minutes depending on the array baseline lengths and weather. It is highly recommended you discuss calibration strategies with ATNF LBA support staff. Generally recommendations would be to make sure you regularly observe an appropriate ATCA calibrator source within a few degrees of your target. These sources need to be compact enough that they have close to zero structure phase, have enough flux so the phase spread between the antennas can be quickly determined AND the scan must be long enough to allow the observer to see the phase and run calibration if required. One minute on a compact source with flux density >~ 200 mJy is needed at most frequencies.
  
-  * Due to the frequent resets that are likely to happen during the fringe finder observations at the start of an observation it is strongly ​recommend ​that you do not re-phase ATCA during this part of the schedule.+  * Due to the frequent resets that are likely to happen during the fringe finder observations at the start of an observation it is strongly ​recommended ​that you do not re-phase ATCA during this part of the schedule.
  
 It is strongly recommended to schedule so that phase recalibration happens automatically. You need to be confident the chosen source is an appropriate ATCA calibrator (if it has structure or is weak you will make things worse). You can check the suitability of your source on the ATCA calibrator database: ​ It is strongly recommended to schedule so that phase recalibration happens automatically. You need to be confident the chosen source is an appropriate ATCA calibrator (if it has structure or is weak you will make things worse). You can check the suitability of your source on the ATCA calibrator database: ​
lbaops/lbascheduling.txt · Last modified: 2019/09/26 17:42 by cormac