LOFAR Polarization Commissioning by the MKSP

Transcription

1 LOFAR Polarization Commissioning by the MKSP James M Anderson anderson@mpifr-bonn.mpg.de On behalf of the LOFAR collaboration Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 1/15

2 Timeline 2010 March Polarized Pulsar Catalog Survey 2010 March End--April RM Synthesis Subband Optimization: Pulsars 2010 April Mid RM Synthesis Software Testing 2010 April (MKSP Meeting?) RM Synthesis Subband Optimization: Fan Region 2010 May RM Synthesis Software Testing 2010 May Long Baseline Pulsar Calibrator Survey 2010 June RM Synthesis Software Testing 2010 June Jupiter Circular Polarization Waiting for June for the Solar elongation to be > 60 degrees for good calibration 2010 June RM Synthesis Subband Optimization: AGN Waiting for a sufficient number of LBA + HBA international stations 2010??? Long Baseline MS 3 Blue: specific interaction with Surveys KSP needed/desired Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 2/15

3 Polarized Pulsar Catalog Survey Find fundamental polarization calibrators on the sky for LOFAR High frequency observations already give us the position angle Test basic ionospheric calibration Operational requirements Proposal written Beamformed data processing handles full Stokes Really prefer to have Superterp stations connected to common clock Operational realtime station antenna delay/gain calibration for LBA and HBA Snapshot observing mode Multiple beam observing mode ~ 50 Gb/s recording rate if pulsar pulse phase averaging mode not available in Blue Gene Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 3/15

4 RM Synthesis Subband Optimization Determine standard subband selection setups for LOFAR polarization observations RM Synthesis optimization Calibration of instrument, ionosphere Coordination with Surveys KSP for joint/piggybacking observations Operational requirements Operational realtime station antenna delay/gain calibration for LBA and HBA Snapshot observing mode Multiple beam observing mode Polarized Pulsar Catalog Survey completed Fast RCUMODE switching Fast switching between LBA and HBA Fast subband selection switching Fast clock mode (200 MHz <=> 160 MHz) switching BBS capable of calibrating some beam directions using other beam directions and different phase/amplitude calibrator observations Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 4/15

5 Subband Optimization: Pulsars Point source tests Operational requirements At least 10 Dutch stations (baselines < 30 km) Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 5/15

6 Subband Optimization: Fan Region Extended source test Hope to schedule for MKSP Meeting in Dwingeloo, April Operational requirements At least 12 Core stations Operational version of RM Synthesis software for processing data Imaging software capable of dealing with making frequency cubes Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 6/15

7 Subband Optimization: AGN Long baseline, complicated, weak source tests Operational requirements At least 3 International stations (HBA + LBA) LEA066 Long Baseline Calibrator Survey completed Long baseline calibration software ready Operational version of RM Synthesis software for processing data Imaging software capable of dealing with making frequency cubes Long Baseline Pulsar Calibrator Survey completed ~ 50 Gb/s recording rate Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 7/15

8 Long Baseline Pulsar Calibrator Survey Find which pulsars for short-baseline polarization calibration are also good on long baselines Expect scattering in the ISM to broaden most pulsars so severely that they cannot be detected on long LOFAR baselines Operational requirements At least 3 International stations (HBA + LBA) LEA066 Long Baseline Calibrator Survey completed Long baseline calibration software ready BBS capable of calibrating some beam directions using other beam directions and different phase/amplitude calibrator observations Operational realtime station antenna delay/gain calibration for LBA and HBA Snapshot observing mode Multiple beam observing mode Polarized Pulsar Catalog Survey completed ~ 50 Gb/s recording rate Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 8/15

9 Jupiter Circular Polarization Circular polarization testing, including long baselines Operational requirements At least 3 International stations for LBA BBS capable of calibrating some beam directions using other beam directions and different phase/amplitude calibrator observations LEA066 Long Baseline Calibrator Survey completed Long baseline calibration software ready Imaging software capable of dealing with making frequency cubes Operational realtime station antenna delay/gain calibration for LBA and HBA Snapshot observing mode Multiple beam observing mode Polarized Pulsar Catalog Survey completed ~ 50 Gb/s recording rate > 60 degrees elongation from the Sun Should be scheduled as three 3 hour runs, with at least one or two weeks between observations Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 9/15

10 RM Synthesis Software Testing Software testing on Groningen cluster Operational requirements Test version of RM Synthesis software installed on cluster Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 10/15

11 Long Baseline MS 3 Including long baselines into MS 3 Searching for polarization calibrators for long baselines Operational requirements At least 3 International stations (HBA + LBA) LEA066 Long Baseline Calibrator Survey completed Long baseline calibration software ready BBS capable of calibrating some beam directions using other beam directions and different phase/amplitude calibrator observations Imaging software capable of dealing with making frequency cubes Operational realtime station antenna delay/gain calibration for LBA and HBA Snapshot observing mode Multiple beam observing mode Polarized Pulsar Catalog Survey completed ~ 50 Gb/s recording rate Long Baseline Pulsar Calibrator Survey completed RM Synthesis Subband Optimization: AGN completed 1 PB of 6 month archive space available Averaging of visibilities post-flagging tested Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 11/15

12 Hardware Status G Heald LOFAR Wiki/A Gunst 29 Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 12/15

13 Polarization Software Key problem for MKSP commissioning RM Synthesis preliminary version supposed to be ready by April Polarization calibration needs to be put into BBS Polarization models need to be put into GSM Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 13/15

14 Commissioning Manpower Key problem for MKSP commissioning Don't have enough people who can devote large amounts of time to commissioning Currently hiring PhD students and a postdoc for commissioning in Germany, but they will not be ready for the early commissioning phase Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 14/15

15 The End Surveys KSP Meeting, Leiden, 2010 March 11 James M Anderson 15/15