LOFAR Status Meeting :: 15 Dec 2010

Status of the array:

• 26 NL stations operational: 20 core stations and 6 remote stations.
• 6 NL stations expected to become operational early next year (5 core, 1 remote)
• Observations are made with a new MAC version which includes the new beamserver, the fix of the HBA1 problem and using static station delay-calibration as default.
• Aiming to have the full compliment of station delay-calibration tables by the end of 2010. The availability of calibration tables per station can be found at the last column of the station list in the LOFAR Operations Wiki “White Board” page: http://www.lofar.org/operations/doku.php?id=operator:current_station_overview
• Inteferometry observations are flagged (either with the MADFLAGGER or RFIconsole) and compressed, by support scientists using the pipeline framework.

Recent activities in the observing system:

The new version of SCHEDULER which includes resource management and the related changes in other elements of the observing system, have been tested during weeks 49 and 50.

Some Recent Commissioning Activities:

• Imaging Busy Week (Dec 14-16, Leiden):
  • Investigating the global bandpass
  • Test of facet-based imaging script
  • Comparisons of 74MHz flux densities with VLSS

• Beam Model Validation:
  • The “Beam team” worked with Cygnus LBA drift scans. They demonstrated the improvement of the beam with the station calibration and that the beam at the center of the image is accurate to within a few percent of the predicted value.

Technical issues under investigation:

• Problems with Calserver at some stations: Temporary solution implemented
• International stations: Transmit 61 instead of 62 beamlets (Week 49-50): work ongoing.
• NL stations LBA_outer polarization: Software solution under development.
• RSP boards jump into ERROR state, need recycle of 48V power to reset: Debugging planned for early Jan 2011.