During the period June 29th - August 24th 2015 the Radio Observatory pipelines wrote LOFAR Measurement Sets (MSs) in a manner inconsistent with the MS definition v2 because:

• a change in the coordinates by NRAO since release 2.0 introduced a type Undefined and an MS produced with a casacore newer than release 1.7 is not readable by old CASA.

Also, all LOFAR MS have been generated with two tables (STATE,PROCESSOR) missing. However, since release 4.1 a check for tables is done by CASA, thus causing a failure.

Users working with CASA 4.1 or higher on MS generated before September 2nd 2015 need to fix their MSes.

A script to add missing tables in the MS to conform with CASA standards and to make a fix in the MeasInfo in the spectral window table is available here. The software requirements to run this script on your systems are:

1. TaQL (so casacore)

2. pyrap

Usage:

> tar -xvf fixLofarMSAug2015.py.tar

> python fixLofarMSAug2015.py <name MS>

In case you experience issues when running this script, please contact Science Operations and Support through the RO helpdesk which is hosted at https://support.astron.nl/rohelpdesk