Notes on specific observations

Some observations have no released processed data associated with them. This can either be because they were processed with the 300 MHz version of the pipeline, which produced lower quality data products, or because the automatic identification of calibrators by AUTOCAL (see “Apercal overview“) and subsequent processing failed. In addition, there is a set of observations that were scheduled without RTC & RTD, thus failing to be validated for release since they did not meet the minimum resolution requirement.

Early processing

The following observations have no released processed data products because they were processed with the 300 MHz version of the pipeline, which did not produce data products of the required quality.

Table 1. Observations processed with 300 MHz version of pipeline.

Autocal failures

The following observations have no ingested processed data products because the automatic running of the pipeline failed in their case. Generally this was because of an issue with identifying calibrators. These observations can be manually reprocessed. Access to the raw data can be requested via the helpdesk.

Table 2. Observations not processed due to failure of automatic calibration identification. Notes: *Observations 028-033 failed. **Go backwards for a pol cal that has C/D (see Obs fails below).

Observational failures

If RTC and RTD are unavailable, an observation is considered failed. Some of the early observations from July, which don’t have processed data available, may suffer from this as both RTC and RTD had issues with delay jumps (see System notes). In addition, there are a series of observations from April/May which were inadvertently scheduled without RTC and RTD and thus don’t have processed data which passes validation. These observations are:

Table 3. Observations scheduled without RTC & RTD.

Calibrator identification issues

Two observations, 191207034 and 191207035, do not have processed data products for the first seven beams, as those beams (due to scheduling complications) were not properly identified by AUTOCAL. Given the small number of beams missing, they were not reprocessed. These observations can be manually reprocessed. Access to the raw data can be requested via the helpdesk. 

Reprocessed with manual flags

As part of the data release, observations where essentially all beams failed validation (e.g., four or fewer beams passed) were visually inspected to identify the cause. In some cases there were no obvious causes, other than bright sources in the field. In other cases, inspection revealed an antenna was off-source (e.g., stuck) during the observation or part of the observation occurred while the target field was not visible. In order to increase the quality of the processed data from these fields, they were manually reprocessed with the additional, visually identified, flags applied. Other fields may also benefit from individual flags and reprocessing.

These observations are:

Table 4. Observations manually reprocessed with additional flags.

Reprocessed with correct polarization calibrator

There were two observations where AUTOCAL incorrectly assigned the same flux calibrator to be both the flux and polarization calibrator to the initial call of Apercal. These observations were reprocessed with the correct polarization calibrator.

Table 5. Observations manually reprocessed with correct polarization calibrator.

Problems with polarization data

There is one dataset which has no polarized data products as a polarized calibrator was not able to be observed in the same observational setup. This is ObsID 200309042, field S1042+5324.

In addition, the observation 200505057 was processed without a polarization calibrator. However, since it has no released processed data due to missing RTC and RTD and thus failing resolution requirements, it was not reprocessed. These observations can be manually reprocessed. Access to the raw data can be requested via the helpdesk.