This page provides information about pipeline processing and data types.
Raw data are selected, associated and inserted into a reduction mechanism which produces calibration products, science products and quality control information. This mechanism is the data processing pipeline. There is one such pipeline for each VLT and VLTI instrument.
Find general information about ESO reduction pipelines here.
The main functionalities of the pipelines are:
QC Garching creates master calibration data from all raw calibration data. The raw data are stored in the ESO Archive and are public. They are quality-checked and used for data reduction and for trending.
Before October 2011 QC Garching processed science data, using the best available, quality-checked master calibration data. As of October 2011 this service is not offered anymore.
There are two instances of the data reduction pipelines:
The automatic mode is used for quick look purposes and for on-site quality control. It processes all raw data sequentially, as they arrive from the instrument. If calibration products ("master calibrations") are required for processing science data, these are taken from a database with standard, pre-manufactured calibration products. The automatic mode is not tuned to obtain the best possible results.
The optimized mode is the mode, which uses all data of a night, including the daytime calibrations. The calibration data are sorted and grouped according to their dependencies. Master calibration data are created. Their quality is checked.
Pipeline products from AMBER are stored as FITS binary table files using generalized Optical/IR interferometry conventions. Find informations about this format here. More details can also be found in this document.
The Pipeline is available from here.
Until October 2011 all science data were processed by QC Garching. This has been stopped now, and only calibration data are pipeline-processed by QC Garching.
All the raw data taken on an astronomical calibrator are processed by the pipeline. In some cases, the automatic pipeline can not reduced the raw files, in this case no pipeline products is produced.
A set of raw data should includes:
The following table shows some of the main keywords for the different raw files
Two different types of files carry a DPR CATG=CALIB :
All the files with a DPR CATG=CALIB are not proprietary and will be available from the science archive .
The science data (DPR CATG=SCIENCE) are not processed by QC but the raw files are available from the archive . The master products to be associated with the science files can be obtained using the calselector option.
The raw data taken with the VLTI are processed twice :
The pipeline delivers visibilities for each baseline and each spectral bands for the astronomical calibrators. If the object is in the calibrator catalog, a Transfer Function is also calculated. These products are used to assess the quality of the calibrator observation and to certify if they could be used to be further associated to the science data.
The pipeline supported modes for P80 are the data taken with the standard observation template : Obs_Std. The following table shows the type of files and the pipeline recipes used to reduce them. More details on the pipeline recipes can be found here. More on the file associations can be found here.
The delivered products are in format of ASCII files in the logs directory of the Data Package (association files, pipeline and association logs), and FITS files.