Poster Abstract

P10.41 Joe Masters (National Radio Astronomy Observatory (NRAO))

Theme: Data processing pipelines

Pipeline Calibration and Imaging for the ALMA Observatory

The Atacama Large Millimeter/submillimeter Array (ALMA) is a large radio observatory in northern Chile. The ALMA data processing pipeline, written in Python and built largely upon the Common Astronomy Software Applications package (CASA), produces calibrated measurement sets, images and supporting products. This same pipeline is used to calibrate data from the Karl G. Jansky Very Large Array as well as the Nobeyama Radio Observatory. Here we describe the pipeline as it is used by ALMA.

Descriptions of the key tasks, heuristics, processing recipes and products are presented. Pipeline tasks are built upon CASA tasks and tools. A task can be thought of as a mini-application or atomic feature within a larger workflow. For example, import, export and each calibration step are considered as separate tasks. The pipeline heuristics contain all of the calibration and imaging decisions that are driven by the input data. The recipes define the dataflow from raw data to final calibration, imaging and summary products.

The pipeline is developed by an international consortium of scientists and software developers based at the National Radio Astronomical Observatory (NRAO), the European Southern Observatory (ESO), and the National Astronomical Observatory of Japan (NAOJ) and the Joint ALMA Observatory (JAO).