Guide To Processing ALMA Data for Cycle 0: Difference between revisions

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# [http://almascience.eso.org/alma-data/archive Europe]
# [http://almascience.eso.org/alma-data/archive Europe]
# [http://almascience.nao.ac.jp/alma-data/archive East Asia]
# [http://almascience.nao.ac.jp/alma-data/archive East Asia]
Describe here the issue of raw data vs. "project view" and how to avoid multiple downloads
== Overview of Delivered Data and Products ==
Describe here the data products and scripts
CASA 3.4 vs. 4.2
Typical approach: Use the delivered calibrated data, and user only needs to do self-cal and imaging.
For those who want to tune the calibration: go through the steps
Note, the scripts refers to the combined data set, so first step is to combine the 3 cal executions:
The delivered data has cal steps 0-5 (a priori) completed.  User

Revision as of 10:16, 26 February 2014

Processing ALMA Data

This guide describes steps that you can use to process ALMA data, beginning with locating and downloading your data from the public archive, to making science-ready images.

We will use a sample data set from ALMA Cycle 0 in this guide. Data for Cycle 1 and beyond will be delivered in a different format and will require a separate guide.

About the Sample Data : H2D+ in TW Hya

The data for this example comes from ALMA Project 2011.0.00340.S, "Searching for H2D+ in the disk of TW Hya v1.5", for which the PI is Chunhua Qi. Part of the data for this project has been published in Qi et al. 2013.

The observation was set up with two spectral windows ... frequency/bandwidth/chan spacing/etc

The project required three executions of the scheduling block. explain ...

Prerequisites : Computing Requirements

ALMA data sets can be very large and require significant computing resources for efficient processing. The data set used in this example begins with a download of 176 GB of data files. A description of recommended computing resources is given here. Those who do not have sufficient computing power may wish to arrange a visit to one of the ALMA Regional Centers (ARCs) to use the computing facilities at these sites. To arrange a visit to an ARC, submit a ticket to the ALMA Helpdesk.

Getting the Data: The ALMA Data Archive

The ALMA data archive is part of the ALMA Science Portal. A copy of the archive is stored at each of the ARCs, and you can connect to the nearest archive through these links:

  1. North America
  2. Europe
  3. East Asia

Describe here the issue of raw data vs. "project view" and how to avoid multiple downloads

Overview of Delivered Data and Products

Describe here the data products and scripts

CASA 3.4 vs. 4.2

Typical approach: Use the delivered calibrated data, and user only needs to do self-cal and imaging.

For those who want to tune the calibration: go through the steps

Note, the scripts refers to the combined data set, so first step is to combine the 3 cal executions:


The delivered data has cal steps 0-5 (a priori) completed. User