Processing SMA Data
1.2 m Telescopes

SMA Data Calibration with MIR

MIR Introduction

MIR (Millimeter Interferometer Reduction) is an IDL based software package. Originally developed at Caltech for use at OVRO, it has been adapted for the reading and calibration (but not imaging) of SMA data. MIR is currently the recommended software for SMA data calibration. Be aware that IDL requires a license.

MIR tips for new users
Official MIR Cookbook

Data calibration

See the effects of each calibration step at MIR Calibration Steps Explained.


1. SWARM data
2. ASIC data

Polarization data

Calibrating Dual Receiver Polarization Data [pdf]

Questions and Troubleshooting

Find more data reduction Q&A at SMA Data FAQ

You can also find fixes for specific issues between 2005 and 2010 at SMA Data Errors and MIR Fixes.

MIR on the RTDC computers

MIR is available on all RTDC machines. Simply type idl in a terminal. Version 8.3 is the default, although IDL 6.2 is available by typing idl6.

IDL is single threaded and has considerable memory requirements - typically 2.5-3 x the size of the data. For large SWARM datasets you may to rechunk, or only read in a single receiver or sideband at a time.

MIR batch jobs and pipeline

We are developing a MIR based pipeline for the calibration of SMA data. This is an ongoing project so you can expect updates to this section.

You can run any MIR script as a batch job from the command line. The example below shows how to run the calibration script calibratesmaswarm. Note that this script is for illustration purposes only and should not be used to calibrate real data . It requires four arguments: the path to the data, the data directory name, a rechunk flag, and an error flag. Here the output is written the screen and a log file.

$ idl -e calibratesmaswarm -args /sma/data/science/ 170101_12:01:01 1 0 | tee script_`date +%y%m%d`.log

When running batch jobs you can force any MIR task to accept the default options rather than waiting for user input at the prompt by using the /nowait flag.

Note that the script names must be consistent in order to run batch jobs. In this example, the first line of the script is pro testscript, the name of the file is, and it is called on the command line with idl -e testscript.

Getting help

You can email for general help. Or contact the MIR project scientist, Dr. Qi, at with detailed questions.