Karl G. Jansky VLA Tutorials

Introduction

The Karl G. Jansky Very Large Array (VLA) Tutorials are meant to guide the observer through some common types of data analysis, using example datasets, and including explanations of the individual steps. These analyses will be broadly applicable to many VLA data sets.

If you are new to CASA, you may start with

Getting Started in CASA

VLA Data Reduction Tutorials

Carbon Star IRC+10216: high frequency (36GHz), spectral line data reduction (CASA 4.6)

IRC+10216 Tutorial

This tutorial requires to download a dataset 1.1GB in size

Calibrate and make image cubes of the line emission from this asymptotic giant branch star. This is a high-frequency VLA dataset. Includes:

Inspecting data; basic flagging & calibration

Subtracting continuum emission

Imaging the spectral lines

Imaging the continuum

Image analysis

Self-calibration

Supernova Remnant 3C391: 6cm Polarimetry and Continuum Imaging, Mosaicking (CASA 4.6)

3C391 Tutorial

This tutorial requires to download a dataset 3.1GB in size

Calibrate VLA full polarization data, image a mosaic of the region in full Stokes and create a spectral index map. Includes:

Inspecting data; basic flagging

Calibration

Image Analysis and Manipulation

Polarization Imaging

Spectral Index imaging

Self-calibration

P-band continuum imaging data reduction tutorial (CASA 4.6)

P-band Tutorial

This tutorial requires to download a dataset 21GB in size

This low-frequency VLA tutorial for the observation of a giant radio remnant focuses on low frequency wide-fractional-bandwidth data in the sub GHz regime . This includes:

Basic flagging and evaluation

Automatic RFI Excision

Ionospheric Calibration

Self - Calibration

VLA Topical Guides

FLagging VLA Data in CASA

Topical Guide: Flagging VLA Data (CASA 4.5.2)

This tutorial requires to download a dataset 4.9GB in size

This tutorial describes different flagging techniques, including: Calibrate and make image cubes of the line emission from this asymptotic giant branch star. This is a high-frequency VLA dataset. Includes:

Identifying Problematic Antennas from the Operator Logs

Online Flags (shadowing, zeroes, quacking, flagmanager, Hanning smoothing)

Automatic RFI excision (TFCrop, RFlag)

Interactive Flagging

Flagging Summary & Report

Imaging VLA Data in CASA

Topical Guide: Imaging VLA Data (CASA 4.6)

This tutorial requires to download a dataset 1.2GB in size

The Imaging topical guide shows annotated examples of different imaging techniques that are applicable to different science applications. This tutorial includes:

An Introduction to the CLEAN algorithm, data and imaging weights, primary and synthesized beams

Clean Output Images

Dirty Image, Regular CLEAN & RMS Noise, CLEAN with different Weights

Multi-Scale CLEAN

Multi-Scale, Wide-Field CLEAN (w-projection)

Multi-Scale, Multi-Term Frequency Synthesis

Multi-Scale, Multi-Term Frequency, Widefield CLEAN

Imaging Outlier Fields

Primary Beam Correction

Imaging Spectral Cubes, Beam per Plane

Image Header, Image Conversion

Correcting for a Spectral Index in Bandpass Calibration

Topical Guide: Correcting for a Spectral Index in Bandpass Calibration (CASA 4.5.2)

This tutorial requires to download a dataset 3.4GB in size

This tutorial explains how to obtain a bandpass solution when the bandpass calibrator is a source with an unknown spectral index. This is typically encountered at high frequency observations, where the standard VLA flux density calibrators are too weak for high signal-to-noise bandpass solutions.