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Science target overview

description of what the iras source is.

ALMA data description

This release of ALMA data is for observations taken in the Band 9 (602-720 GHz) using the FDM (Frequency Division Mode) setup. The observations target the CO 6-5 spectral line at a frequency of 691.473 GHz using four spectral windows of 1.875 GHz (813 km/s) wide with 3840 channels each. The channel width is 0.488 MHz, and because the observations use Hanning smoothing, the actual spectral resolution, and so the velocity resolution, is twice the actual channel spacing.

The data were taken during April 16 and 17, 2012. Four datasets are presented here and some of them have pre-transit observations of the target source, while other pos-transit. Each dataset lasts for 2.3 hours, including calibrations. The names of the datasets are

  • uid___A002_X3d4118_X39b
  • uid___A002_X3d55cb_X575
  • uid___A002_X3d55cb_Xb50
  • uid___A002_X3d55cb_X90c

The array was set in the extended configuration for the Early Science Cycle 0. The expected angular resolution at the CO 6-5 frequency is about 0.2 arcsec.

Download the data

To download all the data, follow one of the next links:

North America


East Asia

You will download gzipped tar files that contains the following directories:

IRAS16293_Band9_UnCalibratedMSandTablesForReduction - The file contains the raw data files in ALMA Science Data Model (ASDM) format already converted into CASA Measurement Sets (MS) using importasdm inside CASA. We also provide the tables that are needed to calibrate the data.

IRAS16293_Band9_CalibratedData - The fully-calibrated u-v data, ready for imaging.

IRAS16293_Band9_ReferenceImages - The final continuum and spectral line images.

Depending on how you want to proceed to work with the IRAS16293 data, download the file that corresponds.

NOTE: CASA 3.3 or later is required to follow this guide. For more information on obtaining the latest version of CASA, see

IRAS16293 data tutorials

This tutorial has been split into two parts - calibration and imaging:

1) IRAS16293 Band9 - Calibration : This section of the tutorial steps you through inspection and calibration of the basic visibility (u-v) data. To complete this part, you will need the data in the first directory: IRAS16293_Band9_UnCalibratedMSandTablesForReduction.

2) IRAS16293 Band9 - Imaging : This part of the tutorial focuses on constructing images from the calibrated visibility data. If you wish to skip calibration and proceed directly to this part of the tutorial, you will need the fully-calibrated visibility data in the IRAS16293_Band9_CalibratedData directory.

We also provide the final continuum and spectral line images in the IRAS16293_Band9_ReferenceImages directory.

How to Use A CASA Guide

For tips on using CASA and ways CASA can be run, see EVLA_Spectral_Line_Calibration_IRC+10216#How_to_Use_This_casaguide page.

To learn how to extract executable Python scripts from the tutorial, see Extracting_scripts_from_these_tutorials.

Within the guides:

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Last checked on CASA Version 3.0.0 (r9860).