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Knowledgebase : Historical Articles
Yes, there are three main issues to be aware of for Cycle 0 data: * A major refactor of the calibration table format and functionality took place between CASA 3.3 and CASA 3.4. Calibration tables created in CASA 3.3 (and earlier) cannot be used in CAS...
In order to tell for sure which version of CASA was used for calibration and imaging, check the data reduction script. The data were calibrated and imaged in, for example, CASA 3.4 if the script contains the line: if re.search('^3.4', casadef.casa_versio...
Cycle 0 data reduction was done using CASA versions 3.3 and 3.4, which use the Butler-JPL-Horizons 2010 models to set the flux model for solar system objects.  The fluxes of science targets were then bootstrapped from these solar system object measurement...
ALMA Cycle 0 PI or Science Verification data may have been reduced in an earlier version of CASA. In this case, the scripts that were provided in the original data delivery will most likely not work with later versions of CASA (see the Knowledgebase artic...
For a short time during 2014, users running a version of Java 7 with an update number of 51 or higher found that the OT would not start because of the following security exception: "Missing required Permissions manifest attribute in main jar". This prob...
Certain types of observing program require special attention by an ALMA Staff Phase-2 Group (P2G) member after the Scheduling Blocks (SBs) have been generated, in order to ensure successful execution at the telescope and the highest possible quality data....
The symptom: On windows machines (particularly it seems, in EA-ARC), the OT may not open - often it simply closes itself down, before even the basic startup procedure. If the tarball version of the OT is run, the output of the /users//.almaot/...
In CASA versions BEFORE 4.3 there is a problem with libxml on some Linux distributions other than RHEL 5 and 6, e.g. Ubuntu 13 and Fedora 20. The libxml version shipped with CASA does not work with other system libraries. You will need to do the following...
Channel (spectral or velocity) averaging is done by the task split, while the cvel task only interpolates the data onto a new frequency grid. To achieve both channel averaging and to move the data to a new frequency grid, one must combine split and cvel. ...
The OT does not allow users to specify a minimum angular resolution (i.e. restrict the range of angular resolutions such that a source will definitely be unresolved) because this considerably narrows the range of configurations that can be used, and compl...
For ALMA Cycles 0-4 data packages, the images that are included in the data delivery package may not include all spectral windows, or all channels, or all targets that were observed as part of the science program. These images are meant to be representati...
Data from the correlator, together with monitor and weather data, are sent via dedicated optical fiber links (1-10 Gbit/s) to the OSF, where they are archived. A peak data rate of 66.6 MB/s can be sustained for short periods of time, i.e. days. This peak ...
Cycle 0 data was processed by ALMA science staff using CASA, with scripts that reflect the best practices in ALMA data reduction. However, improvements and bug fixes to CASA are made over time, and users may wish to reprocess their data with a more recent...