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As summarised in an article about the status of Cycle 1 observations [1] available at the Science Portal, about 300 hours of high priority Cycle 1 projects may be carried over to Cycle 2. Therefore, a rough estimate is that 1700 hours (2000-300) will b...
The user-specified "Largest Angular Structure" (LAS) determines whether a project needs observations using compact array configurations, including the ACA (see KB article \"How can I request Atacama Compact Array (ACA) observation time in Cycle 2?\" [1...
The easiest way to calculate the spectral coverage of one or more SPWs in different freqeuncy reference frames is by using plotms or viewer. For a measurement set, plotms will plot data as a function of frequency using the reference frame selected in t...
A small fraction of Cycle 0 data sets have been found to be impacted by a bug in the CASA 3.4 task 'tflagdata'. When 'tflagdata' in CASA 3.4 was used to flag SHADOWED antennas, instead the SHADOWING antennas were flagged. The impact of this bug on deli...
The ALMA calibrator database will eventually be available via a web form. In the meantime, you can query the ALMA calibrator database from the OT in this way: - Open up the OT and create a Science Goal (or use an existing Science Goal) - Go to the "Calib...
The total data rate in an observation is an estimate of the total instantaneous data rate summed over all basebands based on the current parameter settings (see Sec. 6.4.4.3 of the OT Reference Manual [1]and Sec. 6.2.4.2 of the OT User Manual [2] regar...
How can I update Cycle 0 absolute fluxes to the Butler-JPL-Horizons 2012 model standards? 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 simobserve task reads the antenna locations from a configuration file specified by the parameter "antennalist." This is a plain text file which lists x, y, and z coordinates for each antenna as well as antenna diameter and pad name. Several antenna...
You can load multiple sources into a Science Goal (for single pointings per source only) using an ASCII file from your local disk. For each target, the text file must contain a list of comma-separated entries in the following order: Source Name, RA(se...
You can create your own copy of the Observatories table by taking it from directory data/geodetic in your CASA distribution and then editing your copy with task "browsetable" in CASA. Once you have your own copy, e.g. in directory "/home/myself...
In spectral scans generated by the OT there is no overlap between tunings for FDM modes, whereas there is (effectively) a small overlap for the TDM mode as the spectral windows are assumed to be only 1875 MHz wide, even though the whole 2000 MHz are actua...
As of Cycle 1, the order ALMA is hoping to add new bands is as follows: * Bands 4 and 8 will be available for Cycle 2. * Band 10 is undergoing testing in Chile. It will not be available in Cycle 2 but could be available in following Cycles. * B...
Installations of Java since version 7 Update 51 will probably not allow the Web Start version of the Observing Tool to start by default. Clicking on "Details" in the error dialogue will show the following: "Missing required Permissions manifest attribu...
Individual targets that are larger than 1/3 of the Field of View (FOV) of the 12-m Array will require a Nyquist sampled mosaic to obtain uniform sensitivity across the field due to the sensitivity fall-off towards the edges of the primary beam. This can b...
If a user selects the "Choose a Solar System Object" option (SSO) in the OT Field Setup, the OT sets the position to RA=0deg, Dec=0deg. However the OT time estimate depends on the declination of the observed source, as described in Section 9.1.2. o...
RUNNING THE WEB START OT ON A MAC If the Observing Tool is started from a Mac, many users who are running Lion, Mountain Lion or Mavericks may find that clicking on the Web Start icon in a browser does not, as used to be the case, start the OT automatic...
Since the Cycle 2 Call for Proposals on October 24, 2013, there have been a number of items of potential interest to proposers which are not completely clarified in the main call materials. These items may affect how users write their proposals or set ...
The absolute position accuracy of an ALMA image will be limited by the accuracy of the phase calibrator position and the quality of the phase transfer during the observations. The latter depends on the weather conditions, the angle between the phase ca...
Upon its first successful submission, a proposal receives a unique code adhering to a standard format. The format of the proposal code is as follows: YYYY.C.NNNNN.Z. Here, "YYYY" denotes the year, "C" identifies the cycle during that year, "NNNNN" is a...
Messages like SEVERE setjy Leap second table TAI_UTC seems out-of-date. SEVERE setjy Until table is updated (see aips++ manager) times and coordinates SEVERE setjy derived from UTC could be wrong by 1s or more. on Linux installations of CASA in...
Both in CASA 4.1 and 4.2, there is a problem with libxml2 on some Linux distributions other than RHEL 5 such as Ubuntu 13 and Fedora 17. The libxml2 version shipped with CASA does not work with the other system libraries. You need to do the following ...
This is to notify all CASA users that a bug was dicovered in the code underlying the field selection mechanism in the _"_clean_"_ task. The bug is present in CASA 3.4, 4.0, and 4.1 and affects the flux scaling and restoring beam calculations in the tas...
The time estimates for Cycle 2 are calculated in a different way to Cycle 1 and this has lead to significant differences between the time estimates calculated for each cycle. The main difference is that the integration and cycle times for each calibrat...
Many users will notice that the overheads for projects that require multiple tunings (multiple source redshifts or spectral scans) are very high. The problem is basically that each SB execution in multi-tuning mode must observe the calibrators (amplitu...
For single or dual polarisation spectral line Science Goals, the user-defined calibration strategy that is suggested by the OT will cause an error in the time estimate. For unknown reasons, Single Continuum, Spectral scan and Full polarisation Science ...
If the data rate computed for your Science Goal setup by the OT exceeds 12 MB/s (or twice the average data rate that ALMA can handle) the OT will issue a warning, and you will be asked to justify it in the Technical Justification. This warning will *not* ...
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 rec...
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