Visualization of the EMIR and Backends setup

JoaquĆ­n SG. 2020/11/09

We have developed a Python task for plotting a scheme of the EMIR and backend configuration of an observation. This observation could be the last scan accepted by the system (see Visualization of the current scan), or a test scan sent in "set doSubmit no" mode while preparing future observations in PaKo (see Preparatory visualization of a PaKo setup). The plot allows a fast check of the EMIR covered frequencies, tunning limits - complaining if we are out of the allowed range-, IF distribution, and backend configuration. For the backends, it is displayed the exact frequency limits of each band unit, including Vespa real bandwidths and offsets, and channel resolution.

Note: Since the information is taken from the .xml files sent by PaKo to the NCS, the data displayed are the commanded configuration, which is not necessarily the actual configuration if there is any problem in the system.

Visualization of the current scan

The bash script runs a loop executing the Python that generates the last accepted scan's EMIR configuration plot, accessible in this webpage, together with bookkeeping plots for each scan. This bash script should be started by the operator in the following way:

$ slogin mrt@mrt-lx1
$ cd /mrt/ncs/monitor/jqtest
$ ./

It can be stopped and restarted at any moment, but the scans executed while not running will not be automatically archived. In case it is not working, please, ask the operator to restart it.

The following plot (description below the figure) is an example of the output graph for this PaKo setup:

PAKO> RECEIVER E090 12CO(1-0) 115.271 UO /HOR UO /VER UO
PAKO> RECEIVER E230 12CO(2-1) 230.538 UI /HOR UI /VER UI
PAKO> BACKEND VESPA 1 0.040 120 0 E090 Horiz UO   
PAKO> BACKEND VESPA 2 0.040 120 0 E090 Verti UO
PAKO> BACKEND VESPA 3 0.040 120 0 E230 Horiz UI
PAKO> BACKEND VESPA 4 0.040 120 0 E230 Verti UI


For each EMIR band in use, we plot the upper and lower sidebands in grey, with rest frequency values (in GHz) for each subband center and boundary limits (using the FTS-wide coverage), and local oscillator. In blue are depicted the name and rest frequency of the line tunned, tunning subband name, local oscillator frequency corrected only for the source velocity, and the 4 IF assignation done by the observer (the automatic IF assignation for IF's 5 to 8 is shown in grey). Above, in red, we plot the band tunning limits for the tunning sideband selected (lower or upper) as described in the Emir for Astronomers table ("the centers of the outer, respectively inner, 4GHz IF bands"), together with the frequency band limit and the frequency limits of the local oscillator (with an arrow pointing towards the range of allowed frequencies). Below, we plot the backend assignation, showing for each unit the number, polarization (same color for each polarization in different backends), frequency extension of the unit (in GHz), and resolution (in parenthesis, in MHz).

For Vespa, we take into account the frequency offsets if defined, and the real bandwidth (slightly different from the defined one), as shown in the following figure:

PAKO> RECEIVER E150 CS(3-2) 146.969 LI /HOR LI /VER LI
PAKO> RECEIVER E330 13CO(3-2) 330.588 LI /HOR LI /VER LI
PAKO> BACKEND VESPA 1 0.020 60 +230 E150 Horiz LI   
PAKO> BACKEND VESPA 2 0.020 60 +230 E150 Verti LI
PAKO> BACKEND VESPA 3 0.020 60 -230 E150 Horiz LI
PAKO> BACKEND VESPA 4 0.020 60 -230 E150 Verti LI

E0 E2

Also for Vespa, we do show if it is working on parallel or polarimetry modes.

The program warns when we override the EMIR tuning limits, plotting the receiver tuning setup info in red instead than in blue, plus a "out of range!" message, as we can see in the following example:


E3 out

Note: since this check is done by comparing local oscillator limit with the commanded value corrected only by the source velocity and not by the Earth movement relative to the LSR and source orientation, at frequencies close to the limit we would have a slight uncertainty, but of a few tenths of MHz maximum.

Preparatory visualization of a PaKo setup

We can also get this EMIR-backend configuration scheme plot for testing a PaKo setup when preparing an observation, that is, without sending any scan to the observing queue (= with the "set doSubmit no" option activated). For that purpose, we have another program version called, which reads the .xml generated by PaKo but not sent to the system. It also can be used during actual observations in case you want to check the configuration of the last scan sent to the queue instead of the configuration of the current/last scan described in the previous section.

For using it from any observation account, after sending an observation with the "set doSubmit no" option if needed, execute in the pako directory:

$ useNCS

It will open a window with the configuration scheme.

EmirConfigPlots (last edited 2021-05-20 04:13:19 by santiago)