Dynamic LST Validation (NEW!)

We have added a new tab to the scheduling block (SB), "Dynamic LST Validation" (aka Block Checker Tool). This new built-in tool will allow observers to check their observations for a specified LST start range and several defined parameters.

Important Notes:

This new tool is a work in progress. Please contact the NRAO Science Helpdesk if you encounter any issues, discrepancies, or you see a message with "unknown" severity.

The NRAO staff will continue to check SBs before approving for observation.

Currently, the tool will not check or flag the following parameters:

antenna shadowing (applicable to D and C-configuration)

However, antenna shadowing information remains present on the Static Reports tab in the Summary Report table near the bottom. You will need to adjust the assumed LST start time to check when/if there are shadowed antennas.

antenna wraps (CW, CCW, or no preference)

We are working on optimizing this for less confusion. For now, ask us for help in determining which antenna wrap to use if you are unsure.

Dynamic LST Validation Parameters

Starting Conditions

The following are editable starting conditions.

LST Start Range	To use the same LST start range from the Information tab, select the "Get LST From Info Tab" button. Any changes made to the LST start range on the Dynamic LST Validation tab do not propagate to the Information tab. If you determine a new LST start range is more suitable while you are working in the Dynamic LST Validation tab, then you will need to change the LST start range in the Information tab.
LST Step	This will allow you to step through the defined LST start range in increments of 5, 10, 15, 20, 25, or 30 minutes. The default is 5 minutes, since the LST start range can be set in 5 minute increments.
Assumed Antenna Starting Direction	Azimuth This will help you determine if you have enough slew and on source time for the first calibrator scan, i.e., reference pointing, flux, bandpass, complex gain calibrator, etc.. The default starting AZ position is 225.0d. If the starting azimuth of the first source is rising (AZ = ~85d), then set the assumed starting AZ position to 445.0d. If the starting azimuth of the first source is setting (AZ= ~275d), then set the assumed starting AZ position to -85.0d. Elevation You may also set an assumed starting elevation position. The default starting position of 35.0d is usually sufficient.

Evaluator Settings

The following are editable evaluator settings.

Elevation Limits	Low EL Limits 10.0d is the recommended lower limit. 8.0d is the hard limit of the VLA antennas. When possible, please avoid elevations less than 10.0d. For D and C-configuration, you may want to consider a more conservative lower elevation limit to avoid antenna shadowing. High EL Limits 80.0d is the recommended upper limit for high frequency observations (Ku/K/Ka/Q-band) 85.0d is the recommended upper limit for low frequency observations (4/P/L/S/C/X-band)
Time On Source Minimum	You may edit the recommended default settings for your observation.

If you wish to reset the evaluators to the default settings, select "Reset to VLA Defaults". Note, the starting conditions will not be reset.

Running the Block Checker

Once you are satisfied with your starting conditions and evaluator settings, select "Start Dynamic LST Validation".

The results may be grouped by evaluator, severity, or all. A "Show All" or "Hide All" results option is also available.

This can be helpful when there are many messages and only want to focus on a particular evaluator or severity. The messages in the table(s) may be sorted by selecting the top row of each column, i.e., by scan name, scan number, etc..

In addition to the editable evaluator parameters, you may see addition evaluator messages if they have been flagged in your SB. If they do not appear, then they were not used. This is likely ok. It is also ok if after you select "Start Dynamic LST Validation", you see the info message: "No Messages to display. Scheduling Block looks good."

Message Types

Evaluators

Setup Scan	messages will appear if, initial attenuator setup scans for any resource is missing and, requantizer gain setup scans are missing for 3-bit or mixed-mode 3/8-bit resources.
Scan Time Type	messages will appear if the prohibited time types are found: Duration (UT) On Source (UT) On Source (LST)
Flux Calibrator	message will appear if 3C295 is used as the flux density scale calibrator. 3C295 is not recommended for flux density scale calibration since it is highly resolved and CASA does not have a model.
Scan Intent	messages will appear if, non-standard scan intent is in use, i.e., Determine Autophase, setup intent is used with other scan intents.
Scan Flags	Three types of warnings may appear under this evaluator: indicates a special mode for observing is in use and may not be what was intended. If intended, then it may be ignored. indicates observing modes specific to VLBI (phased array), pulsar mode, or eLWA observations are in use. This may not be what was intended. If intended, then it may be ignored. indicates a prohibited mode is in use, i.e., Over the Top.
Scan Duration - Maximum	will appear for all scans and all LST start times which exceed the default scan duration maximum of 15 minutes. If no scans exceed a maximum duration of 15 min, then no warning messages will appear.
Source Elevation - Maximum	will appear for all scans and all LST start times which exceed the defined elevation maximum. If no scans exceed the maximum defined elevation, then no warnings will appear.
Source Elevation - Minimum	will appear for all scans and all LST start times which exceed the defined elevation minimum. If no scans are below the minimum defined elevation, then no warnings will appear.
Time On Source - Minimum	will appear for all scans and all LST start times which exceed the defined time on source minimum set in the table. If no scans are below the time on source minimums, then no warnings will appear.