NikoL, Dimitri Estevez (Virgo), SudarshanK (remotely), RickS
This morning, we calibrated the Yend Pcal readback channels using the working standard (WSH) that we had delivered to Yend yesterday afternoon and left powered up overnight.
We encountered a couple of software issues related to the updates to calculate the force coefficients in the frontend, but we were able to complete the measurements.
The power sensor coefficients calculated today were very close to the values we calculated from the measurements made on December 13.
| Sensor | Dec. 13 | Jan. 15 | ratio (new/old) |
|---|---|---|---|
| Tx (V/V) | -0.480810 | -0.480448 | 0.99925 |
| Rx (V/V) | -0.715832 | -0.715410 | 0.99941 |
We decided to go ahead and switch to using the force coefficients calculated in the frontend (using JeffK's new code). We updated the epics values using the data from our Dec. 13th measurement and captured in the .txt file attached in that entry. We "put" the values into the epics records by just copying and pasting the text in the lho_yend_pcal_epics_created-20190115.txt file attached to this entry and in the SVN at
/ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O3/H1/Results/CALCS_FE/yend_pcal_epics_created-20190115.txt
The new Pcal power sensor calibration values (N/V) and comparisons with the previous values are:
| Force coeff. | New | Prev. | ratio (new/old) |
|---|---|---|---|
| Tx (N/V) | 1.5049e-9 | 1.5160e-9 | 0.9927 |
| Rx (N/V) | 1.0223e-9 | 1.0475e-9 | 0.9759 |
We checked the beam spot locations on the Rx power sensor aperture. The beams are reasonably well centered; both beams are incident on the integrating sphere in the attached photo.
Notes from today's Pcal calibration work attached below.
One of the end station calibration procedures involves using the Martel voltage supplier at both the end station and the LSB lab to calibrate voltage measurements. The output from the LSB lab measurements is:
|
WSH |
Input (from Martel) [V] |
Output (from Keithley) [V] |
|
-4 |
-4.0001 |
|
|
-2 |
-2.0001 |
|
|
-1 |
-1.0001 |
|
|
0 |
0.000008 |
|
|
1 |
1.00001 |
|
|
2 |
2.0001 |
|
|
4 |
4.0001 |
The attached text file to the main entry, called out stored in the CalSVN repo as /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O3/H1/Results/CALCS_FE/lho_yend_pcal_epics_created-20190115.txt *had* had a bug in it -- see LHO aLOG 46472. After finding the bug, the contents of the file were replaced in the above attachment, and it was run and installed in the front-end. For posterity, I've saved the file as a new name in the Cal repo: /ligo/svncommon/CalSVN/aligocalibration/trunk/Runs/O3/H1/Results/CALCS_FE/lho_yend_pcal_epics_created-20190116.txt