anthony.sanchez@LIGO.ORG - posted 17:52, Tuesday 28 May 2024 - last comment - 17:36, Friday 14 June 2024(78105)
PCAL End Station Measurement
Today Dripta and I went to EY and did what would have previously call a standard ES measurement with PS4.
And We also employed the new End Station procedure.
Details and analysis ccoming in a comment to this alog.
A PCAL ENDY Station Measurement was done on May, the PCAL team (Dripta B. & Tony S.) went to ENDY with Working Standard Hanford aka WSH(PS4) and took two End station measurements to verify that the results were consistent with each other. One with our previous version of T1500062-V16 procedure and another with T1500062-V17.
The ENDY Station Measurements was carried out mostly according to the procedures outlined in Document LIGO-T1500062-v16 & v17, Pcal End Station Power Sensor Responsivity Ratio Measurements: Procedures and Log.
Measurement Log
First thing we did was take a picture of the beam spot before anything is touched!
Martel:
Martel Voltage source applies voltage into the PCAL Chassis's Input 1 channel. We record the GPStimes that a -4.000V, -2.000V and a 0.000V voltage was applied to the Channel. This can be seen in Martel_Voltage_Test.png . We also did a measurement of the Martel's voltages in the PCAL lab to calculate the ADC conversion factor, which is included on the above document.
Plots while the Working Standard(PS4) is in the Transmitter Module during Inner beam being blocked, then the outer beam being block, followed by the background measurment: WS_at_TX.png.
The Inner, outer, and background measurement while WS in the Receiver Module: WS_at_RX.png.
The Inner, outer, and background measurement while RX Sphere is in the RX enclosure, which is our nominal set up without the WS in the beam path at all.: TX_RX.png.
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The New Document has a different order of measurements that are taken and are taken in a different way.
We placed the Working Standard (PS4) in the path of the INNER Beam at the TX module.
Then the Working Standard (PS4) in the path of the OUTER Beam at the TX module.
A background measurement.
Then we take the Working Standard and put it in the RX module to get the INNER Beam.
Then the OUTTER Beam in the RX Module.
And a Background.
This is where things get different....
We remove the beam block and give the Working Standard Both Inner and Outer Beams at the SAME TIME while it's at the RX module.
We also put the RX sphere back to the RX module and put both beams on it at the same time. Like nominal opperation when the PCAL lines are turned off.
Then we take a background.
This was repeated ~10 mins later because we wanted to see if there is any time dependent variations.
The last picture is of the Beam spots after we had finished the measurement.
Old procedure measurement results : "rhoR_prime": 10565.2
New Procedure Measurement: rhoR_prime : 10571.1. This 5 hop difference is well within our uncertainty .
second New Procedure rhoR_prime 10574.3, was off by less than 3hops ,well within uncertainty.
Preliminary analysis suggests that discrepancy in rhoRprime calculated via two methods is allowed within the uncertainty.
All of this data and Analysis has been commited to the SVN or GIT:
https://svn.ligo.caltech.edu/svn/aligocalibration/trunk/Projects/PhotonCalibrator/measurements/LHO_ENDY/
Obligitory BackFront PS4/PS5 Responsivity Ratio:
PCAL Lab Responsivity Ratio Measurement:
A WSH/GS (PS4/PS5)BF Responsivity Ratio measurement was ran, analyzed, and pushed to the SVN.
PS4PS5_alphatrends.pdf to show that the recent changes to the lab have not impacted the Lab measurements
This adventure has been brought to you by Dripta B. & Tony S.