H1 ETMY HWS new laser source fine tuning alignment, imaging and mode-matching.

Thursday ETMY HWS notes

 

0934 – at etmy. Going to work on imaging first using the sharpness of the baffle shadow as a guide.

0940 – removed hartmann plate. Ready to take images.

 

Ruler, GPS time of image

77mm, 1255365740

44mm, 1255365872

100mm, 1255365916

150mm, 1255365961

191mm, 1255366027

230mm, 1255366071

 

0953 – back to corner station to analyze the data

1032 – not 100% clear but minimum looks to be at 90mm, with uncertainty of +/- 10mm.

So put it camera at 100mm to account for additional 10mm between Hartmann plate and the CCD. Leaves an uncertainty of ~ +/-6m from the test mass.

1117 – back at ETMY

1122 – FC/APC coupler installed. No change in the amount of power on the CCD

• HWS moved to the 100mm mark on ruler and bolted down

1127 – Using the pico mirro furthest from the periscope, I can move the beam around. When intensity is centered on the shadow, I can see clipping in the top left hand corner which gets much worse when I move it that way. Effect is asymmetric. I Do not see the same effect when moving it in the opposite direction.

1200 – 2.70units to 3.23units on translation stage

1210 - Back to 3.0units – 1255374607 to make a smaller beam. Trying to cover a range of 5mm on CCD = 110mm on ETM

1213 – Hartmann plate reinstalled.

1214 – door on

1215 – running HWS code

SSF = 2Hz, ----

1219 – Front end is down

• Beam moved a lot when we tilted the optic – recheck imaging

_- Smaller beam helps a lot in making return beam look better

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1344 – Back from lunch

Going to redo imaging

----

YAW0 = 128, YAW1 = 138

Z = 100mm

Dx = 5.05pixels

Z = 140mm

DX = 3.343

Z = 180mm

DX = 1.963

Z = 220mm

DX = 0.703

Z = 230mm

DX = 0.21

Z = 260mm

DX = -0.831

Zero crossing = 236.5

With plate = 246.5;

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1424 - New position – 1255382646

1505 – Going to clean fiber laser end.

• It doesn’t couple well into patch cable. I think it’s dirty

1525 – Fiber cleaning only helped a tiny bit

• Going back to just 50/50 coupler
• Some realignment required on input 

1530 - 1255386598 – Intensity distribution

1536 – added iris to front of CCD

1537 – reinstalling Hartmann plate

(Z = 245mm on ruler)

1539 – Hartmann plate is on

• Restarting Hartmann code
• Frame rate = 2Hz, 261 centroids, peak value = 1460

1544  - Frame rate = 1Hz, 262 centroids, peak value = 2840

1255387575 – ETMY RH set from 0.8W to 4.8W

1547 – Changed ETMY magnification to 22.8x

See if can hook up remote control tomorrow.

How robust is launcher to misalignment/bumping?