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New Laser Calibration Status. New Laser vs Old Laser Safety Pond Data Outrigger Data How to Combine?. Awesome New Laser. SAFETY. Class 3b laser Due to high intensity of laser, a single pulse specularly reflected into the eye is hazardous. Requires LANL Integrated Work Document (IWD)
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New Laser Calibration Status • New Laser vs Old Laser • Safety • Pond Data • Outrigger Data • How to Combine?
SAFETY • Class 3b laser • Due to high intensity of laser, a single pulse specularly reflected into the eye is hazardous. • Requires LANL Integrated Work Document (IWD) • Safety Interlock on Plexiglass Cover • Hazard light on outside of shed • DO NOT ENTER LASER SHED, IF YOU HAVE NOT SIGNED IWD • If you want to sign IWD, you must • Take LANL Laser Safety for Class 3b & 4 • Have LANL HSR approved eye exam • Read IWD
Laser Calibration Monitor Photodiode To Front End Board & TDC Computer Controlled Optical Fiber Switch ~ 30 Fibers to Pond & ~ 30 Fibers to Outriggers Computer Controlled Optical Filter Wheel LASER Optical Fiber Prompt Pulse Computer Controlled Delay Generator To Common Stop of Time to Digital Converter
Laser Light Output Stability Pond Calibration of 1000 pulses @100 Hz x 35 filter wheel positions x 30 laser balls takes ~12 hours Each ball takes ~24 minutes Photodiode hitot varies by <5 ch in 24 minutes Still need to calibrate photodiode hitot Photodiode hitot (ch) Time (hours)
Timing Stabile of Delay Generator Timing of monitor photodiode shows no skips even for short time intervals Long term stability also < 0.5 nsec Photodiode histart (ch) Time (hours)
Lo Hi or Lo Start Hi Hi or Lo ToT Pond Calibration • 30 laser balls in pond • Central balls can calibrate ~30 top layer pmts to several 1000 pes and ~100 top layer pmts up to several 100 pes Typical Top Layer Slewing Curve
Outrigger Calibration • Laser is bright! • Combine 30 fibers entering laser shed to 3 fibers coming out of optical switch • Each of 3 fibers requires different delay due to different cable and fiber lengths • Additional optical filter is required for most outriggers • 29 outriggers need 10-3 x light sent to pond ball • 121 outriggers need 10-2 x light sent to pond ball • 19 outriggers need 10-1 x light sent to pond ball • 4 outriggers need 1 x light sent to pond ball
How to Combine? • What is relative offset between top/bottom/outriggers? • Current monitor histogram looks problematic.