He3 Target Test Items
From Hall A Wiki
Contents
Target Holding Field
- Field survey: field strengh, gradient
- Field rotation glitch check
Cell Characterization
Density
- Filling density
- Broadening of Alkali absorption
- N2 density: filling density, pressure curve
Wall Thickness
- Laser interference measurement: wall and window
Cell Volume/Geometry
- Caliper method
- Archimedes' method
Optical Pumping System
Laser Optics
- Laser power measurement
- Laser spectrum measurement/Absorption adjustment
- Calibrations of optics orientations, e.g. λ/4 plates
- Laser polarization measurement
- Optics alignment [1]
- Power consumption at laser connectors (if there is any)
Oven
- RTD calibration
- Condition optimization: oven temperature as a function of gas flow and heater power
Polarimetry
NMR
- Q-curve measurement of all pickup coils to prevent resonance
- Minimize pickup coil background with maximum RF power
- Linearity check of amplifiers: preamplifier, lock-in amplifier
- Flux calibration: pickup coil survey and flux calculation
- He3 NMRs: frequency and field sweeps (including NMRs during EPR calibration)
- AFP loss measurement
- Internal temperature measurement in pumping chamber using NMR
- NMR cross calibration: frequency vs. field, different locations
- Water NMR calibration: field sweep (frequency sweep as well if possible)
EPR
- Characterization of feedback system: proportional and integration gains
- D2 light detection optimization [2]
- EPR calibration: absolute polarization measurement
- Cross check with water calibrated NMRs
- D1 light EPR measurement (if using narrow-band laser)
MISC Studies
- Spin up time
- Relaxation time: room temperature, high temperature
- Optimization of pumping condition: laser power, oven temperature
- Polarization gradient across cell
