07 Aug 2007 C1C Adam Stooke USAF Academy Physics Department SIST Outbrief Supervisor: Yuriy Pischalnikov, Technical Division

Resonance Control: Pre-Load & A Case Study in Measurement

Outline Superconducting Radio Frequency (SCRF) Cavities Resonance & Tuning Measuring the Preload Current Configuration New Hardware Profile Recommended Improvements

Superconducting RF Cavity

Operational Hurdle: Cost Energy/Power Consumption Land, Materials, Production Precision

Energy Savings SC RF Cavities Electromagnetic Resonance Narrow-band Power Supply 1.3 GHz f 1/2 f 1/2 ≈ 200 Hz 1 µm  400 Hz

Detuning Microphonics Lorentz Force

Pulse Mode

Lorentz Force Detuning 35 MV/m  500 ~ 600 Hz

Tuning

Pre-Load

Data Analysis Tension! Fickle Calibration

Measurement Equipment

Measurement Sensitivities SS 316 E = 193 GPa 50 lbs  11.5 µε  8 mΩ

Temperature Calibration, 5 K, 80 mK  8 mΩ

RTD 5 K, 80 mK  4 Ω

Performance Profile Range Resolution Current 100  ……10 μ  mA 1 k  μ  mA 10 k  ……...1 m  μA 100 k  …….10 m  μA 1 M  m  μA 10 M   μA Resolution Noise Reduction Mode Aperture Time LabVIEW 8.2 NI-DMM 2.7 (PXI 4071) NI-SWITCH 3.3 (PXI 2501) Vishay Resistor 350 Ω (0.005%) 4-wire measurement

Performance Profile SETTINGSRESULTS Range: 1 k  Resolution: 7 ½µ = Range = Noise- rej: high-orderApt. time: 6σ = Time = 5.2 Range: 10 k  Resolution: 7 ½µ = Range = Noise- rej: high-orderApt. time: 6σ = Time = 5.4 Range: 1 k  Resolution: 7 ½µ = Range = Noise- rej: second-orderApt. time: 2σ = Time = 1.9 Range: 10 k  Resolution: 7 ½µ = Range = 0.11 Noise- rej: second-orderApt. time: 2σ = 0.030Time = 2.1 Range: 1 k  Resolution: 7 ½µ = Range = Noise- rej: normalApt. time: 1σ = Time = 1.1 Range: 10 k  Resolution: 7 ½µ = Range = Noise- rej: normalApt. time: 1σ = Time = 1.3 *Time is seconds for switching and reading 50 point multipoint*Each set of statistics covers 5,000 measurements SG: 8 mΩ

Performance Profile *Time is seconds for switching and reading 50 point multipoint*Each set of statistics covers 5,000 measurements SETTINGSRESULTS Range: 100 k  Resolution: 7 ½µ = Range = Noise- rej: high-orderApt. time: 6σ = 0.20Time = 6.4 Range: 1 M  Resolution: 7 ½µ = Range = 3.81 Noise- rej: high-orderApt. time: 6σ = 0.68Time = 10.2 Range: 100 k  Resolution: 7 ½µ = Range = Noise- rej: second-orderApt. time: 2σ = 0.038Time = 3.1 Range: 1 M  Resolution: 7 ½µ = 319.4Range = Noise- rej: second-orderApt. time: 2σ = 1.0Time = 6.9 Range: 100 k  Resolution: 7 ½µ = Range = Noise- rej: normalApt. time: 1σ = 0.038Time = 2.3 Range: 1 M  Resolution: 7 ½µ = 320.6Range = Noise- rej: normalApt. time: 1σ = 2.1Time = 6.0 RTD: 4 Ω 1 µA

Performance Profile *Time is seconds for switch connect and 20 point multipoint read *Each set of statistics covers 200 measurements. SETTINGSRESULTS Resolution: 5 ½ Noise- rej: high-order µ = σ = 7.1 Range = Time = 5.08 Resolution: 6 ½ Noise- rej: high-order µ = σ = 0.82 Range = Time = 9.9 Resolution: 7 ½ Noise- rej: high-order µ = σ = 0.36 Range = Time = 32 Resolution: 5 ½ Noise- rej: second-order µ = σ = 7.6 Range = Time = 5.2 Resolution: 6 ½ Noise- rej: second-order µ = σ = 0.86 Range = 4.93 Time = 9.9 Resolution: 7 ½ Noise- rej: second-order µ = σ = 0.34 Range = Time = 32 Resolution: 5 ½ Noise- rej: normal µ = 348 σ = 13 Range = Time = 5.2 Resolution: 6 ½ Noise- rej: normal µ = σ = 0.76 Range = Time = 9.9 Resolution: 7 ½ Noise- rej: normal µ = σ = 0.36 Range = Time = 32 *Range is 10 MΩ for all. RTD: 4 Ω 1 µA

Sensor Improvements Reliability Accuracy How? Decrease demands

Bullet Modification Material SS 316: E = 193 GPa Al 2014-T4: E = 70 GPa Nearly 3 times the strain Size 10 x 10 x 10 mm 7.5 x 7.5 x 10 mm Nearly 2 times the stress Industry standard for measurements: µε 50 lbs: 8 mΩ  40 mΩ 80 mK  400 mK Improve from 115 µε to ~600 µε

Bullet Modification RequirementMaterial Property Maximum Compressive Force: 10,000 N Maximum Compressive Stress: 178 MPa Compressive Strength: 425 MPa Shear Force: 450 N Shear Stress: 64 MPa Shear Strength: 262 MPa Spring constant >> 9 N/µm (Latest setting of CuBe 2 disc springs in HTS) Spring constant: 394 N/µm (1.93 kN/µm for SS 316, 1 cm 3 ) *Bullet material requirements and properties for a 7.5 x 7.5 x 10 mm bullet of aluminum 2014-T4

Gauge Modification Placement of Temperature Sensors

Gauge Modification Gauge Selection 4 K  Karma-alloy S-T-C number

Gauge Modification Gauge Configuration Wheatstone Bridge Full Poisson Bridge

Gauge Modification Gauge Configuration Wheatstone Bridge Half Bridge (Bending)

Conclusion Cavity Resonance Control Piezostack Preload Bullet & Strain Gauge Temperature Compensation New: Bullet SG Configuration Control & Measurement Hardware

Questions? C1C Adam Stooke USAF Academy Physics Department Supervisor: Yuriy Pischalnikov Technical Division