Research Notes and Documents

Tech Notes

WF Calibration -- 5/4/18 Calibration of the UITF Wien Filter (WF) by adjusting the E-Field and B-Field to determine the velocity of the electron beam
Spring 2018 QE vs. Charge & Fall 2016 QE vs. Charge -- 5/24/18 Plots of QE vs. Charge data from the CEBAF injector. The Spring 2018 plot corresponds to when the vertical WF was at 50 degrees and the horizontal WF was off. The Fall 2016 plot is the opposite with the horizontal WF at 50 degrees and the vertical WF was off.
Magnetic field in front of photogun idea -- 5/25/18 An idea that I had that may solve the problem of ion back-bombardment due to ion creation downstream of the anode.
Derivation of QE Formula -- 6/1/18 Derivation of the formula for photocathode QE based on electron current, laser power, and wavelength

QE vs. Charge -- Plot of QE vs Charge between 10:13:00 and 15:12:00 on 7/11/18
Pickoff vs Inline -- Plot of pickoff power (to the photocathode) vs. inline power (before power meter) to determine power correction factor

Voltage vs. Distance Line Plot -- 6/27/18 A line graph of voltage vs. distance using data from Gabriel
Voltage vs. Distance 3D Plot -- 6/27/18 An extension of the graph above into 3D space. Apparently, the potential is symmetric about the z-axis...?

RGA Spectrum After 2 Days -- RGA Spectrum for gun chamber taken on 5/21/18 after prepping for 2 days, analyzed using gnuplot on 6/11/18. Each peak was fit using a gaussian function in order to determine the maximum and standard deviation of each peak.
Ionization Cross Sections V1 -- 6/14/18, Updated on 6/15/18, Analysis of the RGA Spectrum "After 2 Days" (see below), a sample calculation for the ionization cross section of hydrogen gas, and a plot of ionization cross section vs. beam energy (electron kinetic energy).
Ionization Cross Sections V2 -- 6/19/18 Updated document above to include section on numerical calculation of ionization rates.
Ionization Cross Sections V3 -- 6/22/18 Updated document above to include tables of calculated values for the ion production rates of the gas species using normalized partial pressures.
Ion Production Rate vs. Beam Energy -- 6/25/18 Formula derivation and plot of the ionization rate of gas species found in the "After 2 Days" RGA spectrum as a function of beam energy (gun voltage).