1. Jarred Alexander Young December 10, 2012

2.  Filament power supply has been repaired and returned  Beam Testing can continue  Research methods of incorporating data filtering with measurements through Keithley instruments  Looked into LabView commands and programming structure for Keithley instruments

3.  Used to measure the energy distribution of particle beams  Consists of:  Ground grid-allows beam to bias grid to beam bias  Retarding grid- sweeps multiple potentials to repel lower energy particles while higher- energy particles pass freely  Supression grid- prevents oppositely-charged particles from affecting data Fig.1: RPA Conceptual Diagram [1]

4.  Beam focused through energy analyzing grid aperture current measured by encased collector  Retarding sweep provided by KE2410 Sourcemeter  Current measurements provided by KE6485 picoammeter  Beam sweep conducted remotely through LabView  FC-71-A includes:  Floating/ground grid, “G”  Retarding Grid, “R”  Supression grid for secondary electrons, “S”  Faraday cup for current collection Fig. 2: FC-71-A Layout [2]

5.  Both Keithley devices contain internal data filtering schemes  Moving- allows for readings to be averaged over a period of time and only takes to account the most recent readings until the procedure is completed  Repeating- allows reading from one source level to be averaged after a certain number of points to produce one reading and does not average data from other levels ▪ Useful for source sweeps  Filtering must be activated prior to sweep to smooth data

6.  Learning LabView commands for Keithley instruments through example files  Commands in current program provide little documentation  Example programs do not use all the commands available  Context help (as pictured on right) indicates each terminal’s function, but not options and their significance  More documentation in user’s manuals for instruments, but not completely relatable to LabView

7.  Consulted with National Instruments on documentation issues  Talked about upgrading to commands that are NI- supported  Right-clicking on new commands terminals should allow for access to constants  Discovered this works with older commands as well

8.  Keithley drivers come with “VI Tree” which shows the user the general programming path in LabView for their instruments  Can use this to figure out how to edit current programs with filter commands

9.  Re-integrate and test filament power supply  Augment LabView programs to allow for both filtering of Picoammeter results and Sourcemeter results  Perform beam testing while measuring current levels of all power supplies  Compile test matrix of energy levels