The experimental method involved altering the trajectory of the beam through either CC1 or CC2 using horizontal or vertical corrector dipoles located upstream of the cavity. The data consists of bunch-by-bunch BPM data and/or streak camera image data collected by MATLAB scripts over many beam pulses. In addition to the BPM data, HOM and cavity gradient waveforms are collected along with magnet settings. The BPM, HOM, cavity, and magnet data is written to a matlab file for later processing. The streak camera image data is saved to PNG image files.
Results¶The raw data is stored in the Files section above.
- MATLAB Data -- This data is stored in .mat files beginning with AllData_ and suffixed with a timestamp. They contain the BPM, HOM, cavity gradient, and corrector magnet data. The precise contents of the files are detailed in Description of Contents of AllData_*.mat Files.
- Streak Camera Image Data -- This data is in PNG format and is stored in .zip files beginning with StreakCamera_. They are time stamped with the day they were collected.
- ACNET Logger Data -- This data is stored in .mat files beginning with LoggerData_ and suffixed with a timestamp. These files contain the ACNET logged data of all correctors and quadrupoles, the solenoids, and the gun, CC1, CC2 set point amplitudes and phases. The cavity phases are arbitrary. The .mat file has a single structure variable called
devList, with a field for each ACNET device. Each device field is a struct with .time and .value fields, i.e.
- November 08 - November 30, 2017 Long-range transverse and longitudinal wakefield effects using downstream BPM data in collaboration with LANL.
- March 01 - April 03, 2019 Short-range transverse wakefield effects using downstream streak camera imaging.
- December 17 - December 19, 2019 Long-range transverse wakefield effects using downstream BPM data in collaboration with SLAC. Also included quadrupole HOM modes as well as previously-studied dipole HOM modes.
- February 24 - February 27, 2020 Long- and short-range transverse wakefield effects using downstream BPMs and streak camera imaging. Also in collaboration with SLAC.
- Lumpkin et al., Submacropulse Electron-Beam Dynamics Correlated with Higher-Order Modes in TESLA-type Superconducting RF Cavities, Phys. Rev. Accel. Beams 21, 064401 (2018)