Author: Plawski, T. E.
Paper Title Page
MOPMY002 Simulation and Experimental Studies of a 2.45GHz Magnetron Source for an SRF Cavity with Field Amplitude and Phase Controls 514
  • H. Wang, T. E. Plawski, R.A. Rimmer
    JLab, Newport News, Virginia, USA
  • A. Dudas, M.L. Neubauer
    Muons, Inc, Illinois, USA
  Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177 and NP STTR Grant DE-SC0013203.
Phase lock to an SRF cavity by using injection signal through output waveguide of a magnetron has been demonstrated [1, 3]. Amplitude control using magnetic field trimming and anode voltage modulation has been studied using MATLAB/Simulink simulations [2]. Based on these, we are planning to use an FPGA based digital LLRF system, which allows applying various types of control algorithms in order to achieve the required accelerating field stability. Since the 1497 MHz magnetron is still in the design stage, the proof of principle measurements of a commercial 2450 MHz magnetron are carried out to characterize the anode I-V curve, output power (the tube electronic efficiency), frequency dependence on the anode current (frequency pushing) and the Rieke diagram (frequency pulling by the reactive load). Based on early Simulink simulation, experimental data and extension of the Adler equation governing injection phase stability by Chen's model, the specification of the new LLRF control chassis for both 2450 and 1497MHz systems are presented in this paper.
DOI • reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPMY002  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
THPOY060 Four Beam Generation for Simultaneous Four-Hall Operation at CEBAF 4240
  • R. Kazimi, J.M. Grames, J. Hansknecht, A.S. Hofler, G.E. Lahti, T. E. Plawski, M. Poelker, R. Suleiman, Y.W. Wang
    JLab, Newport News, Virginia, USA
  Funding: Authored by JSA, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Gov't retains a non-exclusive, paidup, irrevocable, worldwide license to publish or reproduce this for U.S. Gov't purposes.
As part of the CEBAF 12 GeV upgrade at Jefferson Lab, a new experimental hall was added to the existing three halls. To deliver beam to all four halls simultaneous-ly, a new timing pattern for electron bunches is needed at the injector. This pattern change has consequences for the frequency of the lasers at the photogun, beam behavior in the chopping system, beam optics due to space charge, and setup procedures. We have successfully demonstrated this new pattern using the three existing drive lasers. The implementation of the full system will occur when the fourth laser is added and upgrades to the Low Level RF (LLRF) are complete. In this paper we explain the new bunch pattern, the challenges for setting and measuring the pattern such as 180° RF phase ambiguity, addition of the fourth laser to the laser table and LLRF upgrade.
DOI • reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPOY060  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)