July 31, 2017 to August 4, 2017
Fermi National Accelerator Laboratory
US/Central timezone

Beam Based RF Voltage Measurements at the Fermilab Booster (RCS) for Intensity Upgrade

Aug 3, 2017, 2:45 PM
West Wing (Fermi National Accelerator Laboratory)

West Wing

Fermi National Accelerator Laboratory

Presentation Accelerators Accelerators


Dr Chandra Bhat (Fermilab)


Fermilab Booster is the second oldest rapid cycling synchrotron (RCS) in the world. In the intensity frontier (IF) program of Fermilab, the Booster plays a critical role. Currently, (PIP-era) the Booster receives proton beam from the 400 MeV normal conducting LINAC and accelerates the beam to 8 GeV using its twenty RF stations that are distributed around the ring. The main dipole magnets of the Booster cycle at 15 Hz and follow a sinusoidal magnetic ramp. During the PIP-II era, this cycle rate will be increased to 20 Hz and a higher intensity beam (>1.5 times higher than the PIP intensity) will be injected from a superconducting LINAC. The required accelerating RF voltage during PIP-II era will need to be about 30% more than during the PIP era. Therefore, it is extremely important to find out the current RF voltage by carrying out beam-based measurements to specify the needed upgrades to the Booster RF system. During the beam cycle the magnetic field is changing all the time. Due to this, 1) measuring/calibrating the RF voltage used for beam capture and acceleration, 2) longitudinal beam tomography, are not trivial tasks. Here we present a method to accomplish both tasks near injection and extraction energies of the Booster. Python/Matlab programs* have been developed which use wall current monitor data to measure synchrotron frequencies and extract the RF voltage with an accuracy of 13% at injection and 7% at extraction. We have also attempted to obtain the beam tomography in the longitudinal phase space using these data. The method developed here is applicable to any similar RCSs in the world. *The author would like to thank Shreyas Bhat from the Fermilab Computing Division for his involvement in developing a necessary Python program for the data analyses. Work supported by Fermi Research Alliance, LLC under Contract No. De-AC02 07CH11359 with the United States Department of Energy

Primary author

Dr Chandra Bhat (Fermilab)

Presentation materials