PAC2013 - List of Authors (Pozimski, J.K.)

Paper	Title	Page
MOPMA05	Thermal Design of the FETS Chopper Beam Dump	303
	P. Savage, M. Aslaninejad, P.A. Posocco, J.K. Pozimski Imperial College of Science and Technology, Department of Physics, London, United Kingdom A.P. Letchford, J.K. Pozimski STFC/RAL, Chilton, Didcot, Oxon, United Kingdom S. Mishra Imperial College of Science and Technology, London, United Kingdom
	Funding: M. Shruti was supported by STFC/RAL. The Front End Test Stand Project (FETS) at RAL is being built to demonstrate fast beam chopping. This is required to create precisely defined gaps in the bunched H⁻ beam which is essential in order to minimise beam losses in a synchrotron during injection. The gaps are created in the Medium Energy Beam Transport (MEBT) section of the FETS beam-line using a ‘fast-slow’ chopping scheme. This scheme uses two choppers, one fast and one slow, each kicks a portion of beam into its corresponding downstream beam dump. The challenge for the beam dump design is that it must occupy a limited longitudinal space to ensure that the beam transport is preserved and must absorb a beam power that is close to the sustainable stress limit of common engineering materials. This paper will describe the simulations made to study the cooling scheme required to absorb the power deposited in the dump plates for the fast and slow choppers.

THPSM12	A Ready-to-use Application of Laser-Plasma Accelerators using Gabor Lenses	1409
	J.K. Pozimski, M. Aslaninejad, N. Dover, Z. Najmudin, R.M. Nichols, P.A. Posocco Imperial College of Science and Technology, Department of Physics, London, United Kingdom
	Funding: R.M. Nichols was supported by EPSRC. A realistic particle distribution for a proton beam generated by laser-plasma interaction is required in order to simulate its transport through a Gabor lens system intended for use in radiobiology experiments. A stack of radiochromic films were exposed to a laser-driven proton beam of 25 MeV at the Vulcan Petawatt Experiment at Rutherford Lab and subsequently analysed to find the energy deposited per film and therefore the energy spectrum of the beam. Combined with the information on the radial profile of the dose in the films, it was possible to generate an idealised particle distribution. This distribution was sampled and used as a realistic proton source in a simulation through the Gabor lens system published at IPAC’13, scaled down to 4 MeV to fit the radiobiology experiment requirements.

Paper

Title

Page

Thermal Design of the FETS Chopper Beam Dump

303

P. Savage, M. Aslaninejad, P.A. Posocco, J.K. Pozimski
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
A.P. Letchford, J.K. Pozimski
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
S. Mishra
Imperial College of Science and Technology, London, United Kingdom

Funding: M. Shruti was supported by STFC/RAL.
The Front End Test Stand Project (FETS) at RAL is being built to demonstrate fast beam chopping. This is required to create precisely defined gaps in the bunched H⁻ beam which is essential in order to minimise beam losses in a synchrotron during injection. The gaps are created in the Medium Energy Beam Transport (MEBT) section of the FETS beam-line using a ‘fast-slow’ chopping scheme. This scheme uses two choppers, one fast and one slow, each kicks a portion of beam into its corresponding downstream beam dump. The challenge for the beam dump design is that it must occupy a limited longitudinal space to ensure that the beam transport is preserved and must absorb a beam power that is close to the sustainable stress limit of common engineering materials. This paper will describe the simulations made to study the cooling scheme required to absorb the power deposited in the dump plates for the fast and slow choppers.

THPSM12

A Ready-to-use Application of Laser-Plasma Accelerators using Gabor Lenses

1409

J.K. Pozimski, M. Aslaninejad, N. Dover, Z. Najmudin, R.M. Nichols, P.A. Posocco
Imperial College of Science and Technology, Department of Physics, London, United Kingdom

Funding: R.M. Nichols was supported by EPSRC.
A realistic particle distribution for a proton beam generated by laser-plasma interaction is required in order to simulate its transport through a Gabor lens system intended for use in radiobiology experiments. A stack of radiochromic films were exposed to a laser-driven proton beam of 25 MeV at the Vulcan Petawatt Experiment at Rutherford Lab and subsequently analysed to find the energy deposited per film and therefore the energy spectrum of the beam. Combined with the information on the radial profile of the dose in the films, it was possible to generate an idealised particle distribution. This distribution was sampled and used as a realistic proton source in a simulation through the Gabor lens system published at IPAC’13, scaled down to 4 MeV to fit the radiobiology experiment requirements.