LINAC2014 - List of Authors (Wheelhouse, A.E.)

Paper	Title	Page
THPP012	A Prototype 1 Mev X-Band Linac for Aviation Cargo Inspection	853
	M. Jenkins, P.K. Ambattu, G. Burt Cockcroft Institute, Lancaster University, Lancaster, United Kingdom S. Andrews, T.A. Cross, C.R. Weatherup e2v, Chelmsford, Essex, United Kingdom P.A. Corlett, P. Goudket, A.R. Goulden, P.A. McIntosh, K.J. Middleman, Y.M. Saveliev, R.J. Smith, A.E. Wheelhouse STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom S.A. Griffiths, M.D. Hancock, T. Hartnett, C. Hill, J.P. Hindley, B.G. Martlew, N. Templeton STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
	Aviation cargo Unit Load Device (ULD) containers are typically much smaller than standard shipping containers, with a volume of around 1m3. Standard 3-6 MeV X-ray screening linacs have too much energy to obtain sufficient contrast when inspecting ULD’s, hence a lower 1 MeV linac is required. In order to obtain a small physical footprint, which can be adapted to mobile platform applications a compact design is required, hence X-band technology is the ideal solution. A prototype 1 MeV linac cavity has been designed by Lancaster University, manufactured by Comeb (Italy) and tested at STFC Daresbury Laboratory using an e2v magnetron, modulator and electron gun. The cavity is a bi-periodic π/2 structure, with beam-pipe aperture coupling to simplify the manufacture at the expense of shunt impedance. The design, manufacture and testing of this linac structure is presented.

THPP126	Design of the High Repetition Rate Photocathode Gun for the CLARA Project	1155
	B.L. Militsyn, L.S. Cowie, P. Goudket, J.W. McKenzie, A.E. Wheelhouse STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom G. Burt Cockcroft Institute, Lancaster University, Lancaster, United Kingdom T.J. Jones STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom V.V. Paramonov, A.K. Skasyrskaya RAS/INR, Moscow, Russia
	The CLARA injector is required to deliver ultrashort singe electron pulses with a charge of 250 pC following with a repetition rate of 100 and/or 400 Hz. It should also provide 2 us trains of twenty 25 pC pulses with a repetition rate 100 Hz. To meet this challenge, a 1.5 cell S-band photocathode gun with a field of up to 120 MV/m and coaxial coupling has been chosen. The length of the first cell of 0.5 is decided on the basis of beam dynamic simulation with the goal to obtain optimal for CLARA parameters. In order to improve amplitude and phase stability of the RF field, the gun is equipped with RF probes, which will provide feedback to the RF system. The gun and coupler were designed to accept up to 10 MW peak and 10 kW average RF powers. Cooling will be achieved by water channels cut into the bulk of the copper. The coupler will transition from waveguide to coax using an innovative H-shaped dual feed system that cancels out any dipole mode components and allows tuning of the match. The RF and mechanical design of the CLARA high brightness photocathode gun along with beam dynamics simulations are presented in this paper.

Paper

Title

Page

A Prototype 1 Mev X-Band Linac for Aviation Cargo Inspection

853

M. Jenkins, P.K. Ambattu, G. Burt
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
S. Andrews, T.A. Cross, C.R. Weatherup
e2v, Chelmsford, Essex, United Kingdom
P.A. Corlett, P. Goudket, A.R. Goulden, P.A. McIntosh, K.J. Middleman, Y.M. Saveliev, R.J. Smith, A.E. Wheelhouse
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
S.A. Griffiths, M.D. Hancock, T. Hartnett, C. Hill, J.P. Hindley, B.G. Martlew, N. Templeton
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom

Aviation cargo Unit Load Device (ULD) containers are typically much smaller than standard shipping containers, with a volume of around 1m3. Standard 3-6 MeV X-ray screening linacs have too much energy to obtain sufficient contrast when inspecting ULD’s, hence a lower 1 MeV linac is required. In order to obtain a small physical footprint, which can be adapted to mobile platform applications a compact design is required, hence X-band technology is the ideal solution. A prototype 1 MeV linac cavity has been designed by Lancaster University, manufactured by Comeb (Italy) and tested at STFC Daresbury Laboratory using an e2v magnetron, modulator and electron gun. The cavity is a bi-periodic π/2 structure, with beam-pipe aperture coupling to simplify the manufacture at the expense of shunt impedance. The design, manufacture and testing of this linac structure is presented.

THPP126

Design of the High Repetition Rate Photocathode Gun for the CLARA Project

1155

B.L. Militsyn, L.S. Cowie, P. Goudket, J.W. McKenzie, A.E. Wheelhouse
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
G. Burt
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
T.J. Jones
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
V.V. Paramonov, A.K. Skasyrskaya
RAS/INR, Moscow, Russia

The CLARA injector is required to deliver ultrashort singe electron pulses with a charge of 250 pC following with a repetition rate of 100 and/or 400 Hz. It should also provide 2 us trains of twenty 25 pC pulses with a repetition rate 100 Hz. To meet this challenge, a 1.5 cell S-band photocathode gun with a field of up to 120 MV/m and coaxial coupling has been chosen. The length of the first cell of 0.5 is decided on the basis of beam dynamic simulation with the goal to obtain optimal for CLARA parameters. In order to improve amplitude and phase stability of the RF field, the gun is equipped with RF probes, which will provide feedback to the RF system. The gun and coupler were designed to accept up to 10 MW peak and 10 kW average RF powers. Cooling will be achieved by water channels cut into the bulk of the copper. The coupler will transition from waveguide to coax using an innovative H-shaped dual feed system that cancels out any dipole mode components and allows tuning of the match. The RF and mechanical design of the CLARA high brightness photocathode gun along with beam dynamics simulations are presented in this paper.