• J.J. Back
  University of Warwick, Coventry
• J. Alonso
  Fundación Tekniker, Elbr (Guipuzkoa)
• F.J. Bermejo
  Bilbao, Faculty of Science and Technology, Bilbao
• R. Enparantza
  Fundación TEKNIKER, Eibar (Gipuzkoa)
• D.C. Faircloth, A.P. Letchford
  STFC/RAL, Chilton, Didcot, Oxon
• C. Gabor
  STFC/RAL/ASTeC, Chilton, Didcot, Oxon
• S.R. Lawrie
  STFC/RAL/ISIS, Chilton, Didcot, Oxon
• J. Lucas
  Elytt Energy, Madrid
• J.K. Pozimski, P. Savage
  Imperial College of Science and Technology, Department of Physics, London

The Front End Test Stand (FETS) at the Rutherford Appleton Laboratory is intended to demonstrate the early stages of acceleration (0-3 MeV) and beam chopping required for high power proton accelerators, including proton drivers for pulsed neutron spallation sources and neutrino factories. A Low Energy Beam Transport (LEBT), consisting of three solenoids and four drift sections, is used to transport the H^- beam from the ion source to the FETS Radio Frequency Quadrupole. We present the status of the installation and commissioning of the LEBT, and compare particle dynamics simulations with preliminary measurements of the H^- beam transport through the LEBT.

• A.P. Letchford, M.A. Clarke-Gayther, D.C. Faircloth, S.R. Lawrie, M. Perkins, P. Wise
  STFC/RAL/ISIS, Chilton, Didcot, Oxon
• S.M.H. Alsari, S. Jolly, D.A. Lee, P. Savage
  Imperial College of Science and Technology, Department of Physics, London
• I. Ariz, R. Enparantza, P. Romano, A. Sedano
  Fundación TEKNIKER, Eibar (Gipuzkoa)
• J.J. Back
  University of Warwick, Coventry
• F.J. Bermejo
  Bilbao, Faculty of Science and Technology, Bilbao
• M. Eguiraun
  ESS-Bilbao, Zamudio
• V. Etxebarria
  University of the Basque Country, Faculty of Science and Technology, Bilbao
• C. Gabor, D.C. Plostinar
  STFC/RAL/ASTeC, Chilton, Didcot, Oxon
• N. Garmendia, H. Hassanzadegan
  ESS Bilbao, Bilbao
• A. Kurup
  Fermilab, Batavia
• J.K. Pozimski
  STFC/RAL, Chilton, Didcot, Oxon

The Front End Test Stand (FETS) under construction at the Rutherford Appleton Laboratory is the UK's contribution to research into the next generation of High Power Proton Accelerators (HPPAs). HPPAs are an essential part of any future Spallation Neutron Source, Neutrino Factory, Muon Collider, Accelerator Driven Sub-critical System, Waste Transmuter etc. FETS will demonstrate a high quality, high intensity, chopped H-minus beam and is a collaboration between RAL, Imperial College and the Universtity of Warwick in the UK and the Universidad del Pais Vasco in Spain. This paper describes the current status and future plans of FETS.

• S.R. Lawrie, D.C. Faircloth, A.P. Letchford, M. Perkins
  STFC/RAL/ISIS, Chilton, Didcot, Oxon
• C. Gabor
  STFC/RAL/ASTeC, Chilton, Didcot, Oxon
• J.K. Pozimski
  Imperial College of Science and Technology, Department of Physics, London

The front end test stand (FETS) [1] is entering the next stage of construction and commissioning, with the three-solenoid magnetic low energy beam transport (LEBT) line being installed. A thorough characterization of the beam leaving the Penning H^- ion source has been performed. This includes measurements of the beam current using toroids and of the transverse emittance using slit-slit scanners. These measurements are performed over a wide range of source discharge and extraction parameters in order to understand how the transmission may be improved. Comments on the quality of the beam to be injected into the FETS radio frequency quadrupole (RFQ) are given.

• R. Enparantza, I. Ariz, P. Romano, A. Sedano
  Fundación TEKNIKER, Eibar (Gipuzkoa)
• F.J. Bermejo
  Bilbao, Faculty of Science and Technology, Bilbao
• D.C. Faircloth, A.P. Letchford
  STFC/RAL/ISIS, Chilton, Didcot, Oxon

A Front End Test Stand is being built at the Rutherford Appleton Laboratory in the UK to demonstrate a chopped H− beam of sufficiently high beam quality for future high-power proton accelerators (HPPA). The test stand consists on a negative Hydrogen ion source, a solenoid LEBT, a 324 MHz four vane RFQ, a MEBT composed of rebunching cavities and choppers and a set of diagnostics ending with a beam stop. The beam stop, which has to accept a 3 MeV, 60 mA, 2 ms, 50 Hz (10% duty factor) H− beam, consists of a coaxial double cone configuration where the inner cone's inner surface is hit by the beam and the inter-cone gap is cooled by high-speed water. The cones are situated inside a water tank and mounted at one end only to allow thermal expansion. In order to minimize both prompt and induced radiation pure aluminium is used, but the poor mechanical properties of pure aluminium are overcome by employing a metal spinning process that increases the yield strength to several times the original value of the non-deformed material. CFD and FEM codes have been used to avoid high temperature gradients, to minimize thermal stresses, and to minimize fatigue caused by the pulsed beam.

• I. Bustinduy, D. Fernandez-Cañoto, D. de Cos
  ESS Bilbao, Bilbao
• J. Alonso, M. Eguiraun, R. Enparantza, M. Larrañaga
  Fundación TEKNIKER, Eibar (Gipuzkoa)
• F.J. Bermejo
  Bilbao, Faculty of Science and Technology, Bilbao
• V. Etxebarria, J. Jugo, J. Portilla
  University of the Basque Country, Faculty of Science and Technology, Bilbao
• D.C. Faircloth, S.R. Lawrie, A.P. Letchford
  STFC/RAL/ISIS, Chilton, Didcot, Oxon
• J. Feuchtwanger
  ESS-Bilbao, Zamudio
• S. Jolly
  Imperial College of Science and Technology, Department of Physics, London
• J. Lucas
  Elytt Energy, Madrid

The rationale behind the Bilbao Accelerator Ion Source Test Stand (ITUR) project is to perform a comparison between different kinds of hydrogen ion sources using the same beam diagnostics setup. In particular, a direct comparison will be made in terms of the emittance characteristics of Penning-type sources such as those currently being used in ISIS (UK) and those of microwave type such as CEA-Saclay and INFN. The aim here pursued is to build an Ion Source Test Stand where virtually any type of source can be tested and, thus, compared to the results of other sources under the same gauge. It would then be possible to establish a common ground for effectively comparing different ion sources. The work here presented reports on the first simulations for the H-/H⁺ extraction system, as well the devices that conform the diagnostic vessel: Faraday Cup, Pepperpot and Retarding Potential Analyzer (RPA), among others.

• D.C. Faircloth, S.R. Lawrie, A.P. Letchford, M. Perkins
  STFC/RAL/ISIS, Chilton, Didcot, Oxon

The Front End Test Stand (FETS) under construction at the Rutherford Appleton Laboratory is the UK's contribution to research into the next generation of High Power Proton Accelerators (HPPAs). Running at duty cycles of up 50 Hz with pulse lengths of 2 ms are required. This paper presents initial Hminus beam currents and emittance measurements for long pulse lengths.