• M. Eshraqi, M. Brandin, I. Bustinduy, C.J. Carlile, H. Hahn, M. Lindroos, C. Oyon, S. Peggs, A. Ponton, K. Rathsman
  ESS, Lund
• R. Calaga, T. Satogata
  BNL, Upton, Long Island, New York
• A. Jansson
  Fermilab, Batavia

A three year de­sign up­date for the Eu­ro­pean Spal­la­tion Source (ESS) linac is just start­ing and a full re­view of this work will be pre­sent­ed. The ac­cel­er­a­tion in the medi­um en­er­gy part of the LINAC using the spoke cav­i­ties have been op­ti­mized and the rest of the ma­chine has been re­designed to in­cor­po­rate this op­ti­miza­tion. The ESS LINAC will de­liv­er an av­er­age power of 5~MW to the tar­get in the nom­i­nal de­sign and the pos­si­bil­i­ty to up­grade to 7.5~MW has been in­clud­ed in all the de­sign steps.

Acknowledgments to all the people in the ESS LINAC Reference Group.

• 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.

• I. Bustinduy, N. Garmendia, H. Hassanzadegan, D. de Cos
  ESS Bilbao, Bilbao
• F.J. Bermejo
  Bilbao, Faculty of Science and Technology, Bilbao
• V. Etxebarria, J. Portilla
  University of the Basque Country, Faculty of Science and Technology, Bilbao
• J. Feuchtwanger
  ESS-Bilbao, Zamudio
• S. Jolly, J.K. Pozimski, P. Savage
  Imperial College of Science and Technology, Department of Physics, London
• A.P. Letchford
  STFC/RAL/ISIS, Chilton, Didcot, Oxon

The main ob­jec­tive of the Bil­bao Front End Test Stand (ETOR­FETS) is to set up a fa­cil­i­ty to demon­strate ex­per­i­men­tal­ly the de­sign ideas for the fu­ture ESS LINAC that are being pro­posed in dis­cus­sion fo­rums by the tech­ni­cal sci­en­tif­ic com­mu­ni­ty. ETOR­FETS is fo­cused on the first stage of the lin­ear ac­cel­er­a­tor, name­ly, that of the Ra­dio-Fre­quen­cy Quadrupole (RFQ) and its pre and post beam trans­port sys­tems. The RFQ bunch­es, fo­cus­es trans­verse and lon­gi­tu­di­nal­ly, and ac­cel­er­ates charged par­ti­cles in the low-en­er­gy range (up to ~ 3 MeV), thus be­com­ing one of the main com­po­nents of the ac­cel­er­at­ing struc­ture. The first RFQ sim­u­la­tions, per­formed in Su­per­fish and GPT soft­ware pack­ages, will be pre­sent­ed in this work.