• B. Jones, D.J. Adams, S.J.S. Jago, H. V. Smith, C.M. Warsop
  STFC/RAL/ISIS, Chilton, Didcot, Oxon

The ISIS Fa­cil­i­ty at the Ruther­ford Ap­ple­ton Lab­o­ra­to­ry in the UK pro­duces in­tense neu­tron and muon beams for con­densed mat­ter re­search. The ac­cel­er­a­tor fa­cil­i­ty con­sists of a 70 MeV H^- linac and a 50 Hz pro­ton syn­chrotron ac­cel­er­at­ing up to 3.75x10¹³ pro­tons per pulse from 70 to 800 MeV, de­liv­er­ing a mean beam power of 0.24 MW. Pre­sent up­grade stud­ies are in­ves­ti­gat­ing how re­place­ment of the ex­ist­ing linac and in­creased in­jec­tion en­er­gy could in­crease beam power in the ex­ist­ing ISIS ring. Such an up­grade would re­place one of the old­est sec­tions of the ISIS ma­chine, and with re­duced space charge and op­ti­mised in­jec­tion, may allow sub­stan­tial­ly in­creased in­ten­si­ty in the ring, per­haps to­wards the 0.5 MW regime. A crit­i­cal as­pect of such an up­grade would be the new high­er en­er­gy in­jec­tion straight. This paper sum­maris­es beam dy­nam­ics and hard­ware re­quire­ments for 180MeV H^- charge ex­change in­jec­tion into ISIS in­clud­ing; op­ti­mi­sa­tion of the in­jec­tion mag­nets; re­quire­ments for beam dumps and re­sults of strip­ping foil sim­u­la­tions with es­ti­mates of strip­ping ef­fi­cien­cy and foil heat­ing.

• J.W.G. Thomason, D.J. Adams, D.J.S. Findlay, I.S.K. Gardner, S.J.S. Jago, B. Jones, A.P. Letchford, R.J. Mathieson, S.J. Payne, B.G. Pine, A. Seville, H. V. Smith, C.M. Warsop, R.E. Williamson
  STFC/RAL/ISIS, Chilton, Didcot, Oxon
• J. Pasternak
  STFC/RAL, Chilton, Didcot, Oxon
• C.R. Prior, G.H. Rees
  STFC/RAL/ASTeC, Chilton, Didcot, Oxon

The ISIS Fa­cil­i­ty based at the Ruther­ford Ap­ple­ton Lab­o­ra­to­ry in the UK is the world's most pro­duc­tive spal­la­tion neu­tron source. Present­ly it runs at beam pow­ers of 0.2 MW, with RF up­grades in place to sup­ply in­creased pow­ers for the new Sec­ond Tar­get Sta­tion. In­creas­ing in­jec­tion en­er­gy into the syn­chrotron be­yond the ex­ist­ing 70 MeV level has sig­nif­i­cant po­ten­tial to in­crease in­ten­si­ty as a re­sult of re­duced space charge. This paper out­lines stud­ies for this up­grade op­tion, which in­clude mag­net and power sup­ply up­grades to achieve a prac­ti­cal in­jec­tion sys­tem, man­age­ment of in­creased in­jec­tion re­gion ac­ti­va­tion lev­els due to high­er en­er­gy un-stripped par­ti­cles and en­sur­ing the mod­i­fied lon­gi­tu­di­nal and trans­verse beam dy­nam­ics dur­ing in­jec­tion and ac­cel­er­a­tion are pos­si­ble with low loss at high­er in­ten­si­ty lev­els.