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ISOLDE scientific coordinator’s report ISCC meeting, February 4, 2010 A. Herlert, CERN PH-SME-IS Running statistics 2009 Status of experiments HV platform renovation Status ISOLDE web page ISOLDE schedule 2009 (Apr 20 - Nov 23) Requested shifts: • 662 in total • 96 different beams • 627 for 51 experiments Scheduled shifts (~70%): • 463 in total • 62 different beams • 437 for 39 experiments REX-ISOLDE: • 273 shifts requested • 140 shifts scheduled • 9 experiments (8 runs) • additional WITCH runs (need REXTRAP) GPS A. Herlert HRS ISCC February 4, 2010 ISOLDE beam time summary 2009 • ISOLDE delivered 350 RIB shifts • • 288 (82.3%) for INTC experiments 62 (17.7%) other • Standard target check + TISD + REX-MD • Coordinators reserve: debugging, recovery, tests, LOIs • • • A. Herlert 40 research projects (IS experiments) – 6 with no beam 2 LOIs Integrated # protons • 6.65E+19 • Running for 223 days • More requests for GPS ISCC February 4, 2010 RIB overview GPS/HRS 2009 PSB septum leak (no target change) and PISOMOVE problem on/off-time from radiation monitors Power cut and severe vacuum problems LINAC2 vacuum problem HRS frontend blocked 52% of possible RIB shifts used (1.57 shifts/day) (55% in 2006 61% in 2007 56% in 2008) 223 days of on-line operation A. Herlert ISCC February 4, 2010 ISOLDE shift distribution 2009 A. Herlert ISCC February 4, 2010 ISOLDE shift distribution 2000-2009 A. Herlert ISCC February 4, 2010 Number of shifts Shift distribution 1998-2009 A. Herlert ISCC February 4, 2010 Key resources: targets 2009 • Actinide targets • 218 shifts (out of 350) [62%] • 12 new units + 2 old (one not used) • In total 27 targets • 23 new units • 2 not used A. Herlert ISCC February 4, 2010 Key resources: RILIS 2009 • 155.5 total RIB shifts • 152 shifts for INTC experiments • ~2000 hours for online work • includes setup, yield checks, etc. • >2100 hours total running time (incl. off-line tests) • 20 IS experiments (13 runs) • Beams: Mn, Be, Ga, Ag, Nd, Po, Mg, Sn, Zn, Ni (all with Nd:YAG) A. Herlert ISCC February 4, 2010 REX-ISOLDE 2002-2009 • 91 RIB shifts delivered to experiments • + 5 RIB shifts for development A. Herlert ISCC February 4, 2010 New and closed experiments at ISOLDE Update November 2009 meeting • 76 shifts out of 146 approved • 4 new experiments IS495 - IS498 ISOLDE experiments to be closed • IS410, IS420, IS438, IS461, and IS470 A. Herlert ISCC February 4, 2010 Accelerator schedule 2010 (V1.3) ISOLDE dates: protons from PSB April 26 physics start ISOLDE April 29 protons stop November 22 (i.e. 29.5 weeks for physics as compared with 31 weeks in 2009) Longer shutdown period due to new HRS front-end and new vacuum system Several long periods of MD partly with parasitic beam to ISOLDE (not guaranteed) A. Herlert ISCC February 4, 2010 Follow up: floor space for experiments MISTRAL MINIBALL ISOLTRAP Em Ch WITCH A. Herlert b ISCC February 4, 2010 Status of experiments - MISTRAL • Clean-up ongoing • RFQ buncher and cooler of MISTRAL removed (shipped to University Mainz) • Removal of 22t magnet planned in March 2010 (opening to hall extension needs to be enlarged by 50cm – work to be done in February 2010) Oct 2009 A. Herlert ISCC February 4, 2010 Status of experiments - ASPIC • ISOLDE group owner of equipment • LOI submitted and will be discussed at February 2010 INTC meeting A. Herlert ISCC February 4, 2010 Status of experiments - HV Platform • Can only be used for collections Nov 2009 • Acceleration stage not functional • Need new transformer? • Check vacuum system Renovation of HV platform needed Information collected by Karl Johnston A. Herlert ISCC February 4, 2010 HV Platform – present location Located in the middle of the hall, between CRIS and ISOLTRAP A. Herlert ISCC February 4, 2010 Collection chamber Status • Platform consists of a (no-longer used) cryostat and a small collection chamber • Components on the platform are powered via an external motor when whole system is under high voltage • However, present setup not very user-friendly (vacuum, general operation) - beam optics a problem • Occupying large floor space, relative to use • Safety report from 2009 not very positive Cryostat A. Herlert External motor ISCC February 4, 2010 Some history • The present platform was designed and constructed for a specific experiment (IS303). • Originally mounted in ISOLDE-3 • Due to budget restrictions most of the components of the existing installation were taken from equipment available at CERN. • Only the driving motor for the power generator was obtained commercially. Quoted performance parameters High Voltage: Design aim: 400 kV Tube limitation: 500 kV HV Generator: 300 kV Resistor chain: 260 kV Practical limit: 220 kV 3-Phase Power Generator: 7 kW Optical links used: GPIB, ETHERNET, TTL pulses Since 2007, HV power supply has been broken Only collection point has been used (sparingly) A. Herlert ISCC February 4, 2010 Is there a need for a post-accelerated (non-REX) beam? YES: High Voltage platform for TISD • (HIE)-ISOLDE offers the largest choice of ISOL beams; it should further be extended. • TISD can offer higher intensities for many exotic beams. • The High Voltage platform (up to 260kV) is used to deduce release properties of new targets with implanted long-lived radiotracers and offline gamma spectroscopy. • Required for all release-type studies exploring new targets Example: 17F at REX ISOLDE produced from sub-mm SiC target for Astrophysics. Production tests involved implantation depth dependences for release properties A. Herlert ISCC February 4, 2010 Solid state Physics: maybe, but probably not with current setup Majority of current experiments do not require post-acceleration: • Post-implantation, most experiments require annealing to repair implantation damage. This diffuses ions further into the material (generally, rare earths in Si an exception). • For samples studied using optical spectroscopy (e.g. ZnO), too deep can be a disadvantage as laser only absorbed within 100s of nms from surface. • Recent experimental demands have been for beam retardation rather than post-acceleration. Where it could be useful: • In principle, better focussing of the beam. • Implantation into specific layer of multi-layered structure. • For electrical measurements of semiconductors: implantation deeper removes possible surface effects. • b-NMR studies for solid state physics. A. Herlert ISCC February 4, 2010 Possible alternatives? • Construct more user-friendly setup at one of the GPS collection points? • New solid state physics BMBF proposal describes a new collection chamber. Could, in principle, be modified to accommodate postacceleration. • Smaller form factor, more standardized components… • Older plans were drawn up to enhance existing setup by taking highly-charged EBIS beams to reach higher energies…2 most realistic options were: • e.g. after old ECR on GHM was mooted, but this opportunity has been lost. • Or to left of REX LINAC, area around ASPIC/TAGS, space and existing installations a problem though. In summary, HVP would be welcome for users – especially for target development – but not sure if investing in current setup is the best way to proceed However, very important to retain collection point on HRS A. Herlert ISCC February 4, 2010 New location for HV platform ? MISTRAL MINIBALL ISOLTRAP Em Ch WITCH A. Herlert b ISCC February 4, 2010 Status ISOLDE web page New web page presently located at: http://isolde.web.cern.ch/ISOLDE/isoldenewweb Will be moved to new location next week http://isolde.web.cern.ch/ISOLDE/ Many pages still not up to date Work in progress – Suggestions are appreciated A. Herlert ISCC February 4, 2010