SNII Meeting, UCLA N.J.T.Smith: RAL PPD Boulby Facility and Programme N.J.T.Smith Rutherford Appleton Laboratory. Facilities and Expeiments at the U.K. Boulby Mine Facilities and Expeiments at the U.K. Boulby Mine Current facilities JIF Expansion Experimental Programme Current facilities JIF Expansion Experimental Programme

SNII Meeting, UCLA N.J.T.Smith: RAL PPD BDMC Collaboration QMW: J. C. Barton University of Surrey: E. Morton, P. Sellin CERN/Padova: A PietropauloITEP: D Akimov, V Lebedenko, A Danilov Coimbra: A Policarpo, M Salete Leite, R Ferreira Marques, V Chepel UCLA: D Cline, M Atac, H Wang, J K Woo, J ParkColumbia: C Hailey, J Hong, E Aprile, A Castellina UCSD: K Griest, G Masek, K BucklandTemple University: C J Martoff, P Ambrozewicz, E Kaczanowicz University of Sheffield: T. Gamble, V. A. Kudryavtsev, T. B. Lawson, M. J. Lehner, P. K. Lightfoot, J. E. McMillan, B. Morgan, M. Robinson, N. J. C. Spooner, L.. Thompson, D. R. Tovey Rutherford Appleton Laboratory: G. J. Alner, E.G. Capocci, S. P. Hart, J. D. Lewin, R. Lüscher, R. M. Preece, J. W. Roberts, N. J. T. Smith, P.F. Smith Imperial College of Science, Technology and Medicine: B. Ahmed, A. Bewick, D. Davidge, J. V. Dawson, A. S. Howard, I. Ivaniouchenkov, W. G. Jones, M. K. Joshi, V. Lebedenko, I. Liubarsky, T. J. Sumner, J. J. Quenby Torino: P Picchi, L Periale, G Mannocchi, C Taricco, C Castagnoli, A Curioni Saclay: G. Gerbier Occidental College: D Snowden-Ifft, T Ohnuki, N Villaume, J Burwell LLNL: B Craig, M J Lehner

SNII Meeting, UCLA N.J.T.Smith: RAL PPD UK(B)DMC Programme NaI small array 20 kg NAIAD high rate array 50 kg UK-Saclay 20 kg (1) NAIAD array array existing ZEPLIN-I single phase PSD 4 kg ZEPLIN-II ion-scint two phase Xe 30 kg ZEPLIN-III Ion-scint two phase Xe high field 6 kg (2) ZEPLIN array array under construction existing under construction DRIFT 1 directional 1 m 3 (3) DRIFT array array ramp down ZEPLIN-AXE ion-scint two phase Xe 1000 kg MULTINATIONAL concept DRIFT 10 directional 10 m 3 MULTINATIONAL concept

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Boulby Potash Mine Working potash / rock salt mineWorking potash / rock salt mine Easily modified cavern structureEasily modified cavern structure

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Boulby U/G Facilities 50m Stub 2 Stub 2a ‘H’ Area JIF Area m m m m 2

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Cosmic Ray  Flux Cosmic ray  generate neutrons through spallation and evaporationCosmic ray  generate neutrons through spallation and evaporation Surface  flux attenuated by 10 6Surface  flux attenuated by 10 6 Comparable to Kamioka and Gran SassoComparable to Kamioka and Gran Sasso

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Neutron Backgrounds U and Th contaminationU and Th contamination –alpha interactions and fission (10 -5 of  flux) Cosmic ray muonsCosmic ray muons –spallation and evaporation

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Gamma Backgrounds Cavern radioisotope impuritiesCavern radioisotope impurities –Halite intrinsically low U/Th levels Low radon levels comparable to Gran Sasso ~5 Bqm -3Low radon levels comparable to Gran Sasso ~5 Bqm -3 NaI Detector total event ratesNaI Detector total event rates –Unshielded: >2e5 kg -1 day -1 –Shielded: 6e3 kg -1 day -1

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Gran Sasso Comparison

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Boulby Potash Mine

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Stub 2 Pre-JIF

SNII Meeting, UCLA N.J.T.Smith: RAL PPD JIF Expansion JIF (Round2) SuccessfulJIF (Round2) Successful Surface facilitiesSurface facilities –Workshop, offices, etc. Underground facilitiesUnderground facilities –New clean area, upgrade existing

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Area Locality

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Construction Technique ZEPLIN NaI 20m Dirty Stores Electric Darkrm Clean Room Experimental Halls - partitioned as required Mess/ Change Stores Wshop Control Room Transfer Clean-off 8m 20m 47m 14m 8m 6m Running boards

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Boulby Surface Building

SNII Meeting, UCLA N.J.T.Smith: RAL PPD They never told me this….

SNII Meeting, UCLA N.J.T.Smith: RAL PPD DAMA Annual Modulation Gran Sasso: 9 x 9.7kg Gran Sasso: 9 x 9.7kg crystals. –Annual modulation few % of signal High energy (>90keV) no modulation, rate  = 0.1%High energy (>90keV) no modulation, rate  = 0.1% No recoil discrimination –PMT noise rejection INFN/AE-00/01

SNII Meeting, UCLA N.J.T.Smith: RAL PPD DAMA 1-2 Rates (replotted) Gaitskell 1999 Expected WIMP Recoil spectrum Average over all crystals Modulation in Low energy bins - threshold fluctuation?

SNII Meeting, UCLA N.J.T.Smith: RAL PPD NaI unencapsulated crane glove box NaI encapsulated to JIF area H area H 1 H 2 crystal NaIAD unitstatus DM68NaIAD-1removed DM74NaIAD-2running DM72NaIAD-3running DM75NaIAD-4running DM76NaIAD-5running DM77NaIAD-6running DM78NaIAD-7returned DM79NaIAD-8testing DM80NaIAD-9order DM81NaIAD-10collab DM48back-up testing Status as 09/00 control room + daq NaAID Programme 35 kg Unencapsulated surface controlled NaI35 kg Unencapsulated surface controlled NaI 15 kg Encapsulated high light yield NaI15 kg Encapsulated high light yield NaI 20kg Saclay crystal20kg Saclay crystal

SNII Meeting, UCLA N.J.T.Smith: RAL PPD CDMS Results Thermal/ionisation Ge/Si detectorsThermal/ionisation Ge/Si detectors Ge: 10.6 kg-day, 13 nuclear recoils, 4 multiple scattersGe: 10.6 kg-day, 13 nuclear recoils, 4 multiple scatters Si: 1.6 kg-day, 4 nuclear recoilsSi: 1.6 kg-day, 4 nuclear recoils Gammas (source) Neutrons (source) Phonon threshold Gammas Nuclear recoils Surface electrons Data Calibration

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Current Direct Detection Limits Sensitivity ≈ pbSensitivity ≈ pb –DAMA: annual modulation of rate –CDMS: neutron background subtraction –UKDMC: ‘anomalous’ events preclude limit

SNII Meeting, UCLA N.J.T.Smith: RAL PPD ZEPLIN I Xe * +Xe Xe 2 * Triplet 27ns Singlet 3ns 2Xe 175nm Xe ** + Xe Xe 2 + +e - (recombination) Xe + +Xe

SNII Meeting, UCLA N.J.T.Smith: RAL PPD ZEPLIN I Underground Pb shielding Top of ZEPLIN I veto Boulby stub 2 laboratory xenon purification Stable operation demonstrated Counts vs. time Xe temp vs. time room temp vs. time

SNII Meeting, UCLA N.J.T.Smith: RAL PPD More Photos

SNII Meeting, UCLA N.J.T.Smith: RAL PPD U/G Results - ZEPLIN I 85 Kr < atoms/atom Not optimum performance

SNII Meeting, UCLA N.J.T.Smith: RAL PPD ZEPLIN II Design Scintillation/Ionisation detector: proven technologyScintillation/Ionisation detector: proven technology Two phase operationTwo phase operation –Ionisation from electroluminescence in gas region 30kg target under construction30kg target under construction Deploy 2001/2Deploy 2001/2 7x 5” PMTs7x 5” PMTs PTFE LinerPTFE Liner –Improve light yield –Define E-field PMT Gas phase Liquid target

SNII Meeting, UCLA N.J.T.Smith: RAL PPD ZEPLIN III Design Scintillation/ionisation detectorScintillation/ionisation detector High E-fieldHigh E-field –Ionisation from nuclear recoils 1kg test chamber1kg test chamber 6kg LXe target6kg LXe target Under constructionUnder construction Deployment 2001/2Deployment 2001/2 Compton vetoCompton veto 19x 2” PMTs19x 2” PMTs –Fast timing –Additional discrimination –Position information

SNII Meeting, UCLA N.J.T.Smith: RAL PPD DRIFT: low pressure gaseous TPCDRIFT: low pressure gaseous TPC –Recoil direction correlation –CS 2 minimises diffusion 1 foot cube foot cube –99.9% gamma rejection –95% alpha rejection (from wires) DRIFT 1m 3 Module under constructionDRIFT 1m 3 Module under construction –200  m wire chamber 2cm pitch –20  m MWPC readout 2mm pitch CS 2 +Xe,Ar at TorrCS 2 +Xe,Ar at Torr DRIFT Design gammas recoil discrimination C recoils S recoils gammas recoil discrimination gammas alphas S recoil region (>90%) alpha discrimination

SNII Meeting, UCLA N.J.T.Smith: RAL PPD Boulby Facility and Programme Boulby Mine Facility StatusBoulby Mine Facility Status –Deep site –Medium scale experiments –Original areas refurbished –JIF funded facility Surface facility started (Jun 2001) U/G facility designed (Nov 2001) Boulby Experimental StatusBoulby Experimental Status –UKDMC: NaI DAMA assessment –BDMC: NaIAD, ZEPLIN, DRIFT ZEPLIN I : 2000 ZEPLIN II/III:2001/2 DRIFT: Limits expected from current detectors Limits expected from future detectors (known technology)