Looking for WIMP Dark Matter using Ultra-Cold Detectors and Other Techniques
Dan Akerib Case Western Reserve University CDMS Collaboration
APS Meeting / Session H3 Jacksonville, Florida 15 April 2007 Dynamical Evidence: Galaxy clusters
Colley, Turner & Tyson Clusters – 1-10 Mpc
Independent methods: Lensing
Virial thm:
! "m = "/"crit = 0.30 ± 0.03 ! dark matter dominates
"dark > 30 "lum Tyson, Dell'Antonio, Kochanski Dan Akerib Case Western Reserve University Standard Cosmology
Colley, Turner & Tyson from Perlmutter, Phys. Today (units of critical density)
WMAP WMAP Tytler & Burles Dan Akerib APS Jacksonville 2007 Case Western Reserve University Non-Baryonic Dark Matter
Production = Annihilation (T!m ) • Matter density # ! !Matter = 0.30 ± 0.04 Production suppressed (T
! TFO ~ m/20 Comoving Number Density ! !A " electroweak scale SUSY/LSP 1 10 100 1000 m# / T (time ") Dan Akerib APS Jacksonville 2007 Case Western Reserve University SUSY Dark Matter: elastic scattering cross section
-40 10 http://dmtools.brown.edu/ Gaitskell&Mandic • The ‘standard’ progress plot ! -42 Direct-search experimental bounds 10 • Theory ! Sample SUSY parameter space -44 10 ! Apply accelerator and model-specific ] (normalised to nucleon) 2 particle physics constraints
! -46 Apply cosmological bound on relic density 10 ! Extract allowed region for WIMP-nucleon ILC LHC
Cross-section [cm -48 10 060227062301 cross-section versus WIMP mass 2 4 10 10 WIMP Mass [GeV] DATA listed top to bottom on plot CRESST 2004 10.7 kg-day CaWO4 Edelweiss I final limit, 62 kg-days Ge 2000+2002+2003 limit Broad theoretical landscape: DAMA 2000 58k kg-days NaI Ann. Mod. 3sigma w/DAMA 1996 ZEPLIN I First Limit (2005) CDMS (Soudan) 2004 + 2005 Ge (7 keV threshold) much of it testable with next Bottino et al. Neutralino Configurations (OmegaWIMP < OmegaCDMmin) Bottino et al. Neutralino Configurations (OmegaWIMP >= OmegaCDMmin) x x x Guidice and Romanino, 2004, mu < 0 and next-next generation DM A. Pierce, Finely Tuned MSSM Guidice and Romanino, 2004, mu > 0 Chattopadhyay et. al Theory results - post WMAP searches and/or next and next- Baltz and Gondolo, 2004, Markov Chain Monte Carlos (1 sigma) Baer et. al 2003 Kim/Nihei/Roszkowski/de Austri 2002 JHEP x x x Ellis et. al Theory region post-LEP benchmark points next generation accelerators Baltz and Gondolo 2003 Baltz and Gondolo, 2004, Markov Chain Monte Carlos 060227062601 Dan Akerib APS Jacksonville 2007 Case Western Reserve University WIMPs in the Galactic Halo
WIMP detector • data
– bulge, disk & halo
– bulge & disk energy transferred appears in ‘wake’ of recoiling nucleus WIMP-Nucleus Scattering
halo Scatter from a Nucleus in a Terrestrial bulge Particle Detector sun disk "E#~ 30 keV ! < 0.1/kg/day Log(rate)
The Milky Way Erecoil Dan Akerib APS Jacksonville 2007 Case Western Reserve University WIMPs in the Galactic Halo
WIMP detector • Exploit movements of Earth/ Sun through WIMP halo ! Direction of recoil -- most events should be opposite Earth/Sun direction (Spergel 1988) energy transferred appears in ‘wake’ of recoiling nucleus ! Annual modulation -- harder spectrum when Earth travels with WIMP-Nucleus Scattering sun (Drukier, Freese, & Spergel 1986) Scatter from a Nucleus in a Terrestrial Particle Detector
galactic center ~2% seasonal June Dec effect Dec. Sun 230 km/s June Log(rate)
Erecoil Dan Akerib APS Jacksonville 2007 Case Western Reserve University The Signal and Backgrounds
Signal (WIMPs) Background (gammas/betas)
Nucleus Electron Recoils Recoils v/c ! 7"10-4 v/c ! 0.3 Er ! 10’s KeV
Neutrons also interact with nuclei, but mean free path a few cm !0 "
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Nuclear-Recoil Discrimination
• Nuclear recoils vs. electron recoils !" Division of energy WIMP !" Timing !" Stopping power
10% energy Ionization
Target Phonons/heat
100% energy slowest cryogenics
Light
1% energy fastest no surface effects WIMP
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Nuclear-Recoil Discrimination
• Nuclear recoils vs. electron recoils !" Division of energy WIMP !" Timing !" Stopping power CDMS II, Background
ionization Signal EDELWEISS I E 10% energy CDMS II, E Ionization phonons EDELWEISS II +timing
Target Phonons/heat
100% energy slowest cryogenics
Light
1% energy fastest no surface effects WIMP
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Nuclear-Recoil Discrimination
• Nuclear recoils vs. electron recoils !" Division of energy WIMP !" Timing !" Stopping power CDMS II, Background
ionization Signal EDELWEISS I E 10% energy CDMS II, E Ionization phonons EDELWEISS II +timing
Target Phonons/heat
100% energy slowest cryogenics
Light 1% energy CRESST II Background
fastest light
no surface effects E Signal WIMP Ephonons
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Nuclear-Recoil Discrimination
• Nuclear recoils vs. electron recoils !" Division of energy WIMP !" Timing !" Stopping power CDMS II, Background
ionization Signal EDELWEISS I E 10% energy CDMS II, E Ionization phonons EDELWEISS II +timing
ZEPLIN II/III/Max, Target XENON, LUX, Phonons/heat WARP, ArDM 100% energy slowest cryogenics
Light 1% energy CRESST II Background
fastest light
no surface effects E Signal WIMP Ephonons
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Nuclear-Recoil Discrimination
• Nuclear recoils vs. electron recoils !" Division of energy WIMP !" Timing !" Stopping power CDMS II, Background
ionization Signal EDELWEISS I HPGe expts E 10% energy CDMS II, E Ionization phonons EDELWEISS II +timing
Picasso, ZEPLIN II/III/Max, Target Simple, XENON, LUX, Phonons/heat Coupp WARP, ArDM 100% energy (superheated) slowest cryogenics
Light DAMA/LIBRA 1% energy CRESST II Background
KIMS ZEPLIN-I, fastest light
DEAP, CLEAN, no surface effects E Signal WIMP XMASS Ephonons +timing Dan Akerib APS Jacksonville 2007 Case Western Reserve University Background suppression: Recoil Discrimination
WIMPs ‘look’ different – recoil discrimination Photons and electrons scatter from electrons WIMPs (and neutrons) scatter from nuclei
In CDMS, EDELWEISS, CRESST: (light replaces charge)
Background eld i Y Background charge E Signal
Signal Charge
Ephonons Erecoil
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Background suppression: Recoil Discrimination
WIMPs ‘look’ different – recoil discrimination Photons and electrons scatter from electrons WIMPs (and neutrons) scatter from nuclei CDMS
Gammas
Background eld i Y Background charge E Signal
Signal Charge Neutrons
Ethermal Erecoil
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Background suppression: Recoil Discrimination
WIMPs ‘look’ different – recoil discrimination Photons and electrons scatter from electrons WIMPs (and neutrons) scatter from nuclei >50000:1 rejection CDMS
Gammas
Background eld i Y Background charge E Signal
Signal Charge
Ethermal Erecoil
Dan Akerib APS Jacksonville 2007 Case Western Reserve University CDMS: Cryogenic “ZIP” detectors
Superconducting films that detect minute amounts of heat Transition Edge Sensor sensitive to fast athermal phonons
~ 10mK 1 !m tungsten 4 aluminum fins RTES (!) 3
2
1
Tc ~ 80mK T (mK) Ionization measurement Dan Akerib APS Jacksonville 2007 Case Western Reserve University Surface backgrounds: low-energy betas
• electrons that interact in surface “dead layer” of detector result in reduced ionization yield
Nuclear-recoil WIMP-signal region
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Overall Strategy: gammas, betas, neutrons
Soudan Mine Underground muon veto Laboratory polyethylene moderator
Cu. Ft. <50mK
2000 mwe depth
gamma cal. y Phonon timing = Charge/phonons Y x Erecoil (keV) Y = Charge/phonons Dan Akerib Case Western Reserve University Mask signal region: Blind analysis to minimize bias
• Cuts set on calibration data and non-masked FET WIMP-search data ! timing parameter T1 T2 SQUID ! ionization yield ! problem detectors/channels
Calibration data in Detector T2Z3 (Ge)
133Ba gammas
133Ba surface betas Tc Gradient noisy
“bad” region 14C contam. 252Cf neutrons
= Ge = Si Dan Akerib APS Jacksonville 2007 Case Western Reserve University Most recent Soudan WIMP-search data: 2 towers
Before timing cuts After timing cuts 1.5 1.5 Z2/Z3/Z5/Z9/Z11
1.0 1.0 ield ield Y Y
0.5 0.5 Ionization Ionization 1 candidate (bad run) 0.0 Z2/Z3/Z5/Z9/Z11 0.0 near-miss 0 10 20 30 40 50 60 70 80 90 100 0 10 20 30 40 50 60 70 80 90 100 Recoil Energy (keV) Recoil Energy (keV) ESTIMATED BKG: 0.4 ± 0.2 (sys.) ± 0.2 (stat.) electron recoils, 0.05 (Geant3) ! 0.005 (Geant4/Fluka/MCNPX) neutron recoils. 34 kg-d after cuts Optimized for ~0.5 background events Dan Akerib APS Jacksonville 2007 Case Western Reserve University Candidate event: Got WIMP? No...
• Automatic LED flash every 4 hours to discharge trapping sites 133 • The one candidate event Ba calibration comes from a run with poor neutralization! ! anomalous population of low-yield events ! improved screening for next run
! anyway, consistent with Ionization yield background !
included (worsen) upper LED neutralization limit on cross section candidate event
Time of day (hours) Dan Akerib APS Jacksonville 2007 Case Western Reserve University Previous Soudan Run: first tower only
Before timing cuts After timing cuts
10.4 keV Gallium line Z2/Z3/Z5
1 nuclear-recoil candidate, Z2/Z3/Z5 consistent with backgrounds
0.7 ± 0.35 misidentified electrons (w/Z1) 19 kg-d after cuts 0.02 (G3) ! 0.002 (G4/Fluka/Mcnpx) neutron recoils (w/ Z1)
Dan Akerib APS Jacksonville 2007 Case Western Reserve University 1st Year CDMS Soudan Combined Limits
90% CL upper limits assuming Upper limits on the 2 • standard halo, A scaling (Spin. Ind.) WIMP- nucleon cross section are 1.7!10-43 cm2 for a WIMP with mass of 60 GeV/c2 ! Factor 8 lower than any other experiment • Excludes regions of
] (normalized to nucleon) SUSY parameter space 2 DAMA under some frameworks ! Bottino et al. 2004 in magenta (relax GUT Unif.) ! Ellis et al. 2005 Cross section [cm (CMSSM) in green
WIMP Mass [GeV/c2 ] 2-tower and combined (53 kg-d): PRL 96, 011302 (2006) 1-tower (19 kg-d): PRL 93, 211301 (2004); PRD 72, 052009 (2005) Dan Akerib APS Jacksonville 2007 Case Western Reserve University 1st Year CDMS Soudan Combined Limits
90% CL upper limits assuming Upper limits on the 2 • standard halo, A scaling (Spin. Ind.) WIMP- nucleon cross section are 1.7!10-43 DAMA Na ann. mod. 2 (Gondolo/Gelmini) cm for a WIMP with mass of 60 GeV/c2 ! Factor 8 lower than any other experiment DAMA 7-year NaI, Riv. Nuovo Cim.• 26N1,2003Excludes (astro-ph/0307403) regions of
] (normalized to nucleon) SUSY parameter space 2 DAMA under some frameworks ! Bottino et al. 2004 in magenta (relax GUT Unif.) ! Ellis et al. 2005 Cross section [cm (CMSSM) in green
WIMP Mass [GeV/c2 ] 2-tower and combined (53 kg-d): PRL 96, 011302 (2006) 1-tower (19 kg-d): PRL 93, 211301 (2004); PRD 72, 052009 (2005) Dan Akerib APS Jacksonville 2007 Case Western Reserve University DAMA: NaI & Annual Modulation
June June Dec Dec Dec WIMP Signal
June June ±2% Background Dec Dec Dec
100-kg detector mass: measure energy for each event, but no rejection of gamma background
Dan Akerib APS Jacksonville 2007 Case Western Reserve University CDMS Soudan Limits and DAMA
90% CL upper limits assuming standard halo, A2 scaling (Spin. Ind.) 6-! DAMA Na ann. mod. (Gondolo/Gelmini)
DAMA 7-year NaI, Riv. Nuovo Cim. 26N1,2003 (astro-ph/0307403) ] (normalized to nucleon) 2 DAMA • Iodine-based annual modulation not compatible • Alternate interpretation: Sodium for low mass Cross section [cm almost ruled out Further tests for Spin- WIMP Mass [GeV/c2 ] • Dependent couplings...
Dan Akerib APS Jacksonville 2007 Case Western Reserve University DAMA ! LIBRA
• LIBRA ! Large sodium Iodide Bulk for RAre processes ! 250 kg with improved radiopurity ! Operating since 2003 • Further R&D toward 1-ton ! NaI(Tl) radiopurification started
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Completing CDMS-II at Soudan
Bulk n.r.’s 5-towers at Soudan
• Continue running with zero expected background Surface e.r.’s ! Improved analysis ! Cleaner towers • 4 kg Ge • 0.9 kg Si timing parameter (!s) ! 4x data in hand ! On track for 8x by Bulk n.r.’s early ‘08
CDMS Combined Surface e.r.’s
!!2 (!-n) Dan Akerib APS Jacksonville 2007 Case Western Reserve University Next for CDMS: SuperCDMS 25 kg • Proposed 25-kg experiment based on -40 10 http://dmtools.brown.edu/ updated 42 x 600-g Ge ZIPs Gaitskell&Mandic ! 120x beyond current limits -42 ! 15x beyond CDMS-II goal 10 ! Approved for space at SNOLAB -44 ! 10
Next step towards ton-scale goal ] (normalised to nucleon) 2 Detector fab/demonstration underway • -46 10
Cross-section [cm -48 10 060227062301 2 4 10 10 WIMP Mass [GeV] nuc. rec. 1”-thick 0.6-kg: 3x fiducial mass per s.a.
surface
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Edelweiss-I in Frejus Tunnel: “1 kg” stage
• First data taking in Fall 2000 at 4800 mwe depth • Detector improvements: 2nd data set early 2002 • 3rd data taking: October 2002 - March 2003
Archeological lead
3 * 320 g Ge detectors: heat and ionization simultaneous readout (NTD thermistor) Installed May 2002
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Edelweiss-I: Recoil discrimination
Gamma calibration Neutron calibration
Nuclear recoil discrimination down to 20 keV threshold !-ray rejection > 99.99 %
Dan Akerib APS Jacksonville 2007 Case Western Reserve University EDELWEISS-I results
• 2000-2003: Exposure of ~60 kg-d ! Three nuclear recoil candidates (30-100keV) consistent with neutron bkg WIMP search data (partial) WIMP cross section limit
WEISS-I EDEL
CDMS-II (1st tower)
Low-yield surface recoils Phys. Rev. D71, 122002, 2005 (astro-ph/0503265) Dan Akerib APS Jacksonville 2007 Case Western Reserve University Edelweiss-II • 100-detector cryostat operating in Modane • Commissioning run completed w/7 detectors • 26 detectors now cold ! ~10-44 cm2: ! 22 x 320-g NTD on Ge: improved charge collection ! 4 x 400-g NbSI on Ge: metal-insulator transition - fast timing for surface/bulk event discrimination ! Commissioning started in Feb 07 • Plan to propose expansion to 100-module array
7 NbSI on Ge 6
5 Surface event 4
3
2 Bulk event
1
0 0 2 4 6 8 10 12 14 16 Time (ms)
Dan Akerib APS Jacksonville 2007 Case Western Reserve University CRESST II: Phonons and Scintillation
• Nuclear recoils have much smaller hep-ex/9904005 light yield than electron recoils
• Photon and electron interactions ) can be distinguished from nuclear ee recoils (WIMPs, neutrons) Light (keV
Particle Thermometer
Light Detector
Mirror Phonons (keV)
Performance from a 6-g CaWO4 prototype ! Very small scintillation signal for tungsten recoils ! Thermometer Scaled up to 300g detectors Phonon Detector Dan Akerib APS Jacksonville 2007 Case Western Reserve University CRESST II: Phonons and Scintillation
Results from 20.5 kg-d exposure of two 300-g CaWO4 prototypes !" No neutron shielding !" Observe low-yield events consistent with neutron rates and oxygen cross section & light yield !" No tungsten recoils in light yield region below oxygen yield (consistent with noise )
CRESST all
-only CRESST W WEISS-I EDEL
CDMS-II (1st tower)
Astropart. Phys. 23, 325-339, 2005 (astro-ph/0408006) Dan Akerib APS Jacksonville 2007 Case Western Reserve University CRESST II Status and Plans
Shielded cryostat • 2-year upgrade nearly complete: ! Installed neutron moderator, muon veto, new 66-SQUID channel readout for up to 33 detector modules / 10 kg target mass ! New DAQ is installed ! Electronics, detector holder system in progress ! Commissioning with 8 detectors (2.4 kg)
• With EDELWEISS, formed EURECA collaboration ! ton- PE neutron moderator scale experiment Plastic scintill. !-veto
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Superheated liquids: immune to EM backgrounds
• Principle: Superheated liquid ! Requires nucleation energy to overcome surface tension and form bubble ! Tune thermodynamic parameters • Insensitive to min. ionizing and low-energy electron recoils • Sensitive to higher-energy- density nuclear recoils ! Threshold detector - release of stored energy enhances observability
Dan Akerib APS Jacksonville 2007 Case Western Reserve University Superheated Droplet Detectors: PICASSO and SIMPLE
Piezo-electric readout • Superheated droplets, eg, freon, in a passive gel matrix – neutron dosimetry ! Only high-ionization energy density tracks – nuclear recoils, alphas – sufficient to cause nucleation (PICASSO) (droplet explosion) ! Insensitive to gammas, betas, & minimum ionizing particles ! Freon: 19F – high SD coupling • Challenges ! Energy information – vary temperature in threshold detector ! Develop large-A nucleus for spin- independent coupling ! Mass scale up ! Radiopurity of gel matrix (alphas) microscopic bubble chambers
Dan Akerib APS Jacksonville 2007 Case Western Reserve University PICASSO Spin-Dependent WIMP limits
-30 Proton coupling -30 Neutron coupling 10 http://dmtools.brown.edu/ 10 http://dmtools.brown.edu/ Gaitskell&Mandic Gaitskell&Mandic
CDMS-Si CRESST ZEPLIN DAMA PICASSO CRESST CDMS-Ge -35 -35 10 PICASSO 10 CDMS-Si ZEPLIN ] (normalised to nucleon) NAIAD ] (normalised to nucleon) 2 2 DAMA CDMS-Ge
PICASSO: 50x mass SuperK increase soon in -40operation - results -40 From module with 10 10 expected in 2007 20-g active mass Cross-section [cm 060205123501 Cross-section [cm 060205121101 0 2 4 0 2 4 10 10 10 10 10 10 WIMP Mass [GeV] WIMP Mass [GeV]
When spin independent coupling suppressed, rate dominated by axial coupling to unpaired nucleon (DAMA regions from Savage, Gondolo and Freese) Dan Akerib APS Jacksonville 2007 Case Western Reserve University SIMPLE Spin-Dependent WIMP limits
-30 Proton coupling Model independent (projected) 10 http://dmtools.brown.edu/ (a la D.R. Tovey et al. Physics Letters B 488(2000)) Gaitskell&Mandic
CDMS-Si ZEPLIN CRESST CDMS-Ge -35 DAMA/NaI 10 PICASSO
] (normalised to nucleon) SIMPLE NAIAD 2 DAMA
SuperK SIMPLE: -40 10 0.42 kg-d
Cross-section [cm 060903093701 T.A. Girard 0 2 4 10 10 10 Goal is 30-100 kg-d C2ClF5 WIMP Mass [GeV] exposure in 2007, and further development towards 10 kg-d CF3I When spin independent coupling SIMPLEsuppressed, & PICASSO rate – technical dominated exchanges, by axial coupling to unpaired nucleonand MOU for joint for scale-up (DAMA regions from Savage, Gondolo and Freese) Dan Akerib APS Jacksonville 2007 Case Western Reserve University COUPP: Bubble Chamber Revival
• 2-kg CF3I Bubble Chamber – U. of Chicago, U. of Indiana/South Bend, and Fermilab Installed at 300 mwe depth at FNAL • Tune thermodynamic parameters — First results in preparation immunity to elec. recoils: 1010 gamma rejection! • Two principal challenges: ! passivate nucleation from vessel walls ! trigger rate ~ laboratory neutron background ! ! internal alpha backgrounds - work in progress • 80 kg mass target under construction ! FNAL experiment E961
Quadruple neutron-scatter event http://www-coupp.fnal.gov/
Dan Akerib APS Jacksonville 2007 Case Western Reserve University KIMS Experiment: CsI(Tl)
• Korea Invisible Mass Search • Similar to DAMA but CsI Success in reducing intrinsic 3-4 keV 4-5 keV 2 • 102 10 radiocontaminants
10 ! 137Cs - water purity during prep events 10 events ! 87 Rb - reduced through repeated re- 1 1 crystalization -1 -0.5 0 0.5 1 1.5 -1 -0.5 0 0.5 1 1.5 log(MT) log(MT) • New results from 35 kg 5-6 keV 6-7 keV ! 2 4 x 8.7 kg crystals 2 10 10 ! 3409 kg-days 10 • Building 100 kg array events 10 events ! 1 target of 2 cts/(keV kg day) 1 -1 -0.5 0 0.5 1 1.5 -1 -0.5 0 0.5 1 1.5 • Cross check of DAMA log(MT) log(MT) ! Iodine couplings ! electron recoils (gamma cal.) nuclear recoils (neutron cal.) ! annual modulation ! $ WIMP search
Phys. Lett. B633 (2006), 201-208 and arXiv:0704.0423 (new 35-kg results) Dan Akerib APS Jacksonville 2007 Case Western Reserve University KIMS Experiment: CsI(Tl)
• Korea Invisible Mass Search Similar to DAMA but CsI • Direct crosscheck on SI Iodine coupling • Success in reducing intrinsic 10-3 radiocontaminants ! 137Cs - water purity during prep ! 87Rb - reduced through repeated re- 10-4 crystalization
NAIAD 12523 kg days • New results from 35 kg ZEPLIN I 10-5 ! 4 x 8.7 kg crystals KIMS 3409 kg days CRESST ! 3409 kg-days X-section (pb) EDELWEISS
CDMS (2005) Building 100 kg array -6 • 10 ! target of 2 cts/(keV kg day) • Cross check of DAMA ! Iodine couplings 10-7 102 103 104 ! annual modulation WIMP Mass (GeV)
Phys. Lett. B633 (2006), 201-208 and arXiv:0704.0423 (new 35-kg results) Dan Akerib APS Jacksonville 2007 Case Western Reserve University KIMS Experiment: CsI(Tl)
• Korea Invisible Mass Search Similar to DAMA but CsI • Best limit on SD proton coupling • Success in reducing intrinsic 102 radiocontaminants ! 137Cs - water purity during prep ! 87Rb - reduced through repeated re- 10 CDMS Ge (2005) PICASSO (2005) crystalization DAMA region • New results from 35 kg SIMPLE (2005) ! 1 4 x 8.7 kg crystals NAIAD (2005) ! 3409 kg-days X-section (pb) KIMS 3409 kg days Building 100 kg array • 10-1 ! target of 2 cts/(keV kg day) • Cross check of DAMA ! Iodine couplings 10-2 102 103 104 ! annual modulation WIMP Mass (GeV)
Phys. Lett. B633 (2006), 201-208 and arXiv:0704.0423 (new 35-kg results) Dan Akerib APS Jacksonville 2007 Case Western Reserve University Summary
• Dark matter remains a fundamental mystery ! Possible solution lies in new fundamental -40 particle physics 10 http://dmtools.brown.edu/ Gaitskell&Mandic • Establishing a concordant model requires laboratory and astrophysical meas. -42 10 — particle mass, lifetime, relic density, halo ! Astro. signal from annihilation products -44 Significant recent advances in 10 ] (normalised to nucleon)
• 2 sensitivity -46 ! Cryogenic expts: ongoing data runs 10 ! Several new technologies (+see next talk!)
! Cross-section [cm -48 Cross check of DAMA nearly complete 10 060227062301 2 4 ! 10 10 Followup with directional detectors (e.g., WIMP Mass [GeV] DRIFT) - galactic origin ! Next 5-10 years looks very exciting!
Dan Akerib APS Jacksonville 2007 Case Western Reserve University The CDMS Collaboration
Brown University Santa Clara University R.J. Gaitskell, J.P. Thompson, M. Attisha B.A. Young Caltech Stanford University Z. Ahmed, S. Golwala, G. Wang J. Cooley-Sekula, P.L. Brink, B.Cabrera, Case Western Reserve University C. Chang, W. Ogburn, M.Pyle, S. Yellin D.S. Akerib, C.N. Bailey, M.R. Dragowsky, University of California, Berkeley D.R. Grant, R. Hennings-Yeomans, M. Daal, J. Fillipini, N. Mirabolfathi, R.W. Schnee B. Sadoulet, D. Seitz, B.Serfass, Fermi National Accelerator Laboratory K. Sundquist D.A. Bauer, F. DeJongh, M. Crisler, J. Hall, University of California, Santa Barbara D. Holmgren, E. Ramberg, J. Yoo R. Bunker, D.O. Caldwell, H. Nelson, Nat’l Institute of Standards & Tech. J. Sander, R. Mahapatra K. Irwin University of Aachen-RWTH University of Colorado at Denver M. E. Huber S. Arrenberg, L. Baudis, T. Bruch, M. Tarka University of Minnesota P. Cushman, L. Duong, A. Riesetter, University of Florida X. Qiu S. LeClercq, T. Saab With thanks to NSF and DOE... Thank you…
Dan Akerib APS Jacksonville 2007 Case Western Reserve University