Dark Matter -- Astrophysical Evidences and Terrestrial Searches

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1 Dark Matter -- Astrophysical Evidences and Terrestrial Searches Klaus Eitel, Karlsruhe Institute of Technology, KCETA, IK KIT University of the State of Baden-Württemberg and National Large-scale Research Center of the Helmholtz Association

2 Content of the lecture Lecture 1: Lecture 2: Lecture 3: Lecture 4: review of astrophysical evidences for DM cosmological LCDM concordance model structure formation DM in our neighbourhood DM particle candidates: axions, neutralinos,... interaction models of DM with ordinary matter indirect detection (cc annihilation) & production direct detection strategies methods of direct detection general challenges experiments for direct search (I) experiments for direct search (II) results evidences? direct indirect production actual status (and outlook) 2 Klaus Eitel BOSEN workshop 29 August 3 September 2010

3 direct DM search detection schemes HDMS CoGeNT COUPP Picasso Ge, CF 3 I, C 4 F 10 10% energy Ionization WIMP via elastic scattering off nuclei Ge, Si Edelweiss, CDMS 3 WArP, ArDM liquid Xe/Ar Zeplin-3, LUX, Xenon-10/100 NaI, liqu.xe Target Light 1% energy fastest no surface effects DAMA, Libra, Zeplin-1, XMASS, KIMS, ANAIS Klaus Eitel BOSEN workshop 29 August 3 September 2010 WIMP Heat 100% energy slowest cryogenics CaWO 4, BGO Al 2 O 3, LiF CRESST-1 CRESST-2

4 direct DM search with ultralow noise ionization detectors CoGeNT Ge target p-type point contact (PPC) Germanium detector (HPGe) to investigate low mc low threshold small target mass (475g) (330 m.w.e., part of Chicago s Tunnel And Reservoir Plan) 4 Klaus Eitel BOSEN workshop 29 August 3 September 2010 p-type point contact (PPC) Germanium detector (HPGe) JCAP09(2007)009

5 direct DM search with ultralow noise ionization detectors CoGeNT (i) a low-bg NaI[Tl] anti-compton veto, (ii) 5 cm of low-background lead, (iii) 15 cm of standard lead, (iv) 0.5 cm of borated neutron absorber, (v) a >99:9% efficient muon veto, (vi) 30 cm of polyethylene, (vii) a low-effic. large-area external µ veto exposure: 8.4kg.d mc=8gev, s SI =10-4 pb mc=6gev, s SI =2x10-3 pb mc=4gev, s SI =10-2 pb 5 Klaus Eitel BOSEN workshop 29 August 3 September 2010 PRL 101, (2008)

6 direct DM search CoGeNT(2010) light WIMP signal? 440g (2100mwe) with rise time discrimination mc=7(10)gev, s SI =10-4 pb fast (t=0.22µs) slow (t=1.53µs) C. Aalseth etal., arxiv: v1 6 Klaus Eitel BOSEN workshop 29 August 3 September 2010

7 direct DM search CoGeNT(2010) light WIMP signal? In view of its apparent agreement with existing WIMP models, a claim and a glimmer of dark matter detection in two other experiments, it is tempting to consider a cosmological origin. Prudence and past experience prompt us to continue work to exhaust less exotic possibilities. We extend an invitation to other researchers in this field to proceed with the same caution.... C. Aalseth etal., arxiv: v1 7 Klaus Eitel BOSEN workshop 29 August 3 September 2010

8 direct DM search detection schemes HDMS CoGeNT COUPP Picasso Ge, CF 3 I, C 4 F 10 10% energy Ionization WIMP via elastic scattering off nuclei Ge, Si Edelweiss, CDMS 8 WArP, ArDM liquid Xe/Ar Zeplin-3, LUX, Xenon-10/100 NaI, liqu.xe Target Light 1% energy fastest no surface effects DAMA, Libra, Zeplin-1, XMASS, KIMS, ANAIS Klaus Eitel BOSEN workshop 29 August 3 September 2010 WIMP Heat 100% energy slowest cryogenics CaWO 4, BGO Al 2 O 3, LiF CRESST-1 CRESST-2

9 direct DM search using cryo-crystals measuring principle: c scattering with energy deposit E R leads to DT which can be read out via thermometer detector with small V. C V needed Thermometer heat Electrodes (charge collection ) 9 c ionization parameters for Ge bolometer: E = 3V/cm T op = 20mK m = 300g (d=20mm; r=35mm) VC V ~ T op G ~ 5nW/K thermal link to heat bath Klaus Eitel BOSEN workshop 29 August 3 September 2010 Thermometer

10 direct DM search n/g-discrimination PRD 71, (2005) 73 Ge(n,n g) 68.8 kev 13.3 kev calibration of a 320g Ge bolometer with 252 Cf n/g discrimination > 99.9% for E r >15 kev Recoil threshold 20 kev Ionization threshold 3.7 kev 10 Klaus Eitel BOSEN workshop 29 August 3 September 2010

11 direct DM search LSM 11 Klaus Eitel BOSEN workshop 29 August 3 September 2010

12 direct DM search LSM Polyethelene shield Pb shield cryostat Muon Veto Neutron counter µ veto system A=100m 2 in 42 modules 2009/2010: 12 Ge bolometers running 12 Klaus Eitel BOSEN workshop 29 August 3 September 2010

13 direct DM search Soudan Soudan Mine, Minnesota features: 30 detectors installed in 5 towers 4.75kg Ge & 1.1kg Si det s data taking since 10/2006 (>1000kg.d raw data) 1. data published in 2008 for 121.3kg.d eff. exposure (arxiv: v2 PRL.102:011301,2009) 13 Klaus Eitel BOSEN workshop 29 August 3 September 2010

14 direct DM search n/g-discrimination and surface events PRD71, (2005) surface bg source: leakage from the g to the nuclear recoil band Cu few mm 5 mm g 46 kev a 206 Pb e - 10keV - 100keV - 1MeV NO ionisation Al 70nm amge 70nm ~50 nm 210 Pb 350 nm e - 61 kev max 210 Bi 22 yr g 46.5 kev (4%) 210 Po 206 Pb a Ge 2cm 20 mm 700 mm e MeV max 3 mm 100 kev 14 Klaus Eitel BOSEN workshop 29 August 3 September MeV

15 Z (cm) direct DM search surface events suppression via ionisation signal (Edelweiss-II): interleaved electrodes (width: 200µm; gap 2mm) a electrodes: U=+2V b electrodes: U=+1V a&b nearsurface event guard g : U=+1V a&c bulk event a,b&c event in low-field area electron trajectories hole trajectories guard h : U=-1V c electrodes:u=-2v d electrodes: U=-1V Radius (cm) arxiv Phys.Lett. B681 (2009) Klaus Eitel BOSEN workshop 29 August 3 September 2010

16 ionisation yield direct DM search surface events suppression via phonon signal (CDMS): effective and fast phonon read-out (t rise ~5µs) surface evts fast evts g s/electrons surface evts neutrons timing parameter [µs] RoI 16 Klaus Eitel BOSEN workshop 29 August 3 September 2010

17 direct DM search results w/ Ge bolos arxiv CDMS 1 event survives 0.23 bg expected 2 events survive 0.9 bg expected Edelweiss Science 26March2010:1619 arxiv (612 kg.d raw data ) PLB687 (2010) 294 (data 4/2009-9/2009) (194.4 kg.d eff. Exposure, 10keV thresh.) (144 kg.d eff. Exposure, 20keV thresh.) s(si)< cm 2 for m(c)= 70 GeV s(si)< cm 2 for m(c)= 80 GeV 17 Klaus Eitel BOSEN workshop 29 August 3 September 2010

18 CDMS next steps Soudan (funded) March 19, 2009: warm up to install and commission first SuperCDMS detectors Fabrication of detectors for SuperCDMS Soudan (~13 kg Ge) project underway ~8000 kg.d SuperCDMS SNOLAB (PASAG endorsed) Project proposal in 2011 for ~100 kg Ge experiment GEODM (NSF DUSEL S4 funded) GErmanium Observatory for Dark Matter (1.5 tons Ge) proposed for Dusel SuperCDMS detector Ø=7.5cm,d=1cm (230g) Ø=7.5cm,d=2.5cm (600g) new izip design 18 Klaus Eitel BOSEN workshop 29 August 3 September 2010

19 Edelweiss next steps >300kg.d data taken & prelim. analysed Doubling/Quadrupling the fiducial mass: ID400 => FID400 => FID800 before selection FID400 >300g FID800 >600g ID400 (160g) After fiducial selection Goals: FIDs g program, doubling of accum. exp. every year kg.d exposure 2013 >3000 kg.d FID Pb 4 running since July Klaus Eitel BOSEN workshop 29 August 3 September 2010

20 direct DM search scintillating bolos CRESST-2 at LNGS 33 crystals installed Light detector W sensor 300g scintillaing CaWO 4 crystal Light reflector (scintillating) W sensor Light detector: Ø=40 mm silicon on sapphire wafer. Tungsten thermometer with attached aluminum phonon collectors and thermal link. Phonon detector: 300 g cylindrical CaWO 4 crystal. Evaporated tungsten thermometer with attached heater. 20 Klaus Eitel BOSEN workshop 29 August 3 September 2010

21 direct DM search scintillating bolos CRESST-2 at LNGS 3 target nuclei within detector assuming σ A 2 3 quenching factors for different nuclei β+γ α O W 21 Klaus Eitel BOSEN workshop 29 August 3 September 2010

22 direct DM search scintillating bolos CRESST-2 at LNGS 2009/2010 data from 9 CaWO 4 detectors (~400 kg.d; preliminary) 32 events in O-band γ + β band background estimate (mainly a): 8.7 ± 1.4 α band O-recoil-band W-recoil-band leaving space for a light WIMP m about 15 GeV or less σ about a few times 10-5 pb (W. Seidel, CRESST, idm2010) Pb α clamp not scint. 210 Po 206 Pb (104 kev) + α (5.4 MeV) crystal Pb α 22 Klaus Eitel BOSEN workshop 29 August 3 September 2010

23 direct DM search results 23 Klaus Eitel BOSEN workshop 29 August 3 September 2010

24 direct DM search scalar interaction? Light neutralinos?? 24 Klaus Eitel BOSEN workshop 29 August 3 September 2010

25 direct DM search hints for light c? T. Schwetz, IDM2010 light neutralinos? -- hard to reconcile compiling exptl. data 25 Klaus Eitel BOSEN workshop 29 August 3 September 2010

26 direct DM search hints for light c? 5x x x x10-42 cm 2 3x10-42 light neutralino within MSSM tension from B tn, B Dtn, F t+t-, t bh +, with CoGeNT&DAMA would need non-mssm DM Kulik, Pierce, Zurek, arxiv Klaus Eitel BOSEN workshop 29 August 3 September 2010

27 direct DM search elastic spin-dependent scattering? a p =1, a n =0 a p =0, a n =1 90% C.L. 90% C.L. Kopp, Schwetz, Zupan, arxiv Klaus Eitel BOSEN workshop 29 August 3 September 2010

28 direct DM search idm? Tucker-Smith, Weiner, hep-ph/ inelastic scattering must be favoured over elastic scattering could be naturally explained via dark gauge forces ( Bjorken) 28 Klaus Eitel BOSEN workshop 29 August 3 September 2010

29 direct DM search idm? DAMA excluded by CRESST 29 Klaus Eitel BOSEN workshop 29 August 3 September 2010

30 indirect DM search e+/(e+ e-) excess can be explained by nearby astrophysical sources space for DM signal? 30 Klaus Eitel BOSEN workshop 29 August 3 September 2010

31 indirect DM search (high-e solar n s) IceCube, PRL102,201302(2009) 31 Klaus Eitel BOSEN workshop 29 August 3 September 2010

32 future: increase target mass ~ Klaus Eitel BOSEN workshop 29 August 3 September 2010

33 future: EURECA EURECA goal: beyond pb, 500 kg to 1 tonne cryogenic experiment, multi-target Generation 2 project with major efforts in background control, detector development, infrastructure Joint European collaboration of teams from EDELWEISS, CRESST, ROSEBUD, CERN, +others Part of ASPERA European Roadmap Preferred site: m 2 ULISSE extension of present LSM (4 m/m 2 /d), to be excavated in Collaboration agreement with SuperCDMS & GeoDM for common studies MoU between EURECA, SuperCDMS and GEODM collaborations: Sep Klaus Eitel BOSEN workshop 29 August 3 September 2010

34 future: XENON1T & DARWIN XENON1T : construction 2011 start of measurements 2013 DARWIN: DARk matter WImp search with Noble liquids R&D and design study for next-generation noble liquid facility in Europe first ASPERA (AStroParticle ERAnet) in 2009 focus: coordinate existing European activities in liquid argon and xenon towards the construction of a multi ton DM facility physics goal: probe s(si) well below cm 2 many more projects worldwide!! 34 Klaus Eitel BOSEN workshop 29 August 3 September 2010

35 outlook New projects Xenon1t, EURECA, SNOLAB, Kamioka, AMS-02, Planck, Gravitational lensing, LHC But lessons learned: Be careful with data interpretation!!! personal: stay conservative, but open-minded Interaction between different communities needed, e.g. Astroparticle, astronomy, cosmology, collider, fixed-target, SUSY, theory BSM Klaus Eitel BOSEN workshop 29 August 3 September 2010