Search for Low Energy Events with CUORE-0 and CUORE

Transcription

1 Search for Low Energy Events with CUORE-0 and CUORE Kyungeun E. Lim (on behalf of the CUORE collaboration) Oct , APS Division of Nuclear Physics meeting, Santa Fe, NM

2 The CUORE Experiment CUORE is a cryogenic detector consisting of 988 TeO bolometers Primarily search for 0νββ decay Located at LNGS in Italy Plates: 300 K 40 K 4K In the final stages of construction, data-taking will begin in early 016 With 5 years of data accumulation, 0νββ 130 T1 ( Te) > y (90% C.L.) mββ < mev Also suitable for Dark Matter Search Kyungeun E. Lim (Yale University) 600 mk 50 mk mk Top Lead Shield Side Lead Shield Detector Towers (19) Bo om Lead Shield

3 WIMP Direct Detection Search ] -1 day -1 kg -1 r Differential Rate [evts kev GeV WIMP Xe Te Ge Ar Na O will be updated Recoil Energy [kev ] r WIMP Expectations 1 evt/kg/yr 1 evt/ton/yr CMSSM: Trotta et al. CMSSM + LHC: Buchmuller et al. Summary: Exponentially Falling Tiny Rates Large total mass Stable detector operation Low energy threshold Very low background Kyungeun E. Lim (Yale University) 3

4 WIMP Search with CUORE Total target mass of 741 kg Stable detector operation expected with pulse tube and dilution refrigerators Bolometer offers low energy threshold and good energy resolution Quenching factor ~ 1 benefits detection of nuclear recoil events First dark matter search with Te Kyungeun E. Lim (Yale University) 4

5 WIMP Search with CUORE Total target mass of 741 kg Stable detector operation expected with pulse tube and dilution refrigerators Bolometer offers low energy threshold and good energy resolution Quenching factor ~ 1 benefits detection of nuclear recoil events First dark matter search with Te Kyungeun E. Lim (Yale University) 5

6 Energy Threshold ADC counts Continuous Data Acquisition provides access to the low energy events Optimal Filter can identify low energy events 3 kev signal sample index Raw Pulse Optimal Filtered Pulse Efficiency 1 0 Energy [kev] Kyungeun E. Lim (Yale University) JINST 6 (011) P0007 Detection Efficiency 0νββ trigger Dark matter trigger

7 Energy Resolution 30 kev peak shows as low as 0.5 kev FWHM resolution Provides possibility of spectral background study at the dark matter region of interest Events / ( 0.5 kev ) Te X-ray CUORE Preliminary Energy (kev) Kyungeun E. Lim (Yale University) 7

8 Nuclear Recoil Quenching Using surface alpha events, it is possible to measure nuclear quenching of recoiling nuclei from Po, 18 Po, Rn decays Given 3 that Single the quenching crystal of phonon detector Po is expected CUORE-0 to be 1, the largest deviation Double from crystal 1 measured coincidences by 06 Preliminary Pb was integrated as uncertainty on the nuclear recoil energy scale. dn/de [cts/kev] Rn 18 Po Energy [kev] Kyungeun E. Lim (Yale University) 8

9 Nuclear Recoil Quenching Using surface alpha events, it is possible to measure nuclear quenching of recoiling nuclei from Po, 18 Po, Rn decays Nuclear quenching factor of phonon detector is expected to be 1 The largest deviation from 1 measured by 06 Pb was integrated as uncertainty on the nuclear recoil energy scale dn/de [cts/kev] 3 CUORE-0 Preliminary dn/de [cts/5kev] Pb CUORE-0 α Preliminary Double crystal coincidence (Energy Sum is Po Q-Value) Energy [kev] Kyungeun E. Lim (Yale University) Energy [kev] 9

10 Nuclear Recoil Quenching Using surface alpha events, it is possible to measure nuclear quenching of recoiling nuclei from Po, 18 Po, Rn decays Nuclear quenching factor of phonon detector is expected to be 1 The largest deviation from 1 measured by 06 Pb was integrated as uncertainty on the nuclear recoil energy scale dn/de [cts/kev] 3 CUORE-0 Preliminary dn/de dn/de [cts/5kev] Pb CUORE-0 Preliminary Double crystal coincidence (Energy Sum is Po Q-Value) Energy [kev] Kyungeun E. Lim (Yale University) Energy 180[keV] 00 Energy [kev]

11 CUORE Sensitivity ] -39 cross section per nucleon [cm DAMA DAMA CoGeNT no channeling channeling CRESST CUORE sensitivity -43 WIMP mass [GeV/c ] 3 JCAP 01 (013) 038 CUORE is expected to test the DAMA WIMP observation claim with 5 years of data accumulation Kyungeun E. Lim (Yale University) 11

12 Summary CUORE, a competitive 0νββ decay search using 741 kg of TeO crystals, is also suitable for low energy event searches Low energy threshold and excellent energy resolution demonstrated by crystal validation measurements Nuclear recoil quenching using CUORE-0, the predecessor of CUORE, has been measured using surface alpha events Annual modulation analysis of CUORE-0 is on-going and will report dark matter results using Te as a target material for the first time soon CUORE is expected to probe the DAMA WIMP observation region with 5 years of data-taking CUPID, beyond CUORE using particle discrimination to further suppress the background will be a competitive dark matter search Kyungeun E. Lim (Yale University) 1

13 CUORE Collaboration (Oct., LNGS) Kyungeun E. Lim (Yale University) 13