Direct Detection Laura Baudis, UZH Jocelyn Monroe, RHUL

Outline 1) Scientific Context 2) Community Input: 5-10 year Horizon for Direct Detection in Europe 3) APPEC GA Considerations for Discussion

Financial Context: bottom line in SAC Report to APPEC GA (2014): funding: 9ME/yr currently, ~12ME/yr requested, 2017-21: 16-20 ME/yr for G3 experiment(s) construction effort: currently 450-500 scientists, 60-80 engineers

Jocelyn Monroe April 6, 2016 / p. 1 of Cosmology

Dark Matter is ~30% of the energy density of the universe.

Jocelyn Monroe April 6, 2016 / p. 2 Searches for Dark Matter χ χ

Indirect Detection ? e-,ν,γ e+,p,D Collider Production jet

p p

χ χ

Direct Detection χ χ

N N’ Jocelyn Monroe April 6, 2016 / p. 3 Model Space

Wide range of parameters! Direct detection searches generally optimised for WIMP sensitivity...

Baer et al., arXiv:1407.0017 Jocelyn Monroe April 6, 2016 / p. 4 Model Space

Wide range of parameters! Direct detection searches generally optimised for WIMP sensitivity...

Baer et al., arXiv:1407.0017 Jocelyn Monroe April 6, 2016 / p. 4 Model Space

Wide range of parameters! Direct detection searches generally optimised for WIMP sensitivity...

but starting to look for axions too!

axion model space dark matter = axions

Baer et al., arXiv:1407.0017 Jocelyn Monroe April 6, 2016 / p. 4 The Low-Background Frontier: Prospects

1 event/ kg/day

1 event/ 100kg/day

1 event/ 100 kg/ 100 days

so far: ~3 years / order of magnitude

Jocelyn Monroe April 6, 2016 / p. 5 The Low-Background Frontier: Prospects

Low Mass, Large σ 1 event/ kg/day

Canonical MSSM Mass, 1 event/ 100kg/day σ > Neutrino Bound

1 event/ 100 kg/ High Mass, Tiny σ 100 days or Large # Events

so far: ~3 years / order of magnitude

Jocelyn Monroe April 6, 2016 / p. 5 Prospects: Near Term to 10-Year Horizon*

CRESST +EDELWEISS =EURECA annual modulation DAMIC + R&D efforts DEAP3600 XENON-1T LZ XENON-nT + others DarkSide+ArDM=ARGO DARWIN

R&D for direction sensitivity

*=for projects with funding from, or planned for Europe Jocelyn Monroe April 6, 2016 / p. 5 Low Mass, EDELWEISS (thanks to J. Gascon) Large σ EDELWEISS!

• Largest operating cryogenic Ge array (20 kg) for Direct DM search • Latest results: arXiv:1603.05120

• 2017 goal @ LSM: optimizing sensitivity to 1-10 GeV WIMPs

• Beyond: completing the exploration of the low-WIMP CRESST 2012! mass region with a ~100 kg

array of EDELWEISS detectors EDELWEISS in would require the environment SuperCDMS -EURECA projected for EURECA/ SuperCDMS

Jocelyn Monroe April 6, 2016 / p. 6 Low Mass, CRESST (thanks to F. Petricca) Large σ



                

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3  (  + !  !#  $ 4   ##     1  8& # Jocelyn Monroe  April 6, 2016 / p. 7 Low Mass, EURECA (thanks to K. Eitel) Large σ

EURECA

¾ accomplish low mass goals of EDELWEISS-III and CRESST-III phase 1 by 2017-2018

¾ common cryogenic infrastructure with SuperCDMS in SNOLAB by 2019

¾ contribute detectors SuperCDMS@SNOLAB and tower integration

¾ CUTE project Queen´s test facility at SNOLAB by 2017 to test tower integration & bgd suppression

SCDMS design KIT mockup of tower

20

Jocelyn Monroe April 6, 2016 / p. 8 Low Mass, Annual Modulation Searches (thanks to J. Villar) Large σ DAMA (LNGS), DM-Ice (S. Pole, Boulby), ANAIS (Canfranc), ++

Jocelyn Monroe April 6, 2016 / p. 9 MSSM Mass, XENON-100 (thanks to L. Baudis) σ > ν bound

• Ultra-low background and design sensitivity achieved • Background: ~ 5 x 10-3 events/(kg d keV) • No evidence for WIMP dark matter • Upper limits on SI, SD WIMP-nucleon cross sections (PRL 109, PRL 111) • Axion, ALPS searches (Phys. Rev. D 90, 062009 (2014) • Annual modulation search excludes leptophilic DM explanation of DAMA/LIBRA (Science 349, 2015)

SD-neutron SD-proton

Jocelyn Monroe April 6, 2016 / p. 10 MSSM Mass, XENON-1T / Xenon-nT (thanks to E. Aprile)

σ > ν bound arXiv:1512.07501, continues from XENON-10, XENON-100 at LNGS accepted in JCAP

XENON-1T: 3.5 Tonnes LXe (1T fiducial). TPC installed Nov. 2015, 1st physics run: summer 2016. Sensitivity to 1E-47 cm2 in 2 Tonne-years.

XENON-nT: upgrade to 7T LXe (total), using same infrastructure + new TPC, inner cryostat. From 2018.

LZ: follow-on to LUX at SURF, 7T LXe (total). Passed CD-1/3a in 2015. Sensitivity to 2E-48 cm2. Jocelyn Monroe April 6, 2016 / p. 11 MSSM Mass, DarkSide-50 (thanks to G. Fiorini) σ > ν bound

• LArTPC (50 kg active, 150kg total) 38 3” PMTs at LNGS • Liquid scintillator veto (30 tons) 110 PMTs • Water veto (1 ktons) 80 PMTs

Demonstrated: • β/γ rejection capability better than 1÷107 with atmospheric • high-performance vetoing scheme and 39Ar suppression in underground argon by factor over 1,000

Zero background operation: ✦ 1,422 kg×d AAr (published) ✦ 2,616 kg×d UAr (published) ✦ 8,000 kg×d UAr (analysis ongoing)

Jocelyn Monroe April 6, 2016 / p. 12 (thanks to A. Rubbia) MSSM Mass, ArDM-1t σ > ν bound • Ton-scale LAr TPC at Canfranc underground Laboratory (LSC, Spain) @ 2500 m.w.e. • 850 kg acve mass, 24 8” PMTs, low background • 1st 6-month run in single phase in 2015: to explore features of LAr for DM@ton-scale • Now preparing double phase Run II — scheduled for 2016 • 2017 and beyond: (a) accumulate stascs + light yield/hardware upgrades (b) depleted argon studies with sensivity down to 10-5 together with DarkSide. Demonstraon at the ton-scale is a necessary step towards 10-tons and beyond. Low BG studies Pulse shape discriminaon

Jocelyn Monroe April 6, 2016 / p. 13 MSSM Mass, DEAP-3600 σ > ν bound Single Phase liquid Argon detector, a la neutrino detectors like SNO: self-shielding of target, detect scintillation only with 4π PMT coverage

DEAP-3600: 3.6 T LAr at SNOLAB. Project <0.6 background in 3 T-years, 1E-46 cm2 reach. Commissioning since 2015, physics start Spring 2016. Single phase: R&D towards the kTonne scale in dark matter detection

no electric fields = scale to large masses (a la νs) 1) no pile-up from ms-scale electron drift in TPC 2) no recombination in E field Trigger rate vs. me but background discrimination from scintillation only! (shows veto fill)

Jocelyn Monroe April 6, 2016 / p. 12 (thanks to C. Galbiati) High Mass, ARGO Large # Events σ < ν bound An Integrated Program for the Ultimate DM Search with 39Ar-suppressed Argon TPCs

• Ultimate search requires 1,000 T-yr background-free exposure

• 39Ar-suppressed Ar TPC can deliver due to β/γ suppression

• Key enabling technologies R&D funded and ongoing: • Cryogenic SiPMs • Urania: 100 kg/d procurement of UAr • Aria: active isotopic separation of 39Ar via cryogenic distillation

DarkSide-50 (now) DarkSide-20k (2020?) Argo (2025?) 100 T-yr background-free search • 1,000 T-yr background-free ArDM-1t (now) search to reach the “neutrino floor” • precision low-energy measurements

Jocelyn Monroe April 6, 2016 / p. 15 (thanks to L. Baudis) High Mass, DARWIN Large # Events σ < ν bound JCAP10 (2015) 016 Ulmate LXe TPC at LGNS.  50 t (40 t) Lxe in total (in the TPC)  ~103 photosensors  2.6 m dri length, 2.6 m diameter TPC  Background: dominated by neutrinos  WIMP spectroscopy, search + non-WIMP science: axion / ALP search, solar neutrinos, supernova neutrinos, sterile neutrinos, coherent neutrino – nucleus scaering, 0ν2β decay of 136Xe.

Update: Newstead et al., PRD D 88, 076011 (2013) Jocelyn Monroe Update: Newstead et al., PRD D 88, 076011April 6, (2013) 2016 / p. 16 (thanks to I. Irastorza) WIMPs are IAXO not the only possibility! IAXO builds on decade of European axion helioscopes: CAST at CERN. complementary reach with cavity searches, Timeline: + >10x gain in QCD axion reach over current results – Conceptual Design 2013 – Letter of Intent to SPSC 2014, received positive recommendation to develop TDR – TDR design and prototyping ongoing: – IAXO-D0: low background x-ray detectors prototypes, HB – IAXO-X0 : x-ray optics hint – IAXO-T0: superconducting magnet coil – Funding path for TDR (almost) clear.

•Large toroidal 8-coil magnet L = ~20 m •8 bores: 600 mm diameter each •8 x-ray telescopes •Rotating platform NDW>1 Axion

Discussion for funding path for IAXO underway – includes scenarios with IAXO in sites alternative to CERN – Critical moment for the project, with first dedicated funding Enhanced axion helioscope: JCAP 1106:013,2011 – support from APPEC roadmap very important for the project Jocelyn Monroe April 6, 2016 / p. 17 dark matter Directional Detection identification, σ > ν bound R&D towards DM recoil track direction to identify a signal with the galactic halo arXiv:1602.03781

DMTPC n calibration data, DMTPCMC fit templaten calibration data, 50 keVr charge data, nuclear recoil150 keVr

anode grid DRIFT: 1m3 MWPC, in Boulby since 2001

Voltage DMTPC: optical (CCD) and charge readout 3 of CF4; commissioning 1m module.

MIMAC: micromegas, in LSM. Low E focus.

time (s) R&D: fine-grained emulsions ++ + projects outside Europe

CYGNUS: global coordination towards a physics-scale directional experiment. DMTPC

Directionality gains up to 10x in sensitivity in the presence of backgrounds (relative to 1D). and there is no neutrino bound for directional detectors. Phys.ReV.D90 (2014) 055018

Jocelyn Monroe April 6, 2016 / p. 18 APPEC GA Considerations for Discussion Europe should: 1) support and closely follow the development/results of the “G2” experiments directly searching for WIMP DM in 1 GeV-10 TeV/c2 range.

2) APPEC should appoint a scientific and technical committee to work with the European DM community to recommend the technologies for noble-liquid “G3” direct detection experiments in synergy/ complementarity with similar detectors in other regions of the world

3) support the participation of European groups in an international large “G3” bolometric detector (e.g. EURECA).

4) support R&D and technology to build a directional detector.

5) support non-WIMP searches and R&D activities (e.g. axions: ADMX, IAXO; ALPS, hidden sector particles: SHIP, ++)

6) encourage the synergy with indirect searches (e.g. CTA, KM3NET)

Jocelyn Monroe April 6, 2016 / p. 19 My Comments Europe should: 1) increase the resources in this area. Fraction of the energy density of the universe: 30%. Fraction of astroparticle funding in Europe: <10%. Fraction of European astroparticle physicists working in this area: 25%*

2) Europe has some of the best facilities in the world for this science, with a decade of world-leading results. Should site “G3” project(s) here.

3) Dark matter experiment costs are small relative to telescopes, long baseline neutrino oscillations, space missions, etc. A coherent strategy to maximize discovery potential could be to have strong participation in searches at range of WIMP mass scales (low, mid, high). (‘coherent’ doesn’t by definition mean ‘only one’ experiment is funded.)

4) maximize discovery potential through increased participation in searches for other dark matter particle candidates (IAXO, ALPS, SHIP)

*=includes people working on multiple projects, with overlap in other areas Jocelyn Monroe April 6, 2016 / p. 20