[PPT] - Pr Probing new physics via via extr trem emely ely rar are e PowerPoint Presentation

SLIDE 1

Pr Probing new physics via via extr trem emely ely rar are e dec decay sear earch h wi with h GER ERDA A and nd LEGEN END

Yoann KERMAÏDIC

LPSC seminar Grenoble

23 January 2020

SLIDE 2

Cru Crucial open issu ssues s in part rticle physi sics

! = #$ − #$

&

#' = (. *++ ± -. -(. ×*-0*- [Planck, 2018] (. **? ± -. *-- ×*-0*- [Cooke, 2018]

Baryonic asymmetry

f the Universe

Number of photons (light) Number of baryons / antibaryons (matter) / (antimatter)

Among many theoretical BSM models: the leptogenesis!?

[Cooke, 2014] [Planck, 2018]

Cosmic Microwave Background Element abundance of the Universe 23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 2

SLIDE 3

Cru Crucial open issu ssues s in part rticle physi sics

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 3

Is the neutrino its own antiparticle? Only neutral elementary fermion

! = #$ − #$

&

#' = (. *++ ± -. -(. ×*-0*- [Planck, 2018] (. **? ± -. *-- ×*-0*- [Cooke, 2018]

Baryonic asymmetry

f the Universe

Number of photons (light) Number of baryons / antibaryons (matter) / (antimatter)

Among many theoretical BSM models: the leptogenesis!?

SLIDE 4

Cru Crucial open issu ssues s in part rticle physi sics

Non-zero but tiny neutrino masses See-saw mechanism?

requires neutrinos to be Majorana - Lepton Number is violated in general
new mass term in the Lagrangian explaining the smallness of masses
provides a mechanism for effective leptogenesis

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 4

Is the neutrino its own antiparticle? Only neutral elementary fermion

! = #$ − #$

&

#' = (. *++ ± -. -(. ×*-0*- [Planck, 2018] (. **? ± -. *-- ×*-0*- [Cooke, 2018]

Baryonic asymmetry

f the Universe

Number of photons (light) Number of baryons / antibaryons (matter) / (antimatter)

Among many theoretical BSM models: the leptogenesis!?

SLIDE 5

Cru Crucial open issu ssues s in part rticle physi sics

Non-zero but tiny neutrino masses See-saw mechanism?

requires neutrinos to be Majorana - Lepton Number is violated in general
new mass term in the Lagrangian explaining the smallness of masses
provides a mechanism for effective leptogenesis

HOW TO RELATE THIS TO 76Ge?

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 5

Is the neutrino its own antiparticle? Only neutral elementary fermion

! = #$ − #$

&

#' = (. *++ ± -. -(. ×*-0*- [Planck, 2018] (. **? ± -. *-- ×*-0*- [Cooke, 2018]

Baryonic asymmetry

f the Universe

Number of photons (light) Number of baryons / antibaryons (matter) / (antimatter)

Among many theoretical BSM models: the leptogenesis!?

SLIDE 6

Tw Two neut neutrino nos do doubl uble e be beta dec decay - 2CDD

Such process:

ü energetically favored in some isotopes ( Ge

FG

, Se

IJ

, Mo

LMM

, Te

LOM

, Xe

LOG

, …) ü is predicted by the SM [Goppert-Mayer – 1935] ü is measured experimentally

SM particles

n

n n p p

Q0 Q0

RS RS

T U T U

(V,W) → (V,W+2) + 2Y0+ 2T & Ge

OJ FG

As

OO FG

Se

O\ FG

]]

26.3 h +×*-+* a

b (def) 2 h ]0 A= i(

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 6

SLIDE 7

Ne Neutrinoless d double b beta dec decay - 0CDD

n n p p

Q0 Q0 T

RS RS

Such process:

ü violates the Lepton Number by 2 units = New Physics! ü determines the nature of neutrinos: Majorana particle T = T & [Valle – 1982] ü gives information on the C mass via jkk (light neutrino exchange scenario)

♾ has never been observed so far

Ø High sensitivity due to the Avogadro number: ~10Jm Ge nuclei / kg

Light neutrino exchange SM particles Heavy neutrino exchange BSM particles n n p p

Qn Qn

RS

RS (V,W) → (V,W+2) + 2Y0 (V,W) → (V,W+2) + 2Y0

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 7

SLIDE 8

« Li Light neutri rino exchange »

Attractive: Minimal model without requiring new particles (mediator = active C)
Direct relationship with the cosmological neutrino mass sum and direct mass measurement
Rich complementarity in case of non-zero measurement in one of the channels
U = PMNS matrix

[NuFit 19’]

4

10

3

10

2

10

1

10

1 (eV)

lightest

m

3

10

2

10

1

10

1 (eV)

b b

m

paradigm: n 3 NO IO

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 8

p*/+

T 0* = rV

s t-T u-T +

v]]

+

vY

+

p*/+

T

experimentally probed half-life rV axial vector coupling cnst = 1.25(?) u-T nuclear matrix element (NME) wMx phase space factor jy electron mass Mass hierarchy not yet probed conclusively by

SLIDE 9

« Li Light neutri rino exchange »

Attractive: Minimal model without requiring new particles (mediator = active C)
Direct relationship with the cosmological neutrino mass sum and direct mass measurement
Rich complementarity in case of non-zero measurement in one of the channels
NB: Hubble constant “problem” shows some limitations

U = PMNS matrix [NuFit 19’]

4

10

3

10

2

10

1

10

1 (eV)

lightest

m

3

10

2

10

1

10

1 (eV)

b b

m

paradigm: n 3 NO IO 1

10

1 (eV) S

3

10

2

10

1

10

1 (eV)

b b

m

2

10

1

10

1 (eV)

b

m

3

10

2

10

1

10

1 (eV)

b b

m

Cosmo - direct: Planck min Planck ext KATRIN 5 yr

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 9

SLIDE 10

Co Cosmo smological de detour ur : : H0 0 « pr probl blem em »

z. .{!

[Planck, 1807.06209] [1907.04869]

H0 = Hubble constant in [km/s/Mpc], measuring how fast the Universe is expanding
Special workshop organized in July 2019 to review all the H0 measurements:

“ Tensions between the Early and the Late Universe”

all the slides at http://online.kitp.ucsb.edu/online/enervac-c19/

directly connected

to the previous plots

phenomenology

not 100% under control

models dependence

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 10

SLIDE 11

Attractive: Minimal model without requiring new particles (mediator = active C)
Direct relationship with the cosmological neutrino mass sum and direct mass measurement
Rich complementarity in case of non-zero measurement in one of the channels
« Li

Light neutri rino exchange »

U = PMNS matrix [NuFit 19’]

4

10

3

10

2

10

1

10

1 (eV)

lightest

m

3

10

2

10

1

10

1 (eV)

b b

m

paradigm: n 3 NO IO 1

10

1 (eV) S

3

10

2

10

1

10

1 (eV)

b b

m

Ge sensitivity: Gerda 2

10

1

10

1 (eV)

b

m

3

10

2

10

1

10

1 (eV)

b b

m

Cosmo - direct: Planck min Planck ext KATRIN 5 yr

ngoing [Science 19’]

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 11

SLIDE 12

« Li Light neutri rino exchange »

U = PMNS matrix [NuFit 19’]

Attractive: Minimal model without requiring new particles (mediator = active C)
Direct relationship with the cosmological neutrino mass sum and direct mass measurement
Rich complementarity in case of non-zero measurement in one of the channels
23/01/2020

Yoann Kermaïdic - LPSC seminar - Grenoble 12

ngoing [Science 19’]

SLIDE 13

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

0CDD dec

decay exper xperimen ental signa gnatur ure

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

high - energy resolution - low

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

2CDD continuum + peak at |kk
}

L/J Mx = ln 2 . ~ Ä . Å . ℇ . L ~É

Key points:
Avogadro number: Ñ

Ö

Efficiency [%] x exposure [kg.yr]: Å . ℇ
Energy resolution [keV]
BI = ~à

ℇ . âä [cts/(keV.kg.yr)]

Topology :
Signal = Single-Site Event (SSE)
Background ã = Multi-Site Event (MSE)

å/D = Surface Event

example : 76Ge }

L/J Mx = 10J\ yr

ℇ = 30 kg. yr 23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 13

SLIDE 14

Yoann Kermaïdic - LPSC seminar - Grenoble

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 93 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 100.0 keV b b n 2

0CDD dec

decay expe xperimental si sign gnature

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 95 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 30.0 keV b b n 2

high - energy resolution - low

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 119 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 3.0 keV b b n 2

example : 76Ge }

L/J Mx = 10J\ yr

ℇ = 30 kg. yr 23/01/2020 14

SLIDE 15

Yoann Kermaïdic - LPSC seminar - Grenoble

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 93 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 100.0 keV b b n 2

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 515 Bkg index : 6.0e-02 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 3.0 keV b b n 2

0CDD dec

decay expe xperimental si sign gnature

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 95 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 30.0 keV b b n 2

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 145 Bkg index : 6.0e-03 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 3.0 keV b b n 2

high - energy resolution - low low – background level - high

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 119 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 3.0 keV b b n 2

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 119 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 3.0 keV b b n 2

example : 76Ge }

L/J Mx = 10J\ yr

ℇ = 30 kg. yr 23/01/2020 15

SLIDE 16

Yoann Kermaïdic - LPSC seminar - Grenoble

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 93 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 100.0 keV b b n 2

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 515 Bkg index : 6.0e-02 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 3.0 keV b b n 2

0CDD dec

decay expe xperimental si sign gnature

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 95 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 30.0 keV b b n 2

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 145 Bkg index : 6.0e-03 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 3.0 keV b b n 2

high - energy resolution - low low – background level - high

500 1000 1500 2000 2500 3000 Energy [keV] 0.5 1 1.5 2 2.5 Counts [/keV.kg.yr]

b b n 2 b b n

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 119 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 3.0 keV b b n 2

1950 2000 2050 2100 2150 Energy [keV]

4

10

3

10

2

10

1

10

1 10 Counts (/keV.kg.yr)

Entries: 119 Bkg index : 6.0e-04 cts/(keV.kg.yr) : 1.0e+24 yr

n 1/2

T FWHM : 3.0 keV b b n 2

example : 76Ge }

L/J Mx = 10J\ yr

ℇ = 30 kg. yr

Two statistical notions scrutinized:

sensitivity for limit setting (90% C.L.)

« limit on the signal strength assuming no signal »

3ê discovery potential sensitivity

« minimal signal strength for which a discovery is expected with 3ê C.L. »

23/01/2020 16

see detailed discussion in: [1705.02996]

SLIDE 17

3

10

2

10

1

10

1 10

2

10

3

10 Exposure [ton-years]

24

10

25

10

26

10

27

10

28

10

29

10

30

10 DS [years] s 3

1/2

T

range

min b b

IO m Background free 0.1 counts/FWHM-t-y 1.0 count/FWHM-t-y 10 counts/FWHM-t-y

Ge (88% enr.)

76

Fig Figur ure e of mer erit it – di discover ery po poten ential

Defines the experimental design in terms of

exposure (mass et duration)
background goal (passive/active veto, detector design, analysis techniques)

example : « minimal signal strength for which a discovery is expected with 3ê C.L. »

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 17

see detailed discussion in: [1705.02996]

SLIDE 18

3

10

2

10

1

10

1 10

2

10

3

10 Exposure [ton-years]

24

10

25

10

26

10

27

10

28

10

29

10

30

10 DS [years] s 3

1/2

T

range

min b b

IO m Background free 0.1 counts/FWHM-t-y 1.0 count/FWHM-t-y 10 counts/FWHM-t-y

Ge (88% enr.)

76

Fig Figur ure e of mer erit it – di discover ery po poten ential

Defines the experimental design in terms of

exposure (mass et duration)
background goal (passive/active veto, detector design, analysis techniques)

example : « minimal signal strength for which a discovery is expected with 3ê C.L. »

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 18

GERDA MJD

LEGEND 200

LEGEND 1000

running/ running/ended ended .- kg kg p*/+

T > *-+( yr

yr mid mid-term term +-- kg kg p*/+

T > *-+i yr

yr long long-term term * ton ton p*/+

T > *-+í yr

yr

SLIDE 19

Un Under erground lab laboratories ies world ldwid ide

[arXiv:1801.00587]

Underground = passive background suppression for « free »
Isotopic activation suppression (neutron capture– e.g.

Ge

FG

+ î → Ge

FFï

→ As

FF

+ 2.7 MeV)

Large experimental infrastructure required (shielding, cryostat, instrumentation)
Size/depth/access compromise taken into account by the collaborations

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 19

SLIDE 20

Un Under erground lab laboratories ies world ldwid ide

[arXiv:1801.00587]

Underground = passive background suppression for « free »
Isotopic activation suppression (neutron capture– e.g.

Ge

FG

+ î → Ge

FFï

→ As

FF

+ 2.7 MeV)

Large experimental infrastructure required (shielding, cryostat, instrumentation)
Size/depth/access compromise taken into account by the collaborations

Gerda

LEGEND-200 CUORE CUPID-0 Majorana SuperNEMO CUPID-Mo SNO+ KamLAND-ZEN 23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 20

SLIDE 21

GERDA Collaboration meeting Zurich, Switzerland June 2019

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 21

ITEP Moscow Kurchatov Institute

http://www.mpi-hd.mpg.de/gerda/

INR Moscow

About 100 scientists from Europe

SLIDE 22

GERDA location @ @ LNGS

Large space available at LNGS + convenient access via highway clean room water tank

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 22

SLIDE 23

To Toward th the e bac ackground-fr free re regime

signal signature

Liquid Ar Pure water Optical fibers

DD decay signal: single energy deposition in a 1 mm3 volume

]]

C C

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 23

SLIDE 24

To Toward th the e bac ackground-fr free re regime

background mitigation

]]

C C

Liquid Ar Pure water ñ

Muon veto based on Cherenkov light and plastic scintillator DD decay signal: single energy deposition in a 1 mm3 volume

Optical fibers

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 24

SLIDE 25

To Toward th the e bac ackground-fr free re regime

background mitigation

Liquid Ar Pure water Optical fibers ñ

Muon veto based on Cherenkov light and plastic scintillator LAr veto based on Ar scintillation light read by fibers and PMT DD decay signal: single energy deposition in a 1 mm3 volume

'

]]

C C

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 25

SLIDE 26

To Toward th the e bac ackground-fr free re regime

background mitigation

' ' Liquid Ar Pure water Optical fibers ñ

Muon veto based on Cherenkov light and plastic scintillator LAr veto based on Ar scintillation light read by fibers and PMT Ge detector anti-coincidence DD decay signal: single energy deposition in a 1 mm3 volume

]]

C C

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 26

SLIDE 27

To Toward th the e bac ackground-fr free re regime

background mitigation

Muon veto based on Cherenkov light and plastic scintillator LAr veto based on Ar scintillation light read by fibers and PMT Ge detector anti-coincidence Pulse shape discrimination (PSD) for multi-site and surface å, D events DD decay signal: single energy deposition in a 1 mm3 volume

ó ' ' Liquid Ar Pure water Optical fibers ñ ' ]

]]

C C

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 27

SLIDE 28

GE GERDA Ph Phas ase II: Fr From conce cept to design

590 m3 ultra-pure water

plastic scintillator panels

muon veto

clean room

64 m3 LAr cryostat

coolant, shielding

wavelength shifting fibers with SiPM read-out

LAr veto instrumentation low-mass, low- activity electronics

Ge detector array low mass detector holder BEGe detector

Slide: L. Pandola – TAUP 2017 23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 28

SLIDE 29

Ge detect ctors pha phase I II

7 strings with 40 detectors:

3 natural semi-coaxial (7.6 kg)
7 enriched semi-coaxial (15.6 kg)
30 enriched BEGe (20.0 kg)

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 29

SLIDE 30

600 800 1000 1200 1400 1600 1800 2000 2200 2400 2600 FWHM (keV) 2 2.5 3 3.5 4

enriched coaxial enriched BEGe calibration data

b b

Q

GERDA 18-06

Energy (keV) 500 1000 1500 2000 2500 Counts / 5 keV

3

10

4

10

5

10

6

10

7

10

8

10

583 keV 763 keV 861 keV 2615 keV (SEP) 2104 keV (DEP) 1593 keV 727 keV 785 keV 893 keV 1079 keV 1513 keV 1621 keV

Tl-208 Bi-212

Ene Energy gy ca calibration

3 weak 228Th sources lowered every ~ week

3.6(1) keV FWHM 3.0(1) keV FWHM

2 years of calibrations! 23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 30

SLIDE 31

Ph Phas ase II physics cs da data mo model eling be before cu cuts

2

10

1

10

1 10

2

10

3

10

4

10 counts / 5 keV 25 keV ±

b b

Q yr × Enriched detectors - 60.2 kg Po

210

K

42

K

40

Tl

208

Bi

214

Bi

214

b b n 2

GERDA 19-07

1000 2000 3000 4000 5000 energy [keV]

2

10

1

10

1 10

2

10

3

10 counts / 5 keV

single detector two detectors [1909.02522]

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 31

Published data collection: from Dec. 2015 to April 2018 Blinding strategy: Hide events falling in |kk ± 25 keV into non-public files Data quality + muon veto applied Energy range above 39Ar spectrum (|k = 565 keV)

SLIDE 32

2

10

1

10

1 10

2

10

3

10

4

10 counts / 5 keV 25 keV ±

b b

Q yr × Enriched detectors - 60.2 kg Data Model Tl

208

Bi +

212

Pb

214

Bi +

214

Ac

228

b b n 2 K

40

K

42

Co

60

Po

210

GERDA 19-07

1000 2000 3000 4000 5000 energy [keV]

2

10

1

10

1 10

2

10

3

10 counts / 5 keV

Ph Phas ase II physics cs da data mo model eling be before cu cuts

single detector two detectors [1909.02522]

MaGe (Geant4) modelization

f GERDA

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 32

SLIDE 33

23/01/2020

2

10

1

10

1 10

2

10

3

10

4

10 counts / 5 keV 25 keV ±

b b

Q yr × Enriched detectors - 60.2 kg Data Model Tl

208

Bi +

212

Pb

214

Bi +

214

Ac

228

b b n 2 K

40

K

42

Co

60

Po

210

GERDA 19-07

1000 2000 3000 4000 5000 energy [keV]

2

10

1

10

1 10

2

10

3

10 counts / 5 keV

Ph Phas ase II physics cs da data mo model eling be before cu cuts

single detector two detectors [1909.02522]

MaGe (Geant4) modelization

f GERDA

Yoann Kermaïdic - LPSC seminar - Grenoble 33

Fine modelling of all individual parts Priors: Constrains from screening measurements Weakness: Fairly high degeneracy of some components

SLIDE 34

Ph Phas ase II physics cs da data mo model eling be before cu cuts

2

10

1

10

1 10

2

10

3

10

4

10 counts / 5 keV 25 keV ±

b b

Q yr × Enriched detectors - 60.2 kg Data Model Tl

208

Bi +

212

Pb

214

Bi +

214

Ac

228

b b n 2 K

40

K

42

Co

60

Po

210

GERDA 19-07

counts / 5 keV

1950 2000 2050 2100 2150 energy [keV]

2

10

1

10

1 10 counts / 2 keV

GERDA 19-09

28.1 kg yr

M1-enrCoax 1950 2000 2050 2100 2150 energy [keV]

2

10

1

10

1 10 counts / 2 keV

GERDA 19-09

32.1 kg yr

M1-enrBEGe

[1909.02522]

34

Main outcome: Flat background hypothesis in the region of interest is valid

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble

SLIDE 35

Pu Pulse shape discriminat ation

Signal-like Compton bkg-like Alpha bkg-like

BEGe cut parameter: A/E
Semi-coaxial cut parameter:

Artificial Neural network + rise time

' (208Tl DEP)

ã (511 keV) ã (511 keV)

ó '

ã

BEGe detector:

Slow pulses bkg-like

]

NB: 100 MHz / 10 ös long trace

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 35

Signal-like Compton bkg-like

208Tl DEP (1592 keV) used as a

proxy for Single-Site Events (SSE)

Multi-Site Events (MSE) cut set such

that 90% of 208Tl DEP events survive

Alphas and Betas cut thanks

to specific signal time profile

SLIDE 36

Counts / 3 keV

3

10

4

10

5

10

6

10

enriched coaxial all calibration events after MSE rejection (ANN)

GERDA 18-06

Energy (keV) 1200 1400 1600 1800 2000 2200 2400 2600 Survival fraction 0.2 0.4 0.6 0.8

PS PSD on calib alibratio tion data

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 36

Counts / 3 keV

3

10

4

10

5

10

6

10

enriched BEGe all calibration events after MSE rejection (A/E)

GERDA 18-06

Energy (keV) 1200 1400 1600 1800 2000 2200 2400 2600 Survival fraction 0.2 0.4 0.6 0.8

208Tl DEP (1592 keV) used as a

proxy for Single-Site Events (SSE)

Multi-Site Events (MSE) cut set such

that 90% of 208Tl DEP events survive

Alphas and Betas cut thanks

to specific signal time profile

Much better performance with

point contact BEGe detectors w.r.t. semi-coaxial detectors

A/E much simpler analysis

better control of the systematics BEGe Semi-coaxial

208Tl DEP 212Bi FEP 208Tl FEP 208Tl SEP 208Tl DEP 212Bi FEP 208Tl FEP 208Tl SEP

SLIDE 37

Ph Phas ase e II II ph physics da data re release at Nu18

[600-1300] keV - 2CDD decays produce single-site events -> No suppression
[1450-1530] keV - Strong suppression of 40K and 42K gamma lines (MSE)
[> 3000]

keV - Suppression of almost all å events (p+ contact) Data taking from Dec. 2015 to April 2018 – Science (2019)

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 37

SLIDE 38

Ene Energy gy sp spectrum af after unbl unblindi nding ng!

Background index:

z. i0+.(

õs.*×*-0s úùû/(üef † ü° † a¢)

Background index:

z. (0+.s

õ..s×*-0s úùû/(üef † ü° † a¢)

Date 2013 2014 2015 2016 2017 2018 2019 90% sensitivity (years)

1/2

T

26

10

Sensitivity for limit setting Limit (90% CL)

Phase I Phase II

GERDA 18-06

Median sensitivity for limit setting *. * × *-+( yr (90% CL) Science (2019)

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 38

SLIDE 39

yr ) × kg × Counts / ( keV

3

10

2

10

1

10

yr × enriched coaxial - 23.1 kg

GERDA 18-06

Energy (keV) 1950 2000 2050 2100 2150 yr ) × kg × Counts / ( keV

3

10

2

10

1

10

yr × enriched BEGe - 30.8 kg s 2 ±

b b

Q

Ene Energy gy sp spectrum af after unbl unblindi nding ng!

Date 2013 2014 2015 2016 2017 2018 2019 90% sensitivity (years)

1/2

T

26

10

Sensitivity for limit setting Limit (90% CL)

Phase I Phase II

GERDA 18-06

Median sensitivity for limit setting *. * × *-+( yr (90% CL) Science (2019)

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 39

}

L/J Mx = 1.1×10JG yr

jkk = 100 − 230 meV

SLIDE 40

Si Since las last t unblin lindin ing

Upgrade of the detector array + LAr veto (May 2018)

Increase the LAr veto fibers coverage
Installed cleaner cables
Added five ICPC 76Ge detectors [Y.K. et al] (2018) ~ +9 kg

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 40

new LAr veto new ICPC det. new ICPC string

NB: 3 continuous weeks underground with a team of 10 people

SLIDE 41

Si Since las last t unblin lindin ing

Upgrade of the detector array + LAr veto (May 2018)

Increase the LAr veto fibers coverage
Installed cleaner cables
Added five ICPC 76Ge detectors [Y.K. et al] (2018) ~ +9 kg

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 41

1000 2000 3000 4000 5000 Energy (keV) 1 10

2

10 Counts

enriched inverted coaxial detectors - 4.7 kg.yr prior active background supression after pulse shape discrimination (PSD) after liquid argon (LAr) and (PSD) 25 keV ±

b b

Q

1950 2000 2050 2100 2150 Energy (keV) 0.5 1 1.5 2 Counts

1125 keV

Zn

65 1481 keV

K

40 1525 keV

K

42 1724 keV

Bi

214 2615 keV

Tl

208 5307 keV

Po

210

GERDA preliminary

new LAr veto new ICPC det. new ICPC string

NB: 3 continuous weeks underground with a team of 10 people

SLIDE 42

Si Since las last t unblin lindin ing

Upgrade of the detector array + LAr veto (May 2018)

Increase the LAr veto fibers coverage
Installed cleaner cables
Added five ICPC 76Ge detectors [Y.K. et al] (2018) ~ +9 kg

Data taking ended in Dec. 2019

Goal in exposure 100 kg.yr reached
Next (final) unblinding session planned in March 2020!

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 42

Nu18 + upgrade

new LAr veto new ICPC det. new ICPC string

SLIDE 43

La Landscape af after TAUP UP 2019

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 43

T

L/J M§ sensitivity reported (not the lower limit)

jkk is mainly estimated from the lower T

L/J M§ limit except for Gerda

Nuclear Matrix Elements result in clear different goals for T

L/J M§ depending on the isotope

Inverted hierarchy jkk lower value is 20 meV

SLIDE 44

3

10

2

10

1

10

1 10

2

10

3

10 Exposure [ton-years]

24

10

25

10

26

10

27

10

28

10

29

10

30

10 DS [years] s 3

1/2

T

range

min b b

IO m Background free 0.1 counts/FWHM-t-y 1.0 count/FWHM-t-y 10 counts/FWHM-t-y

Ge (88% enr.)

76

Sc Scaling-up up / getting ng clea eaner ner!

Defines the experimental design in terms of

exposure (mass et duration)
background goal (passive/active veto, detector design, analysis techniques)

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 44

GERDA MJD

LEGEND 200

LEGEND 1000

running/ running/ended ended .- kg kg p*/+

T > *-+( yr

yr mid mid-term term +-- kg kg p*/+

T > *-+i yr

yr long long-term term * ton ton p*/+

T > *-+í yr

yr

?

SLIDE 45

Aft After er GE GERDA an and MAJ

AJORANA:

Legend collaboration:

47 institutions, ~240 scientists
GERDA / MAJORANA / external contributors

Staged approach to reach *-+í a¢ sensitivity:

LEGEND-200

→ *-+i a¢ after 5 years

LEGEND-1000 > *-+í a¢ (hosting lab under investigation)

LEGEND-200 phase:

Up to 200 kg of 76Ge
Modification of existing GERDA

infrastructure at LNGS

Improved background index
Data start in 2021
Most of funding secured
NEWS:

First six enriched ICPC L200 detectors produced + first Majorana det. ready

LEGEND Collaboration meeting, Seattle, Washington, US December 2019

Large Enriched Germanium Experiment for Neutrinoless ]] Decay 23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 45

SLIDE 46

LE LEGEND-200 200 Ba Backg kground Reduction

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 46

Improved radiopurity levels (cables (x7), electro-formed Cu, PTFE, ...)
Increased detector mass (≥x2) leads to proportional reduction from near-by parts
Higher purity LAr: increased scintillation light yield and attenuation length
Improved scintillation light readout (x2 shown in test stand)
Reduction of electronic noise leads to improved PSD
Increase n+ ‘dead’ layer thickness from 0.8 to 1.3 mm (x3 for 42K)
Optimized PSD analysis for n+ and p+ surface events
Larger detectors have better surface/volume ratio reducing surface backgrounds

From these developments, we expect a background reduction of at least x5 compared to GERDA/MAJORANA. The background goal will be met.

Feasibility of these required reduction factors have already been shown in GERDA, MAJORANA and in dedicated test stands (e.g. LArGe). LEGEND-200: reduction of backgrounds from 42K, 214Bi, 208Tl by x5 relative to GERDA/MAJORANA.

SLIDE 47

LE LEGEND-200 200 Ba Background Projections

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 47

Monte Carlo

simulations based on experimental data and material assays.

Background rate after

anti-coin., PSD, LAr veto cuts.

Assay limits correspond

to the 90% CL upper

limit. Grey bands

indicate uncertainties in overall background rejection efficiency

Qbb background index upper limit: [0.7–2.0] x10−4 cts/(keV.kg.yr) or [0.2−0.5] cts/(FWHM.ton.yr)

SLIDE 48

2018 2019 2020 2021 2022 2023

LEGEND-200 Purchase Isotope Fabricate Detectors Develop/Install New Lock, Experimental Apparatus

Integration/Commissionin g

LEGEND-200 Data Runs, Goal: 1 t yr (~5-7 years)

GERDA (100 kg yr) MAJORANA (75 kg yr) Earliest, and optimistic, LEGEND-1000 Data Start 2025/6

Ton-Scale Down-Select Process LEGEND-1000 Design/Build, ~6yrs, 2021-2027

Sc Schedules

today

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 48

SLIDE 49

76 76Ge

Ge procu curement

23/01/2020 49

First GeO2 from URENCO (Nl) - 09/18 First metal conversion

f URENCO material

from PPM (Ge). 24.7 kg from ECP (Ru) – 02/19 20.3 kg from URENCO

Yoann Kermaïdic - LPSC seminar - Grenoble

SLIDE 50

Ge Ge detect ctors for LEGE GEND ND-200 200

GERDA BEGes and MAJORANA PPCs

ü Excellent energy resolution ü Superb pulse-shape sensitivity to reject multi-site and surface background events

But relatively small: <m> = 0.66 and 0.85 kg, respectively

New Inverted-Coaxial Point Contact detectors

ü First design proposed in 2011 [R. Cooper et al, 11’] ü Large active mass up to 3 kg ü Excellent pulse shape discrimination performance

[YK et al. 18’]

ü Lower surface to volume ratio ü Reduced background due to lower number of channels per mass of 76Ge ü Production has started early 2019. About 60 detectors expected by fall 2021 BEGe PPC ICPC

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 50

SLIDE 51

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 51

Underground Ge detect ctor ch charact cterization

ICPC travel

Calque sans titre SCK•CEN Canberra Semiconductor nv Ppm Pure Metals GmbH Bremerhaven

MIRION- Olen HADES

HADES lab in Mol

241Am movable source 228Th static source

ü Muon-induded activation and background mitigation ü 6 enriched detectors scanned in October 2019 ü Performances validated (Energy res., op. voltage, …) ü Much more to come in 2020

SLIDE 52

23/01/2020 52

Detec ector R&D &D wi with na natur ural de detec ectors

TUBE @TUM running GALATEA @MPP running scanner @LBL proposal CAGE @UW commissioning scanner @UNC proposal scanner @Queen’s running

Large amount of scanners

in Europe and in the US

Allow for position

dependence response

Crucial for understanding

the Pulse Shape Discr.

Surface scans of ó, ]

and low energy '

Yoann Kermaïdic - LPSC seminar - Grenoble

SLIDE 53

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 53

LA LAr r veto and stri ring as assem embly ly

LAr veto

Ø Take advantage of GERDA experience Ø Design studies + fibers production ongoing Ø Optimization of light collection

14 76Ge detector strings positioning

Ø Extensive Monte-Carlo simulations Ø Compromise between background and cuts efficiency Ø Statistics for weekly calibration

SLIDE 54

Down-selection process in the US

in competition with nEXO – CUPID – (?)

Recommandation from the APPEC

Astroparticle Physics European Consortium

Initial concept includes:
x6 background suppression w.r.t. LEGEND-200
Deeper hosting lab (LNGS under investigation)
LAr veto depleted in 42K
R&D for even larger Ge detectors
Cleaner fabrication process

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 54

LE LEGEND-1000 1000 co considerations

[arXiv:1910.04688]

SNOLAB cryopit concept

6 kg Ge ICPC “mock-up” about a factor of two larger than any previous single-crystal detector!

SLIDE 55

Su Summa mmary

0CDD decay, if discovered, has far reaching consequences in particle

physics! T = T & / LNV / interplay with cosmology (many isotopes needed!)

76Ge isotope offers excellent properties especially

for signal discovery:

Ø Energy resolution, background-free regime, high detection efficiency Ø Possibility to reach }

L/J Mx = 10JI yr sensitivity

Ø “the new physics is at any corner!” therefore we should continue measuring in all directions, regardless of physics models

GERDA and Majorana Demonstrator best technologies provide the

path to next generation experiment

Ø First time to surpass the *-+( yr sensitivity: *. * × *-+( yr (90% CL)

Ø First LEGEND-200 detectors produced Ongoing efforts to start in 2021!

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 55

SLIDE 56

Li Like tr train ains …

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 56

… the most difficult part is to reach the final step … … but we finally make it to the final destination! So let’s remain optimist!

22/01/20

SLIDE 57

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 57

SLIDE 58

LA LAr r veto efficiency

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 58

Energy (keV) 600 800 1000 1200 1400 1600 Counts / 5 keV 500 1000 1500 2000 2500

prior liquid argon (LAr) veto after LAr veto from [EPJC 75 (2015) 9]

1/2

T

b b n Monte Carlo 2 yr × enriched detectors - 53.9 kg

GERDA 18-06

Energy (keV) 1460 1480 1500 1520 1540 Counts / 1 keV 500 1000

K

40

Ar

40

EC

K

42

Ca

42

b

Counts / 5 keV 500 1000

prior liquid argon (LAr) veto in coincidence with LAr veto yr × enriched detectors - 53.9 kg

GERDA 18-06

K

42

K

40

Tl

208

Bi

214

Energy (keV) 600 800 1000 1200 1400 1600 Counts / 5 keV 500 1000

after LAr veto from [EPJC 75 (2015) 9]

1/2

T

b b n Monte Carlo 2

No suppression of 40K – all energy contained in Ge detector High suppression of 42K - ã accompanied with a beta making light in LAr

SLIDE 59

A/ A/E E pul pulse se sha shape pe di discimina nation

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 59

A/E

s (A/E - 1) / 50

50

events after liquid argon (LAr) veto events after LAr veto and A/E cut

GERDA 18-06

Energy (keV) 1000 2000 3000 4000 5000 Counts / 15 keV 1 10

2

10

3

10

after LAr veto and A/E cut 50 keV blinding yr × enriched BEGe - 30.8 kg

A/E

s (A/E - 1) / 50

50

Multi-Site events + Surface low A/E near p-contact Single-Site events high A/E Alpha events on the p-contact high A/E degraded Alpha events

n the p-contact

high A/E Single-Site events band

SLIDE 60

Se Semi mi-co coax de detec ector PSD

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 60

ANN response 0.5 1

events after liquid argon (LAr) veto events after LAr veto and ANN cut

GERDA 18-06

Energy (keV) 1000 2000 3000 4000 5000 Counts / 15 keV 1 10

2

10

3

10

after LAr veto and ANN cut 50 keV blinding yr × enriched BEGe - 30.8 kg

ANN response 0.5 1 Risetime (ns) 100 200 300 400 500

events after LAr veto and ANN cut events after LAr veto, ANN and risetime cut

GERDA 18-06

Energy (keV) 1000 2000 3000 4000 5000 Counts / 15 keV 1 10

2

10

3

10

after LAr veto, ANN and risetime cut 50 keV blinding yr × enriched BEGe - 30.8 kg

Risetime (ns) 100 200 300 400 500

Aritificial Neural Network trained on SSE / MSE discrimination – High alpha rate surviving Risetime cut set to remove fast « p-contact » events – high proportion of alphas

SLIDE 61

GE GERDA ener energy sp spectrum af after all all cu cuts

23/01/2020 Yoann Kermaïdic - LPSC seminar - Grenoble 61

Energy (keV) 1000 1500 2000 2500 3000 3500 4000 4500 5000 Counts / 15 keV 1 10

2

10

3

10

4

10

yr × enriched coaxial - 23.1 kg

GERDA 18-06 b b

Q

after liquid argon (LAr) veto and PSD from [EPJC 75 (2015) 9]

1/2

T

b b n Monte Carlo 2 50 keV blinding

Energy (keV) 1000 1500 2000 2500 3000 3500 4000 4500 5000 Counts / 15 keV 1 10

2

10

3

10

4

10

yr × enriched BEGe - 30.8 kg

GERDA 18-06 b b

Q

after liquid argon (LAr) veto and PSD from [EPJC 75 (2015) 9]

1/2

T

b b n Monte Carlo 2 50 keV blinding