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Page 1: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

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Page 2: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

���� ���

• 1937 Zwikcy �������� ��������

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2019/12/12

F.Zwicky, AstroPhys. J. 86 (1937) 217.

Page 3: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

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•���������

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2019/12/12

Y.Sofue and V.Rubin, Ann. Rev. Astron. Astrophys. 39 (2001) 137.

Page 4: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

AMS-02������������

2019/12/12

• Alpha Magnetic Spectrometer

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ppZllZ+®®++®®+

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Page 5: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

AMS-02�����

• 60 GV�������

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• 30~70 GeV/c2

• !" ≈ (1~6)×10+,- cm3/sec

2019/12/12AMS Collab. Phys. Rev. Lett. 117 (2016) 091103

Page 6: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

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2019/12/12

!"# = %"#&"#

Page 7: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

2019/12/12

AXION, AXION-LIKE-PARTICLES (ALP)

• �� ��� CP��#������$���"

• Axion���� ���

• �� %(*&+$��• Axion �������%(*&+�)+'

• Heavy Axion ( keV,�!����

L. Di Lella and K. Zioutas, Astropart. Phys. 19, 145 (2003).

Page 8: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

STRONGLY INTERACTING MASSIVE PARTICLES (SIMPs)

• 3��������

• !"#~%&'' (&)* +,-./0~100 MeV

%&'' ≈ 1�DMself-interaction

2019/12/12

Y.Hochberg et al., Phys. Rev.Lett. 113 (2014) 171301.Y.Hochberg et al., arXiv:1402.5143.

S.M.Choi et al., arXiv:1707.01434.

Page 9: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

WEAKLY INTERACTING MASSIVE PARTICLES (WIMPs)

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; ��5.7/734�.�<

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• ���18/,>�����)

2019/12/12

G.Jungman, M.Kamionkowski, and K.Griest,Phys. Rep. 267 (1996) 195.

Page 10: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

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2019/12/12

Page 11: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

WIMP���

2019/12/12

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Page 12: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

244km/sec

30km

/sec

Annual modulation in WIMPs energy spectrum.A.Drukier et al., Phys. Rev. D33 (1986) 3495.K.Freese et al., Phys. Rev. D37 (1988) 3388.

Page 13: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

2019/12/12.kgday s km 230cmGeV 4.0pb 1

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J.D.Lewin and P.F.Smith, Astroparticle Physics 6 (1996) 87.

Page 14: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

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01482.1

energy recoil a give to WIMPsof speed minimum The :

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Page 15: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

�������

•������ ���

eN ZmMAcm -D+= 478.931)/GeV( 2

2/MeV 511.0 cme = ����

⊿M [MeV/c2] ��mN[GeV/c2]

23Na -9.528 21.409127I -88.984 118.18

2019/12/12

Page 16: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

FORM FACTOR � QUENCHING FACTOR

!(#) = 3'((#)*)#)*

exp −(#/)0

2 ,

'((#)*) =1

#)* 0 sin( #)*) − #)* cos( #)*)

#(MeV/<) = 2=*>? : Momentum transfer.)* = 1.18I(/J : Nuclear radius.#N = 0.09 : The quenching factor of iodine ion in NaI(Tl).#*V = 0.25 : The quenching factor of sodium ion in NaI(Tl).

2019/12/12

Page 17: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

������� ���� �NaI(Tl)�

• I, mx=50 GeV/c2

• σp-x=1 pb

Cross over of event rate Cross over of event rate

• Na, mx=50 GeV/c2

• σp-x=1 pb

Black; June Red: December

Page 18: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

�� ����

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• 40K β K-X�3 keV)

• 210Pb β ���(46.5 keV) L-X(10~17 keV)

2019/12/12

Page 19: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

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2019/12/12

2013� ��

Page 20: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

ALP���

2019/12/12

Phys. Rev. Lett. 113 (2014) 12301

Page 21: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

CRESST

2019/12/12H.Cluck et al.,arXiv: 1711.01285

CdWO4 Cryogenic

Page 22: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

Technology Implementation Status Sensitivity CUTE

DAMA

DAMACD

MS Si

LUX 2013

DEAP

CDMS II 2015

DAMIC 2016

SuperCDMS LT 2014

CRESST2015

CDMSlite

2015

Solar Neutrinos

Atmospheric Neutrinos

Si HV

Si iZIP

Ge

HV

Ge

iZIP

LZ

Sensitivity 22

XENON1T 2017

Goal

Longtermgoal

������ ��

SuperCDMS : TAUP2017

Page 23: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

XENON 1T

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• PI ���������������

2019/12/12

E.Aplire et al.,arXiv:1705.06655

Page 24: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

NaI(Tl)1736828'��

•DAMA/LIBRA(���/#�.+&�

• Xe����$-��#�)"!+&�

•��28045$ �(��

• Xe(���9*���!,���%���%�� .�*

2019/12/12

Page 25: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

2019/12/12

Page 26: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

2019/12/12

Page 27: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

2019/12/12

Page 28: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

DAMA���

• PICOLON

•DM-ICE

• KIMS

• SABRE

• ANAIS

2019/12/12

R.Maruyama talk in TAUP2017

Page 29: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

����������������'$��!���(���

• ���������"!1�'#��'$������'#�##

• �)+(&./"#��������2��������"!1�'#��'$

!,�&0��������� 0���!-.,*�+%���

Page 30: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

2019/12/12

Page 31: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

2019/12/12

Page 32: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

ANAIS-112 (112 kg NaI(Tl) )

•No significant modulation.

• Phys.Rev.Lett.123, 031301 (2019)

Page 33: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

2019/12/12

Page 34: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

PICOLON

2019/12/12

• Pure Inorganic Crystal Observatory for LOw-energy Neutr(al)ino

• ��������������Univ. South Dacota

• I.S.C.Lab.

Page 35: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

Status of NaI(Tl) purification(~April 2019)RI Ingot26

(2015)Ingot37(2016)

Ingot71(2018)

Ingot76(2019)

Goal

Size 3”φX3” 4”φX3# 3”φX3” 5”φX4” 5”φX5”40K (ppb) 2630 120 <20 <20 <20 �232Th (ppt) 0.4�0.5 3.7�0.5 1.7�0.2 -- <4 �238U (ppt) 4.7�0.3 5.9�0.3 9.7�0.8 4.4�0.2 <10 �210Pb (μBq/kg)

30�7 2300 1076 ~560 <50

Method Resin for Pb I26+cation resin

double re-crystallization

Pb resin + double re-crystallization

• U-chain: 1ppt= 12.3μBq/kg

• Th-chain: 1ppt= 4.0μBq/kg

• 210Pb: 1ppt=2.5kBq/kg

Page 36: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

BG STATUS OF INGOT #76

Still high BG of alpha rays.~1000 μBq/kg (46.5 keV gamma from 210Pb.)~560 μBq/kg (Alpha ray from 210Po.)

210Pb

126I125I

EV

EN

TS/k

eV/d

ay/k

g

Page 37: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

��'��&#�$

•��• .1-*�"$�) ���(���$�)�%�•Mean event rate = 1/day/keV/kg�mdet�7 day

• 371 events / 53 kg (9 modules)• 1734.6 events / 247.8 kg (42 modules)

•�����*�&�$/+,0��'��*��� !�.

2019/12/12

Page 38: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

��

� � � �

������

������

����

#������� "���� �����!�����

%'(�

��������������

��� ���� ����

���� &$)�

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� � � �

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#������� "���� �����!�����

%'(�

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�������&$)�

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53 KG 250 KG

• Upper limits• 0.022/day/keV/kg 0.0035 /day/keV/kg

Page 39: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

DETECTOR STABILITYXMASS��

������ �� 39

+/-0.5%

+/-0.5%

MC deduced scintillation light yield

MC deduced scattering length (cm)

MC deduced absorption length (m)

Observed PE yield (PE/keV)

• We carried out weekly 57Co calibration to monitor PE yield.

• We observed PE yield changes at power outage. According to the MC simulation, it is due to the change of the absorption parameter.

• In our analysis, the systematic error of this data handling is taken into account.

2019/12/12

Page 40: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

MODEL INDEPENDENT ANALYSIS

������ �� 40

Method 1(pull term)

Method 2(covariant

matrix)

ndf 1709 1710

Minimum χ2 1845.0 1901.7

χ2 at no modulation

1912.3 1961.8

p-value 0.068 (1.8σ) 0.17 (1.4σ)

Method 1 (pull term)Method 2 (covariance matrix)

• 1.1keVee (5keVr) analysis threshold

• The difference of two methods are small.

• Small negative amplitude is observed in 0.5-3keVee

region. But both results are consistent, but not statistically significant.

2019/12/12

Page 41: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

"�� ��CALCULATING SENSITIVITY PLOT

•&+-'.),(*- ����� ���%��

•&+-'. ��%��#

• 1~2 keVee : 2~3 keVee : 3~4 keVee : 4~5 keVee : 5~6 keVee

•�$�$ �"�� �����%�!

2019/12/12

Page 42: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

�����

•Na recoil

• 54 kg�3 years

• Thin line = Xenon1T

• Thick lower line = Neutrino BG

2019/12/12

Page 43: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

PICOLON�������

9 modules (53 kg)42 modules (247 kg)

E�1 keVee, BG=1 /day/keVee/kg

Page 44: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

54 kg NaI(Tl)~2020��(A)��

250 kg NaI(Tl)~2024�� ��

KamLAND-PICO1000 kg NaI(Tl)~2025

SCALE UP

�������������

Page 45: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

NaI(Tl)(�

•���'�����#�"!*7•���(16/23(Xe)$�#�*&�(�7

•���'����� ,!*7• NaI(Tl)( *&+����?

•)�(���$�(%�-.�+�����045�� �

2019/12/12

Page 46: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

!,�*��"(���

•���'��

•� ��$)��&��-�*,+�7

•���'���

•�.24/6$β/γ%� ��-��$�+�7

•� #�'3560146���

2019/12/12

Page 47: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

•NaI(Tl) Xe�����

2019/12/12

Page 48: 応用物理学科-岡山理科大学 理学部nagao/slide/20191212_fushimi_s.pdf · 2021. 1. 10. · PULSE SHAPE DISCRIMINATION STUDY •Half-inch crystal grown by Bridgman method

PERFORMANCE EVALUATION OF CaI2

• Emission wavelength (WL) and light yield (LY) were studied using a small piece of CaI2.

• Emission WL : 410 nm, Excitation WL : 300 nm• From photo-electric peak of 662 keV gamma-ray, LY

was estimated as 107,000 ph./MeV (10 � Liq. Scint.).

CaI2(Peak at 410 nm)

CaI2 = 2.7� NaI(Tl)

K. Kamada, T. Iida et al., Ceram. Int., Vol. 43, Suppl. 1, August 2017, Pages S423-S427

T.Iida, SCINTI2019

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PULSE SHAPE DISCRIMINATION STUDY• Half-inch crystal grown by Bridgman

method.

• 5mm square and 1mm thick piece was sliced off in a dry room whose humidity was kept below 3%.

• Crystal was directly set on PMT and irradiated by alpha-ray source (241Am) and gamma-ray source (137Cs).

• Waveform of 10 thousand events for a/b were aquired by waveform digitizer with 400MHz sampling rate.

R7600-200UUltra-bialkali PMT

Waveform Digitizer400MHz sampling rate

T.Iida, SCINTI2019

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AVERAGE WAVEFORM FOR A / B

Beta

Alpha

• Average waveform for a/b were calculated from 10 thousand events and fitted by multi exponential function.

• Slow component of ~800 ns and fast component of ~100 ns was obtained both for aand b.

• Very short component (18 ns) was appeared only in a.T. Iida et al., Nucl. Inst. nd Meth. A, to be published DOI: 10.1016/j.nima.2019.162629

T.Iida, SCINTI2019

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A/B SEPARATION BY “RATIO”

• Obtained figure of merit was

FoM = 4.2 for CaI2 in 400 – 700 keV.

ref. FoM = 2.0 for CaF2(Eu)

• Very good PSD capability was verified!!

To evaluate PSD power, we defined “Ratio” and “Figure of Merit” as follows.

!"#$% = '$()# *++ ,) -./0%#"1 -./

'%2 = 34 − 3674 + 76

Energy [keV]

Alpha

Beta

AlphaBeta

T.Iida, SCINTI2019

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(:73

• XMASS��(2018�)1��4�$����5��+.6'2��32/0&8%

•���#4?G=;�*�+0@>BDFAG329'%

• #� NaI(Tl)1���"→ -4�4��)��

• <DCEG=I;��!�1,HH

2019/12/12