Поиск ЭДМ нейтрона Поиск ЭДМ нейтрона кристалл-кристалл-дифракционным дифракционным методомметодом

Воронин Владимир

ПИЯФ, Гатчина

Секция ЯФ ОФН РАН, ИТЭФ 2011April 21, 2023 1

Neutron EDMNeutron EDM

Non zero EDM means the P Non zero EDM means the P and T violation and T violation

P P – spatial inversionСС – particle – antiparticle inversion Т Т – time inversion

CPTCPT theoremtheorem(Lüders (1954); Pauli(1955))

(Our world is (Our world is СРТСРТ invariant)invariant)

Non zero nEDM meansNon zero nEDM means СРСР violationviolation

April 21, 2023 2

History of nEDM experimentHistory of nEDM experiment

Standard model

dn~(10-31-10-33) e cm

New physics to explain the New physics to explain the baryon asymmetry baryon asymmetry (experiment - (experiment - nnbb/n/n~10~10-11-11

SMSM -- nnbb/n/n~10~10-21-21))

dn~(10-25-10-30) e cm

Neutron scattering

in-flight magnetic resonance

UCN magnetic resonance

April 21, 2023 3

Idea nEDM experimentIdea nEDM experiment

2(E·D)

-E

+EDD

DD

Interaction time

with Е

1 ~ E N

2( ) /D E D

Sensitivity to nEDMSensitivity to nEDM

Neutron size Rn ~ 10-13 cm,

dn/Rn ~ 3 10-13. Corresponding size from Corresponding size from

Earth is Earth is ~ 2~ 2 μμmm

Current accuracy to dCurrent accuracy to dnn

April 21, 2023 4

Sensitivity to neutron EDMSensitivity to neutron EDM

E~ grad Ve ~(0.1-1)GV/cmUCNUCN methodmethod

Crystal-diffraction methodCrystal-diffraction method

E ~ 10 kV/cmτ ~ 1000s (time of life)ЕЕττ ~ ~ 101077(V·s)/cm (V·s)/cm Now ЕЕττ ≈ 106 (V·s)/cm

τa ~ 0.01 c (absorption)

10107 7 (V(V·s)·s)/cm/cm

ЕЕττ

1 ~ E N Electron bonding energy ~ a few eV

~ 1 ÅÅ

April 21, 2023 5

+-

Neutron optic of NCS crystalNeutron optic of NCS crystal

( ( ))( ) 1 g i

K

i

K g

Ve

Ee

E

kr grr

•M. Forte, J. Phys. G: Nucl. Phys. (1983) 745-754.•V. G. Baryshevskii and S. V. Cherepitsa, Phys. Stat. Sol. B128 (1985) 379-387. • V. V. Fedorov, Proc. of XXVI Winter LNPI School, vol. 1, Leningrad (1991) 65.

2 | |( ) | ( ) | ( ) g

K Kg

VE

E E

gE r r r E

Wave functionWave function

g

d

L

V||

v

k

k+g

Electric fieldElectric fieldDeviation

from Bragg condition

Electric field depends Electric field depends onon a deviation from Bragg a deviation from Bragg conditioncondition EE(Neutron energy)

April 21, 2023 6

/2

2d 0 sin ( θ B )= λ

Idea of the experimentIdea of the experiment

F or (1 1 0 ) p lane ofq uartz c rysta l

T = 1 0K

/ 1 0 -5 =B /For /2 reflection

E || vn and

Hs~[E x vn]≈0

+E+E -E-E

April 21, 2023 7

Electric fieldElectric fieldquartz (110) plane Lc=14 cmBragg angle ≈ 860

-0.8·108 V/cm

Theory

+ 0.8·108 V/cm

Variation of the T on 1K

E E ≈≈ 10 108 8

V/cmV/cm

April 21, 2023 8

Test experimentTest experimentPNPIPNPIV.V. Fedorov, E.G. Lapin, I.A. Kusnetsov, S.Yu. Semenikhin,

V.V. Voronin

ILLILLM. Jentschel, E. Lelievre-Berna, V. Nesvizhevsky, A. Petoukhov, T. Soldner, F.Tasset

April 21, 2023 9

Layout of the Layout of the experimentexperiment

T = T 0T = T 0

(1 1 0 ) p la n e

P G (0 0 2 )(R ~ 5 0 % )

(1 1 0 ) p la n eM e is s n e r c a v ity

H L03He cell

n P S D

S p in flip p e r P F 1 b

Z

X

Y

B e a m s to p

B e a m s to p

S M p o la rize rD o u b le c rys ta lP G m o n o c h ro m a to r

in c o m in gn u ta to r

o u tg o in gn u ta to r

C asem at

+ E -Ev n

-P D

+ P D

E n> E 0

E n< E 0

M on itor

.

6 m

April 21, 2023 10

nEDM measurementnEDM measurement

0 5 10 15 20 25

-0,002

0,000

0,002

0,004

0,006

Runs

PXY

PYX

ddnn=(2.4=(2.46.5)106.5)10-24-24 e cm e cm

-4(0.6 2.3)10XYP -4(1.9 2.2)10YXP

-4(0.6 1.6)10dP

P0=0.82KBG= 0.85

-4(0.9 2.3)10d

Kr=0.7

E=E= (0.7±0.1) 10(0.7±0.1) 1088 V/cm V/cm

April 21, 2023 11

Improvement the sensitivity for Improvement the sensitivity for current geometry of current geometry of experimentexperimentTest

setupFull scale setup Kimp

Crystal size, cm 14x2x2 50x10x10 3.6

Beam size, cm 27S=5.7

6x12S=72

3.6

Beam collimation, sr

(4/700)2=3.2 ·10-5

(12/450)2

=7.1 ·10-44.7

Reducing the background

0.85 1 1.17

Absorption in quartz

0.84 0.54 0.8

KKss=57=57

1.6 101.6 10-23-23

ddnn,,e cm e cm

per dayper day

2.8 102.8 10-25-25

April 21, 2023 12

-1 0 1 2 3 4 5 6 7 8 9 10 11

1,5

2,0

2,5

3,0

3,5

4,0

4,5

W, 1

0-5

Crystal number

Crystal quartz testCrystal quartz test

Now we have quartz crystal withsummary size

100x100x500 mm3 with d/d~ 4 10-6

April 21, 2023 13

Доклад Семенихина С.Ю.

April 21, 2023

3-D analysis of neutron polarization

Magnetic field || surface of the superconductor.

HL≈0 HL≠0

P

Current accuracy of spin Current accuracy of spin orientation isorientation is

~10~10-2-2 rad rad for routine experiment

~10~10-3-3 rad rad can be reached for special casesF. Tasset, P.J. Brown, E. Lelie`vre-Berna, T. Roberts, S. Pujol, J. Allibon, E. Bourgeat-

Lami, Physica B, 267-268 (1999) 69-74

14

April 21, 2023 15

CRYOPAD-D under constructionCRYOPAD-D under construction

Size - 60cm 60cm Beam aperture –10x10 cm10x10 cm2 2

Nutator fields homogeneity – 1010-3-3

Crystal Symmetry group

hkl d, (Å) Eg,108V/cm

a,

ms

Eg a,(kVs/cm)

-quartz(SiO2)

32(D63) 111 2.236 2.3 1 230

110 2.457 2.0 200

Bi12SiO20 I23 433 1.75 4.3 4 1720

444 1.46 4.65 1860

Bi12GeO20I23 433 1.74 4.65 1 465

444 1.46 4.8 480

PbO P c a 21 002 2.94 10.4 1 1040

004 1.47 10 1000

BeO 6mm 011 2.06 5.4 7 3700

201 1.13 6.5 4500

Parameters of some NCS Parameters of some NCS crystalscrystals

!!! We should looking for new NCS crystal !!!!!! We should looking for new NCS crystal !!!April 21, 2023 16

Storage variantStorage variantt=0

0<t<2ta

t=2ta3He cell Detector

Hf

Hi

Perfect crystal reflectionT=T0

T=T0T T=T0T

Up to 1000 reflections (s~1 s)M.R. Jaekel, C.J. Carlile, E.Jericha, D.E. Schwab and H. Rauch, SPIE Vol. 3767 EUV, X-Ray, and Neutron Opticas and Sources, 353 (2000)

April 21, 2023 17

Some numerical estimationSome numerical estimation

Bragg width –

Responsible time –

Crystal acceleration –

(fast piezoelectric element?)

(444)40.6 /g BSO

Bc

F dv cm s

mV

15~ 2 / ~ 0.2L cmr nL v ms

/ ~ 30 / 3c B ra v m s g

April 21, 2023 18

Sensitivity estimation Sensitivity estimation

Eg,108V/cm

,ms

Count rate Kg d, ecm

per day

-quartz

(110) in-flight

2.0 0.6(L=50cm)

104 n/s(ILL PF1)

(2-3)10-25

Bi12SiO20 (444)storage

4.65 8(L=15 cm)

103 n/s(ESS - SP)

10 (2-3)10-26

April 21, 2023 19

ConclusionConclusion Full-scale setup with quartz crystal could

have a sensitivity dd~(2-3)~(2-3)··1010-26-26 e e··cm cm per per

100 day of measurement100 day of measurement

Storage modification of crystal-diffraction

nEDM experiment could reach a sensitivity

dd~(2-3)~(2-3)··1010-27-27 e e··cm cm for the short pulse ESS

and BSO crystal

April 21, 2023 20

April 21, 2023 21

Summary of the systematic

5~ 10 /r Gs hourH

4~ 10r GsHResidual magnetic field

Value

Time stability

3D analysis of polarization3~ 10y rad

d n < 1 0 -2 6e c m

The crystals alignment

The ΔT0 control ~0.010K

~0.01 arc degree~0.01 arc degree

Flat windows of CRYOPAD4~ 10f rad

P odd rotation is4 3 7

0

10 10 10P P

dn~10-27 e cm