Potential for measurement of the tensor electric and magnetic polarizabilities of the deuteron

and other nuclei in experiments with polarized beams

Alexander J. SilenkoResearch Institute for Nuclear Problems

of Belarusian State University

18th International Spin Physics SymposiumCharlottesville 2008

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OUTLINE

Overview Measurement of tensor electric polarizability of

the deuteron by the resonance method Tensor magnetic polarizabilities of the

deuteron and other nuclei in storage ring experiments

Measurement of tensor electric and magnetic polarizabilities of the deuteron by the frozen spin method

Summary

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Methods of measurement of tensor polarizabilities of the deuteron and other

nuclei

Methods of measurement of tensor polarizabilities of the deuteron and other nuclei have been proposed by V. Baryshevsky and co-workers:

• V. Baryshevsky and A. Shirvel, hep-ph/0503214.• V. G. Baryshevsky, STORI 2005 Conference

Proceedings, Schriften des Forschungszentrums Jülich, Matter and Materials, Vol. 30 (2005), pp. 227–230; J. Phys. G: Nucl. Part. Phys. 35, 035102 (2008); hep-ph/0504064; hep-ph/0510158; hep-ph/0603191.

• V. G. Baryshevsky and A. A. Gurinovich, hep-ph/0506135.

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V.G. Baryshevsky and co-authors:

The tensor electric and magnetic polarizabilities of the deuteron manifest in the EDM experiment

with vector-polarized deuterons and can be measured

•The tensor electric polarizability stimulates the buildup of the vertical polarization of vector-polarized deuteron beam•The tensor magnetic polarizability produces the spin rotation with two frequencies instead of one, beating and causes transitions between vector and tensor polarizations

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The tensor electric and magnetic polarizabilities affect the spin

2 2' ' .T TV

S E S B

'E 'Band are the rest frame fields

2

2 2.T

zT

z z

V B S E S

B S

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There are two resonance frequencies, ω≈ω0 and ω≈2ω0:

2 2 2 20 0 0 0 0 0

2 2 4 40 0 0

0 0

0

0

2

c

cos

2

12 5 3

4

2 t+

os

1 .

t

A. J. Silenko, Phys. Rev. C 75, 014003 (2007).

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We use the matrix Hamiltonian for determining the evolution of the spin wave function:

1

0

1

, .

C tdi H C tdt

C t

Measurement of tensor electric polarizability of the deuteron by the resonance method

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The polarization vector and tensor:

The spin matrices:

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2 2

2

1 0 1 1 0 11 1

0 2 0 , 0 2 0 ,2 2

1 0 1 1 0 1

0 0 1 1 0 0

0 0 0 , 0 0 0 ,

1 0 0 0 0 1

x y

x y y x z

S S

S S S S i S

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Measurement of tensor electric polarizability of the deuteron by the resonance method

E

Y. F. Orlov, W. M. Morse, and Y. K. Semertzidis, Phys. Rev. Lett. 96, 214802 (2006).

Resonance Method of Electric-Dipole-Moment

Measurements in Storage Rings

Oscillating longitudinal electric field stimulates an oscillation of

particle velocity in resonance with spin precession

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Initial matrix Hamiltonian:

0 0

0

0 0

0

0 2 0 ,

0

E

E

E

A B A

H A

A A B

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Connection between the polarization vector and tensor and the spin amplitudes:

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Vector- polarized beam (initial horizontal polarization):

Θ and ψ are spherical angles

Tensor- polarized beam (initial horizontal polarization and Sl = 0):

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Weaker resonance at the frequency ω≈ω0

Stronger resonance at the frequency ω≈2ω0

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Final vertical beam polarization forinitial horizontal vector polarization and ω≈ω0:

Final vertical beam polarization forinitial horizontal tensor polarization and ω≈2ω0:

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Theoretical data

Tensor electric polarizability of deuteron:

αT = −6.2 × 10−41 cm3

αT = −6.8 × 10−41 cm3

αT = 3.2 × 10−41 cm3

J.-W. Chen, H. W. Grießhammer, M. J. Savage, and R. P. Springer, Nucl. Phys. A644, 221 (1998).

X. Ji and Y. Li, Phys. Lett. B591, 76 (2004).

J. L. Friar and G. L. Payne, Phys. Rev. C 72, 014004 (2005).

Tensor magnetic polarizability of deuteron:

βT = 1.95 × 10−40 cm3

J.-W. Chen, H. W. Grießhammer, M. J. Savage, and R. P. Springer, Nucl. Phys. A644, 221 (1998).

X. Ji and Y. Li, Phys. Lett. B591, 76 (2004).

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Estimated expirimental sensitivity of the resonance method

Tensor electric polarizability of deuteron:

δαT ~ 10−45 ÷ 10−44 cm3

(initial tensor-polarized beam)

A. J. Silenko, Phys. Rev. C 75, 014003 (2007).

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Tensor magnetic polarizabilities of the deuteron and other nuclei in storage ring experiments

Tensor magnetic polarizability of the deuteron can be measured without both a resonance field and a restriction of spin rotationOnly vertical magnetic field is used

2 2

2

1,

2

.

zT

zT

B

B

A

B=

A. J. Silenko, Phys. Rev. C 77, 021001(R) (2008).

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When the direction of the initial tensor polarization is defined by the spherical angles θ and ψ,

0

0

2 2

( ) sin 2 sin sin ,

( ) sin 2 cos sin ,

( ) 0,

1.

2

z

T T z

P t t bt

P t t bt

P t

b B

B A

When t ~ 1000 s, P║ ~ 1 %. This polarization is measurable.

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Measurement of tensor electric and magnetic polarizabilities of the deuteron by the frozen spin

method

2

1.

1 1a

e aa a

m

ω B β β B β E

2

2 2

2, 0, .

2 1 z

aga E B

a

β B

The spin orientation relatively the momentum direction remains unchanged!

F. J. M. Farley, K. Jungmann, J. P. Miller, W. M. Morse, Y. F. Orlov, B. L. Roberts, Y. K. Semertzidis, A. Silenko, and E. J. Stephenson, Phys. Rev. Lett. 93, 052001 (2004).

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dd

23

2 2

2 2.z

T

zT

zV B E S

B E S

22 2 2 2

22 21 .

1T Tz zV B a S S

a

2 22

22 2

222 2

1,

2 1

.1

z

T

T

z

aB

a

Ba

A

B=

Correction to the Hamilton

operator

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When the direction of the initial tensor polarization is defined by the spherical angles θ and ψ,

0 00

0 00

20 0

0

22 222 2

( ) sin 2 sin sin sin ,

( ) sin 2 cos sin cos ,

2( ) sin sin sin 2 ,

11 .

21T T

z

z

P t bt t t

P t bt t t

P t t t

b B aa

A

A

A

B A

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The frozen spin method provide a less experimental sensitivity of measurement of the

tensor electric polarizability of the deuteron than the resonance method

Nevertheless, well-controlled dynamics of the horizontal spin components can improve the

experimental conditions of measurement of tensor magnetic polarizability of the deuteron by the frozen

spin method as compared with other methods

The frozen spin method provides a weaker magnetic field than other methods

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V.G. Baryshevsky, A.A. Gurinovich, Nucl. Instrum. Meth. B 252, 136 (2006).

Particle motion in bent and straight crystals is accompanied by a rotation and an oscillation of the particle spin that allows to measure the tensor electric and magnetic polarizabilities of nuclei and elementary particles

When 1<g<2 and γ=g/(g-2), the electric field of a bent crystal does not influence the spin and the effect of the tensor polarizabilities can be measured with a vector-polarized beam

If one uses an initial tensor-polarized beam, the effect of the tensor polarizabilities can be measured for arbitrary g and γ in both bent and straight crystals

However, the effects are very small: an additional vector polarization of the beam is of order of 10-4 or less

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Summary Spin dynamics caused by the tensor electric and

magnetic polarizabilities of the deuteron and other nuclei in storage rings is calculated

Potential for the measurement of the tensor polarizabilities of the deuteron and other nuclei in experiments with polarized beams is investigated

For the tensor electric polarizability of the deuteron, the resonance method provides the experimental sensitivity of the order of 10−45 ÷ 10−44 cm3

Both a purely magnetic ring and the frozen spin method can be used for the measurement of the tensor magnetic polarizability of the deuteron

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Thank you for attention