16-May-2002 Weak Interaction Trap for CHarged particles

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INSTITUUT VOOR KERN- EN STRALINGSFYSICA

WI Te +

WITCH:

Physics goals and Present Status

Valentin Kozlov

FANTOM study week, 13-17 May, Paris

16-May-2002 Weak Interaction Trap for CHarged particles

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WITCH team

Outsideworld

F. Ames, D. Beck, G. Bollen, J. Deutsch, J. Dilling, O. Forstner, W. Quint,

and the NIPNET Collaboration

Axel, Bavo, Marcus, Nathal and Valentin

Il’ya, Stefan, Titia and Victor

KO

16-May-2002 Weak Interaction Trap for CHarged particles

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Overview

1. Physics motivation

2. Principle of experiment

3. Experimental set-up

4. Expected results

5. Current status

16-May-2002 Weak Interaction Trap for CHarged particles

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Physics motivation

Weak Interactions: ..int chHHHHH ATVS

0'' TTSS CCCCStandard Model: V-A interaction

08.0V

SC

C13.0V

TC

C 95%CL

e+

e

nucleus

)cos(1)( c

vaW

2

2'2

1V

SS

C

CCa

pure Fermi decay

- correlation:

16-May-2002 Weak Interaction Trap for CHarged particles

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WITCH principle

ScalarVector +

e Recoil energy !

+

e

Scalar Vector

1a 1a

Recoil energy spectrum (eV)5004003002001000

1

0.8

0.6

0.4

0.2

Recoil energy (eV)

16-May-2002 Weak Interaction Trap for CHarged particles

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Penning trap

zeBB

Radial confinement by the homogeneous magnetic field

22

20

2

1

2),( zr

d

UzrU

Axial confinement by an electrostatic quadrupole field

Ion motion in Penning trap:

16-May-2002 Weak Interaction Trap for CHarged particles

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Retardation

!! probes velocity component parallel to electric field !!

conversion of radial into longitudinal kinetic energy necessary

decay trap in 9T –fieldRetardation in 0.1T field

0

1

0

1

B

B

E

Ekin

kin

Magnetic field gradient

retardation

counter

retardationpotential

16-May-2002 Weak Interaction Trap for CHarged particles

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Experimental set-up

%1.19

1.0

0

1

0

1

T

T

B

B

E

Ekin

kin

Energy conversion

High field Magnet (9T)

Low field Magnet (0.1T)

detectorpost-acceleration

einzellens

retardationelectrodes

decaytrap

coolertrap

-detector

16-May-2002 Weak Interaction Trap for CHarged particles

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Charged states

It is possible to measure the charged state distribution!

16-May-2002 Weak Interaction Trap for CHarged particles

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Spectrum

16-May-2002 Weak Interaction Trap for CHarged particles

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Precision

95%CL0.09,CC0.5%Δa VS

95%CL0.06,CC0.2%Δa VS

107105

16-May-2002 Weak Interaction Trap for CHarged particles

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20012000 2002 200319991998

Decision making & design study

Calculations and simulations

Installation horiz. beamline

Inst. Platforms + support

Inst. Last part

Commissioning

First test exp.

Control system creating

Current status

16-May-2002 Weak Interaction Trap for CHarged particles

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Photo gallery

Vertical beamline

Magnet systemSupport structure

Magnet system