Nathal Severijns Kath. Universiteit Leuven, Belgium

04/21/23

Nathal Severijns

Kath. Universiteit Leuven, Belgium

+

e

eurorib’10 conferenceLamoura, 6-10 June 2010

Fundamental interaction studieswith radioactive nuclei

1N. Severijns, eurorib'10 conference - June 6-10, 2010

04/21/23 2N. Severijns, eurorib'10 conference - June 6-10, 2010

1. searches for exotic weak currents (non V-A)

- tensor currents

- scalar currents

- right-handed currents

2. Vud and CVC

3. atomic parity violation

- Fr (Legnaro)

- Ra, … (KVI-Groningen)


1. searches for exotic weak currents (non V-A)

- tensor currents

- scalar currents

- right-handed currents

2. Vud and CVC

for right-handed exotic couplings

(1, 2 and 3 contours of equal 2)

N.S., O. Naviliat-Cuncic, M. Beck,

Rev. Mod. Phys. 78 (2006) 991


e+

e

nucleus

e

e

p qa

E E

Correlation measurements in nuclear decay

Fierz interference term( b 0 in standard model )

-correlation

asymmetry

J ,

= 1

e

e

mb

XX

E

J.D. Jackson et al., Nucl. Phys. 4 (1957) 206

e

e

pJA

J E

qJ

BJ E

asymmetry

most experiments determine:

21 ( )Z

e+

e

nucleus


2A

2'T

2T

2V

2's

2S

|C|

|C| |C| 1

3

1

|C|

|C| |C| 1

GT

F

a

a

-correlation

A

'TT

V

'SS

C

C C e

C

C C e

Rb

Rb

GT

F

(assuming maximal P-violation and T-invariance for V and A interactions)

recoil corr. (induced form factors) 10-3 ; radiative corrections 10-4

2with 1 ( )Z

experimental observable:

= 1

e

e

mb

E

aa

e

e

p qa

E E

search for exotic scalar couplings with 38mK

TRINAT MOT trap at TRIUMF-ISAC (J. Behr et al.)

38m 38 +K Ar + e + ν

superallowed 0+ 0+ pure Fermi transition (t1/2 = 0.95 s)

Traps: ideal source - sample is isotopically pure - localized in small volume - atoms decay at rest - negligible source scattering - potential for polarized sample


A. Gorelov, J. Behr et al.,PRL 94 (2005) 142501

= 0.9981 (30) (3 = ) 1

5e

e

stat syst

aa

mb

E

2 ' 2

2

(90% C.L.)

| | | | 0.097

|

|SS

V

C C

C

( = 1)SMa

04/21/23 7

angular correlation for Magneto-Optically Trapped 21Na

P. A. Vetter, S. J. Freedman et al., Phys. Rev. C77 (2008) 035502

2500

2000

1500

1000

500

0

cou

nts

25002000150010005000time of flight (ns)

21Ne

+

21Ne

+2

21Ne

+3 21Ne

0

2500

2000

1500

1000

500

0

Net

Counts

900800700600500400300

Time of Flight (ns)

-404

Resid

uals

Trap Data Monte Carlo Fit

aexp = 0.5502 ± 0.0038 ± 0.0046aSM = 0.5587 ± 0.0027

Result:

Recoil-ion TOF

04/21/23 8

O. Naviliat et al.

LPC-Caen Paul trap at GANIL (O. Naviliat-Cuncic et al.)

GT

04/21/23 9

04/21/23 10N. Severijns, eurorib'10 conference - June 6-10, 2010 10

LPC-Caen Paul trap at GANIL (O. Naviliat-Cuncic et al.)

(tensor)

(axial-vector)


K.U.Leuven, Uni. Munster, ISOLDE, GSI, NPI Rez-Prague (N.Severijns et al.)

Goal : measure correlation for 35Ar with (a/a)stat 0.5 %

• Detect recoiling ions in singles (MCP)• Determine ion energies with retardation potential

WITCH Penning trap at ISOLDE - search for scalar weak currents

M. Beck et al., NIM A 503 (2003) 567 IS433-experiment

pulse heightdistributionions

’s

Preliminary

Retardation potential (V)

124Sn recoils

First First recoil ion spectrum

proof of principledemonstrated

V.Yu. Kozlov et al., NIM B 266 (2008) 4515

MCP signal

KVI-Groningen04/21/23 12N. Severijns, eurorib'10 conference - June 6-10, 2010


asymmetry

experimental observable:

= 1

e

e

mb

E

AA

J

e

e

pJA

J E

for a pure Gamow-Teller transition :

'T T

J'JA

C + C 1 Re

CGTe

γmA

E

A = 0.01 (for m/Ee 0.5) Re [(CT+CT’) / CA] < 0.033 (90% CL)

(assuming maximal P-violation for V, A interactions and and time reversal invariance )

21 ( )Z


regionanalysed

no energy dependence left corrections OK

Recent asymmetry measurementsat Leuven and ISOLDE (IS431)

with 60Co, 67Cu and 114In

see talk of Frederik Wauters

F. Wauters et al.,NIM A 609 (2009) 156,PR C 80 (2009) 062501PR C submitted

04/21/23 N. Severijns, eurorib'10 conference - June 6-10, 2010 7

Polarizing atoms/ions in a particle trap:

- Paul trap : optical pumping of ion cloud (LPC-GANIL) in magnetic holding field

- Penning trap : collinear polarization by optical pumping(WITCH-ISOLDE, DESIR) in beam line before trap

- MOT trap : optical pumping of ion cloud (TRIUMF, Berkeley, KVI) in magnetic holding field

Alternative : stop ions in superfluid He and polarize by optical pumping (T. Shimoda et al. - TRIUMF)


37K – D. Melconian, J.A. Behr et al., Phys. Lett. B 649 (2007) 370

37( ) 0.755(24)

0.779(6)SM

B K

B

polarized atoms in a MOT B neutrino asymmetry parameter for 37K

5 % precision

very difficult to determine nuclear polarization precisely !

TRINAT MOT trap @ TRIUMF

qJ

BJ E

asymmetry

J


D. Melconian, J.A. Behr et al., Phys. Lett. B 649 (2007) 37037K

80Rb J.R.A. Pitcairn, J.A. Behr et al., Phys. Rev. C79 (2009) 015501

Polarization by optical pumping and determination of nuclear polarization via photoionization in a MOT

04/21/23 18

80Rb – J.R.A. Pitcairn, J.A. Behr et al., PR C 79 (2009) 015501

Asymmetry parameter of recoil ions with 80Rb in MOTJ. Behr et al. - TRIUMF

recoil SM TA A A 0 0.015 0.029 0.019SM T stat systA A B A

interpretation difficult due to recoil terms(quark bound in nucleon ! 0.1 – 1 % effect)

04/21/23

Longitudinal polarization of positrons emitted by polarized nuclei

with : P- (P+) the particle longitudinal polarizationfor ’s emitted opposite to (in the direction of) the polarized nuclear spin vector

(P0 for unpolarized nuclei)

(M)LRS-models

W1 = WL cos - WR sin

W2 = WL sin + WR cos

= (mW1)2 / (mW2)2 19N. Severijns, eurorib'10 conference - June 6-10, 2010

04/21/23

1) N. Severijns et al., PRL 70 (1993) 4047, 73 (1994) 6112) M. Allet et al., Phys. Lett. B363 (1996) 1393) E. Thomas et al., Nucl. Phys. A694 (2001) 5594) N. Severijns et al., Nucl. Phys. A629 (1998) 423c

signal

Results :

MW2 > 320 GeV/c2 (90 % C.L.)


Isotope k sensitivity to

MW2 [GeV/c2]

(90% C.L.)17F 32.2 604

21Na 12.5 47725Al 15.7 50541Sc 18.8 52812N 17.9 522107In 25.7 571

for Pnucl = 0.80 & 1% precision on P- /P+

21

0.180.24

0.97425(22) 0.22521(94) 0.00393(36)

0.230(11) 1.04(6) 0.0412(11)

0.0081(6) 0.0387(23) 0.77

0.99990(60)

(masses, decays theory, …)

from K decays

strong limits on physics beyond Standard Modele.g. - scalar currents - right-handed currents

04/21/23

Vud and CVC

N. Severijns, eurorib'10 conference - June 6-10, 2010

recent review:I.S. Towner & J.C. HardyRep. Prog. Phys. 73 (2010) 046301


strong limits on physics beyond Standard Model

e.g. - scalar currents

- right-handed currents : = 0.000 05(30)

- extra Z bosons (would contribute to radiative correction R

V)

0.99990(60)

2460 GeV/cZm

( I.S. Towner & J.C. Hardy, Rep. Prog Phys. 73 (2010) 046301 )

- correlation


Future: - further increase precision

- radiative correction RV theoretical calculations

- nuclear correction NS - C measts. for heavy isotopes + theoretical calculations

- precision measurements of t1/2, BR and QEC

- independent tests

- neutron decay

- T = 1/2 mirror nuclei

|Vud|


|Vud| = 0.9719(17)

• Significant room for improvement with e.g. 3H, 17F, 19Ne, 33Cl, and 35Ar :

O. Naviliat-Cuncic &N.S. , Eur. Phys. J. A42 (2009) 327

Vud for relative

precision of 0.5 %

on a and/or A :

A requires trapped polarized nuclei !

2 0 00

2 2

1 2

= (1 )

A

V

mirror

VF ud R

f

fFt Ft Ft

K

G V

accuracy of 0.1 % to 0.4 % for mirror nuclei up to 41Sc

N.S., I.S.Towner et al., Phys. Rev. 78 (2008) 0555501

O. Naviliat-Cuncic & N.S. , Phys. Rev. Lett. 102 (2009) 142302

requires(Ft ) ~ 5 x 10-4

i.e. factor 2 -10

better

Note:

|Vud| (0+ 0+) = 0.97425 0.00022

(17F, 19Ne, 21Na, 29P, 35Ar and 37K)


38mK – A. Gorelov, J.A. Behr et al., PRL 94 (2005) 142501 – MOT

21Na – P. Vetter, S.J. Freedman et al., PR C 77 (2008) 035502 – MOT

6He – O. Naviliat-Cuncic et al., PRL 101 (2008) 212504 – Paul trap

35Ar – N. Severijns et al., NIM B 266 (2008) 4515 – Penning trap

21Na, 19Ne, … – K. Jungmann et al., NIM B 204 (2003) 532 – MOT

0.9981 0.0030 0.00 ( 1)34stat syst SMaa

( 0.5587(20.5502 0.0038 0.0046 7))stat sys St Maa

Recent and ongoing - corr. experiments with nuclei

04/21/23 N. Severijns, eurorib'10 conferenc

e - June 6-10, 2010

27

relative contributions to error barsof Ft values for mirror nuclei

Q value

branching

half-life

04/21/23

230245

320


04/21/23

Complementarity of beta decay RHC results and collider results,in general LRS models

RL = VudR / Vud

LRL = gR / gL

PDG (D0 exp.)

PDG (CDF exp.)

shaded areasare excluded


Nathal Severijns Kath. Universiteit Leuven, Belgium

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