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)
04/21/23 3N. 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
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
04/21/23 4N. Severijns, eurorib'10 conference - June 6-10, 2010
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
04/21/23 5N. Severijns, eurorib'10 conference - June 6-10, 2010
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
04/21/23 6N. Severijns, eurorib'10 conference - June 6-10, 2010
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)
04/21/23 11N. Severijns, eurorib'10 conference - June 6-10, 2010
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
04/21/23 13N. 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
04/21/23 14N. Severijns, eurorib'10 conference - June 6-10, 2010
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)
04/21/23 16N. Severijns, eurorib'10 conference - June 6-10, 2010
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
04/21/23 17N. Severijns, eurorib'10 conference - June 6-10, 2010
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.)
20N. Severijns, eurorib'10 conference - June 6-10, 2010
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
04/21/23 22N. Severijns, eurorib'10 conference - June 6-10, 2010
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
04/21/23 23N. Severijns, eurorib'10 conference - June 6-10, 2010
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|
04/21/23 24N. Severijns, eurorib'10 conference - June 6-10, 2010
|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)
04/21/23 25N. Severijns, eurorib'10 conference - June 6-10, 2010
04/21/23 26N. Severijns, eurorib'10 conference - June 6-10, 2010
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
28N. Severijns, eurorib'10 conference - June 6-10, 2010
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
29N. Severijns, eurorib'10 conference - June 6-10, 2010