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b +. n e. Fundamental interaction studies with radioactive nuclei. eurorib’10 conference Lamoura, 6-10 June 2010. Nathal Severijns Kath. Universiteit Leuven, Belgium. 1. searches for exotic weak currents (non V-A) - tensor currents - scalar currents - right-handed currents
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b+ ne Fundamental interaction studies with radioactive nuclei eurorib’10 conference Lamoura, 6-10 June 2010 Nathal Severijns Kath. Universiteit Leuven, Belgium N. 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. Vudand CVC 3. atomic parity violation - Fr (Legnaro) - Ra, … (KVI-Groningen) N. 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. Vudand 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 N. Severijns, eurorib'10 conference - June 6-10, 2010
e+ nucleus q ne , J Correlation measurements in nuclear decay - correlation asymmetry most experiments determine: asymmetry Fierz interference term ( b 0 in standard model ) J.D. Jackson et al., Nucl. Phys. 4 (1957) 206 N. Severijns, eurorib'10 conference - June 6-10, 2010
e+ nucleus q ne -correlation (assuming maximal P-violation and T-invariance for V and A interactions) recoil corr. (induced form factors) 10-3 ; radiative corrections 10-4 N. Severijns, eurorib'10 conference - June 6-10, 2010
TRINAT MOT trap at TRIUMF-ISAC (J. Behr et al.) Traps: ideal source - sample is isotopically pure - localized in small volume - atoms decay at rest - negligible source scattering - potential for polarized sample search for exotic scalar couplings with 38mK superallowed 0+ 0+ pure Fermi transition (t1/2 = 0.95 s) N. Severijns, eurorib'10 conference - June 6-10, 2010
A. Gorelov, J. Behr et al., PRL 94 (2005) 142501
b-n angular correlation for Magneto-Optically Trapped 21Na P. A. Vetter, S. J. Freedman et al., Phys. Rev. C77 (2008) 035502 Recoil-ion TOF aexp = 0.5502 ± 0.0038 ± 0.0046 aSM = 0.5587 ± 0.0027 Result:
LPC-Caen Paul trap at GANIL (O. Naviliat-Cuncic et al.) GT O. Naviliat et al.
LPC-Caen Paul trap at GANIL (O. Naviliat-Cuncic et al.) (tensor) (axial-vector) N. Severijns, eurorib'10 conference - June 6-10, 2010 10
WITCH Penning trap at ISOLDE - search for scalar weak currents First First recoil ion spectrum 124Sn recoils Preliminary pulse height distribution Retardation potential (V) K.U.Leuven, Uni. Munster, ISOLDE, GSI, NPI Rez-Prague (N.Severijns et al.) • Goal : measure bn correlation for 35Ar with (a/a)stat 0.5 % • Detect recoiling ions in singles (MCP) • Determine ion energies with retardation potential MCP signal proof of principle demonstrated ions ’s V.Yu. Kozlov et al., NIM B 266 (2008) 4515 M. Beck et al., NIM A 503 (2003) 567 IS433-experiment N. Severijns, eurorib'10 conference - June 6-10, 2010
KVI-Groningen N. Severijns, eurorib'10 conference - June 6-10, 2010
J asymmetry for a pure Gamow-Teller transition : 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 ) N. Severijns, eurorib'10 conference - June 6-10, 2010
Recent asymmetry measurements at Leuven and ISOLDE (IS431) with 60Co, 67Cu and114In region analysed no energy dependence left corrections OK see talk of Frederik Wauters F. Wauters et al., NIM A 609 (2009) 156, PR C 80 (2009) 062501 PR C submitted N. Severijns, eurorib'10 conference - June 6-10, 2010
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) N. Severijns, eurorib'10 conference - June 6-10, 2010
J polarized atoms in a MOT Bneutrino asymmetry parameter for 37K asymmetry 5 % precision very difficult to determine nuclear polarization precisely ! TRINAT MOT trap @ TRIUMF 37K – D. Melconian, J.A. Behr et al., Phys. Lett. B 649 (2007) 370 N. Severijns, eurorib'10 conference - June 6-10, 2010
Polarization by optical pumping and determination of nuclear polarization via photoionization in a MOT D. Melconian, J.A. Behr et al., Phys. Lett. B 649 (2007) 370 37K 80Rb J.R.A. Pitcairn, J.A. Behr et al., Phys. Rev. C79 (2009) 015501 N. Severijns, eurorib'10 conference - June 6-10, 2010
Asymmetry parameter of recoil ions with 80Rb in MOT J. Behr et al. - TRIUMF interpretation difficult due to recoil terms (quark bound in nucleon ! 0.1 – 1 % effect) 80Rb – J.R.A. Pitcairn, J.A. Behr et al., PR C 79 (2009) 015501
Longitudinal polarization of positrons emitted by polarized nuclei with : P- (P+) the particle longitudinal polarization for ’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 N. Severijns, eurorib'10 conference - June 6-10, 2010
Results : signal MW2 > 320 GeV/c2 (90 % C.L.) 1) N. Severijns et al., PRL 70 (1993) 4047, 73 (1994) 611 2) M. Allet et al., Phys. Lett. B363 (1996) 139 3) E. Thomas et al., Nucl. Phys. A694 (2001) 559 4) N. Severijns et al., Nucl. Phys. A629 (1998) 423c for Pnucl = 0.80 & 1% precision on P- /P+ N. Severijns, eurorib'10 conference - June 6-10, 2010
recent review: I.S. Towner & J.C. Hardy Rep. Prog. Phys. 73 (2010) 046301 Vudand CVC (masses, decays theory, …) from K decays 0.99990(60) stronglimits on physics beyond Standard Model e.g. - scalar currents - right-handed currents N. Severijns, eurorib'10 conference - June 6-10, 2010
0.99990(60) stronglimits on physics beyond Standard Model e.g. - scalar currents - right-handed currents : = 0.000 05(30) - extra Z bosons (would contribute to radiative correction RV) - correlation ( I.S. Towner & J.C. Hardy, Rep. Prog Phys. 73 (2010) 046301 ) N. Severijns, eurorib'10 conference - June 6-10, 2010
Future: - further increaseprecision - 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| N. Severijns, eurorib'10 conference - June 6-10, 2010
(17F, 19Ne, 21Na, 29P, 35Ar and 37K) 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 |Vud| = 0.9719(17) O. Naviliat-Cuncic & N.S. , Phys. Rev. Lett. 102 (2009) 142302 • Significant room for improvement with e.g. 3H, 17F, 19Ne, 33Cl, and 35Ar : Vud for relative precision of 0.5 % on a and/or A : A requires trapped polarized nuclei ! requires (Ft ) ~ 5 x 10-4 i.e. factor 2 -10 better Note: |Vud| (0+ 0+) = 0.97425 0.00022 O. Naviliat-Cuncic &N.S. , Eur. Phys. J. A42 (2009) 327 N. Severijns, eurorib'10 conference - June 6-10, 2010
Recent and ongoing - corr. experiments with nuclei 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 N. Severijns, eurorib'10 conference - June 6-10, 2010
relative contributions to error bars of Ft values for mirror nuclei half-life Q value branching N. Severijns, eurorib'10 conference - June 6-10, 2010
230 245 320 N. Severijns, eurorib'10 conference - June 6-10, 2010
Complementarity of beta decay RHC results and collider results, in general LRS models PDG (CDF exp.) PDG (D0 exp.) RL = gR / gL RL = VudR / VudL shaded areas are excluded N. Severijns, eurorib'10 conference - June 6-10, 2010