The Weak Interaction in Low Energy Nuclear Physics

The Weak Interaction in Low Energy Nuclear Physics ARIS-2014 Tokio, June 1 -6, 2014 b+ Nathal Severijns ne KU Leuven, Belgium

Overview e+ - recent / ongoing achievements q - APV and EDM nucleus ne - Vud and unitarity / Ft-values - exotic weak currents (scalar, tensor, V+A) (selected experiments showing diversity in techniques used) - new vistas and prospects - conclusion and outlook for this field in the LHC era

1. Atomic Parity Violation & Electric Dipole Moments Atomic Parity Violation probing sin 2 W at atomic energies (test Standard Model) 206 Fr @ TRIUMF, LNL 223 Ra @ KVI enhancement factors of ~15 and ~50 compared to 133 Cs case (Wiemann et al. ) Electric Dipole Moments matter/anti-matter difference in the Universe 225 Ra @ ANL and KVI 223 Rn @ TRIUMF 129 Xe @ Tokyo and TUM sensitivity to EDM enhanced by (by several 100 to few 1000 times): - near degeneracy of atomic levels - octupole deformation of nuclear charge distribution

2. Vud quark mixing matrix element & CKM unitarity from experiment nucleus dependent corrections nucleus independent |Vud| = 0. 97425(22) Hardy & Towner, PR C 79 (2009) 055502 |Vus| = 0. 22564(53) Dowdall et al. , Phys. Rev. D 88, 074504 (2013) = 3071. 81(83) s Towner & Hardy, Rep. Prog Phys. 73 (2010) 046301

prospects - 1 1. superallowed Fermi transitions - new data for 0+ pure Fermi transitions - testing isospin corrections C - nucleus-independent radiative correction R 2. corrected Ft values of T = 1/2 mirror transitions and neutron decay could contribute as well N. S. , I. S. Towner et al. , Phys. Rev. C 78(2008) 055501 O. Naviliat-Cuncic & N. S. , PRL 102 (2009) 142302

prospects - 2 2 a. Neutron decay - no nuclear structure related corrections - issues of lifetime and asymmetry parameter first have to be resolved 2 b. T = 1/2 mirror transitions could contribute as well - additional tests for isospin corrections C - provide additional value for Vud (set of consistent data needed) good cases: e. g. 19 Ne: 35 Ar - β -corr. measurement performed with LPCTrap : β -corr. measurement performed with LPCTrap; β-asym. measurement in preparation (if A/A = 0. 5% Vud = 0. 0004) requires measurements of QEC, t 1/2 and BR leading to Ft values for mirror transitions N. S. & O. Naviliat-Cuncic, Physica Scripta T 152 (2013) 014018

3. Exotic weak currents (scalar, tensor, V+A) 1. correlation exp. Fierz term !!! for pure transitions weak interaction results are independent of nuclear matrix elements !!!

scalar - TRINAT MOT trap at TRIUMF-ISAC – 38 m. K search for scalar couplings superallowed 0+ pure Fermi transition (t 1/2 = 0. 95 s) A. Gorelov, J. Behr et al. , Phys. Rev. Lett. 94 (2005) 142501 TOF

ongoing experiments in search for scalar weak currents: - LPCTrap-GANIL (Paul): - WITCH-ISOLDE (Penning): - Jerusalem (MOT): - Tamu. Trap , Texas (Paul): 35 Ar scalar: a = -1 WITCH in m eli r p ary 19 Ne, 35 Ar PS 1 -A 065 – Delahaye 35 Ar 19 Ne 32 Ar (T=2, βp) Da/a ~ 0. 3% 35 Ar (analysis in progress) ary in vector: a = +1 p poster D. Zakoucky PS 1 -A 061 m eli r LPCTrap - GANIL

Limits on scalar currents = 3071. 81(83) s 38 m. K: Towner & Hardy, Rep. Prog Phys. 73 (2010) 046301 Gorelov, Behr et al. , PRL 94 (2005) 142501

Tensor - LPCTrap @ GANIL - 6 He / 35 Ar 2006 (6 He): aβν = − 0. 3335(73)stat(75)syst X. Fléchard et al. , J. Phys. G 38 (2011) 055101 Li 2+ Li 3+ 6 He 2010 Da/a ~ 0. 5 % (stat) (analysis in progress) charge-state distribution and comparison to atomic theory: C. Couratin et al. , PRL 108 (2012) 243201

Tensor - 6 He MOT Trap setup @ Univ. Washington, Seattle P. Mueller, A. Garcia, et al. 1083 nm 6 He Trap/Detector Chamber er ll e • • • u M – RF discharge -> metastable He* Laser cooling @ 1083 nm Timeline: - 6 He produced and trapped - first data run in August 2013 --> 1 % measurement -B S 2 P 05 0 - 0. 1 % measurement by 2015 6 He Trapping Rates @ CENPA: @ source: 5 x 109 s-1 ; capt. efficiency = 2 x 10 -7; @ trap: 1000 s-1 Trap-to-trap transfer: > 60% efficiency, ~15 ms A. Knecht et al. , NIM A 660 (2011) 43, Phys. Rev. C 86 (2012) 035506 & ar. Xiv: 1208. 6433 v 2 [nucl-ex]

O. Aviv et al. , J. Phys. : Conf. Ser. 337, 012020 (2012) 3/19/2018 13 N. Severijns, CGS 14 conference - Aug. 28 -

Tensor - - - Correlation in Paul trapped 8 Li Ions G. Savard et al. (ANL, Mc. Gill, LLNL, Univ. Chicago, … ) aβν = − 0. 3307 (60)stat (67)sys G. Li, G. Savard et al. , PRL 110 (2013) 082502 data with ~20 times more statistics + lower systematics to be published 1% or better Poster PS 2 -B 004 – Perez Galvan

Tensor - β asymmetry – Leuven / ISOLDE / Prague F. Wauters et al. , NIM A 609 (2009) 156 region analysed Aexp (60 Co) = - 1. 014 (12)stat (16)syst F. Wauters et al. , Phys. Rev. C 82 (2010) 055502 Aexp (114 In) = - 0. 990 (10)stat (10)syst F. Wauters et al. , Phys. Rev. C 80 (2009) 062501(R) F. Wauters et al. , Phys. Aexp (67 Cu) = 0. 587(8)stat (12)syst Rev. C 80 (2009) 062501(R) G. Soti et al. , submitted to PR C

Constraints on tensor type weak couplings a(6 He) - - A(60 Co) (8 Li) C. Johnston et al. , PR 132 (1963) 1149 A(60 Co) A(67 Cu) F. Wauters, N. S. et al. , PR C 82 (2010) 055502 - - (8 Li) G. Li, G. Savard et al. , PRL 110 (2013) 082502 A(67 Cu) G. Soti, N. S. et al. , (2013) submitted a(6 He)

New vistas and prospects in the LHC era - 1 - new generation of trap-based experiments towards 0. 1% precision level - precise -spectrum shape measurements (Leuven-Krakow, MSU-NSCL, LPC Caen, … ) b. Fierz : scalar / tensor weak currents b. WM : weak magnetism (Standard Model term) - induced by strong interaction because decaying quark is not free but bound in a nucleon; - is to be known better when reaching sub-percent precisions Note the different energy dependence of both effects !!

mini. BETA spectrometer (Leuven / Krakow) multi-wire drift chamber scintillator (later DSSDD) poster P. Finlay PS 2 -CO 23

New vistas and prospects in the LHC era - 2 - perform more measurements with polarized nuclei access to A and other correlations involving nuclear spin Beta and recoil asymmetries w. r. t. nuclear spin - MOT trap : optical pumping in the trap, in magnetic holding field TRIUMF: 80 Rb, 37 K Jerusalem-Tel Aviv-Rehovot: 19 Ne ULiège-KU Leuven: - 35 Ar collinear laser optical pumping NSCL-BECOLA, ISOLDE-COLLAPS: 21 Na, 23 Mg, 35 Ar, 37 K

Precision measurements in nuclear/neutron decay in the LHC era 90 % CL nuclear and neutron decay, pion decay O. Naviliat-Cuncic and M. Gonzalez-Alonso Annalen der Physik (2013) in print. V. Cirigliano, et al. , J. High. Energ. Phys. 1302 (2013) 046 90 % CL limits on scalar/tensor couplings obtained by CMS collaboration in pp e + MET + X channel - S. Chatrchyan et al. (CMS Collab. ) J. High. Energ. Phys. 1208 (2012) 023; - CERN Rep. nr. CMS-PAS-EXO-12 -060 (2013)

Conclusions and Outlook - pure Fermi transition Ft-values, and possibly neutron decay parameters and correlation measurements in mirror transitions contribute to further improving precision of Vud mixing matrix element; - - correlation and asymmetry measurements + Ft-values improved limits on scalar and tensor type weak currents; - additional observable: beta-spectrum shape scalar/tensor currents and weak magnetism - searches for new physics (bosons) at low energies remain competitive with direct searches at LHC when concentrating on Fierz term and Vud - many experiments ongoing or planned / in preparation

Contributed talks and Posters EDM - APV: Par. 1 C – Sato PS 1 -A 064 – Ohtomo PS 1 -A 066 – Ohtomo PS 1 -A 067 – Mueller PS 2 -B 001 – Kawamura PS 2 -B 002 – Teruya PS 2 -B 003 – Inoue PS 2 -C 020 – Harada (APV) ββ-decay: Par. 1 C – Hinohara PS 1 -A 064 – Ringle PS 2 -B 006 – Yoshinaga Superallowed Fermi: Par. 1 C – Laffoley Par. 1 C – Park PS 1 -A 062 – Blank PS 1 -A 063 – Nishimura β-decay correlations: and β-spectrum shape PS 1 -A 061 – Zakoucky PS 1 -A 065 – Delahaye PS 2 -B 004 – Perez Galvan PS 2 -B 005 – Mueller PS 2 -C 023 – Finlay (spectrum shape)

Backup slides

Ion/atom correlation measurements Most precise traps for - correlation measurements Particle traps: ideal sources - sample is isotopically pure - localized in a small volume - atoms decay at rest - detection of recoil ion - negligible source scattering - potential for polarized sample MOT Penning Paul

Overview of - correlation projects a = − 0. 3307(60)(67) N. S. & O. Naviliat-Cuncic, Physica Scripta T 152 (2013) 014018

MOT trap for radioactive Ne isotopes G. Ron et al. (Hebrew Univ. , Weizmann Inst. and SOREQ – Israel) 17, 18, 19, 23, 24 Ne - p/d accelerator (5 m. A/up to 40 Me. V) - neutron generator Zeeman slower G. Ron, priv. comm. double-trap MOT concept (similar to TRINAT)

WITCH @ ISOLDE - 35 Ar - scalar (KU Leuven, Univ. Munster, ISOLDE, NPI Rez-Prague, LPC-Caen) Goal : determine correlation for 35 Ar with ( a/a)stat 0. 5 % measure energy spectrum of recoiling ions with a retardation spectrometer scalar: a = -1 ary in lim re p vector: a = +1 poster by Paul Finlay M. Beck et al. , Eur. Phys. J. A 47 (2011) 45 M. Tandecki et al. , NIM A 629 (2011) 396 S. Van Gorp et al. , NIM A 638 (2011) 192 3/19/2018