Atomic PNC, a personal view in 2014 Luis A. Orozco Fundamental Symmetry Tests with Rare Isotopes Amherst Center for Fundamental Interactions University of Massachusetts Amherst October, 2014
Thanks to: John Behr (TRIUMF) Dima Budker (Berkeley, Mainz) Roberto Calabrese (Ferrara) Sidney Cahn (Yale) David DeMille (Yale) Andrei Derevianko (Reno) Victor Flambaum (New South Wales) Gerald Gwinner (Manitoba) Klaus Jungmann (KVI) Shelley Page (Manitoba) Mariana Safranova (Delaware) Fr work supported by: NRC, TRIUMF, and NSERC from Canada, DOE, and NSF from the USA, and CONACYT from Mexico.
H PV = G F ( κ 1 i γ 5 − κ nsd , i σ n ⋅ α ) δ ( r ) 2 NSD NSI H PV H PV Nuclear spin dependent Nuclear spin independent interaction: Interaction: • Only from valence nucleons. • Coherent over all • Measurement increases as Z 8/3 nucleons. • Main contribution from anapole • Measurement increases moment for heavy nuclei. as Z 3
Gwinner
Safranova
Gwinner
Page
Constraints on couplings PDG 2013 Page
Safranova
Dzuba et al, PRL, 109, 203003 (2012) Safranova/Flambaum
Weak charge of 133 Cs 1.5 σ agreement with the Standard Model Experiment: Wood et al . (1997); Bennett and Wieman (1999) (Boulder group) Theory: V. A. Dzuba, J. C. Berengut, V.V. Flambaum, and B. Roberts, (2012) 11 Derevianko
Implications: extra Z bosons (Z’) Specific example: Z’ χ in SO(10) GUT result implies: LHC discovery reach: 5 TeV full luminosity Also implications for Dark Z (Marciano) Derevianko/Flambaum
The Anapole Moment History 1958 Zel’dovich, Vaks 1980 Khriplovich, Flambaum 1984 Khriplovich, Flambaum, Shuskov 1995 Fortson (Seattle) bound from an experiment Thallium 1997 Wieman (Boulder) 15% measurement from an experiment Cesium
isoscalar isovector Does weak N-N interaction change in heavy nuclei? Behr
210 Fr 209 Fr Constraints of couplings (10 7 ) from future measurements of two francium isotopes (even and odd isotopes) based on the calculations of Flambaum and Murray.
Gwinner
Yb PV Amplitude Results (Berkeley) ζ / β =39(4) stat. (5) syst. mV/cm ⇒ | ζ |=(8.7±1.4) × 10 -10 ea 0 Accuracy is affected by HV-amplifier noise, fluctuations of stray fields, and laser drifts → improved for the next phase Budker
Parity Nonconservation in Dy Experiment (1997): • |H w | = 2.3 ± 2.9 (statistical) ± 0.7 (systematic) Hz • A. T. Nguyen et. al . Phys. Rev. A 56 , 3453 (1997) Theory (2010): • H w ≈ 2 Hz • V. Dzuba and V. Flambaum (http://arxiv.org/abs/1001.1184) 18 Budker
Atomic Parity Non-Conservation in a single Barium Ion Blinov and Fortson (U. Washington).
Single ion work in Ra + at KVI following a proposal by Fortson Jungmann
Jungmann
Using molecules to get at NSD-PNC Diatomic molecules systematically have close rotation+hyperfine levels of opposite parity--B-field tuning can give Δ E ~ 10 -11 eV. [ Sushkov, Flambaum, Sov. Phys. JETP 48, 608 (1978), Flambaum, Khriplovich, Phys. Lett. A 110, 121 (1985) Kozlov, Labzowsky, & Mitruschenkov, JETP 73 , 415 (1991)], D. DeMille, S.B. Cahn, D. Murphree, D.A. Rahmlow, and M.G. Kozlov Phys. Rev. Lett. 100, 023003 (2008)] Cahn
FrPNC Collaboration (Fall 2014) Seth Aubin; College of William and Mary, USA. John A. Behr, Matt R. Pearson, Michael Tandecki; TRIUMF, Canada. Victor V. Flambaum; University of New South Wales, Australia. Eduardo Gómez; Universidad Autónoma de San Luis Potosí, México. Gerald Gwinner SPOEKESPERSON Robert Collister, Kyle Shiells Michael Tandecki; University of Manitoba, Canada. Dan Melconian; Texas A&M, USA. Luis A. Orozco, Jiehang Zhang, Michael Kossin; University of Maryland, USA. Gene D. Sprouse; SUNY Stony Brook, USA. Yanting Zhao; Shanxi University, Taijuan, China.
FrPNC Commissioned in 2012 the trapping apparatus at TRIUMF. NEXT (December 2014 run): Commission Science chamber: transfer Fr from capture chamber to science chamber. Measure ground state HF splitting directly with microwaves and observe Stark mixing. TO DO list: Measurement of PNC in the hyperfine transition (spin dependent) of the ground state and extract anapole moments of a chain of Fr isotopes . Measure of Optical PNC (spin independent) and extract the weak charge.
Spectroscopy studies of francium Ideal cold sample of trapped atoms (no Doppler broadening) Quantitative comparisons to ab initio calculations. Energy levels Excited state lifetimes (transition matrix elements) Hyperfine splittings (wavefunctions at the nucleus) Nuclear structure studies with atomic spectroscopy (magnetization).
8s lifetime comparison with theory a) Safronova et.al. b) Dzuba et.al. c) Johnson et.al. d) Dzuba et.al. e) Marinescu et.al. f) Theodosiou et.al. g) Biemont et.al. h) Van Wijngaarden et.al. ±0.8%
HF Anomaly preliminary results Dashed: Magnetic Radius change equal to Charge Radius change Green: Nuclear Structure Theory Blue and Red: Measurements
Method 1.- Define handedness of the apparatus by the coordinate system ( iE RF × B M 1 ⋅ B DC ) 2.- Create superposition to interfere and enhance PNC signal: PC ± A E 1 PNC A total = A M 1 3.- Measure rate of transition through resonance fluorescence. 2 Rate ∝ A total 4.- Change handedness of apparatus 2 − A total 2 + − Signal ∝ A total 5.- Repeat. Expected signal with 450 V/m A E 1 � = 0.01 rad / s
Oscillations and sensitivity test M1 Rabi oscillations (50 Hz) with 10 5 Rb atoms in blue detuned (20 nm) dipole trap. Decoherence time 180 ms. While sitting at 37.5 ms, add a second microwave source with 10 4 attenuation, change of the phase and see the signal increase and decrease.
Signal Noise = 2 Ω E 1 Δ t N = 2 Number of atoms = N ~ 10 6 Ω E1 ~ 10 mrad Interaction time = Δτ ~ 0.1s
Schematic of the capture assembly
Fr beam onto Y foil
Commissioning of Capture: Sep., Dec. 2012 • Trapped atoms: > 2.5 × 10 6 ) • Efficiency ~ 0.5% • Trap lifetimes ~ 20s • Isotopes trapped 206, 207, 209, 213, 221. • Radioactive lifetime ( τ 1/2 = 50.5 s for 209 Fr)
Preparation of Science Chamber, commissioning in Dec 2014 Science Chamber Fr from capture chamber microwaves/ 506nm light
Precision tests of the weak interaction in atoms, they measure the weak charge and can give limits on the nucleon nucleon weak couplings. Experiments with trapped and cooled species starting (Fr, Ra + ) and proceeding (Yb, Dy, molecules). Many isotopes. FrPNC will benefit from the 10 8 demonstrated at TRIUMF, FRIB is looking very interesting.
THANKS!
Recommend
More recommend