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New Instruments for Neutrino Relics and Mass CERN, 8 December 2008
Orbital Electron-Capture Decay of Stored and Cooled Hydrogen-like Ions in the Experimental Storage Ring, ESR Christophor Kozhuharov, GSI Darmstadt Outline: Motivation Production, separation, storage, cooling, and nondestructive detecting of highly-charged radioactive ions at the FRS-ESR complex Two-body electron-capture decay of highly-charged ions. Single-ion decay spectroscopy Experimental results for EC of H-like 140Pr and 142Pm ions Some hypotheses on the observed non-exponential decay
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FRS/ESR Mass-and-Lifetime Collaboration
G. Audi, K. Beckert, P. Beller†, F. Bosch, D. Boutin, C. Brandau, Th. Bürvenich, L. Chen, I. Cullen, Ch. Dimopoulou, H. Essel, B. Fabian, Th. Faestermann, B. Franczak, B. Franzke, H. Geissel, E. Haettner, M. Hausmann, S. Hess, P. Kienle, O. Klepper, H.-J. Kluge, C. Kozhuharov, R. Knöbel, J. Kurcewicz, S.A. Litvinov, Yu. A. Litvinov, Z. Liu, L. Maier, M. Mazzocco, F. Montes, A. Musumarra, G. Münzenberg, S. Nakajima, C. Nociforo, F. Nolden, Yu. N. Novikov, T. Ohtsubo, A. Ozawa, Z. Patyk, B. Pfeiffer, W. R. Plass, Z. Podolyak, M. Portillo, A. Prochazka, R. Reuschl, H. Schatz, Ch. Scheidenberger, M. Shindo, V. Shishkin, U. Spillmann, M. Steck, Th. Stöhlker, K. Sümmerer, B. Sun, K. Suzuki, K. Takahashi, S. Torilov, M. B. Trzhaskovskaya, S. Typel, D. J. Vieira, G. Vorobjev, P.M. Walker, H. Weick, S. Williams, M. Winkler, N. Winckler, D. Winters, H. Wollnik, T. Yamaguchi 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Bound-State β-Decay M. Jung et al. Phys. Rev. Lett. 69 (1992) 2164
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Two-body β-decay of highly-charged ions
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Secondary Beams of Short-Lived Nuclei
Storage Ring ESR Linear Accelerator UNILAC Fragment Separator FRS Heavy-Ion Synchrotron SIS Production target 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Production & Separation of Exotic Nuclei
Highly-Charged Ions In-Flight separation Cocktail or one single nuclear species ≈ 600 MeV/u primary beams 400 MeV/u stored beams: fragments e.c. 140Pr, 142Pm, 205Hg, 207Tl, 206Tl, 122I
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Experimental Storage Ring, ESR: 108.4 m, 10-11 mbar
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Stochastic cooling at the ESR
Combiner Station Long. Pick-up Transv. Pick-up Long. Kicker Transv. Kicker ESR storage ring Stochastic cooling is particularly efficient for hot ion beams (Fixed energy: 400 MeV/u) 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Electron cooling: G. Budker, 1967 Novosibirsk
Cooling, i.e. enhancing the phase space density at constant beam velocities Electron cooling: G. Budker, 1967 Novosibirsk The momentum exchange of the ions with the cold collinear e- beam leads to an excellent emittance 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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'Phase transition' to a linear ion chain
ESR circumference ≈ 104 cm At mean distances of about 10 cm and larger the intra-beam-scattering disappears. For 1000 stored ions, the mean distance amounts to about 10 cm. M. Steck et al., PRL 77, 3803 (1996) 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Recording the Schottky-noise
Real time analyzer Sony-Tektronix 3066 ____________________________ 128 msec → FFT 64 msec_____________________
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SMS 4 particles with different m/q time
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Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
SMS Sin(w1) Sin(w2) Sin(w3) Sin(w4) Fast Fourier Transform w1 w2 w3 w4 time 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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300 kHz / 60 MHz Schottky TCAP
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Orbital EC-experiments, decay schemes
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Well-defined quantum states for parent and daughter ions
I Well-defined states: → bare, 1, 2.. e- II Quasi 'free': → storage ring/ trap III Time-resolved decay: → single ions IV Correlated decay: → change of mass 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
Cooling at ESR David Boutin, PhD Thesis, Univ. Giessen, 2005 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
Two-body beta decay f scales as m/q q does not change for the two-body β decay f changes only if the mass changes, or if the B-field changes. 260 Hz 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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EC in Hydrogen-like Ions
Expectations: lb+/lEC (neutral atom) ≈ 1 lEC(H-like)/lEC(He-like) ≈ 0.5 FRS-ESR Experiment l(neutral) = (1) s-1 G.Audi et al., NPA729 (2003) 3 lb+(bare) = (8) s-1 (decay of 140Pr59+) lEC(H-like) = (6) s-1 (decay of 140Pr58+) lEC(He-like) = (7) s-1 (decay of 140Pr57+) lEC(H-like)/lEC(He-like) = 1.49(8) Yu. A. Litvinov et al., PRL 99, (2007) 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Electron Capture in Hydrogen-like Ions
Gamow-Teller transition 1+ 0+ S. Typel and L. Grigorenko µ = µN (calc.) Theory: Z. Patyk et al., PR C77, (2008) The H-like ion decays by 20% faster than the neutral atom! Probability of EC Decay Neutral 140Pr: P = 2.381 He-like 140Pr: P = 2 λ(H)/λ(He) = (2I+1)/(2F+1) H-like 140Pr: P = 3 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Nuclear Decay of Stored Single Ions
Time/channel = 30 sec. 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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We restrict the analysis to 1 to 3 injected ions:
1. The Schottky areas have a very large variance. 2. The variance of the amplitudes is larger than the step 3→4. 3. Problem of 'delayed cooling' Daughter Amplitude Amplitude Mother N. Winckler Amplitude distributions corresponding to 1,2,3-particles; 1 frame = 128 msec. The final data occur within msec. in both the computer as well as in the ‘manual’ evaluations; In all cases the ‘appearance’ time has been taken into account.
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Examples of measured time-frequency traces
↕ Time/ch. = 640 msec Time/ch. = 640 ms 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
↕ Time/ch. = 64 msec 2 140Pr58+ 1 140Pr58+ 1 140Ce58+ 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Properties of measured time↔frequency traces
1. Continuous observation 2. Parent/daughter correlation 3. Detection of all EC decays 4. Delay between decay and "appearance" due to cooling 5. 140Pr: ER = 44 eV Delay: 900 (300) msec 142Pm: ER = 90 eV Delay: 1400 (400) msec from measured frequency: → p transformed to n (hadronic vertex) → bound e- annihilated (leptonic vertex) → ν created at td as νe = a │ν1 > + b ν2 > if conservation of lepton number holds 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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2. Experimental results for EC of H-like ions: 140Pr58+
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Fast Fourier Transform of the data of 1.+2. run
Frequency peak at f = Hz Yu. A. Litvinov et al., Phys. Lett. B 664, 124 (2008) 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
140Pr58+ all runs: 2650 EC-decays from 7102 injections 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
142Pm60+: 2740 EC decays from 7011 injections 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
142Pm60+: zoom on the first 33 s after injection 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Fits with pure exponential (1) and superimposed oscillation (2)
dNEC (t)/dt = N0 exp {- λt} λEC ; λ = λβ+ + λEC + λloss (1) dNEC (t)/dt = N0 exp {- λt} λEC(t); λEC(t) = λEC [1+a cos(ωt+φ)] (2) T = 7.06 (8) s φ = 0.4 (4) a = 0.18 (3) T = 7.10 (22) s φ = (4) a = 0.23 (4) 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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3. Some hypotheses on the non-exponential decays
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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EC in H-like ions for nuclear g.s. → g.s. transitions
Decay identified by correlated change of atomic mass at time td Different delay due to emission characteristics of the neutrino Small total line width(s) Ћ / ΔtObs (≈ 0.1 s ) ≈ eV >> Ћ / T (≈ 7 s) ≈ eV No third particle involved → daughter nucleus and neutrino entangled by momentum- and energy conservation → EPR scenario 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Quantum beats from the hyperfine states ?
Coherent excitation of the 1s hyperfine states F =1/2 & F=3/ Beat period T = h/ΔE ≈ s µ = µN (calc.) Decay can occur only from the F=1/2 (ground) state Periodic spin flip to "sterile" F=3/2 ? → λEC reduced 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
"Classical" quantum beats Coherent excitation of an electron in two quantum states, separated by ΔE at time t0, e.g. 3P0 and 3P2 Observation of the decay photon(s) as a function of (t-t0) Exponential decay modulated by cos(ΔE / Ћ (t-t0)) - Δτ - if Δτ<< T = h/ΔE → no information whether E1 or E2 "which path"? addition of amplitudes Chow et al., PR A11(1975) 1380 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Beats due to neutrino being not a mass eigenstate?
The electron neutrino appears as coherent superposition of mass eigenstates The recoils appear as coherent superpositions of states entangled with the electron neutrino mass eigenstates by momentum- and energy conservation M + p12/2M + E1 = E M + p22/2M + E2 = E "Asymptotic" conservation of E, p E, p = 0 (c.m.) νe (mi, pi, Ei) M, pi2/2M m12 – m22 = Δ2m = 8 · 10-5 eV2 E1 – E2 = ΔEν ΔEν ≈ Δ2m/2M = 3.1 · eV Δpν ≈ - Δ2m/ 2 <pν> = 2.0 · eV 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
cos (ΔE/ћ t) with Tlab = h γ / ΔE ≈ 7s a) M = 140 amu, Eν = 3.39 MeV (Pr) b) M = 142 amu, Eν = 4.87 MeV (Pm) M =141 amu, γ = 1.43, Δ2m12 = 8 · 10-5 eV2 ΔE = hγ / Tlab = 8.4 · eV ΔEν = Δ2m /2 M = 3.1 · eV 8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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New Experiment on 118Sb (122I)
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Decay scheme of 118Sb Experiment was scheduled:
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Decay scheme of 122I
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Correlations: 10.808 injections ~1080 EC-decays
Decay statistics Correlations: injections ~1080 EC-decays Many ions: 5718 injections ~5000 EC-decays Analyzed : I. About 60% of the overall data II. About 20% of the overall data Automatic analysis is delayed
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For the two-body EC decays of H-like 140Pr and 142Pm periodic modulations according to e –λt [1+a cos(ωt+φ)] with Tlab = 2π/ω = 7s, a ≈ 0.20 (4) were found Statistical fluctuations are not excluded on a c.l. > 3.5 σ Oscillation period T proportional to nuclear mass M ?
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Only a few out of many remaining questions
1. Are the oscillations real ? → still modest statistics 2. Can the coherence be maintained over some 10 s keeping in mind the confinement in an electromagnetic potential, the continuous interaction, and the continuous observation ?? How can we improve the statistics, what other systems can we probe, what other ESR settings can we use?
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