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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 - PowerPoint PPT Presentation
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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
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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
UniS
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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
Two-body β-decay of highly-charged ions
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
Fragment Separator
FRS
Secondary Beams of Short-Lived Nuclei
Productiontarget
StorageRingESR
Heavy-IonSynchrotron
SIS
LinearAccelerator
UNILAC
Production & Separation of Exotic Nuclei
Highly-Charged IonsIn-Flight separation
Cocktail or one single nuclear species
≈ 600 MeV/u primary beams400 MeV/u stored beams: fragments e.c. 140Pr, 142Pm, 205Hg, 207Tl, 206Tl, 122I
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
Experimental Storage Ring, ESR: 108.4 m, 10-11 mbar
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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
Cooling, i.e. enhancing the phase space density at constant beam velocities
The momentum exchange of the ions with the cold collinear e- beam leads to
an excellent emittance
Electron cooling: G. Budker, 1967 Novosibirsk
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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.
'Phase transition' to a linear ion chain
M. Steck et al., PRL 77, 3803 (1996)
Electron cooler
G as-target
Q uadrupole-trip let
Septum -m agnet
D ipole m agnet
Fast kickerm agnet
RF-Acceleratingcavity
Hexapole-m agnets
From the FR S
Extraction
To the S IS
Q uadrupole-dublet
Schottky p ick-ups
Recording the Schottky-noise
0v
v
SchottkyP ick-ups
Stored ion beam
f ~ 2 M H z0
FFT
am plificationsum m ation
____________________________ 128 msec
→ FFT 64 msec_____________________
→ FFT
Real time analyzer Sony-Tektronix 3066
time
SMSSMS
4 particles with different m/q
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
Sin(1)
Sin(2)
Sin(3)
Sin(4)
1234time
Fast Fourier Transform
SMSSMS
0 1 0 . 0 2 0 . 0 3 0 . 0 4 0 . 0 5 0 . 0 6 0 . 0 7 0 . 0 8 0 . 00
5
1 0
8 0 . 0 9 0 . 0 1 0 0 . 0 1 1 0 . 0 1 2 0 . 0 1 3 0 . 0 1 4 0 . 0 1 5 0 . 0 1 6 0 . 0
1 6 0 . 0 1 7 0 . 0 1 8 0 . 0 1 9 0 . 0 2 0 0 . 0 2 1 0 . 0 2 2 0 . 0 2 3 0 . 0 2 4 0 . 0
240.0 250.0 260.0 270.0 280.0 290.0 300.0 310.0 320.0
know n m asses A q+X unknow n m asses
N um ber of channels 216
R ecord ing tim e 30 sec
188 78+Pt
0
5
10
0
5
10
0
5
10
Frequency / kHz
Inte
nsity
/ ar
b. u
nits
201 84+
194 81+Tl
182 76+Pt182 76+
182 76+
189 79+
Ir
O s
Po
Hg
189 79+Au
177 74+W
196 82+Bi
196 82+Pb
184 77+Pt
184 77+Ir198 83+Bi
191 80+Tl
191 80+Hg
194 81+Au
200 83+Bi
183 76+Ir
183 76+O s
195 81+Tl195 81+PbPb
188 78+ 178 74+Re
190 79+Au
197 82+Bi
197 82+Pb
185 77+Ir
185 77+Pt192 80+Tl
192 80+Hg
199 83+Bi187 78+Pt
187 78+Au
Pb
190 79+Hg
IrAu 181 75+
198 82+Pb
193 80+Tl
193 80+Hg
194 80+Tl194 80+
189 78+
Tl191 79+Hg
187 77+
199 82+ Pb
Hg
196 81+
204 84+
Pt
Pb
Pt Ir186 77+
Po
187 77+Au
BiPbPb
182 75+Ir
194 80+Hg 189 78+Au189 78+
201 83+Po
201 83+Bi184 76+
184 76+O s
191 79+Au
203 84+Po
186 77+Pt
186 77+Ir181 75+R e198 82+Bi
193 80+Pb199 82+
O s181 75+
200 82+Bi
195 80+Tl
197 81+Pb
197 81+Bi 192 79+Hg
192 79+Au
198 81+Bi
198 81+Pb193 79+Tl
193 79+Hg
188 77+Au 205 84+Po
200 82+Pb200 82+Po195 80+Pb
190 78+Hg
190 78+Au
185 76+Pt
202 83+Po
202 83+Bi 197 81+Tl198 81+Pb
188 77+Pt
A q+X
15
0m
,g
6
5+
Dy
150
65
+
Tb
143
6
2+
143
m,g
6
2+
Eu S
m
157
68+
Er
127
55+
Cs
157
6
8+T
m
173
7
5+
166
72
+1
66
72+
180
78
+P
t
Re
Hf
Ta
152
6
6+
152
6
6+
Ho
Dy
159
6
9+
159
6
9+
13
6
59+
Tm
Yb
Pr
W
164
71+
171
74
Lu
16
4
71+
Hf
14
5
6
3+
122
53+
Gd
I
175
7
6+
161
70
+
138
6
0+161
70
+
16
8
7
3+16
8
73+
Os
TaW
Yb
Nd
Lu
14
9
65+
Tb
156
68
+
156
6
8+
Er
Tm
154
67+
154
67+
HoEr
163
71+
147
64
+
14
7
6
4+
147
6
4+
Dy
Tb
Gd
Lu
165
72
+1
65
7
2+
17
2
7
5+
163
7
1+
170
74
+
Hf
TaRe
W
Hf
10000 20000 30000 40000 50000 60000 70000 80000 90000 100000
8
7
6
5
4
3
2
1
0
Frequency / H z
Inte
nsity
/ ar
b. u
nits
m ass know n m ass unknow n
300 kHz / 60 MHz Schottky TCAP
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
Orbital EC-experiments, decay schemes
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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
Cooling at ESR
David Boutin, PhD Thesis, Univ. Giessen, 2005
8 December 2008 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
EC in Hydrogen-like Ions
FRS-ESR Experiment
EC(H-like) = 0.00219(6) s-1 (decay of 140Pr58+)
bare) = 0.00158(8) s-1 (decay of 140Pr59+)
(neutral)= 0.00341(1) s-1 G.Audi et al., NPA729 (2003) 3
Expectations:
EC(He-like) = 0.00147(7) s-1 (decay of 140Pr57+)
EC(H-like)/EC(He-like) ≈ 0.5
EC (neutral atom) ≈1
EC(H-like)/EC(He-like) = 1.49(8)
Yu. A. Litvinov et al., PRL 99, 262501 (2007)
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
S. Typel and L. Grigorenko
Probability of EC Decay
µ = +2.7812 µN (calc.)
Neutral 140Pr: P = 2.381
Gamow-Teller transition
Electron Capture in Hydrogen-like Ions
H-like 140Pr: P = 3
He-like 140Pr: P = 2
Theory: Z. Patyk et al., PR C77, 014306 (2008)The H-like ion decays by 20% faster than the neutral atom!
λ(H)/λ(He) = (2I+1)/(2F+1)
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
Nuclear Decay of Stored Single Ions
Time/channel = 30 sec.
Amplitude distributions corresponding to 1,2,3-particles; 1 frame = 128 msec.
Am
plitu
de
Am
plitu
de
Daughter
Mother
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'
The final data occur within +- 400 msec. in both the computer as well as in the ‘manual’ evaluations; In all cases the ‘appearance’ time has been taken into account.
N. Winckler
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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
2 140Pr58+
1 140Pr58+
1 140Ce58+
↕ Time/ch. = 64 msec
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
Properties of measured time↔frequency traces
1. Continuous observation
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
2. Parent/daughter correlation
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
2. Experimental results for EC of H-like ions: 140Pr58+
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
Fast Fourier Transform of the data of 1.+2. run
Frequency peak at f = 0.142 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
140Pr58+ all runs: 2650 EC-decays from 7102 injections
8 December 2008 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
142Pm60+: zoom on the first 33 s after injection
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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 = - 1.6 (4) a = 0.23 (4)
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
3. Some hypotheses on the non-exponential decays
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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 ) ≈ 10 -14 eV >> Ћ / T (≈ 7 s) ≈ 10 -16 eV
No third particle involved
→ daughter nucleus and neutrino entangled by momentum- and energy conservation → EPR scenario
EC in H-like ions for nuclear g.s. → g.s. transitions
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
µ = +2.7812 µN (calc.)
Coherent excitation of the 1s hyperfine states F =1/2 & F=3/2 Beat period T = h/ΔE ≈ 10-15 s
Decay can occur only from the F=1/2 (ground) state
Periodic spin flip to "sterile" F=3/2 ? → λEC reduced
Quantum beats from the hyperfine states ?
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
"Classical" quantum beats
Chow et al., PR A11(1975) 1380
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 bycos(ΔE / Ћ (t-t0))
if Δτ<< T = h/ΔE→ no information whether E1 or E2
"which path"? addition of amplitudes
- Δτ -
8 December 2008 Christophor Kozhuharov, GSI Darmstadt EC-Decay of H-Like Ions
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
Beats due to neutrino being not a mass eigenstate?
ΔEν ≈ Δ2m/2M = 3.1 · 10-16 eV Δpν ≈ - Δ2m/ 2 <pν> = 2.0 · 10-11 eV
E, p = 0 (c.m.)
M, pi2/2M
νe (mi, pi, Ei)M + p1
2/2M + E1 = E M + p2
2/2M + E2 = E"Asymptotic" conservation of E, p
m12 – m2
2 = Δ2m = 8 · 10-5 eV2
E1 – E2 = ΔEν
8 December 2008 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 · 10 -16 eV
ΔEν = Δ2m /2 M = 3.1 · 10 -16 eV
New Experiment on 118Sb (122I)
Decay scheme of 118Sb
Experiment was scheduled: 31.07.2008-18.08.2008
Decay scheme of 122I
Decay statistics
Correlations: 10.808 injections ~1080 EC-decaysMany ions: 5718 injections ~5000 EC-decays
Analyzed :I. About 60% of the overall dataII. About 20% of the overall dataAutomatic analysis is delayed
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 ?
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?