1. Nuclear Physics in Storage Rings
Mass Measurements and Decay Studies in the ESR
Reaction studies in the ESR
Yuri A. Litvinov
11 October 2007
Introduction
High-resolution mass spectrometry
Half-life measurements
Summary and Outlook

2. Masses: Fundamental Properties of Atomic Nuclei
Binding energies
Mass models
Shell structure
Mass
matters !
Correlations
pairing
Reaction phase space
Q-values
Reaction probabilities
The reach of nuclei
Drip lines
Specific configurations
and topologies
Nuclear astrophysics
Paths of nucleosynthesis
Fundamental symmetries
Metrology
…..

3. Measured Mass Surface

4. Secondary Beams of Short-Lived Nuclei
Storage
Ring
ESR
Linear
Accelerator
UNILAC
Fragment
Separator
FRS
Production
target
Heavy-Ion
Synchrotron
SIS

5. Production & Separation of Exotic Nuclei
About 1000 nuclear residues identified
A/Z-resolution ~10-3
J. Pereira et al., PRC (2007)
Primary MeV/u
Highly-Charged Ions (0, 1, 2 … bound electrons)
In-Flight separation within ~ 150 ns
Cocktail or mono-isotopic beams
Transmission to the ESR of about 1%

6. SMS and IMS

7. Schottky Mass Spectrometry
B. Franzke, H. Geissel, G. Münzenberg

8. SMS
4 particles with different m/q
time

9. SMS Fast Fourier Transform Sin(w1) Sin(w2) Sin(w3) Sin(w4) w1 w2 w3 w4
time

10. SMS: Broad Band Frequency Spectra
Single particles, Errors are determined by systematics and not statistics

11. Mass Distributions from Single Ions
B. Sun et al., EPJ A (2007)

12. SMS: Accuracy Dm/m ≈ 4 · 10-8 Smaller dynamic range
H. Geissel et al., Eur. Phys. J. A (in press)

13. Identification of New Isotopes
F. Bosch, et al., Int. J. Mass Spectr. 251 (2006)

14. Isochronous Mass Spectrometry
H. Wollnik, Y. Fujita, H. Geissel, G. Münzenberg, et al.

15. IMS: Time-of-Flight Spectra
Nuclei with half-lives as short as 20 ms
m/q range:
About 13% in mass-over-charge range
M. Hausmann et al., Hyperfine Interactions 132 (2001) 291
M. Matos et al., Proc. EXON 2004

16. IMS: Br Tagging
Good isochronous conditions are fulfilled only in a small range
Solution: measurement of Br or v in addition
H. Geissel et al., Eur. Phys. J. A (in press)

17. Measured Mass Surface IMS ~5 ∙10-7 Masses of more than 1100
Nuclides were measured
Mass accuracy:
SMS 1.5 ∙10-7 up to 4 ∙10-8
IMS ~5 ∙10-7
Results: ~ 350 new masses
In addition more than
300 improved mass values

18. Science is either PHYSICS or collecting STAMPS

19. Limits of Nuclear Existence

20. Two-Proton Dripline

21. Odd-Even Staggering of Nuclear Binding Energies
W. Heisenberg, Z. Phys. 78 (1932) 156
J. Bardeen, L.N. Cooper, and J.R. Schrieffer,
Phys. Rev. 108 (1957) 1175
A. Bohr, B.R. Mottelson, and D. Pines,
Phys. Rev. 110 (1958) 936

22. Five Mass Formulae to extract OES
Hafnium isotopes
Protons:
Neutrons

23. Odd-Even Staggering of Nuclear Binding Energies
Yu.A.Litvinov, Th. Bürvenich et al., Phys. Rev. Lett. 95 (2005)

24. OES in Macroscopic-Microscopic Description
Yu.A.Litvinov, Th. Bürvenich et al., Phys. Rev. Lett. 95 (2005)

25. Predictive Powers of Mass Models
H. Geissel et al., NP A746 (2004) 150c

26. Predictive Powers of Mass Models
Calculated abundances
assuming that one Sn value
is varied by 1 MeV
H. Geissel et al., AIP Conf. Proc. Vol. 831 (2006) 108

27. Atomic Mass Evaluation
AME
FRS-ESR data
1. Q-values: b-decays (b+,b-)
frequency correlations between all
measured ESR data
2. Q-values: a-decays
3. Q-values: reactions (p,n), (n,g), etc.
Combined Evaluation
~2·105 input data
4. direct measurements (traps, rings)
Yu.A. Litvinov, G. Audi et al., ILIMA Technical Proposal
6169 input data
Yu.A. Litvinov et al, NPA756 (2005) 3
A. Wapstra
G. Audi, C. Thibault, NPA729 (2003) 129

28. Half-life Measurements

29. Nuclear Decay of Stored Single Ions
Yu.A. Litvinov et al, NPA756 (2003) 3

30. Stochastic + Electron Cooling
D. Boutin, PhD Thesis, JLU Giessen, 2005

31. Half-life of Fully-Ionized 207mTl81+
207mTl (E* = 1348 keV)
T1/2(neutral) = 1.33(11) s
T1/2(bare) = 1.47(32) s
T1/2(theory) = 1.52(12) s
D. Boutin, PhD Thesis, JLU Giessen, 2005
T. Ohtsubo et al., Phys. Rev. Lett. 95 (2005)

32. Beta-Decays on the Chart of Nuclides
p-process
rp-process
np-process
Astrophysical scenarios:
high temperature = high degree of ionization
fussion

33. Fully-Ionized Atoms
John N. Bahcall, “Theory of Bound-State Beta Decay”,
Phys. Rev. 124 (1961) 495
John N. Bahcall, “Beta Decay in Stellar Interiors”,
Phys. Rev. 126 (1962) 1143
Koji Takahashi, Koichi Yokoi,
“Nuclear Beta-Decays of Highly-Ionized Heavy Atoms in Stellar Interiors”,
Nucl. Phys. A 404 (1983) 578
“Beta-Decay Rates of Highly-Ionized Heavy Atoms in Stellar Interiors”,
Atomic Data Nucl. Data Tables 36 (1987) 375

34. Half-Lives of Nuclear Isomers
laboratory frame
Neutral atom is 0.49(2) s
Fully ionized atom is 11(1) s
T1/2 (fully ionized)
T1/2 (neutral)
= 22(2)
Yu.A. Litvinov, et al., PLB 573 (2003) 80-85

35. Bound-State b-decay

36. Bound-State b-decay of 187Re
The 7 Nuclear Clocks for the Age of the Earth, the Solar System, the Galaxy, and the Universe E
T½ = 33 y
10 keV
g.s.
187Re75+ βb
Q = 62 keV
clock
T1/2[109 y]
40K/40Ar (b)
1.3
238U…Th…206Pb (a,b)
4.5
232Th…Ra…208Pb (a,b) 14
176Lu/176Hf (b) 30
187Re/187Os (b) 42
87Rb/87Sr (b) 50
147Sm/143Nd (a)
100
187Re0
10 keV
T½ = 42 Gy; Q = 2.7 keV
g.s. β-
Clayton (1964): a mother-daughter couple (187Re/187Os) is the “best” radioactive clock
F. Bosch et al., Phys. Rev. Lett. 77 (1996) 5190

37. Bound-State b-decay of 163Dy
s process: slow neutron capture and β- decay near valley of β stability at
kT = 30 keV; → high atomic charge state → bound-state β decay
p process
160
164
162
161
163
166 Dy Ho Er
r process
s process
165
T1/2 = 48 days
branchings caused by bound-state β decay
M. Jung et al., Phys. Rev. Lett. 69 (1992) 2164

38. Bound-State b-decay in 206,207Tl
λ = λb+λc+λR λb
bound/continuum branching ratio
T. Ohtsubo et al., Phys. Rev. Lett. 95 (2005)

39. Next Step: Bound-State b-decay of 205Tl
F. Bosch et al., GSI Proposal

40. Hydrogen-Like Ions
I. Iben et al., “The Effect of Be7 K-Capture on the Solar Neutrino Flux”,
Ap. J. 150 (1967) 1001
L.M. Folan, V.I. Tsifrinovich,
“Effects of the Hyperfine Interaction on Orbital Electron Capture”,
Phys. Rev. Lett. 74 (1995) 499

41. Electron Capture in Hydrogen-like Ions
Classical EC-theory:
Gamow-Teller allowed
transition 1+  0+
b+ to EC branching ratio:
lb+/lEC (neutral atom) ≈ 1
W.Bambynek et al., Rev. Mod. Phys 49, 1977
S-electron density at the nucleus:
|fS(0)|2  1/ n3
Conclusion:
H-Like ion should have 41% longer half-life
PEC (neutral atom)  2  1/ n3 = 2.4
M. Campbell et al., Nucl. Phys. A283 (1997) 413
PK (H-like)  1 * 1/ 13 = 1
lb+/lK (He-like) ≈ 1.37
lb+/lK (H-like) ≈ 2.4
lb+/lK (H-like) ≈ ? ≈ 2.74 ?

42. EC in Hydrogen-like Ions
lb+/lEC (neutral atom) ≈ 1
Expectations:
EC(H-like)/EC(He-like) ≈ 0.5
lb+/lK (H-like) ≈ 2.4
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+)
EC(H-like)/EC(He-like) = 1.49(8)
lb+/lEC(H-like) = 0.72

43. Electron Capture in Hydrogen-like Ions
Gamow-Teller transition 1+  0+
S. Typel and L. Grigorenko
µ = µN
Z. Patyk
Theory:
The H-Like ion should really decay 20% faster than neutral atom!
Probability of EC Decay
Neutral 140Pr:
P = 2.381
He-like 140Pr:
P = 2
(2I+1)/(2F+1)
H-like 140Pr:
P = 3

44. Next Step B.M. Dodsworth et al., Phys. Rev. 142 (1966) 638.
µ (64Cu) = −0.217(2) mN

45. Some speculations on the EC-decay of 7Be
A.V. Gruzinov, J.N. Bahcall, Astroph. J. 490 (1997) 437
Ionization of 7Be in the Sun can be ~ %
7Be is a key nuclide to calculate the high-energy neutrino flux from the Sun
Transition (F=1F=1) is accelerated by
(2I+1)/(2F1+1)
i.e. by 8/3
However, there are only
(2F1+1)/((2F1+1)+(2F2+1)) = 3/8
of 7Be in this state

46. Single-Particle Decay Spectroscopy

47. Sensitivity to single stored ions
Recording the correlated changes of peak intensities corresponding to mother and daughter ions
Reliable determination of the number of a few stored particles
Investigation of a selected decay branch, e.g. pure electron capture decay
Systematical effects such as late cooling or feeding via atomic or nuclear decays can be disentangled
F. Bosch et al., Int. J. Mass Spectr. 251 (2006) 212

48. Summary and Outlook
Two complementary methods: Schottky and Isochronous mass spectrometry.
Broad-band: simultaneous measurements of ~100 of nuclides
High accuracy: 5 ∙10-7 for the IMS and up to 4 ∙10-8 for SMS
Ultimate sensitivity and efficiency: single ion is sufficient
Short half-lives: down to ~10 ms
Ideal for measurements of large-areas of nuclides with
very low cross-sections and very short half-lives
Highly-charged ions
Ideal for decay studies relevant for astrophysical scenarios

49. FAIR - Facility for Antiproton and Ion Research
GSI today
Future facility
SIS 100/300
SIS 18
UNILAC
ESR
Super
FRS
HESR
RESR CR
FLAIR
100 m
NESR

50. ILIMA: Masses and Halflives

51. EXL: Feasibility Demonstration at the ESR
experimental conditions:
- 136Xe beam, E = 350 MeV/u circulating ions in ring  L  6  1027 cm-2 sec-1
experimental setup:
H2 gas jet target: 6 x 1012 cm-2
Si strip recoil detector in UHV
detector for slow neutrons
detectors for fast neutrons and protons
forward heavy-ion detector
3 different luminosity monitors
absolute differential 136Xe(p,p) cross section, energy threshold  500 keV  cm  0.2°
deduced nuclear matter radius:
Rm = 5.79 (15) fm
(expected value: Rm = 5.75 fm)
EXL Collaboration

52. ILIMA: Towards Isomeric Beams
1. Pure isomeric beams can be prepared if the half-life of the corresponding ground state is much shorter.
2. For isomers with large excitation energies a spatial separation by means of a fast micrometer scraper is possible. In the first experiment the isobars with a Q-value of MeV were successfully separated.
Pure beams of ions in the isomeric or ground state can be prepared alternatively.
Injection length 170 s
ILIMA Collaboration

53. FRS-ESR Half-Life and Mass Measurements F R S E S R H a l f L i f e a
Collaboration
G.Audi, K.Beckert, F.Bosch, D.Boutin, C.Brandau, T.Bürvenich, L.Chen, I.Cullen, C.Dimopoulou, A.Dolinskii, B.Fabian, T.Faestermann, B.Franzke, H.Geissel, E.Haettner, M.Hausmann, P.Kienle, O.Klepper, R.Knöbel, C.Kozhuharov, J.Kurcewicz, Y.Litvinov, S.Litvinov, Z.Liu, L.Maier, M.Mazzocco, F.Montes, G.Münzenberg, A.Musumarra, S.Nakajima, C.Nociforo, F.Nolden, T.Ohtsubo, A.Ozawa, Z.Patyk, W.Plass, T.Radon, H.Schatz, C.Scheidenberger, M.Shindo, J.Stadlmann, M.Steck, T.Stöhlker, B.Sun, T.Suzuki, P.Walker, H.Weick, N.Winckler, M.Winkler, H.Wollnik, T.Yamaguchi