- Introduction - High-Resolution and High Accuracy Mass Spectrometry - Half-Life Measurements - Summary and Outlook Nuclear Properties far off Stability from Broad-Band Mass and Lifetime Measurements in a Storage Ring Yuri A. Litvinov International Nuclear Physics Conference June 07, 2007

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  …..

Measured Mass Surface

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

Production & Separation of Exotic Nuclei 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% Primary MeV/u About 1000 nuclear residues identified A/Z-resolution ~10 -3 J. Pereira et al., PRC (2007)

SMS and IMS

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

time SMS 4 particles with different m/q

Sin(  1 ) Sin(  2 ) Sin(  3 ) Sin(  4 ) 11 22 33 44 time Fast Fourier Transform SMS

SMS: Broad Band Frequency Spectra

SMS: Accuracy  m/m ≈ 4 · H. Geissel et al., Eur. Phys. J. A (in press)

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

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

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

Measured Mass Surface 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

Science is either PHYSICS or collecting STAMPS

Two-Proton Dripline Yu.N. Novikov et al., NP A697 (2002) 92

Yu.A. Litvinov, Th. B ü rvenich et al., PRL 95 (2005) Odd-Even Staggering of Nuclear Binding Energies

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

Predictive Powers of Mass Models H. Geissel et al., AIP Conf. Proc. Vol. 831 (2006) 108 Isotope abundances calculated by assuming that a single neutron-separation energy is varied by 1 MeV

Mass Evaluation AME 1. Q-values:  -decays (  +,  - ) 2. Q-values:  -decays 3. Q-values: reactions (p,n), (n,  ), etc. 4. direct measurements (traps, rings) FRS-ESR data frequency correlations between all measured ESR data A. Wapstra G. Audi, C. Thibault, NPA729 (2003) 129 Yu.A. Litvinov et al, NPA756 (2005) input data ~2·10 5 input data Yu.A. Litvinov, G. Audi et al., ILIMA Technical Proposal Combined Evaluation

Half-life Measurements Bound-state beta decay and cosmic clocks M. Jung et al., Physical Review Letters 69 (1992) 2164 F. Bosch et al., Physical Review Letters 77 (1996) 5190 Beta-decay of fully-ionized atoms H. Irnich et al., Physical Review Letters 75 (1995) 4182 De-excitation of isomeric states in fully-ionized atoms Yu.A. Litvinov et al., Physics Letters B573 (2003) 80 Direct observation of bound-state beta decay T. Ohtsubo et al., Physical Review Letters 95 (2005)

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

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

Less is more in EC decay FRS-ESR Experiment Expectations: EC(H-like)/EC(He-like) ≈ 0.5 EC (H-like) = 2.2(1) · s -1 EC (neutral)  = 1.9(1) · s -1 EC (He-like) = 1.5(1) · s -1 EC(H-like)/EC(He-like) = 1.5(1) EC(H-like)/EC(neutral) = 1.2(1)

Less is more in EC decay FRS-ESR Experiment EC (H-like) = 2.2(1) · s -1 EC (neutral)  = 1.9(1) · s -1 EC (He-like) = 1.5(1) · s -1 EC(H-like)/EC(He-like) = 1.5(1) EC(H-like)/EC(neutral) = 1.2(1)

Electron Capture in Hydrogen-like Ions

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  s 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

Collaboration FRS-ESR Half-Life and Mass Measurements 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 MESRFSRMeeertaaumnssssHalfLifeand