Spin alignment and g-factor measurements with RISING Maria Kmiecik IFJ PAN NZ22 IFJ PAN Review 5-6 Feb IFJ PAN Review 5-6 Feb. 2009

M. Kmiecik, Feb.’09 IFJ PAN, Kraków: A. Maj, P. Bednarczyk, M. Ciemała, J. Grębosz, K. Mazurek, W. Męczyński, S. Myalski, J. Styczeń, M. Ziębliński, MK GSI Darmstadt: J. Gerl et al.... KU Leuven: G. Neyens et al. … UJ Kraków: R. Kulessa, UW Warszawa: M. Pfützner, University of Sofia: D.L. Balabanski et al. … g-RISING collaboration Rare Isotope Spectroscopic INvestigation at GSI

M. Kmiecik, Feb.’09 motivation  magnetic moments  =g*I – probe for investigation of single-particle configuration properties (spin, parity, proton/neutron characters)  spin aligned nuclei – necessary for the magnetic moments study spin alignment of nuclei with isomeric states produced in the fragmentation reaction has been studied so far only in:  light nuclei  intermediate energies of projectiles  K. Asahi et al., Phys. Rev. C43, 456 (1991) – 14 B (beam 18 O at 60 MeV/u)  W.-D. Schmidt-Ott et al., Z. Phys. A50, 215 (1994) – 43 Sc (beam 46 Ti at 500 MeV/u)  G. Georgiev et al., J. Phys. G28, 2993 (2002) – 68 Ni (beam 76 Ge at 61.4 MeV/u)  I. Matea et al., Phys. Rev. Lett. 93, (2004) – 61 Fe (beam 64 Ni at 54.7 MeV/u) fragmentation is the important reaction that can be used for production of exotic, e. g. neutron-rich nuclei

M. Kmiecik, Feb.’09 method - g-factor measurement TDPAD (time dependent perturbed angular distribution) method alignment Larmore frequency beam

M. Kmiecik, Feb.’09 spin alignment in fragmentation reaction in fusion reaction oblate alignment (-) Asahi model K. Asahi et al.; Phys. Rev. C43 (1991) 456 FRS selected in the experiment Is the alignment produced by reaction preserved after transport through FRS? prolate alignment (+)

M. Kmiecik, Feb.’09 spin alignment FRS Is the alignment produced by reaction preserved after transport through FRS?  The spin alignment can be lost due to pick-up of electron(s) by the fully stripped ion when it passes materials in the beam line  hyperfine interaction reduces/cancels the reaction-produced spin-orientation  Larger probability of picking-up electrons have heavy nuclei (with larger Z)  In order to minimize lost of spin alignment one can:  increase the ion velocity (~ 300 MeV/u)  reduce material on the way of transported ion

M. Kmiecik, Feb.’09 K. Vyvey et al.; Phys. Rev. C69, (2004) Ch. Stenzel et al., Nucl. Phys. A411, 248 (1983) goal of the experiment known: - lifetime: 1.57(6)  s - g-factor: (2) M. Ionescu-Bujor et al.; Physics Letters B 650 (2007) 141 Do we have alignment in heavy isotopes produced in fragmentation reaction? 192 Pb

M. Kmiecik, Feb.’09 beam g-RISING setup Al degrader SC41 slits Pb-wall

M. Kmiecik, Feb.’09 experiment Reaction: fragmentation of 238 U at 1GeV/u 9 Be g-RISING campaign at GSI B=0.16T

M. Kmiecik, Feb.’09 final focal plane A/Q X secondary fragments: o 193 Bi, 194 Bi o 190 Pb, 191 Pb, 192 Pb o 188 Tl, 189 Tl analysis

M. Kmiecik, Feb.’09 Consistent with published values:  = 1.57(6)  s g = (2) Ch. Stenzel et al., Nucl. Phys. A411, 248 (1983); K. Vyvey et al., Phys. Rev. C69, (2004); M. Jonescu-Bujor et al., Phys. Lett. B650, 141 (2007) fusion-evaporation exp state described by configuration results  = 1.54(9)  s |g| = 0.17(1)  = 1.54(9)  s |g| = 0.17(1) a 2 = 0.12(3) proven feasibility of g-factor studies in heavy nuclei produced in fragmentation of relativistic beam a 2 = 0.40 a 2 = 0.40 Yamazaki value for fully aligned spins a 2 ~ 0.30 Alignment  ≈ 30% M. Kmiecik et al. - to be published

M. Kmiecik, Feb.’09 conclusions  g-factor in heavy nucleus was measured for the first time in the fragmentation reaction of relativistic beam  preserved spin alignment was found to be large enough for the feasibility of future g-factor investigations in heavy exotic nuclei