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The 40Ar + 208Pb multinucleon transfer reaction has been studied at Elab = 255 MeV with the large solid angle magnetic spectrometer PRISMA. Mass and charge yields, differential and total cross sections, total kinetic energy loss distributions of different channels were simultaneously measured. Angular distributions were measured in a wide angular range by matching different spectrometer angular settings. Absolute cross sections were obtained by careful evaluation of the spectrometer response function. These cross sections for different transfer channels allow the discussion of the role played by nucleon-nucleon correlations. [ABSTRACT FROM AUTHOR]

Lifetimes of high-spin states in As have been measured using Doppler shift attenuation technique with the GASP and RFD set-up. The nucleus of interest was populated in the 40Ca(32S, 3p) 69As reaction at beam energy of 95 MeV. Extracted lifetimes for the 33/2+ state at 7897 keV and 37/2+ state at 9820 keV are 72 (-45, +55) fs and 25(-25, +50) fs, respectively. The transition quadrupole moment resulting from the measurement can serve as a test of the TRS calculations. [ABSTRACT FROM AUTHOR]

The revival of transfer reaction studies benefited from the construction of the new generation large solid angle spectrometers, coupled to large γ arrays. The recent results of -particle coincident measurements in 40Ca+96Zr and 40Ar+208Pb reactions demonstrate a strong interplay between single-particle and collective degrees of freedom that is pertinent to the reaction dynamics. The development of collectivity has been followed in odd Ar isotopes populated in the 40Ar+208Pb reaction through the excitation of the 11/2- states, understood as the coupling of single particle degrees of freedom to nuclear vibration quanta. Pair transfer modes is another important degree of freedom which is presently being studied with Prisma in inverse kinematics at energies far below the Coulomb barrier. First results from the 96Zr+40Ca reaction elucidate the role played by nucleon-nucleon correlation. [ABSTRACT FROM AUTHOR]

Cluster states up to 12 MeV in the stable light nucleus 21Ne, based on the 16 O + n + α molecular configurations, have been populated in the incomplete-fusion reaction 16 8 O(7 3 Li, np)21 10 Ne at 29.4 MeV. The observation of both intra- and inter-band transitions leads to a re-interpretation of some levels in the K π = $ {\frac{{3}}{{2}}}$ - and K π = $ {\frac{{1}}{{2}}}$ - bands. The implications of this re-ordering on the octupole doublet bands are examined. The data allow a more accurate determination of some previously uncertain level energies. The “missing” I π = $ {\frac{{5}}{{2}}}$ - level is also discussed. [ABSTRACT FROM AUTHOR]

High-spin states in the neutron-rich nuclei 172,173Yb have been populated in a 170Er(7Li,(p,d,t) xn) incomplete-fusion reaction and the emitted γ-radiation was detected with the GASP array. The signature partners of the 7/2+[633] rotational band of the odd- N 173Yb isotope have been newly established and were observed up to spin values of (45/2+) and (43/2+), respectively. The ground-state band of the even-even nucleus 172Yb has been observed up to a spin value of (22+). No band crossings were found in these bands. To explain this observation, it is proposed that the static pair field is absent, considering that the neutron odd-even mass differences reach for these nuclei very small values and that the band crossing is absent in cranked shell modell calculations without pairing. The results indicate, however, that strong dynamic correlations are still present. [ABSTRACT FROM AUTHOR]

We have studied the emission of light unbound clusters,8Be and12C *(0+2), in the reactions18O +13C ?{31} Si ?{23} Ne +8Be and28Si +24Mg ?{52} Fe ?{40} Ca +12C *(0+2). The ?-ray spectra obtained in coincidence with8Be and12C *(0+2) emission have been studied relative to the statistical emission of two or three a-particles. The angular-momentum-to-energy balance of the cluster emission is compared with that of multiple-a emission. The properties of the energy spectra of the binary process and the population of the residual nuclei by cluster emission are discussed. It is observed that cluster emission carries away less excitation energy on average than the sequential emission of the individual components. [ABSTRACT FROM AUTHOR]

High-spin states of the neutron-rich vibrational nucleus 114Cd have been studied using the incomplete fusion reaction 110Pd(7Li, p2n) and the GASP spectrometer in conjunction with the ISIS Si ball. About 50 new states with excitation energies up to 7 MeV and angular momentum I < (18+) were observed and for many of them, spin and parity could be firmly assigned. The band-like stuctures in 114Cd are compared to the corresponding ones in the even-even neighbour 112Cd. [ABSTRACT FROM AUTHOR]

Lifetimes of yrast and nonyrast states of 102Pd populated via the 92Zr( 13C, 3n) reaction are measured by means of the recoil distance Doppler-shift technique with a Cologne plunger coupled to a GASP spectrometer. The event-by-event data accumulated at 24 plunger distances in the range of 0.1 μm to 9 mm are analyzed using the differential decay curve method. The resulting B(E2) values of the γ transitions depopulating yrast-band members up to the I π = 8+ state are found to deviate significantly from the corresponding predictions of the E(5) critical-point symmetry. [ABSTRACT FROM AUTHOR]

Low- and medium-spin states of the odd-odd nucleus l30La were studied by in-beam and pulsed-beam γ-ray spectroscopy using the l2lSb(l2C,3n) and II6Sn(160,pn) fusion-evaporation reactions. The decay out of theπh\11/2 ⊗ vg 11/2 and πh11/2 ⊗ vg7/2 rotational structures to the ground state has been elucidated. Spin and parity values have been assigned to most of the newly observed states, as well as to the bandheads of the rotational bands. Two isomeric states were identified and placed in the level scheme, with the characteristics Jπ = 5+, Ex = 214.0 keV, Tl/2 = 0.76(9) μs and Jμ = 6+, Ex = 319.1 keV, T 1/2 = 33(1) ns. The magnetiand quadrupole interactions of the 6+ isomeric state have been investigated by the time-differential perturbed γ-ray angular distribution method. The g factor value, g(6+) = +0.48(3), and the quadrupole coupling constant in polycrystalline metallic Sn lattice, vQ(6+)=37(4) MHz, have been derived. The experimental data are compared with the predictions of two-quasiparticles plus rotor model calculations. [ABSTRACT FROM AUTHOR]

High-spin states in 138Nd were investigated using the reaction 94Zr(48Ca, 4n), detecting coincident γ rays with the GASP spectrometer. A rich level scheme was constructed including four bands of negative parity at low spins, eight bands of dipole transitions, and eight bands of quadrupole transitions at medium spins. The cranked shell model and the tilted-axis cranking model are used to assign configurations to the observed bands, where zero pairing is assumed. For selected configurations the case of finite pairing is also considered. A consistent notation for configuration assignment that applies for both zero and finite pairing is introduced. The observed bands are interpreted as rotation around the short and long principal axes (quadrupole bands), as well as around a tilted axis (dipole bands). The dipole bands have an intermediate character, between magnetic and collective electric rotation. A pair of dipole bands is identified as candidates for chiral partners. The possible existence of the wobbling mode at low deformation and medium spins is discussed. The consistent interpretation of the multitude of observed bands strongly supports the existence of stable triaxial deformation at medium spins in 138Nd. [ABSTRACT FROM AUTHOR]

Excited states up to Jπ = 11- at 10 296 keV and Jπ = 10+ at 10 707 keV have been populated in the odd-odd 36C1 nucleus using the 24Mg(14N,2p) fusion-evaporation reaction at Elab = 31 MeV. Twenty new states and 62 new γ transitions have been identified by employing γ-γ and γ-γ-γ coincidences. Lifetimes have been investigated by the Doppler shift attenuation method. The experimental data have been compared with the results of large-scale shell-model calculations performed using different effective interactions and model spaces allowing particle-hole excitations across the N = Z = 20 shell gap. [ABSTRACT FROM AUTHOR]

We measured multinucleon transfer reactions in the 40Ar+208Pb system at an energy close to the Coulomb barrier, by employing the PRISMA magnetic spectrometer. We extracted differential and total cross sections of the different transfer channels, with a careful investigation of the total kinetic energy loss distributions. Comparisons between different systems having the same 208Pb target and with projectiles going from neutron-poor to neutron-rich nuclei, i.e., 40Ca, 58Ni, and 40Ar, as well as between the data and GRAZING calculations have been carried out. The neutron-rich (stable) 40Ar beam allowed us to get access to the channels involving proton pickup, whose behavior in connection with the production of neutron-rich heavy partner has been outlined. [ABSTRACT FROM AUTHOR]