The neutron emission in projectile fragmentation at relativistic energies was studied with the Large-Area-Neutron-Detector LAND coupled to the ALADIN forward spectrometer at the GSI Schwerionen-Synchrotron (SIS). Stable 124Sn and radioactive 107Sn and 124La beams with an incident energy of 600 MeV/nucleon were used to explore the N/Z dependence of the identified neutron source. A cluster-recognition algorithm is applied for identifying individual particles within the hit distributions registered with LAND. The obtained momentum distributions are extrapolated over the full phase space occupied by the neutrons from the projectile-spectator source. The mean multiplicities of spectator neutrons reach values of up to about 11 and depend strongly on the isotopic composition of the projectile. An effective source temperature of T \approx 2-5 MeV, monotonically increasing with decreasing impact parameter, is deduced from the transverse momentum distributions. For the interpretation of the data, calculations with the statistical multifragmentation model were performed. The variety of excited projectile spectators assumed to decay statistically is represented by an ensemble of excited sources with parameters determined previously from the fragment production observed in the same experiments. The obtained agreement is very satisfactory for more peripheral collisions where, according to the model, neutrons are mainly emitted during the secondary decays of excited fragments. The neutron multiplicity in more central collisions is underestimated, indicating that other sources besides the modeled statistical breakup contribute to the observed neutron yield. The choice made for the symmetry-term coefficient of the liquid-drop description of produced fragments has a weak effect on the predicted neutron multiplicities.

The beta decay of the most neutron-rich iron isotopes was investigated, leading to the first determination of the Fe-72 half-life and new measurements of the half-lives of Fe69-71. The experimental results are compared with theoretical predictions and presented in the context of the weak astrophysical rapid neutron capture process.

The N/Z dependence of projectile fragmentation at relativistic energies has been studied with the ALADIN forward spectrometer at the GSI Schwerionen Synchrotron (SIS). Stable and radioactive Sn and La beams with an incident energy of 600 MeV per nucleon have been used in order to explore a wide range of isotopic compositions. For the interpretation of the data, calculations with the statistical multifragmentation model for a properly chosen ensemble of excited sources were performed. The parameters of the ensemble, representing the variety of excited spectator nuclei expected in a participant-spectator scenario, are determined empirically by searching for an optimum reproduction of the measured fragment-charge distributions and correlations. An overall very good agreement is obtained. The possible modification of the liquid-drop parameters of the fragment description in the hot freeze-out environment is studied, and a significant reduction of the symmetry-term coefficient is found necessary to reproduce the mean neutron-to-proton ratios /Z and the isoscaling parameters of Z<=10 fragments. The calculations are, furthermore, used to address open questions regarding the modification of the surface-term coefficient at freeze-out, the N/Z dependence of the nuclear caloric curve, and the isotopic evolution of the spectator system between its formation during the initial cascade stage of the reaction and its subsequent breakup.

The paper describes implementation details of the Cellular Automaton Algorithm (CAA) [I. Abt, D. Emeliyanov, 1. Gorbounov, 1. Kisel, Nucl. Instrum. Methods Phys. Res. A490, 546 (2002)] for reconstruction of the particles' tracks in Transition Radiation Detector (TRD), designed for Compressed Baryonic Experiment (CBM) which will operate at the future Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany. The application and performance of cellular automaton method for standalone track finding and first level event selection are presented.

The neutron-rich nucleus 74Ni was studied with inverse-kinematics inelastic proton scattering using a 74Ni radioactive beam incident on a liquid hydrogen targetat a center-of-mass energy of 80 MeV. From the measured de-excitation gamma-rays, the population of the first 2+ state was quantified. The angle-integrated excitation cross section was determined to be 14(4) mb. A deformation length of delta = 1.04(16) fm was extracted in comparison with distorted wave theory, which suggests that the enhancement of collectivity established for 70Ni continues up to 74Ni. A comparison with results of shell model and quasi-particle random phase approximation calculations indicates that the magic character of Z = 28 or N = 50 is weakened in 74Ni.

The gamma-ray spectroscopy of Si-25 and S-29 has been performed using single neutron knockout reactions with intermediate energy beams of the exotic isotopes Si-26 and S-30. Two gamma rays have been observed in Si-25 and three in S-29. These are the first gamma rays observed in these two isotopes. These two nuclei appear to be well deformed, and possible future intermediate-energy Coulomb excitation measurements would confirm their rotational nature.

The beta decays of very neutron-rich nuclides in the Co-Zn region were studied experimentally at the National Superconducting Cyclotron Laboratory using the NSCL beta-counting station in conjunction with the neutron detector NERO. We measured the branchings for beta-delayed neutron emission (P-n values) for Co-74 (18 +/- 15%) and Ni75-77 (10 +/- 2.8%, 14 +/- 3.6%, and 30 +/- 24%, respectively) for the first time, and remeasured the P-n values of Cu77-79, Zn-79,Zn-81, and Ga-82. For Cu77-79 and for Zn-81 we obtain significantly larger P-n values compared to previous work. While the new half-lives for the Ni isotopes from this experiment had been reported before, we present here in addition the first half-life measurements of Co-75 (30 +/- 11 ms) and Cu-80 (170(-50)(+110) ms). Our results are compared with theoretical predictions, and their impact on various types of models for the astrophysical rapid neutron-capture process (r-process) is explored. We find that with our new data, the classical r-process model is better able to reproduce the A = 78-80 abundance pattern inferred from the solar abundances. The new data also influence r-process models based on the neutrino-driven high-entropy winds in core collapse supernovae.

The one-proton knockout reaction Be-9(Ti-54, Sc-53 + gamma) X at 72 MeV/nucleon has been measured. The location of the first 3/2(-) state at 2110(3) keV was confirmed, and new gamma-ray transitions were observed at 1111(2), 1273(2), 1539(4), and 2495(5) keV. Large spectroscopic strength to excited states in 53Sc was found and attributed to the knockout of sd-shell protons.

γ-ray decays from excited states in 30 Ne and inclusive and exclusive cross sections were measured in the 9 Be( 32 Mg, 30 Ne + γ)X two-proton knockout reaction at incident beam energies of 99.7 and 86.7 MeV/nucleon. The measured cross section is suppressed compared to calculations and is indicative of a reduced overlap of initial and final state wave functions in 32 Mg and 30 Ne. We interpret this reduction as due to large 4p4h amplitudes present in the 30 Ne ground state wave function, but not 32 Mg. Such large intruder components are predicted to help stabilize the heavier fluorine isotopes against neutron emission.

Excited states in the neutron-rich 121, 123, 125Ag were studied via the fragmentation of a 136Xe beam at 120MeV/nucleon in a thick 9Be target. The levels in 121Ag were populated in the \( \beta\) decay of 121Pd while those assigned to 123, 125Ag were identified via isomer spectroscopy. The transitions identified in 121Ag are consistent with the \( \gamma\) -rays reported in 117, 119Ag . The newly observed transitions were placed in the level schemes of 123, 125Ag based on the analysis of \( \gamma\) -\( \gamma\) coincidences and the systematics. We attribute the onset of isomerism in the 123, 125Ag isotopes to the drop in energy of the negative-parity levels similar to the 5- state in the even-even Cd cores. The proposed level scheme for 125Ag is well described by the NuShellX shell model calculations.

Recently, it has been observed that events with the same total transverse energy of light charged particles (LCP) in the quasitarget region, E-perpendicular to 12(QT), show two quite distinct reaction scenarios in the projectile domain: multifragmentation and residue production. This phenomenon has been dubbed "bimodality." Using quantum molecular dynamics calculations we demonstrate that this observation is very general. It appears in collisions of all symmetric systems larger than Ca and at beam energies between 50A MeV and 600A MeV and is due to large fluctuations of the impact parameter for a given E-perpendicular to 12(QT). Investigating in detail the E-perpendicular to 12(QT) bin in which both scenarios are present, we find that neither the average fragment momenta nor the average transverse and longitudinal energies of fragments show the behavior expected from a system in statistical equilibrium, in experiment as well as in QMD simulations. On the contrary, the experimental as well as the theoretical results point toward a fast process. This observation questions the conjecture that the observed bimodality is due to the coexistence of two phases at a given temperature in finite systems.

Excited states in the neutron-rich Ag were studied via the fragmentation of a Xe beam at 120MeV/nucleon in a thick Be target. The levels in Ag were populated in the β decay of Pd while those assigned to Ag were identified via isomer spectroscopy. The transitions identified in Ag are consistent with the γ-rays reported in Ag. The newly observed transitions were placed in the level schemes of Ag based on the analysis of γ-γ coincidences and the systematics. We attribute the onset of isomerism in the Ag isotopes to the drop in energy of the negative-parity levels similar to the 5− state in the even-even Cd cores. The proposed level scheme for Ag is well described by the NuShellX shell model calculations. PACS. 23.40.-s β decay; double β decay; electron and muon capture – 23.35.+g Isomer decay – 21.60.Cs Shell model – 25.70.Mn Projectile and target fragmentation

A beta-decay study of Cu-77 has been performed at the ISOLDE mass separator with the aim to deduce its beta-decay properties and to obtain spectroscopic information on Zn-77. Neutron-rich copper isotopes were produced by means of proton- or neutron-induced fission reactions on U-238. After the production, Cu-77 was selectively laser ionized, mass separated and sent to different detection systems where beta-gamma and beta-n coincidence data were collected. We report on the deduced half-live, decay scheme, and possible spin assignment of 77Cu.

S. Ettenauer,1,* H. Zwahlen,1,2 P. Adrich,1 D. Bazin,1 C. M. Campbell,1 J. M. Cook,1,2 A. D. Davies,1,2 D.-C. Dinca,1,2 A. Gade,1,2 T. Glasmacher,1,2 J.-L. Lecouey,1 W. F. Mueller,1 T. Otsuka,3,4 R. R. Reynolds,5 L. A. Riley,6 J. R. Terry,1,2 Y. Utsuno,7 and K. Yoneda1 1National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824, USA 2Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA 3Department of Physics and Center for Nuclear Study, University of Tokyo, Hongo, Tokyo 113-0033, Japan 4RIKEN, Hirosawa, Wako-shi, Saitama 351-0198, Japan 5Department of Physics, Florida State University, Tallahassee, Florida 32306, USA 6Department of Physics and Astronomy, Ursinus College, Collegeville, Pennsylvania 19426, USA 7Japan Atomic Energy Research Institute, Tokai, Ibaraki 319-1195, Japan (Received 2 April 2008; published 15 July 2008)

Low-spin states were studied in $^{30}\mathrm{Al}$ following the \ensuremath{\beta} decay of $^{30}\mathrm{Mg}$ produced in the fragmentation of 140-MeV/AMU $^{48}\mathrm{Ca}$. Analysis of the $\ensuremath{\beta}\text{\ensuremath{-}}\ensuremath{\gamma}$ and $\ensuremath{\beta}\text{\ensuremath{-}}\ensuremath{\gamma}\text{\ensuremath{-}}\ensuremath{\gamma}$ coincidences revealed a new ${1}^{+}$ state at 2413 keV, confirmation of the level scheme, and a more accurate half-life measurement of 315(6) ms for the $^{30}\mathrm{Mg}$ ground state. Higher-spin states were investigated in the reaction of $^{14}\mathrm{C}$ on $^{18}\mathrm{O}$ at 22 MeV. Protons and deuterons were detected in a segmented E-\ensuremath{\Delta}E Si telescope in coincidence with one or two \ensuremath{\gamma} rays in the FSU Ge detector array. A comparison of the resulting level and decay scheme with predictions of the $\mathit{sd}$ shell model shows good agreement with all but six of the states in both excitation energy and \ensuremath{\gamma}-decay branching ratios. The root-mean-square deviations in energy of these states using the older USD and newer USDA and USDB interactions were 265, 176, and 173 keV, respectively. The remaining six states are well described as ${4}^{\ensuremath{-}}$ to ${7}^{\ensuremath{-}}$ states, similar in relative energy to those in $^{28}\mathrm{Al}$ but shifted down by about 1200 keV. These states also agree well with the predictions of shell-model calculations using the WBP interaction. A comparison of the lowest ${4}^{\ensuremath{-}}$ states in even A Na, Al, and P isotopes shows a systematic decrease in energy with increasing N and with decreasing Z. The energies of the ${4}^{\ensuremath{-}}$ states are almost identical in nuclei with the same $N\text{\ensuremath{-}}Z$ values.

The N/Z dependence of projectile fragmentation at relativistic energies has been studied in a recent experiment at the GSI laboratory with the ALADiN forward spectrometer coupled to the LAND neutron detector. Besides a primary beam of 124 Sn , also secondary beams of 124 La and 107 Sn delivered by the FRS fragment separator have been used in order to extend the range of isotopic compositions of the produced spectator sources. With the achieved mass resolution of ΔA/A ≈ 1.5%, lighter isotopes with atomic numbers Z ≤ 10 are individually resolved. The presently ongoing analyses of the measured isotope yields focus on isoscaling and its relation to the properties of hot fragments at freeze-out and on the derivation of chemical freeze-out temperatures which are found to be independent of the isotopic composition of the studied systems. The latter result is at variance with the predictions for limiting temperatures as obtained with finite-temperature Hartree-Fock calculations.

Low-spin states were studied in Al-30 following the beta decay of Mg-30 produced in the fragmentation of 140-MeV/AMU Ca-48. Analysis of the beta-gamma and beta-gamma-gamma coincidences revealed a new 1(+) state at 2413 keV, confirmation of the level scheme, and a more accurate half-life measurement of 315(6) ms for the 30Mg ground state. Higher-spin states were investigated in the reaction of C-14 on O-18 at 22 MeV. Protons and deuterons were detected in a segmented E-Delta E Si telescope in coincidence with one or two. rays in the FSU Ge detector array. A comparison of the resulting level and decay scheme with predictions of the sd shell model shows good agreement with all but six of the states in both excitation energy and gamma-decay branching ratios. The root-mean-square deviations in energy of these states using the older USD and newer USDA and USDB interactions were 265, 176, and 173 keV, respectively. The remaining six states are well described as 4(-) to 7(-) states, similar in relative energy to those in Al-28 but shifted down by about 1200 keV. These states also agree well with the predictions of shell-model calculations using the WBP interaction. A comparison of the lowest 4- states in even A Na, Al, and P isotopes shows a systematic decrease in energy with increasing N and with decreasing Z. The energies of the 4- states are almost identical in nuclei with the same N-Z values.

The SPALADIN experiment using the inverse-kinematics technique where the heavy-ion beam is sent onto a liquid-hydrogen target has been carried out at GSI (Darmstadt, Germany) in order to study the spallation of 56 Fe. On an event-by-event basis, spallation residues, light-charged fragments and neutrons have been detected in coincidence. The set-up is based on a large aperture magnet (ALADiN) equipped with a time-projection chamber (TPC), a hodoscope and a high-efficiency neutron detector. The combination of the inverse kinematics and of the acceptance of the set-up focuses the measurement on the low centre-of-mass energy fragments of the reaction essentially originating from the de-excitation of the prefragment formed at the end of the intranuclear cascade. Data taken at 1GeV per nucleon have been analysed. Preliminary results on coincidence observables are shown and compared to theoretical calculations. We emphasize on the identification of different types of multi-fragment final states which correspond to different decay channels and allow to probe different decay mechanisms.