As a part of the physical-technical program of the heavy-ion therapy project at GSI we have investigated the nuclear fragmentation of high-energy ion beams delivered by the heavy-ion synchrotron SIS, using water as a tissue-equivalent target. For a direct comparison of fragmentation properties, beams of 10B, 12C, 14N, and 16O were produced simultaneously as secondary beams from a primary 18O beam and separated in flight by magnetic beam analysis. The Z-distributions of beam fragments produced in the water target were measured via energy loss in a large ionisation chamber and a scintillator telescope. From these data we obtained both total and partial charge-changing cross sections. In addition we have performed Bragg measurements using two parallel-plate ionization chambers and a water target of variable length. The detailed shape of the measured Bragg curves and the measured cross sections are in good agreement with model calculations based on semi-empirical formulae.

Light-ion beams of 20Ne, 19Ne, 18F, 16O, 15O, 14N, 12C and 10B in the energy range between 200 and 670 MeV/u were fragmented in thick targets of water, carbon, lucite, polyethylene, and aluminum. The nuclear charge composition of the fragmented beam was measured via energy loss in a large-area ionisation chamber. Using a water absorber of variable thickness up to 25 cm the elemental fragment yields were measured down to Z = 5. Their build-up and decay characteristics are described by a system of differential equations. From an analysis of the depth distributions of the surviving projectiles and the lower-Z projectile fragments, both total and partial charge-changing cross sections were obtained.

Total nuclear charge-changing cross sections σΔz in a CH2 target were measured for 54 isotopically identified secondary beams around A = 60 produced from a 1A·GeV86Kr beam via projectile fragmentation. With secondary beams between Tz = 12 and −3, the isospin dependence of σΔz was investigated systematically. Contrary to the predictions of so-called overlap formulae, the σΔz values are not a function of the projectile mass alone, but are found to depend on the projectile isospin. A comparison of the data with the predictions of the statistical abrasion model reveals that this behaviour can be understood by the combined influence of the abrasion and the ablation phase in relativistic heavy-ion collisions. On the basis of this improved understanding, previous findings of anomalously large cross sections of secondary-reaction products are discussed.

At the projectile-fragment separator FRS at GSI, longitudinal momentum distributions and production cross-sections were investigated for reactions between a 500 A×MeV86Kr beam and beryllium, copper and tantalum targets. Fragments in a wide AZ range were studied. For fragments close to the projectile the measured longitudinal momentum distributions agree qualitatively with a semi-empirical parametrization. Deviations from this simple picture are found, however, for the momentum widths of light fragments and for the momentum transfer to those fragments that differ in their AZ ratio from the most probable value. The experimental data on production cross-sections are used for testing the predictions obtained from a semi-empirical parametrization, a geometrical abrasion model and an intranuclear-cascade model. The cross-section for the formation of the doubly magic nucleus 78Ni in 86Kr fragmentation is estimated to be 17 pb.

The fragmentation of 760 A·MeV 136Xe projectiles impinging on a 27Al target has been investigated at the fragment separator FRS at GSI Darmstadt. Production cross sections for neutron rich nuclei in the 116 ≤ A ≤ 134 mass region have been determined and are compared to an empirical parametrisation as well as to model calculations. For the double magic nucleus 132Sn we extrapolate σ ≅ 0.4 ± 0.3 μbarn.

The fragmentation of a 500 MeV/u Kr-86-beam after peripheral reactions with different targets has been investigated at the projectile-fragment separator FRS at GSI. The new neutron-rich isotopes Ti-58, V-61, Cr-63, Mn-66, Fe-69 and Co-71 have been unambiguously observed. Experimental production cross-sections and longitudinal momentum distributions are determined for fragments in a wide A/Z range and are in qualitative agreement with predictions from empirical parameterizations and models.

At the Fragment Separator FRS at GSI, relativistic secondary beams with nuclear mass numbers 50 less than or equal to A less than or equal to 62 were produced by the fragmentation of a 1 A x GeV Kr-86 beam and were then used as projectiles for a secondary reaction experiment. Each secondary beam particle was identified with respect to its nuclear mass and charge by a Delta E-TOF-B rho measurement. The fragmentation of stable and neutron-deficient manganese, iron, cobalt, and nickel isotopes in a carbon-hydrogen target was investigated. The experiment gives new insight into the role of the N/Z ratio of the reaction partners in the abrasion and ablation step of peripheral nuclear collisions.

The projectile fragment separator FRS designed for research and applied studies with relativistic heavy ions was installed at GSI as a part of the new high-energy SIS/ESR accelerator facility. This high-resolution forward spectrometer has been successfully used in first atomic and nuclear physics experiments using neon, argon, krypton, xenon, and gold beams in the energy range from 500 to 2000 MeV/u. For the first time relativistic xenon and gold fragments have been isotopically separated. In this contribution we describe first experiments characterizing the performance of this spectrometer.

At the fragment separator FRS at GSI, relativistic secondary beams with nuclear mass numbers 50 ⩽ A ⩽ 62 were produced by the fragmentation of a 1 A ⊙ot GeV 86Kr beam in a 9Be production target. The nuclear charge and mass numbers of the secondary-beam particles were determined by a Δ−t.o.f−Bϱ measurement. The fragmentation of stable and neutron-deficient manganese, iron, cobalt and nickel isotopes in a composite carbon-hydrogen target, placed behind the separator, was investigated. The element distributions of the secondary-fragmentation products were found to depend strongly on the neutron-to-proton ratio of the projectile. Calculations with a statistical abrasion model allow an explanation of the observed features by means of the different influences of the neutron-to-proton ratio of the projectile on the abrasion and ablation steps of the fragmentation r reaction.

From the measured yield of delta-electrons with energies between 3 and 8 MeV, emitted in the heavy-ion reaction Pb+Pb at 12 MeV/nucleon incident energy, a very fast deceleration of the nuclei in the approach phase is inferred which is much faster than predicted by the microscopic one-body dissipation model. Since the deceleration time is smaller than or comparable to the thermal equilibration time, the dissipation process is non-Markovian and therefore memory effects have to be included. This is performed on the basis of dissipative diabatic dynamics, which describes elastoplastic properties. The new diabatic one-body dissipation model reproduces the fast deceleration and the long nuclear contact time.

A complete identification in mass and nuclear charge for relativistic projectile fragments up to uranium is possible at the fragment separator (FRS) at GSI by using the scintillation detector equipment described in this paper. It was successfully used in experiments with primary beams ranging from oxygen to uranium with energies from 300 to 1000 A MeV.A mass-resolving power of A/ΔA = 407 (FWHM) was obtained for 0.95 A GeV 238U fragments.

We have measured production cross-sections of the new neutron-rich isotopes58Ti,61V,63Cr,66Mn,69Fe,71Co and neighbouring isotopes that have been identified as projectile fragments from reactions between a 500 MeV/u86Kr beam and a beryllium target. The isotope identification was performed with the zero-degree magnetic spectrometer FRS at GSI, using in addition time-of-flight and energy-loss measurements. The experimental production cross-sections for the new nuclides and neighbouring isotopes are compared with an empirical parametrization. The resulting prospects for reaching even more neutron-rich isotopes, such as the doubly-magic nuclide78Ni, are discussed.