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Gesundheitsnetze mit ihren recht unterschiedlichen Benennungen, Zielsetzungen, Intensitaten der Marktteilnahme, Formen, Grosen und „Lebensdauern“ gibt es in Deutschland seit etwa drei Jahrzehnten. In den mittlerweile etwa 3000 bis 4000 Netzen arbeitet jeweils eine (haufig gewachsene) Auswahl von Akteuren aus Gesundheitswesen, dem Zweiten Gesundheitsmarkt, dem Sozialwesen, der Offentlichen Hand und/oder den relevanten B2B-Branchen zusammen. Uber die tatsachliche Erfolgsmessung dieser Gesundheitsnetze, manchmal auch als eher einmalige Evaluierung verbramt, dringt wenig nach ausen. Mit der skizzierten Pilotuntersuchung wird erstmals versucht, den im ubrigen Wirtschaftsleben gangigen Controlling-Ansatz hinsichtlich seiner Anwendung bei diesen mannigfaltigen kooperativen Erscheinungsformen zu untersuchen.

Dissociation of a 240 MeV/u beam of He-6, incident on carbon and lead targets, has been studied in kinematically complete experiments to investigate low-lying excitation modes in the halo nucleus He-6. It is shown that alignment effects characterize the inelastic scattering and allow an unambiguous assignment of the spin of a narrow resonance observed in the excitation energy spectrum. The differential cross sections for the He-6 inelastic scattering on carbon and lead targets were deduced from the measured moments of the two neutrons and the a-particle. An analysis of these distributions shows that quadrupole and, possibly, monopole excitations characterize the hadronic interaction, while the dipole mode is dominating in Coulomb dissociation. Neither theoretically predicted new resonance states in He-6 nor nuclear excitation of a dipole mode were found. Direct evidence has been obtained for strong suppression of Coulornb post-acceleration in direct Coulomb breakup in a lead target.

Photoabsorption cross sections of trapped V 13 + clusters were measured for energies between 1.4 eV and 6.1 eV by use of a two-photon fragmentation technique. Using two laser pulses separated by a 100-ns delay period the cross sections of hot clusters (up to 1800 K) could be compared to the values at room temperature. Whereas sodium clusters are known to exhibit pronounced temperature dependence below 300 K, no continuation of these effects to higher temperatures was found for V 13 + .

Size-selected stored metal cluster ions, ${\mathrm{V}}_{13}^{+}$, have been heated by photoexcitation ( $\ensuremath{\lambda}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}730$ to 229 nm) to well-defined excitation energies corresponding to temperatures between 1000 and 2100 K. A millisecond pump-probe photodissociation technique was applied to measure the time-resolved radiative cooling. The observed decay rates are directly related to the radiative energy loss and are explained quantitatively by the competing processes of photoemission and atom evaporation.

This work demonstrates the feasibility of in-beam γ-spectroscopy employing radioactive ion beam species at relativistic energies of E = 210 ∼ 280 A· MeV. Neutron-rich nuclei below 48Ca with neutron number between the two magic numbers 20 and 28 have been investigated. Using a Pb target, single step inelastic excitation originating mainly from Coulomb interaction takes place populating preferentially low-lying low-spin states and enabling the extraction of B(E2) values. On a C target, nucleon removal reactions are dominating and medium-spin states are populated thus offering spectroscopic information in neighboring nuclei. Cross sections of inelastic excitation are determined and compared to coupled-channels calculations. Two new states of the very neutron-rich nucleus 44Ar at 1.78(8) MeV and 2.61(16) MeV are deduced from γ-transitions.

4 pages, 3 figures.-- PACS nrs.: 27.20.+n, 24.70.+s, 25.60.Gc., Peripheral fragmentation of a 287 MeV/nucleon beam of the halo nucleus Li-11 incident on a carbon target has been studied in a fragment-neutron coincidence experiment. The momentum distribution of the Li-10 fragments gives access to the momentum distribution of the removed neutron in Li-11. From the shape of the distribution, the (1s(1/2))(2) contribution to the mixture of (1s(1/2))(2) and (0p(1/2))(2) components in the ground-state wave function was determined to he (45 ± 10)%. The angular correlation between the knocked out neutron and the one from the decay of Li-10 shows a skew distribution signaling interference of these two different parity states., This work was supported by the BMBF under Contracts No. 06 DA 820, No. 06 OF 112, and No. 06 MZ 476, and by GSI via Hochschulzusammenarbeitsvereinbarungen under Contracts No. DA RICK, No. OF ELZ, and No. MZ KRK, and partly supported by the Polish Committee of Scientific Research under Contract No. PBZ/PB03/113/09, EC under Contract No. ERBCHGE-CT92-0003, CICYT under Contract No. AEN92-0788-C02-02(M. J.G.B.), and WTZ under Contract No. RUS 609-96. One of us (B. J.) acknowledges support from an Alexander von Humboldt Research Award.

Electromagnetic and nuclear breakup of the neutron-rich Oxygen isotopes ranging from A = 17 to A = 22 is studied experimentally in reactions at energies around 600 MeV/u. The beams were produced in fragmentation reactions and separated by the GSI Fragment Separator FRS. By measuring the four-momenta of all decay products after inelastic scattering and neutron decay of the projectile, the excitation energy is determined. From the differential cross sections dσ dE ∗ for electromagnetic excitation, the E1-strength distributions can be deduced. For 18,20,22O, low-lying dipole strength is observed, exhausting about 5% of the Thomas Reiche Kuhn sumrule for energies up to 5 MeV above the continuum threshold.

T. Aumann et al. ; 11 pags.; 6 figs.; 2 tabs. ; PACS number(s): 27.20.1n, 25.60.Gc, 25.70.De, 29.30.Hs

13 pags, 5 figures.-- PACS nrs.: 24.60.−t; 25.70.Ef; 27.20.+n., Momentum distributions and invariant mass spectra from the breakup of He-6 ions with an energy of 240 MeV/u interacting with a carbon target have been studied. The data were used to extract information about the reaction mechanism which is influenced by the structure of He-6. It is found that the dominant reaction mechanism is a two-step process: knock out of one neutron followed by the decay of the He-5 resonance. The shape of the (α+n) two-body invariant mass spectrum is interpreted as mainly reflecting the 5He ground state which is a J(π) = 3/2(-) resonance. However, no evidence for correlations between cu particles and neutrons is observed in the momentum widths of the distributions. It is demonstrated that a combined analysis of the two-body invariant mass spectrum and an appropriate correlation function may be used to determine the properties of the intermediate resonance., This work was supported by the German Federal Minister for Education and Research (BMBF) under Contracts 06 DA 820, 06 OF 474 and 06 MZ 476 and by GSI via Hochschulzusammenarbeitsvereinbarungen under Contracts DARIK, OF ELK, MZ KRK and partly supported by the Polish Committee of Scientific Research under Contract PB2/P03B/113/09, EC under Contract ERBCHGE-CT92-0003 and CICYT under Contract AEN92-0788-C02-02 (MJGB) and by Deutsche Forschungsgemeinschaft (DFG) under Contract 436 RUS 130/127/1. One of us (B.J.)acknowledges the support through an Alexander von Humboldt Research Award.

A scintillating fibre detector for relativistic heavy ions with an active area of 50 × 50 cm 2 has been developed and was tested with various ion beams (1 ≤ Z ≤ 92). At count rates of up to 10 5 particles/s, the position resolution was found to be determined by the fibre width of 1 mm; depending on the nuclear charge of the beam, efficiencies between 89% and 100% and time resolutions between 800 and 200 ps (FWHM) were obtained.

The excitation of the double-phonon giant dipole resonance was observed in heavy projectile nuclei impinging on targets of high nuclear charge with energies of 500‐700 MeV/nucleon. New experimental data are presented for 136 Xe and 238 U together with further analysis of earlier data on 208 Pb. Differential cross sections ds/dE* and ds/du for electromagnetic excitations were deduced. Depending on the isotope, cross sections appear to be enhanced in comparison to those expected from a purely harmonic nuclear dipole response. The cumulative effect of excitations of two-phonon states composed of one dipole and one quadrupole phonon, of predicted anharmonicities in the double-phonon dipole response, and of damping of the dipole resonance during the collision may account for the discrepancy. In addition, decay properties of two-phonon resonances were studied and compared to that of a statistical decay.

The cross section for the 6He+n channel as a function of the relative energy shows a structure, which is interpreted as being due to the 7He I π = 3/2− ground state resonance with about equal contribution from its I π = 1/2− spin-orbit partner at 1.2(2) MeV with a width Г = 1.0(2) MeV.

Dissociation of 227 MeV/u 8He in lead and carbon targets has been studied in kinematically complete experiments, the data are compared with corresponding results for 6He.

4 pages, 1 table, 4 figures.-- Printed version published Mar 11, 2002.-- PACS nrs: 24.30.Gd; 25.60.-t; 27.20.+n, Low-lying resonance states in He-7(He-6 + n), formed after fragmentation reactions of a 227 MeV/nucleon He-8 beam on a carbon target, have been studied. Coincidences between He-6 nuclei and neutrons, corresponding to the one-neutron knockout channel in He-8, were selected. The relative energy spectrum in the He-6 + n system shows a structure, which is interpreted as the He-7 (Iπ = 3/2(-)) ground state, unbound with 0.43(2) MeV relative to the He-6 + n system and a width of Γ = 0.15(8) MeV overlapping with an excited (Iπ = 1/2(-)) state observed at 1.0(1) MeV with a width of Γ = 0.75(8) MeV., This work was supported by the BMBF under Contracts No. 06 DA 915I, No. 06 OF 838, and No. 06 MZ 864 and by GSI under Contracts No. DA RICK, No. OF ELZK, and No. MZ KRAK and partly supported by the Polish Committee of Scientific Research under Contract No. KBN/2P03B/144/10, by the EC under Contract No. ERBCHGE-CT92-0003, by CICYT under Contract No. AEN92-0788-C02-02 (M. J.G. B.), by RFBR under Contract No. 01-02-16685, and by WTZ under Contract No. RUS 674-98. One of us (B. J.) acknowledges support by Alexander von Humboldt Research.

19 pages, 3 tables, 6 figures.-- PACS nrs.: 27.20.+n; 24.70.+s; 25.06.-t.-- Available online Dec 4, 2000., Dissociation of 227 MeV/u 8He in a carbon target has been studied in kinematically complete experiments. The data include the relative energy spectrum, angular distributions in the neutron knock-out channel (6He+n) as well as diffractive dissociation and inelastic scattering into the (6He+2n) channel. The data are compared with corresponding results from the well-known halo nucleus 6He. In both cases it is found that neutron knock-out is the dominating reaction channel. The relative energy spectrum (6He+n) shows a structure, which is interpreted as being due to the Iπ=3/2− resonance in the 7He ground state with about equal contribution from its Iπ=1/2− spin–orbit partner., The 7He resonance shows a spin alignment similar to that observed in 5He, but with a smaller anisotropy indicating that the structure of the 8He ground state is more complicated than that of 6He., The data in the (6He+2n) channel were used to identify resonances in the excitation energy spectrum of 8He. If the spectrum is interpreted as two overlapping resonances, the spin-parity assignment for these is found to be 2+ and 1−, respectively., This work was supported by the BMBF under Contracts 06 DA 820, 06 OF 474 and 06 MZ 864 and by GSI via Hochschulzusammenarbeitsvereinbarungen under Contracts DA RICK, OF ELZ, MZ KRK and partly supported by the Polish Committee of Scientific Research under KBN grant No. 2 PO3B 14418, EC under contract ERBCHGE-CT92-0003, CICYT under contract AEN92-0788-C02-02 (MJGB) and WTZ under contract RUS 674-98. One of us (B.J.) acknowledges the support through an Alexander von Humboldt Research Award. The authors acknowledge fruitful discussions with Horst Lenske, Sergei Fayans and Leonid Grigorenko.

The dipole response of stable and unstable neutron-rich oxygen nuclei of masses A = 17 to A = 22 has been investigated experimentally utilizing electromagnetic excitation in heavy-ion collisions at beam energies about 600 MeV/nucleon. A kinematically complete measurement of the neutron decay channel in inelastic scattering of the secondary beam projectiles from a Pb target was performed. Differential electromagnetic excitation cross sections d sigma/dE were derived up to 30 MeV excitation energy. In contrast to stable nuclei, the deduced dipole strength distribution appears to be strongly fragmented and systematically exhibits a considerable fraction of low-lying strength.

In the present study 639 fifth through eighth grade boys and girls from a total of 14 school districts across the State of Kansas voluntarily filled out evaluative surveys for each of the following...

Angular distributions of Xe fragments produced in peripheral collisions of a 136 Xe beam ~700 MeV/nucleon! with 208 Pb and nat Sn targets were measured. Equivalent sharp-cutoff minimum impact parameters were derived on the basis of a semiclassical description for the electromagnetic excitation of one- and two-phonon giant resonances. The results are compared with current standard parametrizations of minimum impact parameters and with the soft-spheres model using realistic mass density distributions for projectile and targets. @S0556-2813~99!50611-0#