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Spallation residues produced in 1 GeV per nucleon ${}^{208}\mathrm{Pb}$ on proton reactions have been studied using the Fragment Separator facility at GSI. Isotopic production cross sections of elements from ${}_{61}\mathrm{Pm}$ to ${}_{82}\mathrm{Pb}$ have been measured down to 0.1 mb with a high accuracy. The recoil kinetic energies of the produced fragments were also determined. The obtained cross sections agree with most of the few existing gamma-spectroscopic data. The data are compared with different intranuclear-cascade and evaporation-fission models. Drastic deviations were found for a standard code used in technical applications.

We have observed dynamical diffraction in the $[[\left(0240\overline{2}4\right)$ and $[[\left(0460\overline{4}6\right)$ reflections of the icosahedral quasicrystal AlPdMn in the back-reflection geometry ( ${\ensuremath{\theta}}_{B}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}90\ifmmode^\circ\else\textdegree\fi{}$). The x-ray fluorescence from the Al and Pd atoms exhibits strong standing wave behavior, similar to that observed in crystalline materials. The data indicate a long-range order of each species of atoms, with the coherent positions attributable to distributions of the Al and Pd, which we compare to a centrosymmetric model. We observe deviations from the model which imply small departures from inversion symmetry along the twofold symmetry axis and from the expected coherent fractions for Al.

The atomic structure of the perfect Al-Pd-Mn icosahedral phase has been studied on single grain samples. Using anomalous x-ray diffraction close to the Pd edge, the partial structure factor ${\mathit{F}}_{\mathrm{Pd}}$ has been extracted. In the six-dimensional description of its structure, we find that the atomic surface cannot be described by an object with a sharp boundary. A phason Debye-Waller term has been introduced to fully account for the data. It is interpreted as resulting from random phason disorder and nonsphericity of the atomic surfaces.

The tensor polarization {ital t}{sub 20} of the recoil deuteron in elastic {ital e}-{ital d} scattering has been measured for three values of four-momentum transfer, {ital q}=3.78, 4.22, and 4.62 fm{sup {minus}1}. The data have been used to locate the first node in the charge monopole form factor of the deuteron at {ital q}=4.39{plus minus}0.16 fm{sup {minus}1}. The results for {ital t}{sub 20} are in reasonable agreement with expectations based on the nucleon-meson description of nuclear dynamics.

The spallation of Fe-56 in collisions with hydrogen at 1A GeV has been studied in inverse kinematics with the large-aperture setup SPALADIN at GSI. Coincidences of residues with low-center-of-mass kinetic energy light particles and fragments have been measured allowing the decomposition of the total reaction cross section into the different possible deexcitation channels. Detailed information on the evolution of these deexcitation channels with excitation energy has also been obtained. The comparison of the data with predictions of several deexcitation models coupled to the INCL4 intranuclear cascade model shows that only GEMINI can reasonably account for the bulk of collected results, indicating that in a light system with no compression and little angular momentum, multifragmentation might not be necessary to explain the data.

The spallation of 56Fe in collisions with hydrogen at 1A GeV has been studied in inverse kinematics with the large-aperture setup SPALADIN at GSI. Coincidences of residues with low-center-of-mass kinetic energy light particles and fragments have been measured allowing the decomposition of the total reaction cross section into the different possible deexcitation channels. Detailed information on the evolution of these deexcitation channels with excitation energy has also been obtained. The comparison of the data with predictions of several deexcitation models coupled to the INCL4 intranuclear cascade model shows that only GEMINI can reasonably account for the bulk of collected results, indicating that in a light system with no compression and little angular momentum, multifragmentation might not be necessary to explain the data.

Spallation residues and fission fragments from 1A GeV 238U projectiles irradiating a liquid hydrogen target were investigated by using the fragment separator at GSI for magnetic selection of reaction products including ray-tracing, energy-loss and time-of-flight techniques. The longitudinal-momentum spectra of identified fragments were analyzed, and evaporation residues and fission fragments could be separated. For 1385 nuclides, production cross sections down to values of 10 microb with a mean accuracy of 15%, velocities in the uranium rest frame and kinetic energies were determined. In the reaction all elements from uranium to nitrogen were found, each with a large number of isotopes.

Spallation residues and fission fragments from 1A GeV 238U projectiles irradiating a liquid hydrogen target were investigated by using the fragment separator at GSI for magnetic selection of reaction products including ray-tracing, energy-loss and time-of-flight techniques. The longitudinal-momentum spectra of identified fragments were analyzed, and evaporation residues and fission fragments could be separated. For 1385 nuclides, production cross sections down to values of 10 microb with a mean accuracy of 15%, velocities in the uranium rest frame and kinetic energies were determined. In the reaction all elements from uranium to nitrogen were found, each with a large number of isotopes.

Spallation residues produced in 1 GeV per nucleon 208Pb on proton reactions have been studied using the Fragment Separator facility at GSI. Isotopic production cross sections of elements from 61Pm to 82Pb have been measured down to 0.1 mb with a high accuracy. The recoil kinetic energies of the produced fragments were also determined. The obtained cross sections agree with most of the few existing gamma-spectroscopic data. The data are compared with different intranuclear-cascade and evaporation-fission models. Drastic deviations were found for a standard code used in technical applications.

The diffuse scattering located close to Bragg reflections has been measured on a single grain of the AlPdMn icosahedral phase using elastic neutron scattering. This diffuse scattering is mainly due to phason disorder. The intensity distribution and anisotropic shape can be reproduced in the framework of the elastic theory of quasicrystals using only the two phason elastic constants whose ratio is found to be equal to $\ensuremath{-}0.5$.

Seven differential cross sections of the reaction $p+d\ensuremath{\rightarrow}^{3}\mathrm{He}+\ensuremath{\gamma}$ have been measured at ${T}_{p}=450 \mathrm{and} 550$ MeV between 52\ifmmode^\circ\else\textdegree\fi{} and 92\ifmmode^\circ\else\textdegree\fi{} (${\ensuremath{\theta}}_{\ensuremath{\gamma}}$ c.m.). $^{3}\mathrm{He}$'s were analyzed by the SPES I spectrometer in coincidence with photons detected by Cherenkov counters. The results are about twice the cross sections of the inverse reaction measured recently by Hegerath et al. and by Argan et al. The data are consistent, however, with the $\ensuremath{\gamma}+^{3}\mathrm{He}\ensuremath{\rightleftarrows}p+d$ data of Heusch et al.

Cross sections and T/sub 20/ analyzing powers for dA..-->..pX are presented. A shoulder in the cross section previously reported at higher energies and for carbon is observed for H, C, and Ti at the same d-c.m.-frame proton momentum q = 0.35 GeV/c. At q

First results for the (d,p) reaction on /sup 6/Li, /sup 9/Be, and /sup 16/O are presented for a scattering energy T/sub d/=698 MeV at momentum transfers 2< or =q< or =5 fm/sup -1/. Simple distorted-wave Born-approximation and rescattering calculations stress the need for a more comprehensive analysis by explicitly including both the stripping amplitude and mesonic degrees of freedom.

The missing-mass spectra for the transfer reactions p( /sup 3/He, d)X and /sup 3/He(p,d)X (B = 2, T = 1) have been measured at, respectively, T3He = 2.7 GeV and T/sub p/ = 0.925 GeV. The data show a narrow structure lying on top of an important continuum, with a mass M = 2.240 +- 0.005 GeV and a width GAMMA/sub 1/2/ = 0.016 +- 0.003 GeV.

For the charge-symmetry--breaking reaction d+d..-->.. /sup 4/He+..pi../sup 0/ at T/sub d/ = 0.8 GeV around 100/sup 0/ c.m., an upper limit on the production cross section of approx. =0.8 pb/sr is obtained. This represents about a factor of 20 improvement on previous measurements, but is still a factor of 5 above expected violations.

The tensor analyzing power ${T}_{20}$ for $d\ensuremath{-}p$ elastic scattering at or near ${\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}=180\ifmmode^\circ\else\textdegree\fi{}$ has been measured at sixteen deuteron beam energies between 0.3 and 2.3 GeV. In marked disagreement with earlier work, large negative values ($|{T}_{20}|g0.6$) are found at all energies in this range, with a dip to ${T}_{20}=\ensuremath{-}1.25$ at ${T}_{d}=0.5$ GeV. The present results are compared with various model calculations.

From the interactions of a deuteron beam in a liquid-hydrogen target at energies near the $d+p\ensuremath{\rightarrow}^{3}\mathrm{He}+\ensuremath{\eta}$ threshold, $\ensuremath{\eta}$ events were selected on the basis of the momentum-analyzed $^{3}\mathrm{He}$ with a background of less than 2%. This opens the way to a $^{3}\mathrm{He}$-tagged $\ensuremath{\eta}$ beam at Saturne, with a possible flux of ${10}^{4}$-${10}^{5}$ $\ensuremath{\eta}'\mathrm{s}$ per pulse. The present data allow an evaluation of the cross section down to less than 0.5 MeV above threshold. The deuteron tensor analyzing power ${t}_{20}$ has also been measured: The small negative value found at threshold (-0.15 \ifmmode\pm\else\textpm\fi{} 0.05) seems incompatible with models based on one-pion exchange.

Negative-pion production leading to discrete excitation levels of the residual nucleus has been investigated on /sup 9/Be and /sup 12/C targets with 613-MeV protons. On the first seen spectra of /sup 13/O a strong excited peak is observed at 2.82 minus-or-plus 0.24 MeV in excitation energy. The resulting cross sections are found to be far below previously published theoretical predictions.