F. Goldenbaum

New method for a continuous determination of the spin tune in storage rings and implications for precision experiments

A new method to determine the spin tune is described and tested. In an ideal planar magnetic ring, the spin tune-defined as the number of spin precessions per turn-is given by ν(s)=γG (γ is the Lorentz factor, G the gyromagnetic anomaly). At 970  MeV/c, the deuteron spins coherently precess at a frequency of ≈120  kHz in the Cooler Synchrotron COSY. The spin tune is deduced from the up-down asymmetry of deuteron-carbon scattering. In a time interval of 2.6 s, the spin tune was determined with a precision of the order 10^{-8}, and to 1×10^{-10} for a continuous 100 s accelerator cycle. This renders the presented method a new precision tool for accelerator physics; controlling the spin motion of particles to high precision is mandatory, in particular, for the measurement of electric dipole moments of charged particles in a storage ring.

Helium production for 0.8–2.5 GeV proton induced spallation reactions, damage induced in metallic window materials

Production cross-sections for neutrons and charged particles as well as excitation energy distributions in spallation reactions were measured recently by the NESSI-collaboration and have been employed to test different intra nuclear cascade models and the subsequent evaporation. The INCL/GEMINI code, which describes best the experimental data has been employed to calculate the damage cross-sections in Fe and Ta as well as the He/dpa ratio as a function of proton energy. For the same amount of neutron production in a typical target of a spallation neutron source the proton beam induced radiation damage in an Fe window is shown to decrease almost linearly with proton energy. For heavier materials such as Ta a similar decrease of the radiation damage is found only for energies above about 3 GeV.

Isotopic production cross sections in proton-nucleus collisions at 200 MeV

Intermediate-mass fragments from the interaction of

A combination of two 4π detectors for neutrons and charged particles.: Part I. The Berlin neutron ball—a neutron multiplicity meter and a reaction detector

^{27}\mathrm{Al}

Search for η-mesic He4 in the dd→He3nπ0 and dd→He3pπ− reactions with the WASA-at-COSY facility

,

Measurements of branching ratios for

^{59}\mathrm{Co}

\eta

, and

decays into charged particles

^{197}\mathrm{Au}

Measurement of the (n)over-right-arrowp -g d pi(0) pi(0) reaction with polarized beam in the region of the d(*)(2380) resonance

with 200-MeV protons were measured in an angular range from

Vaporization and multifragmentation in the reaction 1.2 GeV + Cu and Ag

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