121 research outputs found
A recoil detector for the measurement of antiproton-proton elastic scattering at angles close to 90
The design and construction of a recoil detector for the measurement of
recoil protons of antiproton-proton elastic scattering at scattering angles
close to 90 are described. The performance of the recoil detector has
been tested in the laboratory with radioactive sources and at COSY with proton
beams by measuring proton-proton elastic scattering. The results of laboratory
tests and commissioning with beam are presented. Excellent energy resolution
and proper working performance of the recoil detector validate the conceptual
design of the KOALA experiment at HESR to provide the cross section data needed
to achieve a precise luminosity determination at the PANDA experiment.Comment: 10 pages, 15 figure
Near Infrared Diode Laser THz Systems
The generation and detection of radiation in the THz frequency range can be
achieved with many different electronic and photonic concepts. Among the many
different photonic THz systems the most versatile are based on diode lasers.
In this paper we describe and review the different concepts and optimization
ideas for diode laser based THz systems in order to achieve the best
performance for different types of THz setups.</p
Machine studies for the development of storage cells at the ANKE facility of COSY
We present a measurement of the transverse intensity distributions of the
COSY proton beam at the target interaction point at ANKE at the injection
energy of 45 MeV, and after acceleration at 2.65 GeV. At 2.65 GeV, the machine
acceptance was determined as well. From the intensity distributions the beam
size is determined, and together with the measured machine acceptance, the
dimensions of a storage cell for the double-polarized experiments with the
polarized internal gas target at the ANKE spectrometer are specified. An
optimum storage cell for the ANKE experiments should have dimensions of 15mm x
20mm x 390mm (vertical x horizontal x longitudinal), whereby a luminosity of
about 2.5*10^29 cm^-2*s^-1 with beams of 10^10 particles stored in COSY could
be reached.Comment: 18 pages, 13 figures, 4 table
Measurement of the Spin-Dependence of the pbar-p Interaction at the AD-Ring
We propose to use an internal polarized hydrogen storage cell gas target in
the AD ring to determine for the first time the two total spin-dependent pbar-p
cross sections sigma_1 and sigma_2 at antiproton beam energies in the range
from 50 to 450 MeV. The data obtained are of interest by themselves for the
general theory of pbar-p interactions since they will provide a first
experimental constraint of the spin-spin dependence of the nucleon-antinucleon
potential in the energy range of interest. In addition, measurements of the
polarization buildup of stored antiprotons are required to define the optimum
parameters of a future, dedicated Antiproton Polarizer Ring (APR), intended to
feed a double-polarized asymmetric pbar-p collider with polarized antiprotons.
Such a machine has recently been proposed by the PAX collaboration for the new
Facility for Antiproton and Ion Research (FAIR) at GSI in Darmstadt, Germany.
The availability of an intense stored beam of polarized antiprotons will
provide access to a wealth of single- and double-spin observables, thereby
opening a new window on QCD spin physics.Comment: 51 pages, 23 figures, proposal submitted to the SPS committee of CER
Forward K+ production in subthreshold pA collisions at 1.0 GeV
K+ meson production in pA (A = C, Cu, Au) collisions has been studied using
the ANKE spectrometer at an internal target position of the COSY-Juelich
accelerator. The complete momentum spectrum of kaons emitted at forward angles,
theta < 12 degrees, has been measured for a beam energy of T(p)=1.0 GeV, far
below the free NN threshold of 1.58 GeV. The spectrum does not follow a thermal
distribution at low kaon momenta and the larger momenta reflect a high degree
of collectivity in the target nucleus.Comment: 4 pages, 3 figure
- …