Hamburg Isochronous Cyclotron Research Articles

Methods of element analysis by the use of charged particles from the Hamburg Isochronous Cyclotron

The applicability of charged particles induced cyclic activation analysis as well as elastic scattering reactions are investigated to determine elemental concentrations in environmental material. The nuclear reactions are induced by the well focused proton-(25 MeV) and helium-3 beam (40 MeV) of the Hamburg Isochronous Cyclotron.

Angular correlation experiments in the reactions 2H(α, nα)p and 2H(α, pα)n and comparison with the Faddeev theory and the resonating group method

Abstract At the Hamburg Isochronous Cyclotron angular correlation experiments were carried out in the reactions 2 H(α, nα)p and 2 H(α, pα)n, in order to determine the tensor polarization of the ground-state resonances 5 Li ( 3 2 − ) and 5 He ( 3 2 − ) , respectively. We find that the observables for the two mirror reactions 2 H (α, n ) 5 Li and 2 H (α, p ) 5 He are charge-dependent. This result is interpreted as evidence for a violation of charge symmetry. In the whole phase-space region absolute break-up cross sections are generally well reproduced by the Faddeev theory. On the other hand, we find that the resonating group method which has up to now been mainly applied to two-body reactions can also provide valuable information for break-up reactions. The predictions of Hackenbroich, Schutte and coworkers are in quite good agreement with the measured tensor polarization of 5 He and 5 Li and the corresponding angular correlation functions.

The neutron time-of-flight facility at the Hamburg isochronous cyclotron

The neutron time-of-flight facility recently installed at the Hamburg Cyclotron Laboratory is presented. Its main constituents are eight stationary and collimated neutron scintillation detectors heavily shielded by water tanks, and a deflection system for the primary beam consisting of two bending magnets in the target area. In connection with three alternatively usable target positions, a total of 24 reaction angles between 3° and 177° almost equidistantly spaced is accessible. True 0° and 180° measurements can be performed with two optional detectors. The construction and performance of the main components including the electronic system for data handling and analysis are described. Procedures for the calibration of the neutron detectors and for the handling of background problems are discussed. Finally some representative experimental results obtained with the spectrometer are presented in connection with the nuclear physics program pursued.

Radial oscillation analysis by internal beam pulse TOF measurements at the Hamburg isochronous cyclotron

The radial motion of single internal beam pulses in a cyclotron has been studied by measuring their time-of-flight to a series of present radii. The data were analyzed in terms of the simple model of harmonic radial oscillations. Results on the oscillation frequency, the oscillation amplitude and the radial gain per turn were extracted.

Kinematically complete angular correlation experiments with position insensitive large area detectors

The reaction kinematics for angular correlation experiments with one large area detector is described. The discussion shows that under certain conditions kinematically complete experiments can be performed even if the large area detector is not position sensitive. The missing position information can be calculated from the measured kinetic energies using three-particle kinematics. The method was used at the Hamburg Isochronous Cyclotron in the investigation of the three-particle reactions α + d → α + p + n and d + d → d + p + n, and the principle was tested in the two-particle scattering process α + d → α + d. the kinematic and phase space formulae derived for correlation experiments are useful for position sensitive as well as for position insensitive detectors.

A versatile scattering set-up in use for many-particle correlation experiments at the Hamburg isochronous cyclotron Part I: Mechanical system

A very versatile system has been developed to meet most of the mechanical requirements for experimental set-ups in nuclear physics. The system components are also suitable for many other physical applications. One characteristic set-up is used to perform kinematically complete correlation experiments at the Hamburg Isochronous Cyclotron. Coplanar and non-coplanar geometry may be used to detect neutrons and charged particles in coincidence. A vacuum tank with sector shape makes the set-up equivalent to a scattering chamber of 2.4 m diameter in an angular range of 23.6°. This feature is used advantageously for scattering experiments at very small angles.

Zusammenhänge zwischen der Phasen- oder Zeitstruktur des internen Strahls und der Strahlextraktion beim Hamburger Isochronzyklotron

The influence of the phase or time structure of the internal beam on the extraction conditions has been studied for the Hamburg Isochronous Cyclotron.

Herabsetzung der Strahlimpuls-Folgefrequenz beim Hamburger Isochronzyklotron

A system for the reduction of the beam pulse repetition rate of the energy-variable Hamburg Isochronous Cyclotron comprising beam pulse supression in the cyclotron center and in the external beam is described.

Erzeugung von Zeit-Referenzsignalen für das Neutronen-Flugzeitspektrometer am Hamburger Isochronzyklotron mittels Szintillatorfolien

The generation of timing signals by scintillation foils for the fast neutron time-of-flight spectrometer at the Hamburg Isochronous Cyclotron has been studied.

Messungen der Ladungsverteilung im externen teilchenstrahl des Hamburger isochron-zyklotrons

The distribution of the charges contained in the individual beam pulse of the external beam of the Hamburg Isochronous Cyclotron has been studied.

Das strahltransportsystem am hamburger isochronzyklotron

Based on the experience with the beamhandling of the undeflected external beam of the Hamburg Isochronous Cyclotron HAIZY, a beamtransport system has been developed. The concept of this system and its realization is discussed from the physical and technical point of view.

Zeitliche strahlimpulsformung am hamburger isochronzyklotron mittels verschiedener zentraler blenden

Time shaping of the beam pulses from the Hamburg isochronous cyclotron by central diaphragms of different configuration was investigated.

Thermoelectric cooling in the scattering chamber 800 of the Hamburg isochronous cyclotron

A cooling apparatus with Peltier thermocouples for semiconductor detector for temperatures up to −72°C is described. The method of production is discussed in detail.