The objective of this JRA is to perform significant further developments on the science and technology of cryogenically cooled beam sources with applications in various research fields.

Description of work and role of partners

Task 1. Cluster-jet beam source

  • IDetailed studies on the production of intense cluster-jet beams will be extended at the cluster-jet target installations at the University of Muenster (WWU) and GSI Darmstadt. The aim is to further increase the cluster-beam densities, to investigate the properties of the produced cluster-jet beams and to reduce the gas load into the vacuum chambers. Members from INFN Genoa and OeAW will participate and contribute to these
    planned activities.
  • Velocity measurements and mass spectroscopic investigations will be further extended to gain a more detailed understanding of the production of cluster-jet beams on a microscopic scale. Mass and velocity distributions will be studied as function of the relevant operation parameters, i.e. the temperature and pressure of the gas before entering the nozzle as well as the nozzle geometry itself. The measurements will be performed in close cooperation with the simulation studies to support the understanding of the clusterization process and, therefore, for the optimisation of cluster-jet sources. The measurements will be performed at the University of Muenster (WWU) with contributions from OeAW.
  • At the cluster beam installation source at the University of Muenster (WWU) a method for beam density manipulation on the second time scale will be developed.
  • Density structures observed directly behind the nozzle will be investigated by the implementation of a new tilting system, which allows modifying the nozzle-skimmer adjustment during beam operation. These activities
    will be performed at the University of Muenster (WWU) and supported by GSI Darmstadt.
  • The property of the Laval-type nozzle in a cluster-jet target is of utmost importance for the quality of the cluster-jet beam. Nozzles with the requested shape and minimum diameter are not commercially available.
    Based on a new method developed at GSI Darmstadt and INFN Genoa new fully engineered composite Laval nozzles will be produced and tested with respect to the cluster production efficiency at the FNAL-GSI-Genoa JET-Target at GSI Darmstadt.
  • A slow control system will be build up by the Andrzej Soltan Institute for Nuclear Studies (SINS) supported by GSI Darmstadt, OeAW, INFN Genoa and WWU.
  • Detailed calculations for various nozzle and gas parameters will be performed at ITEP and INFN Genoa to determine basic construction features of the cluster-jet source for the experiments. An attempt will be made to microscopically understand the clusterization process as well as the droplet formation.

Task 2. Cryogenic micro-jet source

  • Systematic studies of the interaction of ion beams with liquid droplet target beams will be carried out, with the goal to improve the performance of ion beam cooling at a  storage ring. These experiments will be performed at the Experimental Storage Ring (ESR) storage ring at GSI where a cryogenically cooled micro jet source has been  successfully installed and tested.
  • Parallel to the above interaction studies the relationship between nozzle geometry and liquid beam production will also be investigated, both on a test apparatus by means of laser-imaging techniques and under true storage ring conditions at the ESR. The major goal is to improve the internal target features (especially as time stability is concerned) at the highest target densities.

Task 3. Pellet beam sources

  • For the pellet tracking system optimization, studies on illumination conditions, detection points, camera operation and camera hardware are planned at Uppsala (UU) in order to reach close to 100% pellet detection efficiency.
  • An FPGA based system for multi-camera readout and data compression will be designed for the pellet tracking system. In addition, pellet track processing algorithms and an interface for data storage and merging with the event info acquired by the experiment’s DAQ for such a system will be developed at Uppsala (UU).
  • At the Forschungszentrum Juelich (FZJ) the production and operation of high-quality nozzles with smallest diameter of 10 μm down to 5 μm is planned. The activities will be performed together with the institutes in Moscow (ITEP and MPEI).
  • Systematic investigations towards pellet production at nozzle frequencies up to 150 kHz will be performed at the Forschungszentrum Juelich (FZJ) together with the institutes in Moscow (ITEP and MPEI).
  • The feasibility of a novel technique for the droplet production by a laser induced break up of a hydrogen liquid will be investigated at Uppsala (UU) together with an institute from Moscow (ITEP).





The HadronPhysics3 project is supported by the European Union
under the 7th Framework Capacities Programme in the area of Research Infrastructures (RI).