Recombination trapping

To minimize interference between the different plasma collection schemes used it was decided to use a spatially separated system. The antiproton collection, cooling, and compression is housed in the same superconducting magnet system as the recombination trap, but the positron accumulator is a stand-alone system connected to the main apparatus by a beam line incorporating differential pumping and a fast valve. Figure 1 shows a schematic lay-out of the apparatus and the following sub-sections describe the individual parts of the apparatus in more detail. 

Fig. 1. General lay-out of ATHENA experiment. Shown are the positron accumulator and the main magnet system holding the antiproton catching trap, the recombination trap, and the annihilation detector surrounding the recombination region...

Figure 1 is quite simple but, to our knowledge, no determination of the individual values of the activation parameters for the k(, and kd processes have previously been available. One of the primary purposes of the present work is to discuss an analysis that yields such values. These activation parameters, in turn, are used to illustrate the curvatures that exist in Eyring or Arrhenius treatments of the temperature dependences of the observed rate constants for free radical recombination, trapping and formation by thermolysis of a covalent precursor in solution. 

While there have been reports of time-resolved photoluminescence [65-68] and electroluminescence experiments [69-71] for the study of recombination, trapping and detrapping of photogenerated charge carriers, potential modulation has scarcely been used. An illustration of the possibilities of this approach is provided by... 

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