Controlled Generation and Advanced Diagnosis of Ultra-Short Plasma-Accelerated Electron Bunches

Deutsches Elektronen-Synchrotron DESY
Notkestraße 85
22607 Hamburg

       Particle accelerators are a vital tool in the investigation of the structure of matter . However, those utilising conventional radio-frequency (RF) technology are large (m-km) and expensive due to the limitation of the magnitude of the electric field (<100MV/m), which drives the acceleration. Plasma-based accelerators offer the possibility of achieving accelerating field strengths one thousand times larger. Consequently the scale of the facilities reduce to such an extent that they might be supported within an individual university or hospital.
       Plasma-based particle acceleration utilising a laser to drive the accelerating structure, the wakefield, has developed extensively since its proposal in 1979 , , including the introduction of a capillary-discharge guiding structure , and has recorded electron bunches with percent level energy spread and GeV energies. These have high current (tens of pC within a few tens of femtoseconds) also making them desirable for use in compact FELs . Additionally the transverse motion of the accelerating electrons can generate a high-brightness, coherent X-ray source .
       One of the remaining challenges is the stability and reproducibility of the acceleration and therefore of the final bunch properties. Precise control of the injection of electrons into the accelerating wakefield is necessary if this is to be improved. It has been proposed that his can be achieved by tailoring the gas target.
       We aim to build on the idea of the capillary-discharge target by developing targets with integrated gas jets. In addition modification of the capillary shaping will be used to extend the interaction length and control the transverse motion of the electrons to tune the properties of the resulting betatron oscillation. With these targets we will investigate the effect of varying parameters on bunch qualities and will determine the required condition for optimised energy gain, compression and emittance. In order to achieve this we require diagnostics capable of measuring the femtosecond-duration laser-plasma accelerated electron bunches in a single shot. We propose to utilise similar approaches to those employed in conventional accelerator diagnostics, modifying them to provide high temporal resolution and independence from multiple shot measurement.
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Dr. Charlotte Palmer
Notkestr. 85
22607 Hamburg

Phone: +49 40 8998-4960

Weiterführende Links
application/pdf Sachbericht 2013 (11KB)
application/pdf Sachbericht 2014 (50KB)
application/pdf Sachbericht 2015 (44KB)