The ThomX project status

Work supported by the French Agence Nationale de la recherche as part of the program EQUIPEX under reference ANR-10-EQPX-51, the Ile de France region, CNRS-IN2P3 and Université Paris Sud XI - http://accelconf.web.cern.ch/AccelConf/IPAC2014/papers/wepro052.pdfA collaboration of seven research institutes and an industry has been set up for the ThomX project, a compact Compton Backscattering Source (CBS) based in Orsay - France. After a period of study and definition of the machine performance, a full description of all the systems has been provided. The infrastructure work has been started and the main systems are in the call for tender phase. In this paper we will illustrate the definitive machine parameters and components characteristics. We will also update the results of the different technical and experimental activities on optical resonators, RF power supplies and on the electron gun

Longitudinal impedance and coherent synchrotron radiation models for ThomX storage ring

International audienceThis article deals with the design of an impedance model (including geometric, resistive wall and coherent synchrotron radiation (CSR) wakefields) for ThomX, a 50 MeV electron storage ring designed to work in pulsed mode. The beam dynamics is very different from usual damped storage rings and is strongly dominated by collective effects. The geometric and resistive wall impedance model is obtained using simulation or analytical modelling of the individual elements and is checked using wire measurements on prototypes. The CSR is simulated in a rectangular vacuum chamber to take into account transient effects and resonances. From these models, two distinct regimes of beam dynamics stand out, driven respectively by the CSR and by the geometric impedance

Impedance Simulations and Measurements for ThomX Storage Ring

International audienceThomX is a compact Compton Backscattering Source (CBS) which is being built at LAL, Orsay, France. ThomX ring has a short circumference of 18 m and a design energy of 50 MeV. Due to the low energy of the beam and in order to avoid beam degradation it is important to evaluate the ring components impedance. A CST Particle Studio impedance simulation of the different components of the ring (BPM, bellows, optical chamber, etc.) is under way. It will be followed by a bench measurement of the longitudinal and transverse impedance using the coaxial wire method. This paper will detail the preliminary results of the ThomX storage ring impedance simulations and the measurement principle we will use