title: Monte-Carlo simulation of noise in hard X-ray Transmission Crystal Spectrometers: identification of contributors to the background noise and shielding optimization.
abstract: Transmission crystal spectrometers (TCS) are used on many laser facilities to record hard X-ray spectra. During experiments, signal recorded on imaging plates is often degraded by a background noise. Monte-Carlo simulations made with the code GEANT4 show that this background noise is mainly generated by diffusion of MeV electrons and very hard X-rays. An experiment, carried out at LULI2000, confirmed that the use of magnets in front of the diagnostic, that bent the electron trajectories, reduces significantly this background. The new spectrometer SPECTIX (Spectromètre PETAL à Cristal en TransmIssion X), built for the LMJ/PETAL facility, will include this optimized shielding.
authors.affiliation: CEA, DAM, DIF, F-91297 Arpajon, France.
authors.forename: I
authors.initials: I
authors.lastname: Thfoin
authors.affiliation: CEA, Centre de Saclay, IRFU, F-91191 Gif-sur-Yvette, France.
authors.forename: C
authors.initials: C
authors.lastname: Reverdin
authors.affiliation: CELIA, Université de Bordeaux-CNRS-CEA, F-33405 Talence, France.
authors.forename: S
authors.initials: S
authors.lastname: Hulin
authors.affiliation: Laboratoire Kastler Brossel, ENS, CNRS, UPMC, 75005 Paris Cedex, France.
authors.forename: C I
authors.initials: CI
authors.lastname: Szabo
authors.affiliation: LULI Ecole Polytechnique, CNRS, CEA, UPMC, 91128 Palaiseau, France.
authors.forename: S
authors.initials: S
authors.lastname: Bastiani-Ceccotti
authors.affiliation: CELIA, Université de Bordeaux-CNRS-CEA, F-33405 Talence, France.
authors.forename: D
authors.initials: D
authors.lastname: Batani
authors.affiliation: LULI Ecole Polytechnique, CNRS, CEA, UPMC, 91128 Palaiseau, France.
authors.forename: E
authors.initials: E
authors.lastname: Brambrink
authors.affiliation: LULI Ecole Polytechnique, CNRS, CEA, UPMC, 91128 Palaiseau, France.
authors.forename: M
authors.initials: M
authors.lastname: Koenig
authors.affiliation: CEA, Centre de Saclay, IRFU, F-91191 Gif-sur-Yvette, France.
authors.forename: A
authors.initials: A
authors.lastname: Duval
authors.affiliation: CEA, Centre de Saclay, IRFU, F-91191 Gif-sur-Yvette, France.
authors.forename: X
authors.initials: X
authors.lastname: Leboeuf
authors.affiliation: CEA, Centre de Saclay, IRFU, F-91191 Gif-sur-Yvette, France.
authors.forename: L
authors.initials: L
authors.lastname: Lecherbourg
authors.affiliation: CEA, Centre de Saclay, IRFU, F-91191 Gif-sur-Yvette, France.
authors.forename: B
authors.initials: B
authors.lastname: Rossé
authors.affiliation: University of Milano, via Celoria 16, 20133 Milano, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Morace
authors.affiliation: CELIA, Université de Bordeaux-CNRS-CEA, F-33405 Talence, France.
authors.forename: J J
authors.initials: JJ
authors.lastname: Santos
authors.affiliation: CELIA, Université de Bordeaux-CNRS-CEA, F-33405 Talence, France.
authors.forename: X
authors.initials: X
authors.lastname: Vaisseau
authors.affiliation: CELIA, Université de Bordeaux-CNRS-CEA, F-33405 Talence, France.
authors.forename: C
authors.initials: C
authors.lastname: Fourment
authors.affiliation: CELIA, Université de Bordeaux-CNRS-CEA, F-33405 Talence, France.
authors.forename: L
authors.initials: L
authors.lastname: Giuffrida
authors.affiliation: LULI Ecole Polytechnique, CNRS, CEA, UPMC, 91128 Palaiseau, France.
authors.forename: M
authors.initials: M
authors.lastname: Nakatsutsumi