A collimation system for ELI-NP Gamma Beam System - design and simulation of performance

NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

卷:402

Article; Proceedings Paper

Paterno, G.¹  Cardarelli, P.¹  Marziani, M.^1,2  Bagli, E.¹  Evangelisti, F.^1,2  Andreotti, M.^1,2  Gambaccini, M.^1,2  Petrillo, V.³  Drebot, I.³  Bacci, A.³  Vaccarezza, C.⁴  Palumbo, L.⁵  Variola, A.⁴ 

[1] INFN, Sez Ferrara, Via G Saragat 1, I-44121 Ferrara, Italy

[2] Univ Ferrara, Dipartimento Fis & Sci Terra, Via G Saragat 1, I-44121 Ferrara, Italy

[3] INFN, Sez Milano, Via G Celoria 16, I-20133 Milan, Italy

[4] INFN, Lab Nazl Frascati, Via E Fermi 40, I-00044 Frascati, Italy

[5] Univ Roma La Sapienza, INFN, Sez Roma, Rome, Italy

关键词: Inverse Compton;    Monochromatic radiation;    X-ray and gamma sources;    Collimator;   

DOI  :  10.1016/j.nimb.2017.03.057

来源: Elsevier

【 摘 要 】

The purpose of this study was to evaluate the performance and refine the design of the collimation system for the gamma radiation source (GBS) currently being realised at ELI-NP facility. The gamma beam, produced by inverse Compton scattering, will provide a tunable average energy in the range between 0.2 and 20 MeV, an energy bandwidth 0.5% and a flux of about 10(8) photons/s. As a result of the inverse Compton interaction, the energy of the emitted radiation is related to the emission angle, it is maximum in the backscattering direction and decreases as the angle increase [1,2]. Therefore, the required energy bandwidth can be obtained only by developing a specific collimation system of the gamma beam, i.e. filtering out the radiation emitted at larger angles. The angular acceptance of the collimation for ELI-NP-GBS must be continuously adjustable in a range from about 700 to 60 mu rad, to obtain the required parameters in the entire energy range. The solution identified is a stack of adjustable slits, arranged with a relative rotation around the beam axis to obtain an hole with an approximately circular shape. In this contribution, the final collimation design and its performance evaluated by carrying out a series of detailed Geant4 simulations both of the high-energy and the low-energy beamline are presented. (C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

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