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First Feasibility Experiment and Simulations for EXL. Hossein Moeini, for the EXL Collaboration KVI- University of Groningen. Motivation. Classical method of nuclear spectroscopy: - light ion induced direct reactions: (p,p), (p,p’), (d,p), ( ,’ )… Past and present experiments:
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First Feasibility Experiment and Simulations for EXL Hossein Moeini, for the EXL Collaboration KVI- University of Groningen
Motivation • Classical method of nuclear spectroscopy: - light ion induced direct reactions: (p,p), (p,p’), (d,p), (,’)… • Past and present experiments: - before RIB facilities – stable nuclei and mainly external targets. - now – unstable nuclei in inverse kinematics only at external targets. Unstable nuclei and internal targets • EXL at future FAIR facilities: - explore new regions of the chart of nuclides.
Feasibility setup at ESR Experimental conditions: & target density ~ 1012cm-3
Elastic Scattering Cross Section (E1>500keV) point-like * Δ 3mm FWHM 7.5 mm FWHM experiment
EXL setup at NESR • Detection systems: • Target recoils and gammas (p,,n,…) • Forward ejectiles (p,n,) • Beam-like heavy ions Gas-jet Design goals: High energy and angular resolution Low background High luminosity (<1028 cm-2s-1) Large solid angle acceptance UHV compatibility beam
ESPA Geometry by Andrei Zalite, Milano
Optimized Number of assemblies N = 12508 crystals ≈ 111 assemblies needed ηcoverage ≈ 90º & exit hole ≈ 7º - 8º 11 assemblies in η-direction η => 9 or 11 in ψ-direction ? ψ 9 assemblies in ψ-direction
EGPA Forward Ball;ψ/η-Assemblies 10 9 Gas-jet 0 8 8 7 1 7 6 2 6 3 5 5 4 4 3 beam 2 1 0
ESPA/EGPA Top View ;ψ-Assemblies 1 2 0 0 8 1 7 6 2 3 5 4 beam
Comparison of Cpu-time/event for assemblized and not-assemblized geometries
Energy Resolution for Protons for Region A 1mm ■ 0.5mm ▲ 0.1mmΔ No shell ┼
Energy Resolution for Protons for Region B 1mm ■ 0.5mm ▲ 0.1mmΔ No shell ┼
Energy Resolution for Protons for Region C 1mm ■ 0.5mm ▲ 0.1mmΔ No shell ┼
Energy Resolution for Protons for Region D 1mm ■ 0.5mm ▲ 0.1mmΔ No shell ┼
Magnetic elements done by Masoud Shafiei, University of Tehran Full Geometry
Conclusion • First experiment at ESR with ‘complete’ setup • Reaction channels could be identified • Absolute measurement of the luminosity • Agreement with simulation results • Feasibility is proven experiment with unstable beam at (N)ESR is possible • Simulations for the EXL with the full geometry available could be performed.
Participants in ESR measurement and simulations H. Emling, P. Egelhof, K. Boretzky, J.P. Meier, H. Simon, S. Ilieva, K. Mahata, T. Le Bleis, A. Chatillon, F. Aksouh, K. Beckert, P. Beller, C. Kozhuharov, Y. Litvinov, C. Le Xuan, F. Nolden, M. Steck, T. Stöhlker, G. Ickert, U. Popp, H. Weick – GSI, Darmstadt O. Kiselev – Uni. Mainz D. Rohe, J. Jourdan, D. Werthmüller – Uni Basel A. Zalite – PNPI, St. Petersburg N. Kalantar Nayestanaki, H. Moeini – KVI, Groningen M. Shafiei – Uni. Tehran S. Pascalis – Uni. Liverpool J. A. Scarpaci – IPN, Orsay
Some Information Concerning EGPA EGPA forward ball (assemblized) : Ball inner radius = 67 cm Width of crystal window = 1 cm Length of crystal window = 2 cm Height of crystals = 20 cm θtol = 0.01º # of crystal rows = 51 Θ-coverage of crystal rows = 88.º Total # of crystals = 12504 # of crystals missing due to forward hole = 60 θ-range of forward hole = 10º φ-range of forward hole = 10º Φ-coverage of the forward assemblies = 240º # of assemblies in φ-direction = 9 # of assemblies in θ-extension = 11 EGPA backward ball (assemblized): Ball inner radius = 37 cm Width of crystal window = 1 cm Length of crystal window = 2 cm Height of crystals = 20 cm θtol = 0.01º # of crystal rows = 27 Θ-coverage of crystal rows = 84.º Total # of crystals = 1758 # of crystals missing due to backward hole = 18 θ-range of backward hole = 10º φ-range of backward hole = 10º Φ-coverage of the backward assemblies = 116º # of assemblies in φ-direction = 3 # of assemblies in θ-extension = 11