Download presentation
Presentation is loading. Please wait.
Published byVeronica Nicholson Modified over 9 years ago
1
Neutron inelastic cross section measurement on 28 Si Alexandru Negret Horia Hulubei National Institute for Physics and Nuclear Engineering, Bucharest, ROMANIA
2
A. Negret - Neutron inelastic cross section measurement on 28 Si Summary Introduction Experimental setup Analysis Results Conclusion
3
A. Negret - Neutron inelastic cross section measurement on 28 Si Introduction Experimental setup Analysis Results Conclusion
4
A. Negret - Neutron inelastic cross section measurement on 28 Si Neutron data
5
A. Negret - Neutron inelastic cross section measurement on 28 Si Neutron inelastic scattering
6
A. Negret - Neutron inelastic cross section measurement on 28 Si NEA High priority list – 28 Si
7
A. Negret - Neutron inelastic cross section measurement on 28 Si Experimental setup Introduction Experimental setup Analysis Results Conclusion
8
A. Negret - Neutron inelastic cross section measurement on 28 Si Overview of the experimental procedure Neutron source 200 m flight path FP3/200 cabin; GAINS + FC
9
A. Negret - Neutron inelastic cross section measurement on 28 Si GELINA neutron source Electron linac (150 MeV) + 238 U target Pulse width ~1 ns Repetition rate: 800 Hz Energy range: 0 – 25 MeV Gamma flash from bremsstrahlung Flight path: 200m (~20 neutrons/burst)
10
A. Negret - Neutron inelastic cross section measurement on 28 Si GAINS 8 HPGe detectors @ 110° & 150° (Accurate integration of angular distribution up to the sixth order of Legendre polynomials) TOF technique: Amplitude gamma energy Time neutron energy Digitizer-based acquisition (Acqiris DC440, 420 MS/s, 12 bits) Beam monitoring: 235 U Fission chamber Gamma Array for Inelasic Neutron Scattering
11
A. Negret - Neutron inelastic cross section measurement on 28 Si The digitizer-based acquisition DC440 Acqiris digitizers: 420 MS/s (2.38 ns/sample) 12 bits (4096 amplitude channels)
12
A. Negret - Neutron inelastic cross section measurement on 28 Si Experimental problems The gamma flash Time resolution Long time measurements Distance from the neutron source : FP = 200m Small neutron flux Stability of the electronics Simplification of the acquisition system The digitizer-based acquisition
13
A. Negret - Neutron inelastic cross section measurement on 28 Si Analysis Introduction Experimental setup Analysis Results Conclusion
14
A. Negret - Neutron inelastic cross section measurement on 28 Si Overview of the data analysis 8 x HPGE yieldFC yield Efficiency: Monte-Carlo simulation Multiple scattering correction: Monte-Carlo simulation Gamma Production cross sections NDS: level scheme Total inelastic cross section Level cross sections
15
A. Negret - Neutron inelastic cross section measurement on 28 Si Efficiency simulation: MCNP vs GEANT4 MCNP simulation by C. Borcea GEANT4 sumulation by D. Deleanu
16
A. Negret - Neutron inelastic cross section measurement on 28 Si From gammas to level cross sections L0 L1 L2 L3 10 21 20 32 31 30 100% 15% 20%10% 10 21 31 (10), (21), 31) total inelastic = (L0) = = (10) + (21)*0.15 + (31)*0.10 L0 (L2) = (21)*1.15 - (31)*0.20 L2
17
A. Negret - Neutron inelastic cross section measurement on 28 Si Limitations Imprecise Level Scheme (Nuclear Data Sheets) Isomers in the level scheme Energy range
18
A. Negret - Neutron inelastic cross section measurement on 28 Si Results Introduction Experimental setup Analysis Results Conclusion
19
A. Negret - Neutron inelastic cross section measurement on 28 Si What did we see? 28 Si + n 29 Si 28 Al + p 25 Mg +
20
A. Negret - Neutron inelastic cross section measurement on 28 Si Gamma production cross sections in 28 Si
21
A. Negret - Neutron inelastic cross section measurement on 28 Si Total inelastic cross section
22
A. Negret - Neutron inelastic cross section measurement on 28 Si Level production cross sections
23
A. Negret - Neutron inelastic cross section measurement on 28 Si Gamma cross sections for other channels
24
A. Negret - Neutron inelastic cross section measurement on 28 Si Conclusions Introduction Experimental setup Analysis Results Conclusions
25
A. Negret - Neutron inelastic cross section measurement on 28 Si Conclusions 1/3. We measured: 4 gamma production cross sections for 28 Si(n,n’) 28 Si total cross section for 28 Si(n,n’) 28 Si accurate up to 6.2 MeV 4 level cross sections from 28 Si(n,n’) 28 Si 1 gamma production cross sections from 28 Si(n,p) 28 Al 1 gamma production cross sections from 28 Si(n, ) 25 Mg
26
A. Negret - Neutron inelastic cross section measurement on 28 Si Conclusions 2/3. Efficiency procedure We verified the procedure used in the calculation of the efficiency of the HPGe detectors for the extended target: MCNPGEANT
27
A. Negret - Neutron inelastic cross section measurement on 28 Si Conclusions 3/3: New validation of the method
28
A. Negret - Neutron inelastic cross section measurement on 28 Si Thanks Arjan PlompenEC-JRC-IRMM Catalin BorceaIFIN-HH Dana DeleanuIFIN-HH
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.