status of the 241am(n,f) measurement @ ear2 · ear2 large collimator Ø 6 cm detectors: micromegas...
TRANSCRIPT
Status of the 241Am(n,f) measurement @ EAR2
Z. Eleme1, N. Patronis1, A. Stamatopoulos2, A. Tsinganis3, M. Kokkoris2, V. Michalopoulou2,3, M. Diakaki2,4, R. Vlastou2, L. Tassan-Got3, N.
Colonna5, J. Heyse6, M. Barbagallo3, M. Mastromarco3, D. Macina3, E. Chiaveri3 and the n_TOF Collaboration7
1 UoI, 2 NTUA, 3 CERN, 4 CEA-Cadarache, 5 INFN-Bari, 6 JRC-Geel, 7 www.cern.ch/ntof
n_TOF Collaboration Meeting
November 27th-28th, 2018, Granada
Zinovia Eleme [email protected] University of Ioannina
Introduction
1
Motivation
● 241Am is present in high-level nuclear waste● Important for different waste transmutation and recycling scenarios● 241Am(n,f) reaction is included in the NEA High Priority Request List● Present experimental uncertainties do not meet the requirements set by sensitivity
studies of advanced nuclear systems
Experimental Details
● EAR2● Large Collimator Ø 6 cm● Detectors: Micromegas● Gas: Mixture of Ar:CH
4:isoC
4H
10 (88:10:2) @ 1 bar
● Target Samples → 6 x 241Am && Neutron flux monitor samples → 2 x 235U && 2 x 238U
n_TOF Collaboration MeetingNovember 27th-28th, 2018, Granada
Experimental Set-Up
3
Sample Characteristics
241Am 235U 238U
Areal Density (ug/cm2) 4-5 9-10 73-78
Diameter (cm) 6 6 6
No. of samples 6 2 2
Total mass (mg) 0.765 0.559 4.28
Total Activity (MBq) 99.6 0.91e-4 0.53e-4
Average Activity per sample (MBq) 16.6 0.455e-4 0.265e-4
238U235U
241Am
MGAS
n_TOF Collaboration MeetingNovember 27th-28th, 2018, Granada
Experimental Set-Up
4
Improvement over previous fission experiments with μMGAS due to the MGAS due to the new pre-amps from INFN-Bari
Single Channel PCBs No crosstalk
&&
Shielded in Al boxesReduction of noise
n_TOF Collaboration MeetingNovember 27th-28th, 2018, Granada
Neutron Beam
Experimental Set-Up
4
Improvement over previous fission experiments with μMGAS due to the MGAS due to the new pre-amps from INFN-Bari
Single Channel PCBs No crosstalk
&&
Shielded in Al boxesReduction of noise
n_TOF Collaboration MeetingNovember 27th-28th, 2018, Granada
Neutron Beam
γ- flash Τreatment and Signal Reconstructionreatment and Signal Reconstruction
5
● Average g-flash subtraction for each detector →Thanks to A. Stamatopoulos!!
n_TOF Collaboration MeetingNovember 27th-28th, 2018, Granada
Quality Check of Data with 40% of Statistics
6
γ -flash residuals
alpha activity
n_TOF Collaboration MeetingNovember 27th-28th, 2018, Granada
7n_TOF Collaboration Meeting
November 27th-28th, 2018, Granada
Counting Spectra
9n_TOF Collaboration Meeting
November 27th-28th, 2018, Granada
235U Detectors
241Am Detectors238U Detectors
Counting Spectra close to MeV region
10n_TOF Collaboration Meeting
November 27th-28th, 2018, Granada
Consistent up to
a few MeV
Next Steps ..
11n_TOF Collaboration Meeting
November 27th-28th, 2018, Granada
● Check the 100% of statistics● Finalise PSA Parameters● Amplitude Cut Correction with Simulations● Mass Correction due to Impurities of the Targets
Thank you
Backup Slides
n_TOF Collaboration MeetingNovember 27th-28th, 2018, Granada
n_TOF Collaboration MeetingNovember 27th-28th, 2018, Granada
n_TOF Collaboration MeetingNovember 27th-28th, 2018, Granada