Fission c k chamber Detectors Sample t o r f o f n l - PowerPoint PPT Presentation

Inelastic scattering ‹Nº› NEMEA-6, Krakow, October 2010 filters shielding dep U90Mo10 neutron beam E p l i e collimation c Fission c k chamber Detectors Sample t o r f o f n l Digitizer external trigger i Acqiris DC440 n signal a c Neutron time-of-flight with digital processing

Inelastic scattering ‹Nº› NEMEA-6, Krakow, October 2010 GAINS @ FP3/200m GELINA

Inelastic scattering ‹Nº› NEMEA-6, Krakow, October 2010 Exact angle integration 1 L 3 k d max ( ) W ( ) c k P (cos( )) 2 2 k d 4 4 k 0 1 2 d d 2 ( x ) dx 2 w ( x ) i i d d i 1 1 1 =110 o , 70 o  w 1 =1.304 x cos( ) i i  2 =150 o , 30 o w 2 =1.696 Method is insensitive to finite detector and sample size (Monte Carlo simulations)

Inelastic scattering ‹Nº› NEMEA-6, Krakow, October 2010 Neutron fluence monitoring: 235 U fission chamber Revisiting of the fluence measurement • Mass verified by alpha-counting • Study of efficiency • Control measurement at PTB (intercomparison) 30 8.4 MeV 15 MeV foreground 15 MeV raw corrected for Y A 20 C Y A Y counts ADC offset 10 plateau a*(ch)+b 0 0 1000 2000 3000 channel

Data, results ‹Nº› NEMEA-6, Krakow, October 2010 150000 440 keV 23 Na spectrum detector 10, 110 100000 counts 50000 0 0 500 1000 1500 2000 2500 Energy (keV)

Data, results ‹Nº› NEMEA-6, Krakow, October 2010

23 Na Sample ‹Nº› NEMEA-6, Krakow, October 2010 Metallic sodium sample prepared by André Moens at IRMM

Present situation ‹Nº› NEMEA-6, Krakow, October 2010 Flux normalization issue is settled 50 % of the data for Na-23 are analysed Data taking for Zr is ongoing (until end of year) Data taking for Mo is scheduled for January- February 2011