A high-rate 10B-loaded liquid scintillation detector for parity-violation studies in neutron resonances

Abstract We have developed a large-area 10 B -loaded liquid scintillation detector for parity-violation studies in neutron resonances with high instantaneous neutron fluxes from the LANSCE short-pulse spallation source. The detector has an efficiency of 95%, 85% and 71% at neutron energies of 10, 100 and 1000 eV, respectively. The neutron mean capture time in the detector is (416±5) ns . We describe the detector and the current-mode signal processing system, that can handle neutron rates up to 500 MHz.

[1]  C. M. Frankle,et al.  Ion chamber system for neutron flux measurements , 1994 .

[2]  P. Guazzoni,et al.  On the performance of helium scintillation counters , 1969 .

[3]  M. Divadeenam,et al.  Neutron cross sections , 1981 .

[4]  N. R. Roberson,et al.  Neutron Resonance Spectroscopy of 117Sn from1 eV to 1.5 keV , 1999 .

[5]  I. B. Berlman.  Handbook of flourescence spectra of aromatic molecules , 1971 .

[6]  J. Bowman,et al.  A spin reversal system for polarized epithermal neutrons , 1996 .

[7]  Hwai-Pwu Chou,et al.  Integral test of a boron-10 loaded liquid scintillator for neutron detection , 1993 .

[8]  G. E. Thomas,et al.  BORON-LOADED LIQUID SCINTILLATION NEUTRON DETECTORS , 1957 .

[9]  J. Kirkbride,et al.  Measurement of the decay times of organic scintillators , 1967 .

[10]  C. M. Frankle,et al.  An apparatus and techniques of tests for fundamental symmetries in compound-nucleus scattering with epithermal polarized neutron beams , 1993 .

[11]  F. Hambsch,et al.  Fast decay components in the scintillation gases Ar, ArN2, Xe, and HeXe excited by heavy-ion impact , 1987 .

[12]  L. Greenwood,et al.  Improved (10)B-loaded liquid scintillator with pulse-shape discrimination. , 1979, The Review of scientific instruments.

[13]  J. Szymanski,et al.  Current-mode detector for neutron time-of-flight studies☆ , 1990 .

[14]  Roberson,et al.  Parity nonconservation for neutron resonances in 238U. , 1990, Physical review letters.

[15]  C. M. Frankle,et al.  Apparatus for parity-violation study via capture /γ-ray measurements , 1999 .

[16]  C. D. Bowman,et al.  The Los Alamos National Laboratory Spallation Neutron Sources , 1990 .

[17]  C. Gould,et al.  Time reversal invariance and parity violation in neutron reactions : Dubna, Russia 4-7 May 1993 , 1994 .