Woodruff School of Mechanical Engineering
NRE 8011/8012 and MP 6011/6012 Seminar
Nuclear & Radiological Engineering and Medical Physics Programs
Neutron Detection Refresher Course
Dr. Nolan Hertel, P.E.
Georgia Tech, NRE
Thursday, March 7, 2013 at 11:00:00 AM
Boggs Building, Room 3-47
In recent years neutron detection has been the object of renewed interest largely due to detection needs for homeland security and various other nuclear security/safeguards applications. In many applications, He-3 gas detectors were used as thermal neutron detectors and surrounded with moderating material to detect higher energy neutrons. There is now a shortage of He-3 for neutron detection applications. As a result, research efforts have been encouraged to find a replacement detection material for He-3. This seminar will review the basic physics mechanisms by which various energy neutrons are detected. The principal reactions and cross sections for detecting slow, fast and high-energy neutrons will be reviewed. The detector types that have been traditionally used for neutron detection will also be reviewed: namely gas-filled, scintillators and semiconductor-based detectors. The detector requirements for neutron spectroscopy will be presented along with a short discussion of the deconvolution of pulse-height spectra usually required to obtain a spectrum. Sources and applications of neutron detectors will be presented and the challenges that must be addressed to provide neutron detection capabilities now of interest. (this seminar uses material developed by Dr. Hertel for the 2010 and 2011 IEEE Nuclear Science Symposium and Medical Imaging Conference Refresher Course)
Dr. Hertel, an internationally recognized expert in radiation detection, shielding, transport and dosimetry, joined the Georgia Tech faculty in 1993. He has been has graduated 41 MS students and 25 Ph.D. students in nuclear and radiological engineering. He has extensive experience in radiation transport, measurement and dosimetry. He has performed several neutron benchmark experiments during his career and has experience with a variety of neutron measurement techniques including time-of-flight measurements, unfolding of proton-recoil detector pulse-height spectra and activation foil data, tissue-equivalent ionization chamber measurements, and moderating neutron detection methods. During that time he has both computationally and experimentally tested the responses of a variety of radiation instruments.