James Powell

Design and Implementation of a Facility for Discovering New Scintillator Materials

We describe the design and operation of a high-throughput facility for synthesizing thousands of inorganic crystalline samples per year and evaluating them as potential scintillation detector materials. This facility includes a robotic dispenser, arrays of automated furnaces, a dual-beam X-ray generator for diffractometry and luminescence spectroscopy, a pulsed X-ray generator for time response measurements, computer-controlled sample changers, an optical spectrometer, and a network-accessible database management system that captures all synthesis and measurement data.

A simple low-cost photodiode radiation detector for monitoring in process PET radiochemistry

We herein report a compact, low-noise, detector design based on off-the-self amplifier and two-wire 4-20 mA transmitter chips that can easily be connected to standard analogue input electronics with only a single twisted pair of wires. The radiation detectors described herein are low-cost, easy to construct, and reliable.

Study of the 11C(p, γ) reaction via the indirect d(11C,12N)n transfer reaction

The 11C(p,γ)12N reaction is expected to be an important branch point in supermassive low-metallicity stars because it could produce CNO seed nuclei before the traditional triple-α process turns on. In this work, the d(11C,12N)n transfer reaction was employed to evaluate this reaction using a radioactive ion beam of 150 MeV 11C with 6 × 105 ions s−1 on target from the BEARS project at the 88 inch cyclotron at the Lawrence Berkeley National Laboratory. Excellent agreement was obtained between the experimental cross sections (θc.m. = 10.9–71.5°) and DWBA calculations. The asymptotic normalization coefficient was deduced to be .