6 papers
Efficient Machine Learning Approach for Optimizing the Timing Resolution of a High Purity Germanium Detector
R. W. Gladen, V. A. Chirayath, A. J. Fairchild +3
We describe here an efficient machine-learning based approach for the optimization of parameters used for extracting the arrival time of waveforms, in particular those generated by…
A multi-stop time-of-flight spectrometer for the measurement of positron annihilation-induced electrons in coincidence with the Doppler-shifted annihilation gamma photon
V. A. Chirayath, R. W. Gladen, A. D. McDonald +12
Here we describe an advanced multi functional, variable-energy positron beam system capable of measuring the energies of multiple positron-induced electrons in coincidence with the…
Positron Induced Electron Emission from Graphite
A. J. Fairchild, V. A. Chirayath, R. W. Gladen +2
In this paper, we present and analyze measurements of the positron induced electron spectra (PIES) from highly oriented pyrolytic graphite (HOPG). The spectra were obtained using a…
Coincident Measurement of the Energy Spectra of Doppler-Shifted Annihilation Gamma Quanta and Positron-Induced Secondary Electrons
R W Gladen, V A Chirayath, A J Fairchild +3
Preliminary results are presented from a new positron beam system currently under development at the University of Texas at Arlington for the coincident energy measurement of Doppl…
Application of Doppler Broadened Gamma Spectroscopy to Study the Surface of Graphene
A. H. Weiss, V. A. Chirayath, R. W. Gladen +4
We present Doppler broadened gamma spectra, obtained using the newly developed advanced positron beam at the University of Texas at Arlington, from a sample consisting of 6 to 8 la…
Positronium formation in graphene and graphite
V. A. Chirayath, A. J. Fairchild, R. W. Gladen +3
Positronium (Ps) formation on the surface of clean polycrystalline copper (Cu), highly oriented pyrolytic graphite (HOPG) and multi layer graphene (MLG) grown on a polycrystalline…