Calvin R. Howell
Professor of Physics
Professor Howell’s research is in the area of experimental nuclear physics with emphasis on the quantum chromodynamics (QCD) description of low-energy nuclear phenomena, including structure properties of nucleons and nuclei and reaction dynamics in few-nucleon systems. The macroscopic properties of nucleon structure and the residual strong nuclear force between neutrons and protons in nuclei emerge from QCD at distances where the color interactions between quarks and gluons are strong. However, the details of the mechanisms that generate the strong nuclear force are not well understood. Effective field theories (EFT) and Lattice QCD calculations provide theoretical frames that connect low-energy nuclear phenomena to QCD. Professor Howell and collaborators are conducting experiments on few-nucleon systems that test predictions of ab-initio theory calculations for the purpose of providing insight about the QCD descriptions of low-energy nucleon interactions and structure. His current projects include measurements of the electromagnetic and spin-dependent structure properties of nucleons via Compton scattering on the proton and few-nucleon systems and studies of two- and three-nucleon interactions using few-nucleon reactions induced by photons and neutrons. In the coming years, a focus will be on investigating the neutron-neutron interaction in reactions and inside nuclei. In addition, his work includes applications of nuclear physics to national nuclear security, medical isotope production, and plant biology. Most of his research is carried out at the High Intensity Gamma-ray Source and the tandem laboratory at TUNL.
Cross-disciplinary Training in Medical Physics awarded by National Institutes of Health (Mentor). 2007 to 2013
IDBR: Development of a System for Measuring Dynamic Biological Response in Plants Using Coincidence Counting awarded by National Science Foundation (Principal Investigator). 2007 to 2012
High Voltage System for Scintillation Detectors at HIGS awarded by Department of Energy (Principal Investigator). 1997 to 2009
Operation Efficiency and Performance Enhancements and Completion of HINDA at HIGS awarded by Department of Energy (Principal Investigator). 1997 to 2009
Breast Elemental Composition Imaging awarded by National Institutes of Health (Consultant). 2004 to 2007
Measurement of Neutron-induced Reaction Cross Sections awarded by Department of Energy (Co-Principal Investigator). 2002 to 2006
Support for the 17th International IUPAP Conference on Few-Body Physics awarded by National Science Foundation (Principal Investigator). 2003 to 2004
NIST Summer Undergraduate Research Fellowship Program awarded by National Institute of Standards and Technology (Principal Investigator). 2004
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Lee, S., et al. “PhytoPET: Design and initial results of modular PET for plant biology.” Ieee Nuclear Science Symposium Conference Record, Dec. 2012, pp. 1323–25. Scopus, doi:10.1109/NSSMIC.2012.6551323. Full Text
Al-Ohali, M. A., et al. “Neutron scattering from 28Si and 32S from 8.0 to 18.9 MeV, dispersive optical model analyses, and ground-state correlations.” Physical Review C Nuclear Physics, vol. 86, no. 3, Sept. 2012. Scopus, doi:10.1103/PhysRevC.86.034603. Full Text
Fonvieille, H., et al. “Virtual Compton scattering and the generalized polarizabilities of the proton at Q2=0.92 and 1.76 GeV2.” Physical Review C Nuclear Physics, vol. 86, no. 1, July 2012. Scopus, doi:10.1103/PhysRevC.86.015210. Full Text
Weisenberger, Andrew G., et al. “PhytoBeta imager: a positron imager for plant biology.” Physics in Medicine and Biology, vol. 57, no. 13, July 2012, pp. 4195–210. Epmc, doi:10.1088/0031-9155/57/13/4195. Full Text
Kapadia, A., et al. “SU-E-T-108: 3D Measurement of Neutron Dose from a Novel Neutron Imaging Technique.” Med Phys, vol. 39, no. 6Part11, June 2012, p. 3727. Pubmed, doi:10.1118/1.4735166. Full Text
Couture, A. H., et al. “Cross-section measurements of 2H(n,np)n in symmetric star configurations.” Physical Review C Nuclear Physics, vol. 85, no. 5, May 2012. Scopus, doi:10.1103/PhysRevC.85.054004. Full Text
Arnold, C. W., et al. “Cross-section measurement of 9Be(γ,n)8Be and implications for α+α+n→9Be in the r process.” Physical Review C Nuclear Physics, vol. 85, no. 4, Apr. 2012. Scopus, doi:10.1103/PhysRevC.85.044605. Full Text
Hammond, S. L., et al. “Dipole response of 238U to polarized photons below the neutron separation energy.” Physical Review C Nuclear Physics, vol. 85, no. 4, Apr. 2012. Scopus, doi:10.1103/PhysRevC.85.044302. Full Text
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