My research is focused on the experimental program at the Thomas Jefferson National Accelerator Laboratory to explore the quark nature of matter with a recent excursion into nuclear arms policy. I have also developed inquiry-based laboratories for introductory physics and undergraduate quantum mechanics.
We now know that particles called quarks are the basis for the atoms, molecules, and atomic nuclei that form us and our world. Nevertheless, how these quarks actually combine to form that matter is still a mystery. I used the unique capabilities of the CLAS detector at Jefferson Lab to make some of the first measurements of little-known electric and magnetic properties of the deuteron. In the past, scattering experiments were confined to reactions where the debris from the collision was in the same plane (usually horizontal) as the incoming and outgoing projectile. With CLAS we can measure particles that are scattered out of that plane and are sensitive to effects that have been often ignored up to now. These measurements will open a new window into the atomic nucleus.
Since 1999 I have been actively involved in science policy. I have worked on methods to secure fissile material in Russia for the US Department of Defense and on identifying new technologies for homeland security with the American Physical Society's Task Force on Countering Terrorism.
More information is available on my personal website.
Jefferson Science Associates/SURA Sabbatical Support ($13,500) (2015-2016).
CLAS12 Software Workshop support, Southeastern Universities Research Association ($7,500) (2010)
Southeastern Universities Research Association Sabbatical Fellowship ($13,500) (2009-2010)
Jefferson Laboratory sabbatical support (2009-2010)
National Science Foundation Major Research Instrumentation grant ($162,000) (2009-2011)
Southeastern Universities Research Association Sabbatical Fellowship ($10,000) (2002-2003)
Jefferson Laboratory sabbatical support (2002-2003)
National Science Foundation Major Research Instrumentation grant ($175,000) (2001-2003)
Clarence E Denoon Professor of Science (2011)
National Science Foundation Major Research Instrumentation grant ($162,000) (2009-2012)
Jefferson Laboratory sabbatical support (2009-2010)
Southeastern Universities Research Association Sabbatical Fellowship (2009-2010)
Clarence E. Denoon Professor of Science (2008)
Who's Who Among America's Teachers (2004)
University of Richmond Distinguished Educator Award (2003)
Defense Policy Fellow, American Association for the Advancement of Science (1999-2000)
M.Duer et al. Probing high-momentum protons and neutrons in neutron-rich nuclei. Nature, 560:617-621, 2018.
G.P. Gilfoyle, Future Measurements of the Nucleon Elastic Electromagnetic Form Factors at Jefferson Lab. EPJ Web Conf., 172:02004, 2018.
K. P. Adhikari et al. Measurement of the Q2 Dependence of the Deuteron Spin Structure Function g1 and its Moments at Low Q2 with CLAS. Phys. Rev. Lett., 120(6):062501, 2018.
M. Hattawy et al. First Exclusive Measurement of Deeply Virtual Compton Scattering off 4He: Toward the 3D Tomography of Nuclei. Phys. Rev. Lett., 119(20):202004, 2017.
D. Adikaram et al. Towards a resolution of the proton form factor problem: new electron and positron scattering data. Phys. Rev. Lett., 114(6):062003, 2015.
O. Hen, M. Sargsian, L.B. Weinstein, E. Piasetzky, H. Hakobyan, et al. Momentum sharing in imbalanced Fermi systems. Science, 346:614{617, 2014.
Gyurjyan, V., Abbott, D., Carbonneau, J., Gilfoyle, G., Heddle, D., Heyes, G., Paul, S., Timmer, C., Weygand, D. & Wolin, E. CLARA: A contemporary approach to physics data processing. J.Phys.Conf.Ser. 331 (2011) 032013.
Gillfoyle, G.P. Few-body physics with CLAS. Few Body Syst. 50 (2011) 15-22.
Daniel, A. et al. CLAS Collaboration. Measurement of the nuclear multiplicity ratio for K0s hadronization at CLAS. Phys.Lett. B706 (2011) 26-31.
Wood, M. et al. (CLAS Collaboration). Absorption of the omega and phi Mesons in Nuclei. Phys. Rev. Lett. 105 (2010) 112301.
Baghdasaryan, H. et al. (CLAS Collaboration). Tensor Correlations Measured in 3He(e,e′pp)n. Phys. Rev. Lett. 105 (2010) 222501.
Lachniet, J., Afanasev, A., Arenhövel, H., Brooks, W.K., Gilfoyle, G.P., Higinbotham, D., Jeschonnek, S., Quinn, B., Vineyard, M.F., et al. (The CLAS Collaboration). Precise Measurement of the Neutron Magnetic Form Factor 
in the Few-GeV
Region. Phys. Rev. Lett. 102 (2009) 192001.
Girod, F.X., Gilfoyle, G.P., et al. Deeply Virtual Compton Scattering Beam-Spin Asymmetries. Physical Review Letters, 100 (2008) 162002.
Ireland, D.G., Gillfoyle, G.P., et al. A Bayesian analysis of pentaquark signals from CLAS data. Physical Review Letters, 100 (2008) 052001.
Park, K., Gillfoyle, G.P., et. al. (2008) Cross sections and bean asymmetries for ep→enpi+ in the Nucleon Resonance Region of 1.7 < Q² < 4.5 GeV². Physical Review C, 77 (2008) 015208.
Computational methods
Nuclear non-proliferation and science policy
Active learning strategies in introductory and advanced physics courses