Dr. M. Eric Christy Dr. M. Eric Christy Associate Professor Location:W. Frank Fountain Building108 Phone:757-727-5336 Expertise:Experimental nuclear and particle physics

Educational Background:
B.S. 1991, Northern Kentucky University; M.S. 1993, University of Kentucky; Ph.D. 1999, University of Kentucky

Research Interests:

Experimental Nuclear Physics, Quantum Chromo Dynamics, Nucleon Structure

My primary research focus is on understanding the structure of the ordinary building blocks of matter, the protons and neutrons (nucleons), in the nucleus of atoms. This is accomplished through an experimental program to determine the nucleon and nuclear structure functions, form factors, and moments via lepton scattering, and utilizing both the high intensity electron beam at Thomas Jefferson National Accelerator Facility (JLab) and the NUMI neutrino beam at Fermi National Accelerator Laboratory (Fermilab). By determining the particles produced in the collision and their momentum and trajectories we are able to infer how the basic building blocks, such as the quarks, are distributed. This allows us to both study and test the theory of the strong interactions, Quantum ChromoDynamics (QCD), which is responsible for binding the quarks into the composite hadrons, such as the proton.

As an active collaborator on the MINERnA neutrino scattering experiment at Fermilab, I have been supervising students and technicians in the successful construction of a large fraction of the scintillator detectors, which are used for both the tracking and calorimetry (energy reconstruction) of particles produced in the collision of the neutrino beam with a target proton or neutron. In collaboration with students and postdocs I am also heavily involved in both the simulation and data analysis for MINERnA utilizing the new particle physics computing facility (PPCF).

I am a Spokesperson on several experiments at JLab, including high precision 'Rosenbluth separations' in Hall C, which separate the scattering cross section for different polarizations states of the photon exchanged in the electromagnetic interaction. We are currently embarking on construction of the drift chambers for the new Super HMS spectrometer in Hall C, which will be the main charged particle tracking detectors after the upgrade of the accelerator to double the current maximum beam energy. In Hall B I am an active member of the Barely off-shell Neutron Structure (BoNuS) experiment which utilizes the novel technique of tagging the slow recoil proton produced in an interaction of the beam electron with a 'nearly' free neutron in the deuteron. This allows for the study of neutron structure which could not previously be performed due to the lack of high density free neutron targets.

Selected Publications:

  • M.E. Christy, P.E. Bosted, "Empirical fit to precision inclusive electron-proton cross- sections in the resonance region", arXiv:0712.3731 (accepted for publication in Phys.Rev.C).
  • S.P. Malace, et al., "Applications of quark-hadron duality in F2 structure function", Phys.Rev.C 80, 035207 (2009).
  • A. Psaker, W. Melnitchouk, M.E. Christy, C. Keppel, "Quark-hadron duality and truncated moments of nucleon structure functions", Phys.Rev.C 78, 025206 (2008).
  • P.E. Bosted, M.E. Christy, "Empirical fit to inelastic electron-deuteron and electron-neutron resonance region transverse cross-sections", Phys.Rev.C M 77, 065206 (2008).
  • Ingo Schienbein, Voica A. Radescu, G.P. Zeller, M. Eric Christy, C.E. Keppel, Kevin S. McFarland, W. Melnitchouk, Fredrick I. Olness, Mary Hall Reno, Fernando Steffens, Ji-Young Yu, “A Review of Target Mass Corrections”, J.Phys.G 35, 053101 (2008).
  • H.C. Fenker et al., "BoNuS: Development and Use of a Radial TPC using Cylindrical GEMs", Nucl.Instrum.Meth.A 592, 273 (2008).
  • V. Tvaskis, M.E. Christy, et al., Longitudinal-Transverse Separations of Structure Functions at Low Q2 for Hydrogen and Deuterium, Phys. Rev. Lett.98:142301 (2007)
  • S. Tripathi, D.S. Armstrong, M.E. Christy, J.H.D. Clark, T.P. Gorringe, M.D. Hasinoff, M.A. Kovash, D.H. Wright, P.A. Zolnierczuk, "Double radiative pion capture on hydrogen and deuterium and the nucleon's pion cloud", Phys.Rev.C 75, 064603 (2007).
  • T. Horn et al., "Determination of the charged pion form factor at Q2 = 1.60 and 2.45 (GeV/c)2, Phys.Rev.Lett. ,97 192001 (2006).
  • M. K. Jones et al. for the Jefferson Lab Resonance Spin Structure Collaboration, “Proton GE/GM from beam-target asymmetry, Phys.Rev.C 74, 035201 (2006).
  • Y. Liang, M.E. Christy, R. Ent, C.E. Keppel, "Q2 evolution of generalized Baldin sum rule for the proton", Phys. Rev. C 73, 065201 (2006).
  • V. Tvaskis, J. Arrington, M.E. Christy, R. Ent, C.E. Keppel, Y. Liang and G. Vittorini, "Experimental constraints on non-linearities induced by two-photon effects in elastic and inelastic Rosenbluth separations", Phys. Rev. C 73, 025206 (2006).
  • I.A. Qattan et al., "Precision Rosenbluth measurement of the proton elastic form factors", Phys. Rev.Lett. 94, 142301 (2005).
  • M. Osipenko, S. Simula, W. Melnitchouk, P. Bosted, V. Burkert, M.E. Christy, K. Griffioen, C. Keppel, S. Kuhn, G. Ricco, "Global analysis of data on the proton structure function g1 and extraction of its moments," Phys. Rev. D 71, 054007 (2005).
  • M. Osipenko, W. Melnitchouk, S. Simula, P. Bosted, V. Burkert, M.E. Christy, K. Griffioen, C. Keppel, S.E. Kuhn, “Higher twist analysis of the proton g1 structure function," Phys. Lett. B 609, 259 (2005).
  • M. E. Christy, et al., Measurements of Electron Proton Elastic Cross Sections for 0.4 < Q2 < 5.5 (GeV/c)2, Phys. Rev. C 70, 015206 (2004).