research

My main research interest is experimental medium energy nuclear physics. Studying the structure of hadrons and understanding the transition between non-perturbative and perturbative QCD is a very important subject in nuclear and particle physics. My research at Thomas Jefferson National Accelerator Facility (JLab) in the previous years has been part of this effort. More recently I joined the MINERvA collaboration at Fermilab.
One subject in which I am involved is quark-hadron duality. My involvment in this area started with my Ph.D. topic, Inclusive Resonance Electroproduction Data from Hydrogen and Deuterium and Studies of Bloom - Gilman Duality, rewarded with the 1999 SURA PhD. Thesis Award, but now, after co-authoring several papers on this subject, I can say that this is one of my main research interests. Lately there has been a lot of renewed interest in studying both the theoretical and experimental aspects of quark-hadron duality in high energy physics. Being able to describe hadronic processes in terms of quarks and gluons or in terms of hadrons should, in principle, be possible. However, there are still basic questions that are not answered. Several experiments at Jefferson Lab will try to provide answers to some of these problems. Here is a list of some of the recent experimental papers on duality. Experiment E00-002, F₂ at Low Q², approved by the JLab PAC in 2000 with an A- rating, on which I am spokesperson, is one of these experiments. And here you can view an update for this (and three other) duality experiments that ran in Hall C in 2003. These analysis of these data is completed and several papers are in preparation. An interesting article about this experiment can be found in this article.
I am also a collaborator on several other JLab experiments that study duality and related phenomena (click here to find out more about some of these experiments). Finally, I should mention that duality was identified as one of the important scientific goals driving the proposed 12 GeV upgrade of Jefferson Lab.
Our group is also involved in the 12 GeV upgrade program at Jefferson Lab (the hodoscope detector for the new Super HMS in Hall C). For more details see the JMU-PNP website or the Hall C website.

Another interesting field in which I have been involved is electromagnetic production of strangeness. This field has become a major part of the experimental program at several nuclear and high energy physics facilities. The production of strange quarks from the nucleons and nuclei can give additional information for constraining theoretical models. In collaboration with a group of physicists from INFN Laboratory (Italy) I am currently finalizing the analysis of Sigma- photoproduction on the neutron, using data obtained at Jefferson Lab in Hall B (g10).
My research is currently supported by the National Science Foundation (NSF). You can view a copy of the grant proposal submitted to NSF in 2006 and approved in 2007.
We have many undergraduate student working in the JMU-PNP (Particle and Nuclear Physics) Group. In the past few years between 30 and 40 students participated in research projects in our labs. Below you can see some pictures that my students took during summer research .

Fermilab Research

Currently our group is part of the MINERvA collaboration at Fermilab. This collaboration is seeking to build a fully active neutrino detector to complete a physics program of high rate studies of exclusive final states in neutrino scattering, of elucidation of the connection between perturbative QCD and QCD in non-perturbative regime, and of studies of the axial current in the elastic, deep inelastic and off-forward regimes. From the vast physics program of MINERvA our group is primarily interested in the study of the transition between the perturbative and non-perturbative regimes. Neutrino-induced reactions can provide important consistency checks on the validity of duality. While deep inelastic neutrino structure functions are determined by the same set of universal parton distribution functions as in charged lepton scattering, the structure of resonance transitions excited by neutrino beams is in some cases strikingly different to that excited by virtual photons. Although on general grounds one may expect that a duality should also exist for weak structure functions, the details of how this manifests itself in neutrino scattering may be quite different from that observed in electron scattering.
JMU’s main role in the construction of the MINERvA detector is to align and test the photomultiplier tubes (PMT) that will be used for the neutrino detector. For this project our group build an alignment stand for the M64 Hamamatsu PMTs and aligned all the PMTs (~600) for the project. The project provided a wealth of opportunities for undergraduate students, from designing parts using AutoCAD and machining them in the shop, to assembling the stand and developing the data acquisition system. As an example, Andrew Borgquist, one of the students who worked with me during the summer of 2005 spent some time in designing the alignment stand. Below is a picture of the (almost) complete alignment setup.
Detector modules for the MINERvA experiment are being commissioned on the surface in preparation for installation in the neutrino beam. The first modules were installed in early 2009 and we expect complete construction of the detector early 2010. For more details on the first events detected by MINERvA see the following link.