Physics professor receives NSF support to study the fundamental structure of nucleons

Professor Phil Cole, chair of the Physics Department, has been awarded $225,000 from the National Science Foundation.  The three-year grant entitled, “Probing the Structure of Nucleons in Omega Meson Electroproduction,” also provides funding for undergraduate students to work at two nuclear physics laboratories, Jefferson Lab in Newport News, VA and at the BGO-OD Experiment at the University of Bonn in

Germany.

“Our understanding on the fundamental building blocks of atoms has come a long way, but we still have a long way to go,” said Cole. “Scientists discovered the electron near the very end of the 19th century, in 1911 the Rutherford Experiment established the existence of atomic nuclei, not much later, the proton was identified in 1917 and it was only until 1932 that the neutron was discovered, incidentally in Rutherford’s lab. We now know that the nucleus is made up of protons and neutrons bound together by some nuclear force.”

In recent history, even smaller sub-particles called quarks were discovered at a Stanford experiment in 1968. These particles, protons and neutrons, are held together by very strong nuclear forces that act within extremely tiny distances.   

“For example, the force tending to push two protons apart in the nucleus is several pounds,” said Cole. “Something really strong must be binding them together; hence the name strong force.”

Since that time physics has made significant strides explaining how matter and energy interrelate at the particle level. All chemical and biological action derives from the reorganization and energy exchanges of atoms. The interplay of energy, including using light as an energy source, and matter is the very stuff of life.

According to Cole, understanding how the strong force is generated inside the nucleus is one of the greatest intellectual challenges facing nuclear physicists today because the spatial scale of the force is so small and that so very little is really known about the internal structure of protons and neutrons.

“The strong force inside the proton is mediated by the exchange of particles known as gluons,” said Cole. “Our knowledge of how protons and neutrons are constructed from their quark and gluon constituents, however, is not well understood. Some of the interactions of these particles and their energy transitions take place for the briefest of moments – on the order of a trillionth of a trillionth of a second (10−24 s). During these interactions, another type of particles called mesons are produced.   Mesons are the force particles that bind protons and neutrons together in the nucleus and they themselves – the meson are made up of quarks and gluons.  Understanding the types of mesons produced and how they are distributed in space will provide key insights to the structure of the proton and neutron in an atom’s nucleus.” 

Cole will use the NSF support to engage Lamar undergraduate students in a unique learning experience to help answer the very basic question on how matter is made.

Cole often teaches modern physics, and his work in experimental nuclear physics is a direct application of this course.  Additionally, he leads a study abroad program at the University of Bonn where students can take a four-week course titled, “Experimental Nuclear Physics on the Rhine.” (Click under Physics Institute to see more.) 

“There is no other course like this in the world,” said Cole. “The students learn all the theoretical and experimental basics of nuclear physics; they even collect their own data with a world-class particle accelerator in Germany.”

Cole was a Fulbright Professor at the University of Bonn in 2014/2015 and has published an account of his work in the online “German Fulbright journal,” which explains the nontechnical details of this science to the general public.