Senior Matt Wussow, Dr. Nathan Grau Published in Scientific Journal

A paper by Matt Wussow, a senior physics and mathematics major and a native of Eden Prairie, Minn., and Dr. Nathan Grau, visiting assistant professor of physics, titled "Determination of the Quark Content of Scalar Mesons Using Hydrodynamical Flow in Heavy Ion Collisions" was recently published in Physical Review C, the nuclear physics journal of the American Physical Society. The paper is a summary of their work performed over the last year. The paper outlines a measurement using relativistic nuclear collisions to confirm the existence of theoretically predicted exotic particles that have not yet been experimentally observed.

Normal particles in nature, like the proton and neutron, are made of particles called quarks. Each proton and neutron is composed of three of these quarks. The theory of the strong nuclear force, which explains the structure of the proton and the existence of nuclei, allow for particles that can be made of four quarks instead of three. There are several particles that could possibly have a four-quark structure but there has yet to be conclusive confirmation of this. The paper puts forth an idea to measure two of these particles called the a0(980) and f0(980) in nuclear collisions. Their behavior in these collisions will allow a definitive measure of the number of quarks they are made from. Plans for the future include using data from the PHENIX experiment to attempt to make the suggested measurement and to look at additional particles that could be these exotic four-quark states.

IMAGE ABOVE: An example relativistic nuclear collision event in the PHENIX detector. The lines indicate particles from the collision that are detected. These types of collisions are being used to search for the tetraquark particles.