APS Division of Nuclear Physics

The Division of Nuclear Physics (DNP) is comprised of scientists and educators who study fundamental problems related to the nature of matter. Nuclear scientists probe the properties of nuclei and nuclear matter and the interactions of their ultimate constituents — quarks and gluons. They also address interdisciplinary questions: the basis of fundamental symmetries in nature, the first moments of the universe, the origin of the elements, education, and the application of nuclei and nuclear techniques to meet societal needs including medical diagnoses and treatment, energy, advanced materials, and Homeland Security. DNP interests have significant overlap with other APS Divisions, Topical Groups and Forums.

Recent advances in quarkonia from RHIC

Scientists from over 26 countries have been working diligently at the relativistic heavy ion collider (RHIC) accelerator facility at Brookhaven National laboratory (BNL) to quantify the properties of the quark gluon plasma produced in ultra-relativistic heavy ion collisions. The idea that charmonium states should melt (or never form) in hot dense matter was originally proposed by Matsui and Satz [1] and may provide a model dependent method for extracting the temperature of the plasma. The idea is that the color screening length in a deconfined plasma of quarks and gluons would be smaller than the binding radius of a charm anti-charm pair. The pair, would be screened and therefore not able to bind (much like Debye screening in electromagnetic plasmas). In addition the different states have different binding radii and thus melt at different temperatures, a process termed "sequential melting". More