Search for the scalar glueball in a coupled channel amplitude analysis of J/psi decays with the BESIII experiment

ended

We propose to search for the scalar glueball, an exotic particle consisting entirely of the gauge bosons of the strong interaction, the gluons, using ten billion decays of the charmonium state J/psi recently accumulated with the BESIII experiment. The existence of glueballs has been predicted by the theory of the strong interaction, quantum chromodynamics (QCD), four decades ago. Yet, to date there has not been experimental evidence. Exploiting the unprecedented statistics of the BESIII experiment in combination with modern day high performance computing, we aim to uncover the glueball in a complex coupled channel amplitude analysis of J/psi decays into final states containing a vector particle and two pseudoscalar mesons. While radiative decays present a favourable, gluon-rich environment, massive vector mesons act as a flavour filter for an intermediate scalar resonance that subsequently decays to the two pseudoscalar mesons. Combining the information from these different decay channels in a coupled channel amplitude analysis will allow us to investigate the glueball components of the five established scalar states and by this the existence of the glueball itself. Our proposed work will, thus, address one of the pressing questions of QCD. To achieve our goal, we will develop a framework combining state-of-the-art amplitude analysis in K-matrix formalism with high performance computing on graphics processing units and will furthermore strongly collaborate with the Joint Physics Analysis Center hosted at Indiana University. The knowledge acquired during the outgoing phase, regarding the physics topic of the proposal, advanced aspects of amplitude analysis and a general purpose, high performance computing framework for such studies will be transferred back to Europe during the returning period. It will directly benefit ongoing research efforts at Johannes Gutenberg Universität Mainz as well as upcoming particle physics experiments like PANDA at FAIR hosted in Europe.