Center for Particles and Fields Seminar

Jacquelyn Noronha-Hostler, University of Houston

"Finding Missing Resonances using Lattice QCD"

4:00pm, RLM 5.114 (Note room change, this week only.)

Abstract: Lattice Quantum Chromodynamics has provided tremendous insight into high energy physics over the last ten years. Using first principles lattice calculations it was discovered that a cross-over phase transition exists from the Quark Gluon Plasma into a gas of hadrons, ab-initio calculations of the neutron-proton mass difference were performed, and the equation of state of our Universe from temperatures several hundreds of GeV to the MeV scale were calculated. The precision reached by recent lattice QCD results allows for the first time to investigate whether the measured hadronic spectrum is missing some additional states with nonzero strangeness, which are predicted by quark model calculations but have not yet been measured. This can be done by comparing some sensitive thermodynamic observables from lattice QCD to the predictions of the Hadron Resonance Gas model. We propose a set of specific observables, defined as linear combinations of conserved charge fluctuations, which allow to investigate this issue for baryons containing one or more strange quarks separately. Applications of these observables to isolate the multiplicity fluctuations of kaons from lattice QCD, and their comparison with the experimental results, are also discussed.