Resonances from lattice QCD
Thomas Jefferson National Accelerator Facility, 12000 Jefferson Avenue, Newport News, VA 23606, USA
2 Department of Physics, Old Dominion University, Norfolk, VA 23529, USA
Published online: 26 March 2018
The spectrum of hadron is mainly composed as shortly-lived states (resonance) that decay onto two or more hadrons. These resonances play an important role in a variety of phenomenologically significant processes. In this talk, I give an overview on the present status of a rigorous program for studying of resonances and their properties using lattice QCD. I explain the formalism needed for extracting resonant amplitudes from the finite-volume spectra. From these one can extract the masses and widths of resonances. I present some recent examples that illustrate the power of these ideas. I then explain similar formalism that allows for the determination of resonant electroweak amplitudes from finite-volume matrix elements. I use the recent calculation of the πγ* → ππ amplitude as an example illustrating the power of this formalism. From such amplitudes one can determine transition form factors of resonances. I close by reviewing on-going efforts to generalize these ideas to increasingly complex reactions and I then give a outlook of the field.
Thanks his colleagues and collaborators for their continuous support. RAB would also like to thank his colleagues from the Hadron Spectrum Collaboration for granting permission to share results obtained in collaboration with them. RAB acknowledges support from U.S. Department of Energy contract DE-AC05-06OR23177, under which Jefferson Science Associates, LLC, manages and operates Jefferson Lab.
© The Authors, published by EDP Sciences, 2018
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