Jul 24 – 30, 2016
Highfield Campus, University of Southampton
Europe/London timezone

Hadron Matrix Elements and the Feynman-Hellman Theorem

Jul 25, 2016, 4:45 PM
Building B2a Room 2077 (Highfield Campus, University of Southampton)

Building B2a Room 2077

Highfield Campus, University of Southampton

Talk Hadron Structure Hadron Structure


Andre Walker-Loud (LBNL)


Motivated by the Feynman-Hellman Theorem, we develop an improved method for computing matrix elements of external currents utilizing only two-point correlation functions. The contamination from excited states is shown to be Euclidean-time dependent allowing for a significantly improved ability to reliably determine and control the systematics. We demonstrate the utility of our method with a calculation of the nucleon axial-charge, performed at a single lattice spacing and a moderate unphysical pion mass. The Feynman-Hellman Theorem can be derived from the long Euclidean-time limit of correlation functions determined with functional derivatives of the partition function. This elucidates the generic applicability of our new method: one can determine matrix elements of any external current by computing only two-point correlation functions, including non-zero momentum transfer and flavor-changing matrix elements.

Primary author


Dr Chris Bouchard (William & Mary) Prof. Kostas Orginos (College of William and Mary/JLAB) Dr Thorsten Kurth (LBNL)

Presentation materials