Volume 363 - 37th International Symposium on Lattice Field Theory (LATTICE2019) - Main session
Vector current renormalisation in momentum subtraction schemes using the HISQ action
D. Hatton*, C. Davies, P. Lepage, A. Lytle  on behalf of HPQCD Collaboration
Full text: pdf
Pre-published on: December 05, 2019
Published on: August 27, 2020
Abstract
As the only lattice vector current that does not require renormalisation is the point-split conserved current it is convenient to have a robust, precise and computationally cheap methodology for the calculation of vector current renormalisation factors, $Z_V$. Momentum subtraction schemes, such as RI-SMOM, implemented nonperturbatively on the lattice provide such a method if it can be shown that the systematic errors, e.g. from condensates, are well controlled.

We present $Z_V$ calculations for the conserved current in both the RI-SMOM and RI$'$-MOM momentum subtraction schemes as well as local current renormalisation in the RI-SMOM scheme. By performing these calculations at various values of the momentum scale $\mu$ and different lattice spacings we can investigate the presence of power suppressed nonperturbative contributions and compare the results to expectations arising from the Ward-Takahashi identity. Our results show that the RI-SMOM scheme provides a well controlled determination of $Z_V$ but the standard RI$'$-MOM scheme does not.

We then present some preliminary uses of these $Z_V$ calculations in charm physics.
DOI: https://doi.org/10.22323/1.363.0016
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access