Asia-Pacific Symposium for Lattice Field Theory (APLAT 2020)

Study of the rho resonance using the HAL QCD method

4 Aug 2020, 15:20

20m

online

Hadron Spectroscopy and Interactions Hadron Spectroscopy and Interactions

Speaker

Yutaro Akahoshi (*) (Yukawa Institute for Theoretical Physics, Kyoto University)

Description

In this talk, we show the recent status of the rho resonance study in the HAL QCD method.
We investigate the I=1 two-pion potential at $m_{\pi }\approx 411$ MeV by using a new calculation strategy, namely the combination of three techniques: the one-end trick, the sequential propagator, and covariant approximation averaging (CAA).
Thanks to the new strategy, we determine the non-local I=1 two-pion potential at the next-leading-order of the derivative expansion for the first time and obtain the pole of the S-matrix corresponding to the rho resonance.
As regards the resonance parameters, our resonance mass is consistent with the previous study using the finite-volume method, but slightly larger decay width and coupling are obtained. We discuss possible origins of this difference.

Presentation materials

APLAT2020_YAkahoshi_rev1.pdf