The 33rd International Symposium on Lattice Field Theory (Lattice 2015)

SU(3)-breaking effects and induced second-class form factors in hyperon beta decays from 2+1 flavor lattice QCD

15 Jul 2015, 16:50

20m

403 (Kobe International Conference Center)

Talk Hadron Structure Hadron Structure

Speaker

Prof. Shoichi Sasaki (Tohoku University)

Description

We discuss the effects of SU(3) symmetry breaking measured in hyperon semileptonic decays from fully dynamical lattice QCD. Our calculations are carried out with gauge configurations generated by the RBC and UKQCD collaborations with (2+1)-flavors of dynamical domain-wall fermions and the Iwasaki gauge action at two couplings, ¥beta$=2.13and2.25.Wehaveestimatedthevalueofthehyperonvectorcouplings$f_1(0)$withanaccuracyoflessthanonepercent.Wethenfindthatlatticeresultsof$f_1(0)$combinedwiththebestestimateof$|V_{us}|$withimposingCKMunitarityareslightlydeviatedfromtheexperimentalresultof$|V_{us}f_1(0)|$for$¥Sigma ¥rightarrow N$decay.Thisdiscrepancycanbeattributedtoanassumptionmadeintheexperimentalanalysison$|V_{us}f_1(0)|$,wheretheinducedsecond-classformfactor$g_2$issettobezero.Wewillthereforereportonthismatterandshowthepreliminaryresultsof$g_2(0)$ evaluated in both indirect and direct ways.

Presentation materials

Slides

Lattice2015_talk_v2.pdf