Boyle, P.Juttner, A.Kenway, R.Sachrajda, C.Sasaki, S.Soni, A.Tweedie, R.Zanotti, J.2013-04-052013-04-052008Physical Review Letters, 2008; 100(14):141601:1-141601:40031-90071079-7114http://hdl.handle.net/2440/76512We present the first results for the K(sub)l3 form factor from simulations with 2+1 flavors of dynamical domain wall quarks. Combining our result, namely, f₊(0)=0.964(5) with the latest experimental results for K(sub)l3 decays leads to |V(sub)us|=0.2249(14), reducing the uncertaintity in this important parameter. For the O(p⁶) term in the chiral expansion we obtain Δf=-0.013(5).en© 2008 The American Physical SocietyRBC+UKQCD CollaborationsJournal article002012016410.1103/PhysRevLett.100.1416010002549409000162-s2.0-4214914923224130Zanotti, J. [0000-0002-3936-1597]