title: Measuring the photon polarization in B -->Kpipigamma.
abstract: We propose a way of measuring the photon polarization in radiative B decays into K resonance states decaying to Kpipi, which can test the standard model and probe new physics. The photon polarization is shown to be measured by the up-down asymmetry of the photon direction relative to the Kpipi decay plane in the K resonance rest frame. The integrated asymmetry in K1(1400)-->Kpipi, calculated to be 0.34 plus/minus 0.05 in the standard model, is measurable at currently operating B factories.
authors.affiliation: Department of Physics, Technion-Israel Institute of Technology, Technion City, 32000 Haifa, Israel.
authors.forename: Michael
authors.initials: M
authors.lastname: Gronau
authors.forename: Yuval
authors.initials: Y
authors.lastname: Grossman
authors.forename: Dan
authors.initials: D
authors.lastname: Pirjol
authors.forename: Anders
authors.initials: A
authors.lastname: Ryd