Amplitude analysis of Bs0 → KS0K±π∓ decays

Abstract

The first untagged decay-time-integrated amplitude analysis of Bs0 → KS0K±π∓ decays is performed using a sample corresponding to 3.0 fb−1 of pp collision data recorded with the LHCb detector during 2011 and 2012. The data are described with an amplitude model that contains contributions from the intermediate resonances K*(892)0,+, K2*(1430)0,+ and K0*(1430)0,+, and their charge conjugates. Measurements of the branching fractions of the decay modes Bs0 → K*(892)±K∓ and Bs0→K*—8920K0—$$ {B}_s^0\to \overset{\left(\hbox{---} \right)}{K^{}}{(892)}^0\overset{\left(\hbox{---} \right)}{K^0} $$ are in agreement with, and more precise than, previous results. The decays Bs0 → K0(1430)±K∓ and Bs0→K0*—14300K0—$$ {B}_s^0\to \overset{\left(\hbox{---} \right)}{K_0^{*}}{(1430)}^0\overset{\left(\hbox{---} \right)}{K^0} $$ are observed for the first time, each with significance over 10 standard deviations.