Journal Article

Model-independent measurement of the CKM angle γ using B0→DK∗0 decays with D→K0Sπ+π− and K0SK+K

Renaudin, V., Beaucourt, L., Wormser, G., Leroy, O., Chefdeville, M., Kanso, W., Grabalosa Gándara, M., Serrano, J., Barsuk, S., Li, Y., De Bruyn, K., Deschamps, O., Aaij, R., Decamp, D., Henrard, Pierre, Kozeiha, M., Lees, J.-P., Fleuret, F., Mordà, A., Tsaregorodtsev, A., Marchand, J.-F., Mancinelli, G., Schune, M.-H., Tayduganov, A., Cogan, J., Gazzoni, G., Minard, M.-N., Pietrzyk, B., Lefèvre, R., Lefrançois, J., Quagliani, R., Vallier, A., Machefert, F., Perret, P., Baalouch, M., Viaud, B., Maratas, J., El Rifai, I., Aslanides, E., Tournefier, E., Hoballah, M., Ajaltouni, Z.J., Akar, S., Tisserand, V., Manca, G., Niess, V., Cogneras, E., Ghez, P., Massacrier, L.M., Amhis, Y., t'Jampens, S., Monteil, S., Robbe, P., Legac, R., Déléage, N., Kochebina, O., Martin, M.

2016

Overview

A binned Dalitz plot analysis of the decays B0→DK∗0, with D→K0Sπ+π− and K0SK+K−, is performed to measure the observables x± and y±, which are related to the CKM angle γ and the hadronic parameters of the decays. The D decay strong phase variation over the Dalitz plot is taken from measurements performed at the CLEO-c experiment, making the analysis independent of the D decay model. With a sample of proton-proton collision data, corresponding to an integrated luminosity of 3.0fb−1, collected by the LHCb experiment, the values of the CP violation parameters are found to be x+=0.05±0.35±0.02, x−=−0.31±0.20±0.04, y+=−0.81±0.28±0.06 and y−=0.31±0.21±0.05, where the first uncertainties are statistical and the second systematic. These observables correspond to values γ = (71±20)∘, rB0=0.56±0.17 and δB0=(204+21−20)∘. The parameters rB0 and δB0 are the magnitude ratio and strong phase difference between the suppressed and favoured B0 decay amplitudes, and have been measured in a region of ±50 MeV/c2 around the K∗(892)0 mass and with the magnitude of the cosine of the K∗(892)0 helicity angle larger than 0.4.

• Publisher: Springer
• Subject: High Energy Physics - Experiment / Physics