We measure the time-integrated CP asymmetry, A(CP), in D-0 -> pi(0)pi(0) decays reconstructed in e(+)e(-) -> c (c) over bar events collected by Belle II during 2019-2022. The data corresponds to an integrated luminosity of 428 fb(-1). The D-0 decays are required to originate from the flavor-conserving D*(+) -> D-0 pi(+) decay to determine the charm flavor at production time. Control samples of D-0 -> K-pi(+) decays, with or without an associated pion from a D*(+) decay, are used to correct for detection asymmetries. The result, A(CP) (D-0 -> pi(0)pi(0)) = (0.30 +/- 0.72 +/- 0.20)%, where the first uncertainty is statistical and the second systematic, is consistent with CP symmetry.
Measurement of the time-integrated CP asymmetry in D0 -> pi0 pi0 decays at Belle II
Bertacchi, V.;Bettarini, S.;Casarosa, G.;Corona, L.;Forti, F.;Massaccesi, L.;Rizzo, G.;Tenchini, F.;Trantou, F. F.;Zani, L.;
2025-01-01
Abstract
We measure the time-integrated CP asymmetry, A(CP), in D-0 -> pi(0)pi(0) decays reconstructed in e(+)e(-) -> c (c) over bar events collected by Belle II during 2019-2022. The data corresponds to an integrated luminosity of 428 fb(-1). The D-0 decays are required to originate from the flavor-conserving D*(+) -> D-0 pi(+) decay to determine the charm flavor at production time. Control samples of D-0 -> K-pi(+) decays, with or without an associated pion from a D*(+) decay, are used to correct for detection asymmetries. The result, A(CP) (D-0 -> pi(0)pi(0)) = (0.30 +/- 0.72 +/- 0.20)%, where the first uncertainty is statistical and the second systematic, is consistent with CP symmetry.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


