Effect of K0 - K0 mixing on CP and CPT violations in B±c→ B±KS,L0 decays

The large data sample of the B-c meson collected at the LHC experiment and the HL-LHC experiment provides us the opportunity to study the B-c decays and the related physics. In this paper, we investigate the effect of K-0 - K-0 mixing on the branching ratios, CP violations and CPT violations in the B-c(+/-) -> B-+/- K-S,L(0) decays. We find that some of the B-c(+/-) -> (BKS,L0)-K-+/- f(B +/-)f(KS,L)(0) decay chains have large branching ratios, whose maximum value can exceed the order of 10(-6), the minimum number of B-c(+/-) events times efficiency for observing the decays at three standard deviations (3 sigma) level is about 10(6). We study the CP asymmetries in the B-c(+/-) -> B-+/- K-S,L(0) decays and find that the CP asymmetries can exceed the order of 10(-3), which are dominated by K-0 - K-0 mixing. We give the most promising processes to observe the CP violations and the ranges of the numbers of B-c(+/-) events-times-efficiency needed to observe the CP asymmetries at a significance of 3 sigma in these decays. We investigate the possibility to constraint the CPT violation parameter z in the B-c(+/-)-> B-+/- K(S,L)(0)f(B +/-)f(KS,L)(0) decays and give the most promising processes to constraint the parameter z.