Chiral loops in the isospin violating decays ofDs1(2460)+and

Svjetlana Fajfer

¹

,

Anita Prapotnik Brdnik

²

Abstract

, there is a tree-level contribution. We find that chiral loop contributions might be important in both cases. The calculated amplitudes are sensitive on the coupling constant describing the interaction of positive and negative parity heavy meson multiplets with the light pseudoscalars. The counterterms contributions are also present in the amplitudes Ds1(2460)We explore an experimentally known ratio of the decay widths for these two decay modes to estimate the size of counterterms contributions. We determine decay widths for both decay modes to be Γ(Ds1(2460)

Isospin violating decays of positive parity $$B_s$$ B s mesons in HM $$\chi $$ χ PT

“…6. Note that all diagrams with η meson in the loop give a vanishing contribution, as already discussed in [21]. The amplitude A can then be written as…”

“…Namely, the decay widths are very sensitive to the value of the coupling constant h and change significantly if the coupling constant h is varied within the error bars determined by the lattice studies [45]. Also, the counterterms are known only within a range of values in [21]. Let us note that the experimental measurement of the decay widths of the positive parity mesons D * s0 (2317) ± and D s1 (2460) ± , planned in the near future by various experiments, can lead to a more precise determination of the counter-terms [21].…”

“…Also, the counterterms are known only within a range of values in [21]. Let us note that the experimental measurement of the decay widths of the positive parity mesons D * s0 (2317) ± and D s1 (2460) ± , planned in the near future by various experiments, can lead to a more precise determination of the counter-terms [21]. Together with a detection and a measurement of the decay widths and the branching ratios of the strong decays of the positive parity (0 + , 1 + ) B s meson doublet, it will in principle allow one to extract the value of the coupling constant h exclusively from the D s and B s positive parity (0 + , 1 + ) doublet system.…”

“…In [21] we were able to constrain the size of this counter-term using the experimentally known ratio of the decay widths of the D s1 (2460) → D * s π and D s1 (2460) → D s ππ decay modes. The decay widths are also rather sensitive to the value of the coupling constant h as already noticed in [21], for the charm meson decays. The wave-function renormalization factor is responsible for this behavior.…”

“…On the other hand, authors of [10][11][12]22] used different approach based on the assumption that the decays proceed through the channels B * 0 s0 → B 0 s η → B 0 s π 0 and B 0 s1 → B * 0 s η → B * 0 s π 0 with the help of η-π mixing and predicted the partial decay widths in the range of 10-40 GeV. As already discussed in [20,21,25,26] chiral loop corrections play an important role in strong decays of D s positive parity states and their contribution to the strong decay modes can be as large as the effect of η-π mixing. Since π and ππ in the final state of these decays are having very small momenta, both decay modes are ideal to use heavy meson chiral perturbation theory (HMχ PT).…”