|
Bayar, M., Feijoo, A., & Oset, E. (2023). X(3960) seen in Ds plus Ds- as the X(3930) state seen in D plus D. Phys. Rev. D, 107(3), 034007–5pp.
Abstract: We perform a calculation of the interaction of the D over bar D, Ds over bar Ds coupled channels and find two bound states, one coupling to DD over bar and another one at higher energies coupling mostly to D+s D-s . We identify this latter state with the X0(3930) seen in the D+D- mass distribution in the B+ -D+D-K+ decay, and also show that it produces an enhancement of the D+s D-s mass distribution close to threshold which is compatible with the recent LHCb observation in the B+ -D+s D-s K+ decay which has been identified as a new state, X0(3960).
|
|
|
Bayar, M., Molina, R., Oset, E., Liu, M. Z., & Geng, L. S. (2024). Subtleties in triangle loops for Ds+ → ρ+ η → π+ π0 η in a0(980) production. Phys. Rev. D, 109(7), 076027–7pp.
Abstract: We address a general problem in the evaluation of triangle loops stemming from the consideration of the range of the interaction involved in some of the vertices, as well as the energy dependence of the width of some unstable particles in the loop. We find sizeable corrections from both effects. We apply that to a loop relevant to the D + s -> pi + pi 0 eta decay, and find reductions of about a factor of 4 in the mass distribution of invariant mass of the pi eta in the region of the a 0 ( 980 ) . The method used is based on the explicit analytical evaluation of the q 0 integration in the d 4 q loop integration, using Cauchy 's residues method, which at the same time offers an insight on the convergence of the integrals and the effect of form factors and cutoffs.
|
|
|
Duan, M. Y., Bayar, M., & Oset, E. (2024). Precise determination of the ηΛ scattering length and effective range and relationship to the Λ(1670) resonance. Phys. Lett. B, 857, 139003–5pp.
Abstract: We use the Belle data on the K(-)p mass distribution of the Lambda(+)(c)-> pK(-)pi(+) reaction near the eta Lambda threshold to determine the eta Lambda scattering length and effective range. We show that from these data alone we can determine the value of a with better precision than so far determined, and the value of r(0) for the first time. The addition of the K(-)p ->eta Lambda data allows us to improve the precision of these magnitudes, with errors smaller than 15%. We also determine with high precision the pole position of the Lambda(1670).
|
|