Document Type : Original Article


Department of Physics, Faculty of Science, Urmia University, Urmia, Iran


In this paper, the decay of the  meson into two vector mesons  and  is investigated.The first observation of the decay was reported in 2017 by LHCb collaboration, they have obtained the value of B () = (5. 01 ± 053 ± 0.27 ± 0.06)×10-4. In this study, the Feynman diagram of  decay is drawn based on the standard model. In particular this diagram shows that the decay consists of tree-exchange internal w-emission graph and penguin- suppressed graph. The coefficients of a2, a3, a5 and a7 are calculated in the NLO scale. The branching ratio is calculated using the QCD factorization method, numerical values in the NLO (at mb scale) scheme is 5.33×10-4, for which are in good agreement with the experimental results. The more calculations accuracy increases, the b quark mass scales come down corresponding to that. The best answer close to the experimental value is in NLO scheme at mb scale of QCDF approach.‎


  1. N Cabibbo, Rev. Lett. 10 (1963) 531.

  2. M Beneke and J Rohrer, Phys. B 774 (2007) 64.

  3. A Asadi and H Mehraban, International Journal of Modern Physics A (2016) 1650079.

  4. A Ali and C Group, Rev. D 57 (1998) 2996.

  5. B Mohammadi, International Journal of Modern Physics A 33 (2018) 1850044.

  6. M Tanabashi et al. (Particle Data Group), Rev. D 98 (2018) 030001.

  7. LHCb Collaboration (Roel Aaij (CERN) et al.), CERN-EP- 2017- 026, LHCB- PAPER- 2016- 056 (2017)

  8. A Ali and C Greub, Rev. D 57, (1997) 2996.

  9. Particle Data Group, Revised March 2020 by A Ceccucci (CERN), Z Ligeti (LBNL), and Y Sakai (KEK) (2020).

  10. HPQCD Collaboration, Rev. D 96 (2017) 074502.

  11. H Na, Ch J Monahan, Rev. D 86 (2012) 034506.

  12. H Yang Cheng and C Khiang Chua, Rev. D 80 (2009) 114008.

  13. R Aai, LHCb Collaboration, Rev. D 98 (2018) 071103.

تحت نظارت وف ایرانی