https://doi.org/10.1140/epjc/s10052-020-8084-6
Regular Article - Theoretical Physics
Helicity form factors for 
process in the light-cone QCD sum rules approach
Department of Physics, Isfahan University of Technology, Isfahan, 84156-83111, Iran
* e-mail: samira.momeni@ph.iut.ac.ir
Received:
7
April
2020
Accepted:
23
May
2020
Published online:
17
June
2020
The helicity form factors of the 
with 
and 
are calculated in the light-cone sum rules approach, up to twist-3 distribution amplitudes of the axial vector meson A. In the helicity form factors parametrization the unitarity constraints are applied to the fitting parameters. In addition, the effects of the low-lying resonances are included in series expansions of aforementioned form factors. The properties of the semileptonic decays are studied by extending the form factors to the whole physical region of 
. For a better analysis, a comparison is also made between our results and the predictions obtained using transition form factors via LCSR, 3PSR and CLFQM methods.
© The Author(s), 2020
