Speaker
Dr
Mikhail Mikhasenko
(HISKP, Universität Bonn)
Description
The nature of the recently discovered exotic charmonium-like states is still an open question.
The distinction between different underlying physical pictures often relies on an analysis of the resonance lineshape. In this context, it becomes crucial to know how exactly the amplitude should incorporate resonances and what uncertainties we expect from the formalism.
In the talk, I will discuss the construction of the reaction amplitude for the decay B -> Psi pi K, where the exotic Z(4430) signal was observed.
Two commonly-used recipes (the tensor formalism and the helicity formalism) provide frameworks to construct the partial-wave amplitude but do not lead to the same answer.
I will demonstrate and clarify the differences between these frameworks as well as their impact on the lineshapes. The approach based on analyticity and crossing symmetry which allows minimizing model dependence will be presented.
Primary author
Dr
Mikhail Mikhasenko
(HISKP, Universität Bonn)
