XVth Quark Confinement and the Hadron Spectrum

Weinberg compositeness criterion and extensions thereof

4 Aug 2022, 14:20

20m

AR Ø-110 (UiS)

Parallel Talk C: Heavy quarks Parallels Track C

Speaker

Dr Vadim Baru (Ruhr University Bochum)

Description

In the 1960’s Weinberg proposed a way to discriminate between molecular and compact
 near-threshold bound states in the weak-binding limit. We discuss a generalisation of this criterion 
which can be employed to characterise the compositeness of bound, virtual and resonance states [1]. 
In addition, the relevant modifications in the presence of coupled channels, 
isospin violations and unstable constituents are reviewed [2]. 
A clear recipe how to relate the scattering length and effective range extracted from a fit to experimental data 
to the ones to be used in the Weinberg criterion is provided.

[1] I.Matuschek, V.Baru, F.-K.Guo, and C.Hanhart, Eur. Phys.J.A 57 (2021) 3, 101

[2] V.Baru, X.K.Dong, M.L.Du, A.Filin, F.K.Guo, C.Hanhart, A.Nefediev, J.Nieves and Q.Wang, e-Print: 2110.07484 [hep-ph] to be published in Phys. Lett. B

Presentation materials

Compositness_Weinberg_VB.pdf