Eur. Phys. J. A (2020) 56: 25
https://doi.org/10.1140/epja/s10050-020-00041-y

Letter

Pseudoscalar glueball mass: a window on three-gluon interactions

¹ Federal Institute of Education, Science and Technology of Piauí, Picos, Piauí, 64605-500, Brazil
² University of Campinas-UNICAMP, Institute of Physics “Gleb Wataghin”, Campinas, São Paulo, 13083-859, Brazil
³ Department of Theoretical Physics and IFIC, University of Valencia and CSIC, 46100, Valencia, Spain
⁴ School of Physics, Nanjing University, Nanjing, 210093, Jiangsu, China
⁵ Institute for Nonperturbative Physics, Nanjing University, Nanjing, 210093, Jiangsu, China
⁶ College of Science, Nanjing University of Posts and Telecommunications, Nanjing, 210023, China

^* e-mail: cdroberts@nju.edu.cn

Received: 28 November 2019
Accepted: 6 December 2019
Published online: 28 January 2020

Abstract

In pure-glue QCD, gluon–gluon scattering in the channel is described by a very simple equation, especially if one considers just the leading contribution to the scattering kernel. Of all components in this kernel, only the three-gluon vertex, , is poorly constrained by contemporary analyses; hence, calculations of glueball properties serve as a clear window onto the character and form of . This is important given that many modern calculations of predict the appearance of an infrared suppression in the scalar function which comes to modulate the bare vertex after the nonperturbative resummation of interactions. Such behaviour is a peculiar prediction; but we find that the suppression is essential if one is to achieve agreement with lattice-QCD predictions for the glueball mass. Hence, it is likely that this novel feature of is real and has observable implications for the spectrum, decays and interactions of all QCD bound-states.