Spectrum of scalar and pseudoscalar glueballs from functional methods

Understand

We provide results for the spectrum of scalar and pseudoscalar glueballs in pure Yang-Mills theory using a parameter-free fully self-contained truncation of Dyson-Schwinger and Bethe-Salpeter equations.

• The only input, the scale, is fixed by comparison with lattice calculations.
• We obtain ground state masses of $1.9\,\text{GeV}$ and $2.6\,\text{GeV}$ for the scalar and pseudoscalar glueballs, respectively, and $2.6\,\text{GeV}$ and $3.9\,\text{GeV}$ for the corresponding first excited states.
• This is in very good quantitative agreement with available lattice results.