Abstract
We give a prescription for calculating the high-temperature expansion
of the thermal sunset integral to arbitrary order. We derive all terms
odd in \bm{T}𝐓,
and rederive previous results up to \bm{\mathcal{O}(T^0)}𝒪(𝐓0)
for both bosonic and fermionic thermal sunsets in dimensional
regularisation. We perform analytical and numerical cross-checks.
Intermediate steps involve integrals over three Bessel functions.
Funder
Grantová Agentura České Republiky
Univerzita Karlova v Praze
Vetenskapsrådet