  A search for a heavy resonance decaying to a top quark and a W boson in the
fully hadronic final state is presented. The analysis is performed using data
from proton-proton collisions at a center-of-mass energy of 13 TeV,
corresponding to an integrated luminosity of 137 fb$^{-1}$ recorded by the CMS
experiment at the LHC. The search is focused on heavy resonances, where the
decay products of each top quark or W boson are expected to be reconstructed as
a single, large-radius jet with a distinct substructure. The production of an
excited bottom quark, b*, is used as a benchmark when setting limits on the
cross section for a heavy resonance decaying to a top quark and a W boson. The
hypotheses of b* quarks with left-handed, right-handed, and vector-like
chiralities are excluded at 95% confidence level for masses below 2.6, 2.8, and
3.1 TeV, respectively. These are the most stringent limits on the b* quark mass
to date, extending the previous best limits by almost a factor of two.
