Measurements of $t\bar{t}$ differential cross-sections in the all-hadronic channel with the ATLAS detector using highly boosted top quarks in $pp$ collisions at $\sqrt{s}=13$ TeV

A measurement of the boosted top quark differential cross-section in 13 TeV $pp$ collisions in the all-hadronic decay modes is presented. The $t\bar{t}$ process is measured by requiring two top-quark candidates, one with $p_{\rm T} > 500$ GeV and a second with $p_{\rm T} > 350$ GeV, with each candidate reconstructed as an antikT jet with radius parameter $R=1.0$. The top quark candidates are separated from the multijet background using the jet substructure and the presence of a $b$-quark tag in each jet. The observed kinematic distributions are unfolded to recover the differential cross-sections in a limited phase-space region and compared with Standard Model predictions.