Search for resonances in the mass distribution of jet pairs with one or two jets identified as $b$-jets with the ATLAS detector with 2015 and 2016 data

Searches for resonances in the dijet invariant mass spectrum with one or two jets identified as $b$-jets are presented. The dataset consists of an integrated luminosity of 13.3 fb$^{-1}$ of proton--proton collisions with a centre-of-mass energy of $\sqrt s = 13$ TeV recorded in 2015 and 2016 by the ATLAS detector at the Large Hadron Collider. No evidence of new phenomena is found in the data. Excited $b^*$ quarks with masses up to 2.3 TeV at leading-order in QCD are excluded at 95% credibility level. Contributions of a Gaussian signal shape with effective cross sections ranging from approximately 0.2 to 0.001 pb are also excluded in the mass range 1.4--5.5 TeV.