Search for Excited Quark Resonances in the Photon $+$ Jet Invariant Mass Spectrum at 13 TeV

We present a search for excited quarks ( $q^{*}$ ) decaying into a photon and a hadronic jet in proton-proton collisions at $\sqrt{s} = 13\,$ TeV with the CMS experimentCMS experiment. High transverse momentum photons and jets are selected to search for a resonance peak in the continuous invariant mass distribution of the photon $+$ jet system. Excited quarksExcited quarks with mass ( ${\mathrm M}_{q^{*}}$ ) in the range, $1.0< {\mathrm M}_{q^{*}} < 4.37$ TeV, are excluded for coupling multiplier $f = 1.0$ at 95% confidence level. Results are also presented in terms of upper limits on cross section times branching ratio as a function of excited quark mass.