Search for low-mass resonances decaying into two jets and produced in association with a photon using pp collisions at √s = 13 TeV with the ATLAS detector

De Castro , S.; Fabbri , L.; Gabrielli , A.; Rinaldi , L.; Semprini Cesari , N.; Sioli , M.; Villa , M.; Zoccoli , A.; Bellagamba , L.; Boscherini , D.; Bruni , A.; Bruni , G.; D’Amen , G.; Giacobbe , B.; Polini , A.; Sbarra , C.; Sidoti , A.; Spighi , R.; Franchini , M.; Mengarelli , A.; Romano , M.; Valentinetti , S.; Alberghi , G. L.; Biondi , S.; Fabbri , F.; Lasagni Manghi , F; Massa , L.; Ucchielli , G.; Vittori , C.; Alfonsi , F:; Cabras , G.; Cervelli , A.; Giangiacomi , N.; Negrini , M.; ATLAS collaboration

doi:10.1016/j.physletb.2019.03.067

A search is performed for localised excesses in dijet mass distributions of low-dijet-mass events produced in association with a high transverse energy photon. The search uses up to 79.8fb−1of LHC proton–proton collisions collected by the ATLAS experiment at a centre-of-mass energy of 13TeV during 2015–2017. Two variants are presented: one which makes no jet flavour requirements and one which requires both jets to be tagged as b-jets. The observed mass distributions are consistent with multi-jet processes in the Standard Model. The data are used to set upper limits on the production cross-section for a benchmark Zmodel and, separately, on generic Gaussian-shape contributions to the mass distributions, extending the current ATLAS constraints on dijet resonances to the mass range between 225 and 1100GeV

De Castro, S., Fabbri, L., Gabrielli, A., Rinaldi, L., Semprini Cesari, N., Sioli, M., et al. (2019). Search for low-mass resonances decaying into two jets and produced in association with a photon using pp collisions at √s = 13 TeV with the ATLAS detector. PHYSICS LETTERS. SECTION B, 795, 56-75 [10.1016/j.physletb.2019.03.067].