PT Journal AU ATLAS Collaboration (Aaboud, Mea Alvarez Piqueras, D Aparisi Pozo, JA Bailey, AJ Barranco Navarro, L Cabrera Urban, S Castillo, FL Castillo Gimenez, V Cerda Alberich, L Costa, MJ Escobar, C Estrada Pastor, O Ferrer, A Fiorini, L Fullana Torregrosa, E Fuster, J Garcia, C Garcia Navarro, JE Gonzalez de la Hoz, S Gonzalvo Rodriguez, GR Higon-Rodriguez, E Jimenez Pena, J Lacasta, C Lozano Bahilo, JJ Madaffari, D Mamuzic, J Marti-Garcia, S Melini, D MiƱano, M Mitsou, VA Rodriguez Bosca, S Rodriguez Rodriguez, D Ruiz-Martinez, A Salt, J Santra, A Soldevila, U Sanchez, J Valero, A Valls Ferrer, JA Vos, M TI Search for long-lived neutral particles in pp collisions at root s=13 TeV that decay into displaced hadronic jets in the ATLAS calorimeter SO European Physical Journal C JI Eur. Phys. J. C PY 2019 BP 481 - 31pp VL 79 IS 6 DI 10.1140/epjc/s10052-019-6962-6 LA English AB This paper describes a search for pairs of neutral, long-lived particles decaying in the ATLAS calorimeter. Long-lived particles occur in many extensions to the Standard Model and may elude searches for new promptly decaying particles. The analysis considers neutral, long-lived scalars with masses between 5 and 400 GeV, produced from decays of heavy bosons with masses between 125 and 1000 GeV, where the long-lived scalars decay into Standard Model fermions. The analysis uses either 10.8 fb-1 of data (depending on the trigger) recorded in 2016 at the LHC with the ATLAS detector in proton-proton collisions at a centre-of-mass energy of 13 TeV. No significant excess is observed, and limits are reported on the production cross section times branching ratio as a function of the proper decay length of the long-lived particles. ER