The heavy-ion program at the Large Hadron Collider has been commenced in November 2010 by three experiments including ATLAS, a multipurpose detector. It was originally constructed to study high-energy proton-proton collisions but now it also proves to be an excellent tool for studying nuclear interactions. In these proceedings results from the lead-lead run at root s(NN) = 2.76 TeV based on the minimum-bias data sample are reviewed. In particular, an observation of the centrality-dependent dijet asymmetry is reported. Also a centrality-dependent suppression in the yield of J/psi mesons decaying to mu(+)mu(-) pairs is discussed along with an observation of the Z boson production. These evidences may bring new insight to the dynamics of heavy-ion collisions.

The semiconductor tracker (SCT) is one of the tracking systems for charged particles in the ATLAS detector. It consists of 4088 silicon strip sensor modules. During Run 2 (2015-2018) the Large Hadron Collider delivered an integrated luminosity of 156 fb−1 to the ATLAS experiment at a centre-of-mass proton-proton collision energy of 13 TeV. The instantaneous luminosity and pile-up conditions were far in excess of those assumed in the original design of the SCT detector. Due to improvements to the data acquisition system, the SCT operated stably throughout Run 2. It was available for 99.9% of the integrated luminosity and achieved a data-quality efficiency of 99.85%. Detailed studies have been made of the leakage current in SCT modules and the evolution of the full depletion voltage, which are used to study the impact of radiation damage to the modules.