QCD thermodynamics with dynamical chiral fermions

We discuss properties of thermal Quantum Chromodynamics obtained by means of lattice simulations with overlap fermions. This fermion discretisation preserves chiral symmetry at finite lattice spacing. We present details of the formulation and results for the chiral observables. We determine the topological susceptibility from simulations at fixed global topological charge based on the slab method. Using the measured values of the topological susceptibility we sum the chiral observables over all topological sectors. The volume dependence of the chiral susceptibility is in agreement with the crossover nature of the thermal QCD phase transition. Additionally we discuss the spectrum of the overlap Dirac operator and its volume and temperature dependence. Presented results are obtained at the temporal lattice extent N_t = 8.