Towards a general subtraction scheme for next-to-next-to-leading order QCD calculations
Raoul Rontsch (University of Milan)

With the measurements made by the experiments at the Large Hadron Collider becoming increasingly precise, it is vital that theoretical predictions reach the same level of precision, including for high multiplicity processes. This necessitates calculations to at least next-to-next-to-leading order (NNLO) in perturbative QCD. One of the challenges in computing such corrections is the treatment of infrared singularities, which arise at intermediate stages of the calculation. Although such singularities must cancel for physical observables, making this cancellation manifest while maintaining fully differential results is challenging, especially at NNLO where singularities from different kinematic limits may overlap in a complicated way. I will discuss the development of the nested soft-collinear subtraction scheme to regulate IR singularities and arrive at a finite physical result at NNLO. I will begin by outlining the method for the production of a color-singlet, and then discuss recent efforts to generalize it to arbitrary hadroproduction processes.