Observational systematics for galaxy clustering: transitioning from DES to LSST-DESC

One of the main cosmological probes that LSST-DESC will use to obtain cosmological constraints is the combination of galaxy clustering, cosmic shear and galaxy-galaxy lensing, resulting in the so-called 3x2pt probe. Given the astonishing amount of data that LSST will provide, statistical errors will shrink even lower than in previous stage surveys, such as DES, so systematic errors will become the main sources of uncertainty. Therefore it will be essential to know in detail the different sources of systematic effects and to correct for them appropriately in order to avoid significant biases on the results. In this sense, galaxy clustering measurements are not an exception to this problem, with observational systematics being of particular relevance. In this contribution we present how we can apply the different methodologies developed during DES-Y3 and Y6 to the treatment of the observational systematics in LSST-DESC's future galaxy clustering measurements. We will also discuss the additional methods that we are currently studying at the IFT.