Subspace Least Square Approach for Drift Removal with Application to Herschel Data

We present a method to estimate and remove the baseline drift affecting the data produced by the two infrared imaging photometers onboard the ESA Herschel satellite, namely PACS and SPIRE. The method exploits a Least Square approach which is performed after that the signal component has been removed from the data by means of a projection into an appropriate subspace. We present the method, discuss its performance and implementation details and show that it is perfectly suited for Herschel data, for which it can ideally guarantee a complete drift removal.