un 2 00 0 ITERATIVE MAP - MAKING FOR SCANNING EXPERIMENTS
نویسنده
چکیده
The map-making problem for CMB anisotropy measurements was first considered in the context of the COBE-DMR mission 3,5. It was further extended to quick algorithms for differential measurements 6 taking into account 1/f noise 7. Given the size of the upcoming datasets (≥ 106 pixels for MAP) it is essential that the map-making algorithm remains quick (typically O(nd logLN ) where nd is the number of time-samples, and LN the effective noise-filter length). Another related question, which has been pioneered by1, is how to determine the noise statistical properties from the data itself. We present a map-making method based on Wright’s fast algorithm to compute iteratively a minimum variance map together with an estimate of the detector noise power spectrum which is needed to compute unbiased power spectrum estimators of the cosmological signal.
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