... Each on is 50 six second integrations followed by 50 six second off positions. ... For each freq channel do a linear fit along the time direction throwing out any points that are outliers (fit residuals greater than 3 sigma). ... A baseline is then removed from the final spectra (linear polynomial and second order harmonic). ... The rms is then computed over the points used in the fit. ... The quoted rms is for the points that were used in the baseline fit. ...