Fig. 3
a–f XMCD spectra predicted by the Gaussian process model with the equally separated initial data points (black filled circles in a) and maximum variance point sampling. Sm M4,5 XMCD spectra for a 30, b 35, c 40, d 50, e 60, and f 70 total data points. The black dashed and blue solid curves represent the true (experimental) spectrum and predicted spectrum by the GP model, respectively. The open circles represent observed data points. The red solid curves indicate the variance with the 95% confidence interval (±2σ) of the predicted spectrum. g–k Results for the adaptive design of the XMCD spectroscopy experiment where the initial data points had equal separation. g Orbital magnetic moment mo, h spin magnetic moment ms, and i their ratio mo/ms plotted as functions of the total data points. The red, blue, and green markers represent the methods for data point sampling: maximum variance (max. var.), random, and random sampling weighted by variance, respectively. The black solid and dashed lines represent the reference value and 5% deviations, respectively. j Total data points to convergence values of mo, ms, and mo/ms for different sampling methods. k Deviations of mo, ms, and mo/ms from their values in the conventional experiment
