Fig. 5: Measured results and calculated 14C production rates for the five spike candidates.
From: Patterns in solar activity over the first millennium CE

a 14-15 CE, (b) 553-554 CE, (c) 604-605 CE, d) 676-677 CE, and (e) 955-956 CE. The upper panels in each subplot show the measured Δ14C values with ± 1σ uncertainties (black dots and error bars) and the best fit from Gaussian Process Regression (blue lines). The red lines indicate the onset of each rise. The lower panels in each subplot present the Monte Carlo Markov Chain (posterior distribution draw) of production rates and Δ14C, computed using Gaussian Process Regression with control points.