Fig. 3: Values of the normalized cost function around the best-performing point found by BBO.
From: Batch Bayesian optimization of attosecond betatron pulses from laser wakefield acceleration
The values are shown for a) varying du, fixed \({d}_{{{\rm{s}}}}={d}_{{{\rm{s}}}}^{{{\rm{opt}}}}\), \({n}_{{{\rm{p}}}}={n}_{{{\rm{p}}}}^{{{\rm{opt}}}}\), b) varying ds, fixed \({d}_{{{\rm{u}}}}={d}_{{{\rm{u}}}}^{{{\rm{opt}}}}\), \({n}_{{{\rm{p}}}}={n}_{{{\rm{p}}}}^{{{\rm{opt}}}}\), and c) varying np/n0, fixed \({d}_{{{\rm{u}}}}={d}_{{{\rm{u}}}}^{{{\rm{opt}}}}\), \({d}_{{{\rm{s}}}}={d}_{{{\rm{s}}}}^{{{\rm{opt}}}}\). The normalized cost function C/Cref is shown with orange lines and circular markers at the evaluated points. The normalized model prediction \(\widehat{C}/{C}^{{{\rm{ref}}}}\) for N = 8 from the final (8th) iteration, is shown with blue lines with crosses at evaluated points. Colored shaded regions indicate the area within predicted standard deviation \({\sigma }_{\widehat{C}}\). The large black circle marks the best-performing case.
