V (t) = V_{0}e^{−(t−t_{0})^{2}/2σ^{2}}

σ = \frac{FWHM}{2.35} = 0.426

K^{2} = ∑_{i} (data_{i} − model_{i})^{2}

f(A, t) = ∑_{i} (data_{i} − Ae^{−(t_{i}−t)^{2}/2σ^{2}})^{2}

∇f = \frac{∂f}{∂A}î + \frac{∂f}{∂t} ĵ

\frac{∂f}{∂A} ≃ \frac{f(A_{1} + δA, t_{1}) − f(A_{1} − δA, t_{1})}{2 δA}

\frac{∂f}{∂t} ≃ \frac{f(A_{1}, t_{1} + δt) − f(A_{1}, t_{1} − δt)}{2 δt}

f(4 + 0.5, 7) = 108

f(4 − 0.5, 7) = 94

f(4, 7 + 0.5) = 4

f(4, 7 − 0.5) = 224

ĥ = − (\frac{14}{\sqrt{14^{2} + 220^{2}}} ) î + (\frac{220}{\sqrt{14^{2} + 220^{2}}} ) ĵ

new (A, t) = (A, t) + stepsize ∗ ĥ