20.1 Mass

\[ E_1(\vec p=0)=M_{\infty}+P[1]\frac{e^{-M_{\infty} L}}{\sqrt{M_{\infty}L}} \] \(P[0]=M_{\infty}\)

\[\begin{gather} \chi^2/d.o.f.=1.87384 \\ P[0]=0.271209\pm (2.6e-05) \\ P[1]=0.34814\pm (0.19) \\ \end{gather}\] {\[\begin{gather} C=\begin{pmatrix} 6.6e-10& -0.851\\ -0.851& 0.035\\ \end{pmatrix} \end{gather}\]}