U-Channel

$\textbf{\underline{Navigation}}$

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u-Channel

The u quantity is does not have a clear cut interpretation like the s and t channels

$u \equiv \left({\mathbf P_1^*}- {\mathbf P_2^{'*}}\right)^2=\left({\mathbf P_2^*}- {\mathbf P_1^{'*}}\right)^2$

$u \equiv\left({\mathbf P_1^*}- {\mathbf P_2^{'*}}\right)^2$

$u \equiv \mathbf P_1^{*2}-2 \mathbf P_1^* \mathbf P_2^{'*}+ \mathbf P_2^{'*2}$

$u \equiv 2m_1^2-2E_1^*E_2^{'*}+2 \vec p \ _1^* \vec p \ _2^{'*}$

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$\textbf{\underline{Navigation}}$

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