Difference between revisions of "Talk:DWBA"
KevinYager (talk | contribs) (Created page with "<math> \begin{align} I_d(q_{z}) & = | T_i T_f F(+Q_{z1}) + T_i R_f F(-Q_{z2}) + R_i T_f F(+Q_{z2}) + R_i R_f F(-Q_{z1}) | ^{2} \\ & \begin{align} ...") |
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+ | ==DWBA Equation in thin film== | ||
+ | Using the notation <math>T_i = T(\alpha_i)</math> for compactness, the DWBA equation inside a thin film can be written: | ||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | I_d(q_{z}) & = | | ||
+ | T_i T_f F(+Q_{z1}) | ||
+ | + T_i R_f F(-Q_{z2}) | ||
+ | + R_i T_f F(+Q_{z2}) | ||
+ | + R_i R_f F(-Q_{z1}) | ^{2} \\ | ||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | ==Expansion (incorrect)== | ||
+ | '''WARNING: This incorrectly ignores the complex components.''' | ||
+ | ===Terms=== | ||
+ | If one expands the <math>|...|^2</math> of the DWBA, one obtains 16 terms: | ||
+ | |||
+ | <math> | ||
+ | |||
+ | \begin{matrix} | ||
+ | & (T_i T_f) & (T_i R_f) & (R_i T_f) & (R_i R_f) \\ | ||
+ | (T_i T_f) & T_i^2T_f^2 & T_i^2 T_f R_f & T_iR_iT_f^2 & T_iR_iT_fR_f \\ | ||
+ | (T_i R_f) & T_i^2T_fR_f & T_i^2R_f^2 & T_iR_iT_fR_f & T_iR_iR_f^2 \\ | ||
+ | (R_i T_f) & T_iR_iT_f^2 & T_iR_iT_fR_f & R_i^2T_f^2 & R_i^2T_fR_f \\ | ||
+ | (R_i R_f) & T_iR_iT_fR_f & T_iR_iR_f^2 & R_i^2T_fR_f & R_i^2R_f^2 \\ | ||
+ | \end{matrix} | ||
+ | |||
+ | </math> | ||
+ | |||
+ | ===Equation=== | ||
+ | The equation can thus be expanded as: | ||
+ | |||
<math> | <math> | ||
\begin{align} | \begin{align} | ||
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& \begin{align} | & \begin{align} | ||
= \,\, & T_i^2 T_f^2 | F(+Q_{z1}) |^2 && + T_i^2 T_f R_f F(+Q_{z1})F(-Q_{z2}) \\ | = \,\, & T_i^2 T_f^2 | F(+Q_{z1}) |^2 && + T_i^2 T_f R_f F(+Q_{z1})F(-Q_{z2}) \\ | ||
− | & && + T_i R_i T_f | + | & && + T_i R_i T_f^2 F(+Q_{z1})F(+Q_{z2}) + T_i R_i T_f R_f F(+Q_{z1}) F(-Q_{z1}) \\ |
& + T_i^2 R_f^2 | F(-Q_{z2}) |^2 && + T_i^2T_fR_f F(+Q_{z1}) F(-Q_{z2}) \\ | & + T_i^2 R_f^2 | F(-Q_{z2}) |^2 && + T_i^2T_fR_f F(+Q_{z1}) F(-Q_{z2}) \\ | ||
Line 22: | Line 55: | ||
\end{align} \\ | \end{align} \\ | ||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | ===Simplification=== | ||
+ | We can rearrange to: | ||
+ | |||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | I_d(q_{z}) = \,\, & T_i^2 T_f^2 | F(+Q_{z1}) |^2 + T_i^2 R_f^2 | F(-Q_{z2}) |^2 + R_i^2 T_f^2 | F(+Q_{z2}) |^2 + R_i^2 R_f^2 | F(-Q_{z1}) |^2 \\ | ||
+ | |||
+ | & + T_i^2 T_f R_f F(+Q_{z1})F(-Q_{z2}) \\ | ||
+ | & + T_i R_i T_f^2 F(+Q_{z1})F(+Q_{z2}) + T_i R_i T_f R_f F(+Q_{z1}) F(-Q_{z1}) \\ | ||
+ | |||
+ | & + T_i^2T_fR_f F(+Q_{z1}) F(-Q_{z2}) \\ | ||
+ | & + T_i R_i T_f R_f F(+Q_{z2})F(-Q_{z2}) + T_i R_i R_f^2 F(-Q_{z1}) F(-Q_{z2}) \\ | ||
+ | |||
+ | & + T_i R_i T_f^2 F(+Q_{z1}) F(+Q_{z2}) \\ | ||
+ | & + T_i R_i T_f R_f F(+Q_{z2})F(-Q_{z2}) + R_i^2 T_f R_f F(-Q_{z1}) F(+Q_{z2}) \\ | ||
+ | |||
+ | & + T_i R_i T_f R_f F(+Q_{z1}) F(-Q_{z1}) \\ | ||
+ | & + T_i R_i R_f^2 F(-Q_{z1})F(-Q_{z2}) + R_i^2 T_f R_f F(-Q_{z1}) F(+Q_{z2}) \\ | ||
+ | |||
+ | |||
+ | |||
+ | = \,\, & T_i^2 T_f^2 | F(+Q_{z1}) |^2 + T_i^2 R_f^2 | F(-Q_{z2}) |^2 + R_i^2 T_f^2 | F(+Q_{z2}) |^2 + R_i^2 R_f^2 | F(-Q_{z1}) |^2 \\ | ||
+ | & + 2 \times T_i^2T_fR_f F(+Q_{z1})F(-Q_{z2}) \\ | ||
+ | & + 2 \times T_iR_iT_f^2 F(+Q_{z1})F(+Q_{z2}) \\ | ||
+ | & + 2 \times T_i R_i T_f R_f [ F(+Q_{z1})F(-Q_{z1}) + F(+Q_{z2})F(-Q_{z2}) ] \\ | ||
+ | & + 2 \times T_iR_iR_f^2 F(-Q_{z1})F(-Q_{z2}) \\ | ||
+ | & + 2 \times R_i^2T_fR_fx F(-Q_{z1})F(+Q_{z2}) \\ | ||
+ | |||
+ | |||
+ | = \,\, & T_i^2 T_f^2 | F(+Q_{z1}) |^2 + T_i^2 R_f^2 | F(-Q_{z2}) |^2 + R_i^2 T_f^2 | F(+Q_{z2}) |^2 + R_i^2 R_f^2 | F(-Q_{z1}) |^2 \\ | ||
+ | & + 2 \times T_i^2T_fR_f F(+Q_{z1})F(-Q_{z2}) | ||
+ | + 2 \times T_iR_iT_f^2 F(+Q_{z1})F(+Q_{z2}) \\ | ||
+ | & + 2 \times T_i R_i T_f R_f [ F(+Q_{z1})F(-Q_{z1}) + F(+Q_{z2})F(-Q_{z2}) ] \\ | ||
+ | & + 2 \times T_iR_iR_f^2 F(-Q_{z1})F(-Q_{z2}) | ||
+ | + 2 \times R_i^2T_fR_fx F(-Q_{z1})F(+Q_{z2}) \\ | ||
+ | |||
+ | |||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | We can rewrite in a more compact form using the notation <math>T_i = T(\alpha_i)</math> and <math>F_{+1} = F(+Q_{z1})</math>: | ||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | I_d(q_{z}) | ||
+ | = \,\, & T_i^2 T_f^2 | F_{+1} |^2 + T_i^2 R_f^2 | F_{-2} |^2 + R_i^2 T_f^2 | F_{+2} |^2 + R_i^2 R_f^2 | F_{-1} |^2 \\ | ||
+ | & + 2 \times T_i^2T_fR_f F_{+1}F_{-2} | ||
+ | + 2 \times T_iR_iT_f^2 F_{+1}F_{+2} \\ | ||
+ | & + 2 \times T_i R_i T_f R_f [ F_{+1}F_{-1} + F_{+2}F_{-2} ] \\ | ||
+ | & + 2 \times T_iR_iR_f^2 F_{-1}F_{-2} | ||
+ | + 2 \times R_i^2T_fR_f F_{-1}F_{+2} | ||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | ==Expansion== | ||
+ | |||
+ | ===Terms=== | ||
+ | If one expands the <math>|...|^2</math> of the DWBA, one obtains 16 terms: | ||
+ | |||
+ | <math> | ||
+ | |||
+ | \begin{matrix} | ||
+ | & (T_i^* T_f^*) & (T_i^* R_f^*) & (R_i^* T_f^*) & (R_i^* R_f^*) \\ | ||
+ | (T_i T_f) & T_i T_i^* T_f T_f^* & T_i T_i^* T_f R_f^* & T_i R_i^* T_f T_f^* & T_i R_i^* T_f R_f^* \\ | ||
+ | (T_i R_f) & T_i T_i^* T_f^* R_f & T_i T_i^* R_f R_f^* & T_i R_i^* T_f^* R_f & T_i R_i^* R_f R_f^* \\ | ||
+ | (R_i T_f) & T_i^* R_i T_f T_f^* & T_i^* R_i T_f R_f^* & R_i R_i^* T_f T_f^* & R_i R_i^* T_f R_f^* \\ | ||
+ | (R_i R_f) & T_i^* R_i T_f^* R_f & T_i^* R_i R_f R_f^* & R_i R_i^* T_f^* R_f & R_i R_i^* R_f R_f^* \\ | ||
+ | \end{matrix} | ||
+ | |||
+ | </math> | ||
+ | |||
+ | |||
+ | <math> | ||
+ | |||
+ | \begin{matrix} | ||
+ | & (T_i^* T_f^*) & (T_i^* R_f^*) & (R_i^* T_f^*) & (R_i^* R_f^*) \\ | ||
+ | (T_i T_f) & |T_i T_f|^2 & |T_i|^2 T_f R_f^* & T_i R_i^* |T_f|^2 & T_i R_i^* T_f R_f^* \\ | ||
+ | (T_i R_f) & |T_i|^2 T_f^* R_f & |T_i R_f|^2 & T_i R_i^* T_f^* R_f & T_i R_i^* |R_f|^2 \\ | ||
+ | (R_i T_f) & T_i^* R_i |T_f|^2 & T_i^* R_i T_f R_f^* & |R_i T_f|^2 & |R_i|^2 T_f R_f^* \\ | ||
+ | (R_i R_f) & T_i^* R_i T_f^* R_f & T_i^* R_i |R_f|^2 & |R_i|^2 T_f^* R_f & | R_i R_f |^2 \\ | ||
+ | \end{matrix} | ||
+ | |||
+ | </math> | ||
+ | |||
+ | |||
+ | |||
+ | |||
+ | ===Equation=== | ||
+ | We take advantage of a more compact form using the notation <math>T_i = T(\alpha_i)</math> and <math>F_{+1} = F(+Q_{z1})</math>. The DWBA equation can thus be expanded as: | ||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | I_d(q_{z}) & = | | ||
+ | T_i T_f F_{+1} | ||
+ | + T_i R_f F_{-2} | ||
+ | + R_i T_f F_{+2} | ||
+ | + R_i R_f F_{-1} | ^{2} \\ | ||
+ | |||
+ | & \begin{align} | ||
+ | = \,\, & |T_i T_f|^2 | F_{+1} |^2 && + |T_i|^2 T_f R_f^* F_{+1}F_{-2}^* \\ | ||
+ | & && + T_i R_i^* |T_f|^2 F_{+1}F_{+2}^* + T_i R_i^* T_f R_f^* F_{+1} F_{-1}^* \\ | ||
+ | |||
+ | & + |T_i R_f|^2 | F_{-2} |^2 && + |T_i|^2T_f^*R_f F_{+1}^* F_{-2} \\ | ||
+ | & && + T_i R_i^* T_f^* R_f F_{+2}^*F_{-2} + T_i R_i^* |R_f|^2 F_{-1}^* F_{-2} \\ | ||
+ | |||
+ | & + |R_i T_f|^2 | F_{+2} |^2 && + T_i^* R_i |T_f|^2 F_{+1}^* F_{+2} \\ | ||
+ | & && + T_i^* R_i T_f R_f^* F_{+2}^*F_{-2} + |R_i|^2 T_f R_f^* F_{-1}^* F_{+2} \\ | ||
+ | |||
+ | & + |R_i R_f|^2 | F_{-1} |^2 && + T_i^* R_i T_f^* R_f F_{+1}^* F_{-1} \\ | ||
+ | & && + T_i^* R_i |R_f|^2 F_{-1}F_{-2}^* + |R_i|^2 T_f^* R_f F_{-1} F_{+2}^* \\ | ||
+ | |||
+ | \end{align} \\ | ||
+ | |||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | ===Simplification=== | ||
+ | We can rearrange to: | ||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | I_d(q_{z}) = \, \, & |T_i T_f|^2 | F_{+1} |^2 + |T_i R_f|^2 | F_{-2} |^2 + |R_i T_f|^2 | F_{+2} |^2 + |R_i R_f|^2 | F_{-1} |^2 \\ | ||
+ | |||
+ | & + |T_i|^2 T_f R_f^* F_{+1}F_{-2}^* + |T_i|^2T_f^*R_f F_{+1}^* F_{-2} \\ | ||
+ | |||
+ | & + T_i R_i^* |T_f|^2 F_{+1}F_{+2}^* + T_i^* R_i |T_f|^2 F_{+1}^* F_{+2} \\ | ||
+ | |||
+ | & + |R_i|^2 T_f R_f^* F_{-1}^* F_{+2} + |R_i|^2 T_f^* R_f F_{-1} F_{+2}^* \\ | ||
+ | |||
+ | & + T_i R_i^* |R_f|^2 F_{-1}^* F_{-2} + T_i^* R_i |R_f|^2 F_{-1}F_{-2}^*\\ | ||
+ | |||
+ | & + T_i R_i^* T_f R_f^* F_{+1} F_{-1}^* \\ | ||
+ | & + T_i R_i^* T_f^* R_f F_{+2}^*F_{-2} \\ | ||
+ | & + T_i^* R_i T_f R_f^* F_{+2}^*F_{-2} \\ | ||
+ | & + T_i^* R_i T_f^* R_f F_{+1}^* F_{-1} \\ | ||
+ | |||
+ | = \, \, & |T_i T_f|^2 | F_{+1} |^2 + |T_i R_f|^2 | F_{-2} |^2 + |R_i T_f|^2 | F_{+2} |^2 + |R_i R_f|^2 | F_{-1} |^2 \\ | ||
+ | |||
+ | & + |T_i|^2 [ T_f R_f^* F_{+1}F_{-2}^* + T_f^*R_f F_{+1}^* F_{-2} ] \\ | ||
+ | |||
+ | & + |T_f|^2 [ T_i R_i^* F_{+1}F_{+2}^* + T_i^* R_i F_{+1}^* F_{+2} ] \\ | ||
+ | |||
+ | & + |R_i|^2 [ T_f R_f^* F_{-1}^* F_{+2} + T_f^* R_f F_{-1} F_{+2}^* ] \\ | ||
+ | |||
+ | & + |R_f|^2 [ T_i R_i^* F_{-1}^* F_{-2} + T_i^* R_i F_{-1}F_{-2}^* ]\\ | ||
+ | |||
+ | & + [ T_i R_i^* T_f R_f^* F_{+1} F_{-1}^* + T_i^* R_i T_f^* R_f F_{+1}^* F_{-1} ] \\ | ||
+ | & + [ T_i R_i^* T_f^* R_f F_{+2}^*F_{-2} + T_i^* R_i T_f R_f^* F_{+2}^*F_{-2} ] \\ | ||
+ | |||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | We define <math>I_{+1}=|F_{+1}|^2</math>, and note that for any complex number <math>c</math>, it is true that <math>c+c^*=2 \mathrm{Re}[c]</math>. Thus: | ||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | I_d(q_{z}) | ||
+ | = \, \, & |T_i T_f|^2 I_{+1} + |T_i R_f|^2 I_{-2} + |R_i T_f|^2 | I_{+2} + |R_i R_f|^2 I_{-1} \\ | ||
+ | |||
+ | & + 2 |T_i|^2 \mathrm{Re}[ T_f R_f^* F_{+1}F_{-2}^* ] \\ | ||
+ | |||
+ | & + 2 |T_f|^2 \mathrm{Re}[ T_i R_i^* F_{+1}F_{+2}^* ] \\ | ||
+ | |||
+ | & + 2 |R_i|^2 \mathrm{Re}[ T_f R_f^* F_{-1}^* F_{+2} ] \\ | ||
+ | |||
+ | & + 2 |R_f|^2 \mathrm{Re}[ T_i R_i^* F_{-1}^* F_{-2} ]\\ | ||
+ | |||
+ | & + 2 \mathrm{Re}[ T_i R_i^* T_f R_f^* F_{+1} F_{-1}^* ] \\ | ||
+ | & + 2 \mathrm{Re}[ T_i R_i^* T_f^* R_f F_{+2}^*F_{-2} ] \\ | ||
+ | |||
+ | = \, \, & |T_i T_f|^2 I_{+1} + |T_i R_f|^2 I_{-2} + |R_i T_f|^2 | I_{+2} + |R_i R_f|^2 I_{-1} \\ | ||
+ | |||
+ | & + 2 |T_i|^2 \mathrm{Re}[ T_f R_f^* F_{+1}F_{-2}^* ] + 2 |T_f|^2 \mathrm{Re}[ T_i R_i^* F_{+1}F_{+2}^* ] \\ | ||
+ | |||
+ | & + 2 |R_i|^2 \mathrm{Re}[ T_f R_f^* F_{-1}^* F_{+2} ] + 2 |R_f|^2 \mathrm{Re}[ T_i R_i^* F_{-1}^* F_{-2} ]\\ | ||
+ | |||
+ | & + 2 \mathrm{Re}[ T_i R_i^* T_f R_f^* F_{+1} F_{-1}^* ] + 2 \mathrm{Re}[ T_i R_i^* T_f^* R_f F_{+2}^*F_{-2} ] \\ | ||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | ==Breaking into components== | ||
+ | The experimental data <math>I_d(q_z)</math> can be broken into contributions from the transmitted channel <math>I_{d,\mathrm{Tc}}(qz)</math> and reflected channel <math>I_{d,\mathrm{Rc}}(qz)</math>: | ||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | I_d(q_{z}) | ||
+ | & = [ | T_i T_f|^2 + |R_i R_f|^2 ] I_{R}(+Q_{z1}) + [ |T_i R_f|^2 + |R_i T_f|^2 ] I_{R}(+Q_{z2}) \\ | ||
+ | & = [ | T_i T_f|^2 + |R_i R_f|^2 ] I_{R}(q_z-\Delta q_{z,\mathrm{Tc}}) + [ |T_i R_f|^2 + |R_i T_f|^2 ] I_{R}(q_z-\Delta q_{z,\mathrm{Rc}}) \\ | ||
+ | & = [ | T_i T_f|^2 + |R_i R_f|^2 ] I_{d,\mathrm{Tc}}(q_z) + [ |T_i R_f|^2 + |R_i T_f|^2 ] I_{d,\mathrm{Rc}}(q_z) \\ | ||
+ | & = |Tc|^2 I_{d,\mathrm{Tc}}(q_z) + |Rc|^2 I_{d,\mathrm{Rc}}(q_z) \\ | ||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | We define the ratio between the channels to be: | ||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | w (q_z) | ||
+ | & = \frac{ I_{d,\mathrm{Tc}}(q_z) }{ I_{d,\mathrm{Tc}}(q_z) + I_{d,\mathrm{Rc}}(q_z) } | ||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | Such that one can compute the two components from: | ||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | I_d(q_{z}) & = |Tc|^2 ( I_{d,\mathrm{Tc}}(q_z) ) + |Rc|^2 ( I_{d,\mathrm{Rc}}(q_z) ) \\ | ||
+ | I_d(q_{z}) & = |Tc|^2 ( I_{d,\mathrm{Tc}}(q_z) ) + |Rc|^2 \left ( \frac{ I_{d,\mathrm{Tc}}(q_z) - w I_{d,\mathrm{Tc}}(q_z) }{w} \right ) \\ | ||
+ | I_d(q_{z}) & = I_{d,\mathrm{Tc}}(q_z) \times \left ( |Tc|^2 + |Rc|^2 \frac{ 1}{w} - |Rc|^2 \frac{w }{w} \right ) \\ | ||
+ | I_{d,\mathrm{Tc}}(q_z) & = \frac{ I_d(q_{z}) }{ |Tc|^2 + \frac{ |Rc|^2 }{w} - |Rc|^2 } \\ | ||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | and: | ||
+ | |||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | I_{d,\mathrm{Rc}}(q_z) & = \frac{ I_d(q_{z}) - |Tc|^2 I_{d,\mathrm{Tc}}(q_z) }{|Rc|^2} \\ | ||
+ | & = \frac{ I_d(q_{z}) }{|Rc|^2} - \frac{|Tc|^2}{|Rc|^2} I_{d,\mathrm{Tc}}(q_z) | ||
+ | \end{align} | ||
+ | </math> | ||
+ | |||
+ | or: | ||
+ | |||
+ | <math> | ||
+ | \begin{align} | ||
+ | I_d(q_{z}) & = |Tc|^2 ( I_{d,\mathrm{Tc}}(q_z) ) + |Rc|^2 ( I_{d,\mathrm{Rc}}(q_z) ) \\ | ||
+ | & = |Tc|^2 \left( \frac{w}{1-w} I_{d,\mathrm{Rc}}(q_z) \right) + |Rc|^2 ( I_{d,\mathrm{Rc}}(q_z) ) \\ | ||
+ | I_{d,\mathrm{Rc}}(q_z) & = \frac{ I_d(q_{z}) }{|Tc|^2 \frac{w}{1-w} + |Rc|^2} | ||
\end{align} | \end{align} | ||
</math> | </math> |
Latest revision as of 10:21, 5 April 2018
Contents
DWBA Equation in thin film
Using the notation Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T_i = T(\alpha_i)} for compactness, the DWBA equation inside a thin film can be written:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_d(q_{z}) & = | T_i T_f F(+Q_{z1}) + T_i R_f F(-Q_{z2}) + R_i T_f F(+Q_{z2}) + R_i R_f F(-Q_{z1}) | ^{2} \\ \end{align} }
Expansion (incorrect)
WARNING: This incorrectly ignores the complex components.
Terms
If one expands the Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle |...|^2} of the DWBA, one obtains 16 terms:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{matrix} & (T_i T_f) & (T_i R_f) & (R_i T_f) & (R_i R_f) \\ (T_i T_f) & T_i^2T_f^2 & T_i^2 T_f R_f & T_iR_iT_f^2 & T_iR_iT_fR_f \\ (T_i R_f) & T_i^2T_fR_f & T_i^2R_f^2 & T_iR_iT_fR_f & T_iR_iR_f^2 \\ (R_i T_f) & T_iR_iT_f^2 & T_iR_iT_fR_f & R_i^2T_f^2 & R_i^2T_fR_f \\ (R_i R_f) & T_iR_iT_fR_f & T_iR_iR_f^2 & R_i^2T_fR_f & R_i^2R_f^2 \\ \end{matrix} }
Equation
The equation can thus be expanded as:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_d(q_{z}) & = | T_i T_f F(+Q_{z1}) + T_i R_f F(-Q_{z2}) + R_i T_f F(+Q_{z2}) + R_i R_f F(-Q_{z1}) | ^{2} \\ & \begin{align} = \,\, & T_i^2 T_f^2 | F(+Q_{z1}) |^2 && + T_i^2 T_f R_f F(+Q_{z1})F(-Q_{z2}) \\ & && + T_i R_i T_f^2 F(+Q_{z1})F(+Q_{z2}) + T_i R_i T_f R_f F(+Q_{z1}) F(-Q_{z1}) \\ & + T_i^2 R_f^2 | F(-Q_{z2}) |^2 && + T_i^2T_fR_f F(+Q_{z1}) F(-Q_{z2}) \\ & && + T_i R_i T_f R_f F(+Q_{z2})F(-Q_{z2}) + T_i R_i R_f^2 F(-Q_{z1}) F(-Q_{z2}) \\ & + R_i^2 T_f^2 | F(+Q_{z2}) |^2 && + T_i R_i T_f^2 F(+Q_{z1}) F(+Q_{z2}) \\ & && + T_i R_i T_f R_f F(+Q_{z2})F(-Q_{z2}) + R_i^2 T_f R_f F(-Q_{z1}) F(+Q_{z2}) \\ & + R_i^2 R_f^2 | F(-Q_{z1}) |^2 && + T_i R_i T_f R_f F(+Q_{z1}) F(-Q_{z1}) \\ & && + T_i R_i R_f^2 F(-Q_{z1})F(-Q_{z2}) + R_i^2 T_f R_f F(-Q_{z1}) F(+Q_{z2}) \\ \end{align} \\ \end{align} }
Simplification
We can rearrange to:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_d(q_{z}) = \,\, & T_i^2 T_f^2 | F(+Q_{z1}) |^2 + T_i^2 R_f^2 | F(-Q_{z2}) |^2 + R_i^2 T_f^2 | F(+Q_{z2}) |^2 + R_i^2 R_f^2 | F(-Q_{z1}) |^2 \\ & + T_i^2 T_f R_f F(+Q_{z1})F(-Q_{z2}) \\ & + T_i R_i T_f^2 F(+Q_{z1})F(+Q_{z2}) + T_i R_i T_f R_f F(+Q_{z1}) F(-Q_{z1}) \\ & + T_i^2T_fR_f F(+Q_{z1}) F(-Q_{z2}) \\ & + T_i R_i T_f R_f F(+Q_{z2})F(-Q_{z2}) + T_i R_i R_f^2 F(-Q_{z1}) F(-Q_{z2}) \\ & + T_i R_i T_f^2 F(+Q_{z1}) F(+Q_{z2}) \\ & + T_i R_i T_f R_f F(+Q_{z2})F(-Q_{z2}) + R_i^2 T_f R_f F(-Q_{z1}) F(+Q_{z2}) \\ & + T_i R_i T_f R_f F(+Q_{z1}) F(-Q_{z1}) \\ & + T_i R_i R_f^2 F(-Q_{z1})F(-Q_{z2}) + R_i^2 T_f R_f F(-Q_{z1}) F(+Q_{z2}) \\ = \,\, & T_i^2 T_f^2 | F(+Q_{z1}) |^2 + T_i^2 R_f^2 | F(-Q_{z2}) |^2 + R_i^2 T_f^2 | F(+Q_{z2}) |^2 + R_i^2 R_f^2 | F(-Q_{z1}) |^2 \\ & + 2 \times T_i^2T_fR_f F(+Q_{z1})F(-Q_{z2}) \\ & + 2 \times T_iR_iT_f^2 F(+Q_{z1})F(+Q_{z2}) \\ & + 2 \times T_i R_i T_f R_f [ F(+Q_{z1})F(-Q_{z1}) + F(+Q_{z2})F(-Q_{z2}) ] \\ & + 2 \times T_iR_iR_f^2 F(-Q_{z1})F(-Q_{z2}) \\ & + 2 \times R_i^2T_fR_fx F(-Q_{z1})F(+Q_{z2}) \\ = \,\, & T_i^2 T_f^2 | F(+Q_{z1}) |^2 + T_i^2 R_f^2 | F(-Q_{z2}) |^2 + R_i^2 T_f^2 | F(+Q_{z2}) |^2 + R_i^2 R_f^2 | F(-Q_{z1}) |^2 \\ & + 2 \times T_i^2T_fR_f F(+Q_{z1})F(-Q_{z2}) + 2 \times T_iR_iT_f^2 F(+Q_{z1})F(+Q_{z2}) \\ & + 2 \times T_i R_i T_f R_f [ F(+Q_{z1})F(-Q_{z1}) + F(+Q_{z2})F(-Q_{z2}) ] \\ & + 2 \times T_iR_iR_f^2 F(-Q_{z1})F(-Q_{z2}) + 2 \times R_i^2T_fR_fx F(-Q_{z1})F(+Q_{z2}) \\ \end{align} }
We can rewrite in a more compact form using the notation Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T_i = T(\alpha_i)} and Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle F_{+1} = F(+Q_{z1})} :
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_d(q_{z}) = \,\, & T_i^2 T_f^2 | F_{+1} |^2 + T_i^2 R_f^2 | F_{-2} |^2 + R_i^2 T_f^2 | F_{+2} |^2 + R_i^2 R_f^2 | F_{-1} |^2 \\ & + 2 \times T_i^2T_fR_f F_{+1}F_{-2} + 2 \times T_iR_iT_f^2 F_{+1}F_{+2} \\ & + 2 \times T_i R_i T_f R_f [ F_{+1}F_{-1} + F_{+2}F_{-2} ] \\ & + 2 \times T_iR_iR_f^2 F_{-1}F_{-2} + 2 \times R_i^2T_fR_f F_{-1}F_{+2} \end{align} }
Expansion
Terms
If one expands the Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle |...|^2} of the DWBA, one obtains 16 terms:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{matrix} & (T_i^* T_f^*) & (T_i^* R_f^*) & (R_i^* T_f^*) & (R_i^* R_f^*) \\ (T_i T_f) & T_i T_i^* T_f T_f^* & T_i T_i^* T_f R_f^* & T_i R_i^* T_f T_f^* & T_i R_i^* T_f R_f^* \\ (T_i R_f) & T_i T_i^* T_f^* R_f & T_i T_i^* R_f R_f^* & T_i R_i^* T_f^* R_f & T_i R_i^* R_f R_f^* \\ (R_i T_f) & T_i^* R_i T_f T_f^* & T_i^* R_i T_f R_f^* & R_i R_i^* T_f T_f^* & R_i R_i^* T_f R_f^* \\ (R_i R_f) & T_i^* R_i T_f^* R_f & T_i^* R_i R_f R_f^* & R_i R_i^* T_f^* R_f & R_i R_i^* R_f R_f^* \\ \end{matrix} }
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{matrix} & (T_i^* T_f^*) & (T_i^* R_f^*) & (R_i^* T_f^*) & (R_i^* R_f^*) \\ (T_i T_f) & |T_i T_f|^2 & |T_i|^2 T_f R_f^* & T_i R_i^* |T_f|^2 & T_i R_i^* T_f R_f^* \\ (T_i R_f) & |T_i|^2 T_f^* R_f & |T_i R_f|^2 & T_i R_i^* T_f^* R_f & T_i R_i^* |R_f|^2 \\ (R_i T_f) & T_i^* R_i |T_f|^2 & T_i^* R_i T_f R_f^* & |R_i T_f|^2 & |R_i|^2 T_f R_f^* \\ (R_i R_f) & T_i^* R_i T_f^* R_f & T_i^* R_i |R_f|^2 & |R_i|^2 T_f^* R_f & | R_i R_f |^2 \\ \end{matrix} }
Equation
We take advantage of a more compact form using the notation Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T_i = T(\alpha_i)} and Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle F_{+1} = F(+Q_{z1})} . The DWBA equation can thus be expanded as:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_d(q_{z}) & = | T_i T_f F_{+1} + T_i R_f F_{-2} + R_i T_f F_{+2} + R_i R_f F_{-1} | ^{2} \\ & \begin{align} = \,\, & |T_i T_f|^2 | F_{+1} |^2 && + |T_i|^2 T_f R_f^* F_{+1}F_{-2}^* \\ & && + T_i R_i^* |T_f|^2 F_{+1}F_{+2}^* + T_i R_i^* T_f R_f^* F_{+1} F_{-1}^* \\ & + |T_i R_f|^2 | F_{-2} |^2 && + |T_i|^2T_f^*R_f F_{+1}^* F_{-2} \\ & && + T_i R_i^* T_f^* R_f F_{+2}^*F_{-2} + T_i R_i^* |R_f|^2 F_{-1}^* F_{-2} \\ & + |R_i T_f|^2 | F_{+2} |^2 && + T_i^* R_i |T_f|^2 F_{+1}^* F_{+2} \\ & && + T_i^* R_i T_f R_f^* F_{+2}^*F_{-2} + |R_i|^2 T_f R_f^* F_{-1}^* F_{+2} \\ & + |R_i R_f|^2 | F_{-1} |^2 && + T_i^* R_i T_f^* R_f F_{+1}^* F_{-1} \\ & && + T_i^* R_i |R_f|^2 F_{-1}F_{-2}^* + |R_i|^2 T_f^* R_f F_{-1} F_{+2}^* \\ \end{align} \\ \end{align} }
Simplification
We can rearrange to:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_d(q_{z}) = \, \, & |T_i T_f|^2 | F_{+1} |^2 + |T_i R_f|^2 | F_{-2} |^2 + |R_i T_f|^2 | F_{+2} |^2 + |R_i R_f|^2 | F_{-1} |^2 \\ & + |T_i|^2 T_f R_f^* F_{+1}F_{-2}^* + |T_i|^2T_f^*R_f F_{+1}^* F_{-2} \\ & + T_i R_i^* |T_f|^2 F_{+1}F_{+2}^* + T_i^* R_i |T_f|^2 F_{+1}^* F_{+2} \\ & + |R_i|^2 T_f R_f^* F_{-1}^* F_{+2} + |R_i|^2 T_f^* R_f F_{-1} F_{+2}^* \\ & + T_i R_i^* |R_f|^2 F_{-1}^* F_{-2} + T_i^* R_i |R_f|^2 F_{-1}F_{-2}^*\\ & + T_i R_i^* T_f R_f^* F_{+1} F_{-1}^* \\ & + T_i R_i^* T_f^* R_f F_{+2}^*F_{-2} \\ & + T_i^* R_i T_f R_f^* F_{+2}^*F_{-2} \\ & + T_i^* R_i T_f^* R_f F_{+1}^* F_{-1} \\ = \, \, & |T_i T_f|^2 | F_{+1} |^2 + |T_i R_f|^2 | F_{-2} |^2 + |R_i T_f|^2 | F_{+2} |^2 + |R_i R_f|^2 | F_{-1} |^2 \\ & + |T_i|^2 [ T_f R_f^* F_{+1}F_{-2}^* + T_f^*R_f F_{+1}^* F_{-2} ] \\ & + |T_f|^2 [ T_i R_i^* F_{+1}F_{+2}^* + T_i^* R_i F_{+1}^* F_{+2} ] \\ & + |R_i|^2 [ T_f R_f^* F_{-1}^* F_{+2} + T_f^* R_f F_{-1} F_{+2}^* ] \\ & + |R_f|^2 [ T_i R_i^* F_{-1}^* F_{-2} + T_i^* R_i F_{-1}F_{-2}^* ]\\ & + [ T_i R_i^* T_f R_f^* F_{+1} F_{-1}^* + T_i^* R_i T_f^* R_f F_{+1}^* F_{-1} ] \\ & + [ T_i R_i^* T_f^* R_f F_{+2}^*F_{-2} + T_i^* R_i T_f R_f^* F_{+2}^*F_{-2} ] \\ \end{align} }
We define Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle I_{+1}=|F_{+1}|^2} , and note that for any complex number Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle c} , it is true that Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle c+c^*=2 \mathrm{Re}[c]} . Thus:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_d(q_{z}) = \, \, & |T_i T_f|^2 I_{+1} + |T_i R_f|^2 I_{-2} + |R_i T_f|^2 | I_{+2} + |R_i R_f|^2 I_{-1} \\ & + 2 |T_i|^2 \mathrm{Re}[ T_f R_f^* F_{+1}F_{-2}^* ] \\ & + 2 |T_f|^2 \mathrm{Re}[ T_i R_i^* F_{+1}F_{+2}^* ] \\ & + 2 |R_i|^2 \mathrm{Re}[ T_f R_f^* F_{-1}^* F_{+2} ] \\ & + 2 |R_f|^2 \mathrm{Re}[ T_i R_i^* F_{-1}^* F_{-2} ]\\ & + 2 \mathrm{Re}[ T_i R_i^* T_f R_f^* F_{+1} F_{-1}^* ] \\ & + 2 \mathrm{Re}[ T_i R_i^* T_f^* R_f F_{+2}^*F_{-2} ] \\ = \, \, & |T_i T_f|^2 I_{+1} + |T_i R_f|^2 I_{-2} + |R_i T_f|^2 | I_{+2} + |R_i R_f|^2 I_{-1} \\ & + 2 |T_i|^2 \mathrm{Re}[ T_f R_f^* F_{+1}F_{-2}^* ] + 2 |T_f|^2 \mathrm{Re}[ T_i R_i^* F_{+1}F_{+2}^* ] \\ & + 2 |R_i|^2 \mathrm{Re}[ T_f R_f^* F_{-1}^* F_{+2} ] + 2 |R_f|^2 \mathrm{Re}[ T_i R_i^* F_{-1}^* F_{-2} ]\\ & + 2 \mathrm{Re}[ T_i R_i^* T_f R_f^* F_{+1} F_{-1}^* ] + 2 \mathrm{Re}[ T_i R_i^* T_f^* R_f F_{+2}^*F_{-2} ] \\ \end{align} }
Breaking into components
The experimental data Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle I_d(q_z)} can be broken into contributions from the transmitted channel Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle I_{d,\mathrm{Tc}}(qz)} and reflected channel Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle I_{d,\mathrm{Rc}}(qz)} :
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_d(q_{z}) & = [ | T_i T_f|^2 + |R_i R_f|^2 ] I_{R}(+Q_{z1}) + [ |T_i R_f|^2 + |R_i T_f|^2 ] I_{R}(+Q_{z2}) \\ & = [ | T_i T_f|^2 + |R_i R_f|^2 ] I_{R}(q_z-\Delta q_{z,\mathrm{Tc}}) + [ |T_i R_f|^2 + |R_i T_f|^2 ] I_{R}(q_z-\Delta q_{z,\mathrm{Rc}}) \\ & = [ | T_i T_f|^2 + |R_i R_f|^2 ] I_{d,\mathrm{Tc}}(q_z) + [ |T_i R_f|^2 + |R_i T_f|^2 ] I_{d,\mathrm{Rc}}(q_z) \\ & = |Tc|^2 I_{d,\mathrm{Tc}}(q_z) + |Rc|^2 I_{d,\mathrm{Rc}}(q_z) \\ \end{align} }
We define the ratio between the channels to be:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} w (q_z) & = \frac{ I_{d,\mathrm{Tc}}(q_z) }{ I_{d,\mathrm{Tc}}(q_z) + I_{d,\mathrm{Rc}}(q_z) } \end{align} }
Such that one can compute the two components from:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_d(q_{z}) & = |Tc|^2 ( I_{d,\mathrm{Tc}}(q_z) ) + |Rc|^2 ( I_{d,\mathrm{Rc}}(q_z) ) \\ I_d(q_{z}) & = |Tc|^2 ( I_{d,\mathrm{Tc}}(q_z) ) + |Rc|^2 \left ( \frac{ I_{d,\mathrm{Tc}}(q_z) - w I_{d,\mathrm{Tc}}(q_z) }{w} \right ) \\ I_d(q_{z}) & = I_{d,\mathrm{Tc}}(q_z) \times \left ( |Tc|^2 + |Rc|^2 \frac{ 1}{w} - |Rc|^2 \frac{w }{w} \right ) \\ I_{d,\mathrm{Tc}}(q_z) & = \frac{ I_d(q_{z}) }{ |Tc|^2 + \frac{ |Rc|^2 }{w} - |Rc|^2 } \\ \end{align} }
and:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_{d,\mathrm{Rc}}(q_z) & = \frac{ I_d(q_{z}) - |Tc|^2 I_{d,\mathrm{Tc}}(q_z) }{|Rc|^2} \\ & = \frac{ I_d(q_{z}) }{|Rc|^2} - \frac{|Tc|^2}{|Rc|^2} I_{d,\mathrm{Tc}}(q_z) \end{align} }
or:
Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle \begin{align} I_d(q_{z}) & = |Tc|^2 ( I_{d,\mathrm{Tc}}(q_z) ) + |Rc|^2 ( I_{d,\mathrm{Rc}}(q_z) ) \\ & = |Tc|^2 \left( \frac{w}{1-w} I_{d,\mathrm{Rc}}(q_z) \right) + |Rc|^2 ( I_{d,\mathrm{Rc}}(q_z) ) \\ I_{d,\mathrm{Rc}}(q_z) & = \frac{ I_d(q_{z}) }{|Tc|^2 \frac{w}{1-w} + |Rc|^2} \end{align} }