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Another unpolarized nucleus

Assuming a target consisting of 2 types of nuclei: nD polarized deuteron nuclei with cross section \( \sigma _{D} \) and nN unpolarized nuclei with cross section \( \sigma _{N} \). Using eq. 5 for summation and normalization leads to:


\begin{displaymath}N^{hP}\propto n_{D}\sigma _{D}(h,P,T)+n_{N}\sigma _{N}(h)\end{displaymath}

Beam-target asymmetry (eq. 2) with average polarizations according to equations 6-10:

\begin{displaymath}A_{BT}=\frac{n_{D}\sigma ^{(D)}_{0}\left[ \left\langle hP\rig...
...angle A_{d}^{V}+\left\langle T\right\rangle A_{ed}^{T}\right] }\end{displaymath}

Assuming that \( \left\langle h\right\rangle A_{e}^{(N)}=0 \)the asymmetry can be expressed in another form:

 \begin{displaymath}
A_{BT}=f\frac{\left\langle hP\right\rangle A_{ed}^{V}+\left\...
...right\rangle A_{d}^{V}+\left\langle T\right\rangle A_{ed}^{T}}
\end{displaymath} (11)

with the dilution factor f

 \begin{displaymath}
f=\frac{n_{D}\sigma _{0}^{(D)}}{\frac{n_{N}\sigma _{0}^{(N)}...
...\left\langle T\right\rangle A_{d}^{T}}+n_{D}\sigma _{0}^{(D)}}
\end{displaymath} (12)

The concept of dilution factor according to equations 11 and 12 is only applicable if the terms of the ``diluting'' nucleus are limited to the denominator, otherwise the factorization does not work.



Marko Zeier
2001-02-17