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-rw-r--r--content/know/concept/coulomb-logarithm/index.pdc9
1 files changed, 6 insertions, 3 deletions
diff --git a/content/know/concept/coulomb-logarithm/index.pdc b/content/know/concept/coulomb-logarithm/index.pdc
index 649806b..71b13a8 100644
--- a/content/know/concept/coulomb-logarithm/index.pdc
+++ b/content/know/concept/coulomb-logarithm/index.pdc
@@ -143,8 +143,8 @@ We know that the deflection grows for smaller $b$,
so it would be reasonable to choose $b_\mathrm{large}$ as the lower limit.
For very large $b$, the plasma shields the particles from each other,
thereby nullifying the deflection,
-so as upper limit
-we choose the Debye length $\lambda_D$,
+so as upper limit we choose
+the [Debye length](/know/concept/debye-length/) $\lambda_D$,
i.e. the plasma's self-shielding length.
We thus find:
@@ -157,12 +157,15 @@ $$\begin{aligned}
\end{aligned}$$
Here, $\ln\!(\Lambda)$ is known as the **Coulomb logarithm**,
-with $\Lambda$ defined as follows:
+with the **plasma parameter** $\Lambda$ defined below,
+equal to $9/2$ times the number of particles
+in a sphere with radius $\lambda_D$:
$$\begin{aligned}
\boxed{
\Lambda
\equiv \frac{\lambda_D}{b_\mathrm{large}}
+ = 6 \pi n \lambda_D^3
}
\end{aligned}$$