# Muon Decay Asymmetry

Angular distribution of the *e*^{+}
from *µ*^{+} decay: the
*asymmetry* (anisotropy) of the distribution is 100%
for the highest *e*^{+} energy (52.83 MeV)
and zero (*i.e.*, an isotropic distribution)
for half as big an *e*^{+} energy.
For zero *e*^{+} energy (not shown)
the asymmetry is *negative*.

Solid lines: energy spectrum *E(x)*/2 (*e*^{+}
energy = *x* times 52.83 MeV)
from normal *µ*^{+} decay
and *x*-dependence of *µ*^{+} decay asymmetry
*a(x)* [degree of correlation between *e*^{+} momentum
and *µ*^{+} spin direction].
Dashed line: weighted *µ*^{+} decay
asymmetry spectrum, the product of *E(x)/2* and *a(x)*.

Jess H. Brewer
Last modified: Fri Nov 28 17:53:24 EST