  We report the first measurement of the $^{10}{\rm B}(\alpha,n)^{13}{\rm N}$
reaction in a polar-direct-drive exploding pusher (PDXP) at the National
Ignition Facility (NIF). This work is motivated by the need to develop
alternative mix diagnostics, radiochemistry being the focus here. The target is
composed of a $65/35\,\rm at.\,\%$ deuterium-tritium (DT) fill surrounded by a
roughly $30\,\mu\rm m$ thick beryllium ablator. The inner portion of the
beryllium ablator is doped with $10\,\rm at.\,\%$ of $^{10}{\rm B}$.
Radiation-hydrodynamics calculations were performed in 1D to optimize both the
remaining boron rho-R and the DT neutron yield. A charged-particle transport
post-processor has been developed to study $\alpha$-induced reactions on the
ablator material. Results indicate a large $^{13}{\rm N}$ production from
$\alpha$-induced reactions on $^{10}{\rm B}$, measurable by the radiochemical
analysis of gaseous samples system at the NIF. The PDXP target N201115-001 was
successfully fielded on the NIF, and nitrogen from the $^{10}{\rm
B}(\alpha,n)^{13}{\rm N}$ reaction was measured. The $^{13}{\rm N}$ production
yield, as well as the DT neutron yield, was, however, lower than expected. Some
of the reduced yields can be explained by the oblate shape, but the ratios of
the various radiochemical signals are not commensurate with expectations based
on a simple reduction of the 1D results. Preliminary 2D radiation-hydrodynamics
computations are consistent with the experimental measurements, and work is
ongoing to extend the radiochemistry analysis into higher dimensions.
