Measurement of the hyperfine coupling constants and absolute energies of the $8p{}^2{P}_{1\mathrm{/}2}$ and $8p{}^2{P}_{3\mathrm{/}2}$ levels in atomic cesium

We report measurements of the hyperfine coupling constant for the $8p{}^2{P}_{1\mathrm{/}2}$ level of atomic cesium, ${}^{133}$Cs, with a relative uncertainty of $\sim$0.019%. Our result is $A=42.933(8)$ MHz, in good agreement with recent theoretical results. We also examine the hyperfine structure of the $8p{}^2{P}_{3\mathrm{/}2}$ state, and derive new values for the state energies of the $8p{}^2{P}_{1\mathrm{/}2}$ and $8p{}^2{P}_{3\mathrm{/}2}$ states of cesium.