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Recently a cosmic ray propagation model has been introduced, whereanisotropic diffusion is used as a mechanism to allow for $\mathcal{O}(100)$km/s galactic winds. This model predicts a reduced antiproton background flux,suggesting an excess is being observed. We implement this model in GALPROPv50.1 and perform a $\chi^2$ analysis for B/C, $^{10}$Be/$^{9}$Be, and therecent PAMELA $\bar{p}/p$ datasets. By introducing a power-index parameter$\alpha$ that dictates the dependence of the diffusion coefficient $D_{xx}$ onheight $|z|$ away from the galactic plane, we confirm that isotropic diffusionmodels with $\alpha=0$ cannot accommodate high velocity convective windssuggested by ROSAT, while models with $\alpha=1$ ($D_{xx}\propto |z|$) can givea very good fit. A fit to B/C and $^{10}$Be/$^{9}$Be data predicts a lower$\bar{p}/p$ flux ratio than the PAMELA measurement at energies betweenapproximately 2 GeV to 20 GeV. A combined fit including in addition the$\bar{p}/p$ data is marginal, suggesting only a partial contribution to themeasured antiproton flux.

Antiproton Flux in Cosmic Ray Propagation Models with Anisotropic Diffusion