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The Parker Solar Probe (PSP) mission presents a unique opportunity to studythe near-Sun solar wind closer than any previous spacecraft. During its fourthand fifth solar encounters, PSP had the same orbital trajectory, meaning thatsolar wind was measured at the same latitudes and radial distances. We identifytwo streams measured at the same heliocentric distance ($\sim$0.13au) andlatitude ($\sim$-3.5$^{\circ}$) across these encounters to reduce spatialevolution effects. By comparing the plasma of each stream, we confirm that theyare not dominated by variable transient events, despite PSP's proximity to theheliospheric current sheet. Both streams are consistent with a previous slowAlfv\'enic solar wind study once radial effects are considered, and appear tooriginate at the Southern polar coronal hole boundary. We also show that theswitchback properties are not distinctly different between these two streams.Low $\alpha$-particle abundance ($\sim$ 0.6 %) is observed in the encounter 5stream, suggesting that some physical mechanism must act on coronal holeboundary wind to cause $\alpha$-particle depletion. Possible explanations forour observations are discussed, but it remains unclear whether the depletionoccurs during the release or the acceleration of the wind. Using a flux tubeargument, we note that an $\alpha$-particle abundance of $\sim$ 0.6 % in thislow velocity wind could correspond to an abundance of $\sim$ 0.9 % at 1 au.Finally, as the two streams roughly correspond to the spatial extent of aswitchback patch, we suggest that patches are distinct features of coronal holewind.

Plasma Properties, Switchback Patches and Low $\alpha$-Particle Abundance in Slow Alfv\'enic Coronal Hole Wind at 0.13 au