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The slow solar wind is typically characterized as having low Alfv\'enicity.However, Parker Solar Probe (PSP) observed predominately Alfv\'enic slow solarwind during several of its initial encounters. From its first encounterobservations, about 55.3\% of the slow solar wind inside 0.25 au is highlyAlfv\'enic ($|\sigma_C| > 0.7$) at current solar minimum, which is much higherthan the fraction of quiet-Sun-associated highly Alfv\'enic slow wind observedat solar maximum at 1 au. Intervals of slow solar wind with differentAlfv\'enicities seem to show similar plasma characteristics and temperatureanisotropy distributions. Some low Alfv\'enicity slow wind intervals even showhigh temperature anisotropies, because the slow wind may experienceperpendicular heating as fast wind does when close to the Sun. This signatureis confirmed by Wind spacecraft measurements as we track PSP observations to 1au. Further, with nearly 15 years of Wind measurements, we find that thedistributions of plasma characteristics, temperature anisotropy and heliumabundance ratio ($N_\alpha/N_p$) are similar in slow winds with differentAlfv\'enicities, but the distributions are different from those in the fastsolar wind. Highly Alfv\'enic slow solar wind contains both helium-rich($N_\alpha/N_p\sim0.045$) and helium-poor ($N_\alpha/N_p\sim0.015$)populations, implying it may originate from multiple source regions. Theseresults suggest that highly Alfv\'enic slow solar wind shares similartemperature anisotropy and helium abundance properties with regular slow solarwinds, and they thus should have multiple origins.

Alfv\'enic Slow Solar Wind Observed in the Inner Heliosphere by Parker Solar Probe