  Measurements of transverse magnetic field and velocity components from Parker
Solar Probe have revealed a coherent quasi-periodic pattern in the near-Sun
solar wind. As well as being Alfv\'enic and arc-polarised, these deflections
were characterised by a consistent orientation and an increased proton core
temperature, which was greater parallel to the magnetic field. We show that
switchbacks represent the largest deflections within this underlying structure,
which is itself consistent with the expected outflow from interchange
reconnection simulations. Additionally, the spatial scale of the deflections
was estimated to be around $1$\,Mm on the Sun, comparable to the jetting
activity observed at coronal bright points within the base of coronal plumes.
Therefore, our results could represent the in situ signature of interchange
reconnection from coronal bright points within plumes, complementing recent
numerical and observational studies. We also found a consistent relationship
between the proton core temperature and magnetic field angle across the Parker
Solar Probe encounters and discussed how such a persistent signature could be
more indicative of an in situ mechanism creating a local increase in
temperature. In future, observations of minor ions, radio bursts and remote
sensing images could help further establish the connection between reconnection
events on the Sun and signatures in the solar wind.
