Authors: Tamar Ervin (UC Berkeley), Alfred Mallet (UC Berkeley), Stefan Eriksson (Laboratory for Atmospheric and Space Physics), Marc Swisdak (University of Maryland, College Park), James Juno (Princeton Plasma Physics Laboratory), Trevor A. Bowen (UC Berkeley), Orlando Romeo (UC Berkeley), Roberto Livi (UC Berkeley), Phyllis Whittlesey (UC Berkeley), Davin E. Larson (UC Berkeley), Stuart D. Bale (UC Berkeley)

Using near-Sun observations from Parker Solar Probe (PSP) Encounters 4 to 11 (Jan 2020 to March 2022), we test the suppression of magnetic reconnection onset due to flow shear. We compare estimates of the tearing mode growth rate in the presence of shear flow relative to the classic theory (Mallet et al., 2025) for time periods identified as containing reconnecting current sheets (Eriksson et al., 2024) versus non-reconnecting times, finding systematically larger growth rates for reconnecting periods. We also compare with fast, slow, and slow Alfvenic streams (Ervin et al, 2024c) and find that the growth rate is suppressed in highly Alfvenic fast and slow wind, leading to longer reconnection onset times. These wind streams have strong flow shears, supporting the idea of reconnection suppression by shear flow. This could help explain the absence of reconnection events in the highly Alfvenic, near-Sun solar wind observed by PSP.