An Observed Transition of Galaxy Spins on Void Surfaces

Abstract In linear theory, the galaxy angular momentum vectors that originate from initial tidal interactions with surrounding matter distribution intrinsically develop perpendicular alignments directions of maximum compression, regardless mass. simulations, however, spins exhibit parallel in mass range lower than a certain threshold, which depends on redshift, web type, and background cosmology. We show observed three-dimensional spiral galaxies located void surfaces Sloan Digital Sky Survey indeed transit to toward nearest centers at threshold zone, 9.51 ≤ log [ M th , ⋆ stretchy="true">/ stretchy="false">( h − 1 ⊙ stretchy="false">) stretchy="false">] 10.03 . This study presents first direct observational evidence for occurrence mass-dependent spin transition real respect non-filamentary structures cosmic web, opening way constrain conditions early universe by measuring threshold.