Finding all possible UV resonances of effective operators is an important
task in the bottom-up approach of effective field theory. We present all the
tree-level UV resonances for the dimension-5, -6 and -7 operators in the
Standard Model effective field theory (SMEFT), and then obtain the
correspondence between the UV resonances and the effective operators from the
relations among their Wilson coefficients, through the functional matching and
operator reduction procedure. This provides a cross-dimension UV/IR dictionary
for the SMEFT at tree-level, and the methods used here, especially the on-shell
construction of general UV Lagrangian and the systematic reduction of
operators, are extendable for UV resonances of d≥8 operators in SMEFT
and other EFTs.Comment: 55 pages, 1 figure, 12 table