The 15th meeting of the MCnet network is also the kick-off meeting of the MCnetITN3 consortium, funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 722104.
Automating Basis Reduction for Effective Lagrangians in FeynRules30m
Accounting for redundancies among higher-dimensional operators is necessary in any Effective Field Theory, and has historically been a source of confusion in its applications to the Standard Model. Even while the procedure is now well-understood, reducing an arbitrary set of operators onto an agreed basis is still a time-consuming step arising in matching a given UV completion to an EFT, and at each order in perturbation theory where this plays a key role in renormalizing the theory.
Emulating the procedure used to derive the `Warsaw' basis of the dimension-six SMEFT, work to automate this reduction will be discussed using FeynRules, with the aim of providing a tool which will be useful in SMEFT calculations and lend itself to future generalization, e.g. to the construction of operator bases for theories beyond the SM, and eliminating redundancies in operators of still higher mass dimension.
Liam Ronald Moore
(University of Glasgow (GB))
We introduce a new jet substructure method based on a recursive
iteration of the Soft Drop algorithm. The recursive soft drop
algorithm introduces an additional parameter N to define the
number of layers of soft drop declustering, providing an
optimized grooming strategy for boosted objects with (N+1)-prong
decays, as well as improved stability in high pileup
conditions. We discuss the infinite N limit, where groomed jets
have a null area, and investigate their properties. We show
promising applications to jet mass resolution in boosted top and
W bosons, and demonstrate how recursive soft drop grooming can
substantially mitigate pileup effects when used in conjunction
with existing pileup-removal methods.