* QUESTIONS: UNCERTAINTIES
** Can we neglect theory uncertainties on measurements (e.g. uncertainty on m_Z, G_F) used to constrain EFT parameters? Or should we propagate them, and how? [Michael D.]
** What uncertainty associated to choice of truncation in code implementation (e.g. calculation of UFO file)? [Michael D.]
- Codes use Lagrangian expressed with same base (Warsaw) up to truncation assumption, and same inputs and corrections, so they are expected to give the same results (and difference only numerical, cannot be used to estimate uncertainty)
- Series expanded up to Lambda^-2, uncertainties up to \Lambda^-4. In order to quantify uncertainties, one would need to to do dimension 8, and compare different bases
- Note that there might be numerical uncertainties at higher orders when using a different base before truncation
- One can estimate uncertainties including (some of the) \Lambda-4 term or not [Giovanni P.]; note that this is not guarantee to cover for all uncertainty since we do not know the value of the coefficients in front of the terms we are adding or removing.
- Full dim-8 calculation for H->yy available soon [Mike T.]
* QUESTIONS: HIGGS
** SMEFTsim vs SMEFT@NLO
- Check results at LO from both codes, they should agree even if different mapping/implementation in codes [Gauthier]
- Concerns about \alpha_s: \alpha_s extracted from complicated fit, impact of use on EFT fit interpretation unclear. Recommended approach: clearly state what \alpha_s value used for interpretation.
** NLO QED MC tool for H->yy
- Insertion of operators in loop: analytic calculation exists, but no tool for MC generation.
- For H->yy, analysis calculation can be used; for other channel (e.g. H->WW) where it would introduce dependence in acceptance, MC generation is needed.
* REQUESTS
** Mapping of operators between tools?
- Rosetta cold do it [Fabio M.]
** Documentation for complicated process generation
- Tool authors please provide mode documentation of correct settings to be used, and a possible bugs...
* MORE DISCUSSION
** Is there value in providing results both with linear term (\Lambda^-2) only, and with quadratic term included (dim-6 of \Lambda^-4 terms)?
- Yes, comparison allows to assess convergence of EFT expansion
- If one computes parameterisation up to \Lambda^-4 terms, it is then trivial to have both results (even if higher order will be computationally more expensive)
* 2 single insertions vs 1 double insertion
- 2 single insertions -> normal
- 1 double insertion implies interference with SM to be computed
- There are reasons to consider this a pure dime-8 problem (dim-8 in amplitude)
* THEORY SUMMARY
- m_W = pole mass, easier to control
- Other correction due to SMEFT easier to determine via \alpha(m_Z)
- Normalization scheme in SMEFTsim is only choice of input since it's LO
- Request to experimentalists: prepare wish-list w/ priorities