Updates in arXiv:2502.20976 with respect to LHCHWG-2022-004:
1. This note: The reweighting now includes 3 variables: mhh, |cos(theta*)|, and ptHH.
LHCHWG-2022-004: Used only one variable (mhh).
2. This note: The reweighting is derived for both SMEFT and HEFT at 13 and 13.6 TeV.
LHCHWG-2022-004: Only covered HEFT at 13 TeV.
3. This note: We recommend using one or more EFT samples as reference samples for applying the reweighting.
LHCHWG-2022-004: Used an SM reference sample.
4. This note: We introduce a new method to combine reference samples via a convex combination based on a distance measure that depends on the Wilson coefficients. Essentially, this means adding two reference samples together where each sample gets a weight which vary depending on the Wilson coefficients. A weighted sum essentially.
LHCHWG-2022-004: Did not use such a method.
5. This note: We show that mhh-based reweighting struggles to capture ptH, especially in cases of destructive interference between the EFT and SM contributions, while it works well in cases of constructive interference.
LHCHWG-2022-004: Only noted that ptH is sometimes not well captured by mhh-based reweighting.
