Abstract
Abstract
We test clipping effective field theory (EFT) simulations as a method of ensuring EFT validity. The procedure imposes that, at the level of the simulation, the invariant mass of a
$$W^+W^-$$
W
+
W
-
pair
$$M_{WW}$$
M
WW
is less than the new physics scale
$$\Lambda $$
Λ
. We compare this to two other methods, comparison bin by bin of dimension-6 and dimension-8 squared contributions and implementing a cut on data. We find that setting
$$M_{WW}
M
WW
Λ
is not strict enough to ensure that the hierarchy of EFT operators is respected for dimension-6 and dimension-8 contributions. We also show that, even when using a stricter cut on
$$M_{WW}$$
M
WW
, due to different correlations between
$$M_{WW}$$
M
WW
and
$$M_{e\mu }$$
M
e
μ
at different EFT orders, the bins in
$$M_{e\mu }$$
M
e
μ
(the invariant mass of the leptons originating from
W
decays) used in an EFT fit may not truly be in the regime of EFT validity when performing a dimension-6 fit with
$$M_{WW}
M
WW
Λ
. We also explore the correlations of three transverse mass observables:
$$M_{T1}, M_{T2}$$
M
T
1
,
M
T
2
and
$$M_{T3}$$
M
T
3
, finding that
$$M_{T1}$$
M
T
1
and
$$M_{T3}$$
M
T
3
follow the
$$M_{WW}$$
M
WW
distribution more closely than
$$M_{e\mu }$$
M
e
μ
. We present sensitivity studies using both the
$$M_{T3}$$
M
T
3
distribution and
$$M_{e\mu }$$
M
e
μ
distribution. We test implementing an experimental cut on
$$M_{T3}$$
M
T
3
in place of clipping the EFT simulation at
$$M_{WW}
M
WW
Λ
. We finally comment that adding
$$M_{WW}
M
WW
Λ
cuts only to the EFT simulation could be interpreted as modifying the SMEFT expansion by a form factor and could therefore impact the model independence of EFT fits under this procedure.