# 49th SLAC Summer Institute (SSI 2021)

16-27 August 2021
SLAC
America/Los_Angeles timezone

## Combined Higgs measurements in SMEFT with the ATLAS experiment

Not scheduled
20m
ZOOM videoconf (SLAC)

### Speaker

Rahul Balasubramanian (Nikhef)

### Description

Abstract:
The experimental study of the Higgs boson at the Large Hadron Collider is rapidly progressing
over the past decade. The hunt for the elusive boson is now evolving to measuring
kinematics properties of the Higgs boson interacting with other particles.

These detailed measurements provides an opportunity to study novel physical phenomena
which occur at energies which are much large than those reached by particle collisions at
the LHC. The Standard Model Effective Field Theory (SMEFT) lays the theoretical foundation
that predicts how these signatures looks like in the ATLAS detector. This sets the stage
to consistently scrutinise deviation of the data with respect to Standard Model prediction.

The latest combined Higgs measurements measure kinematic regions defined in the simplified
template cross-section framework in the decay channels of $H\rightarrow\gamma\gamma$, $H\rightarrow ZZ^*\rightarrow 4l$,
and $H\rightarrow b\bar{b}$ using the full Run-2 proton-proton collision dataset at $\sqrt{s}$ = 13 TeV
collected with the ATLAS detector in the years 2015-2018.

There are a large number of SMEFT operators that affect these measurements, however
many operators have similar effects on the measurement and the challenge is therefore
to identify the set of directions that can be constrained. In this work, we have
identified ten linear combinations of SMEFT operators that can be probed with this analysis.