This talk presents recent precision measurements of key properties of the Higgs boson using the full dataset of proton-proton collisions at √s = 13 TeV collected during Run 2 of the LHC by the ATLAS experiment. The Higgs boson mass is determined with high accuracy through its decays into two photons and four leptons, and the adopted analysis strategies and experimental techniques will be...
We investigate an extension of the Standard Model featuring a local $U(1)_X$ gauge symmetry, an additional complex scalar singlet, and two scalar doublets, one of which is inert. The scalar sector consists of an active doublet responsible for electroweak symmetry breaking, an inert doublet that yields a scalar Dark Matter candidate, and a singlet scalar whose vacuum expectation value...
An important aspect of the Higgs boson is its width–the quantity related to its lifetime and energy spectrum. Methods for measuring the Higgs boson total decay width from the off-shell to on-shell signal strength ratio will be presented for the decays of H→WW→2l2ν, H→ZZ→2l2ν, and H→ZZ→4l.
Measurement of the Higgs boson width from the on-shell peak using the H->γγ final state will be presented...
The discovery of the Higgs boson with the mass of about 125 GeV completed the particle content predicted by the Standard Model. Even though this model is well established and consistent with many measurements, it is not capable of explaining some observations by itself. Many extensions of the Standard Model addressing such shortcomings introduce beyond-the-Standard-Model couplings to the Higgs...
The measurement of the Higgs boson width is a critical test of the Standard Model, with significant implications for understanding electroweak symmetry breaking. Direct measurements are limited by detector resolution, but it can be measured with greater precision through a combined analysis of on-shell and off-shell Higgs boson production. While results for on-shell production have been...
The tantalising prospect that hints of scalars lighter than the 125 GeV Higgs boson may have already shown themselves at the LEP and LHC or will, at least, emerge during the run of the upcoming generation of colliders, has brought a renewed interest into scalar sectors with fields beyond the Standard Model. The addition of a second Higgs doublet stands as one of the simplest possible...
Decays of the Higgs boson into pairs of bosons offer some of the most precise avenues for measuring its production cross sections and probing its fundamental properties. This talk presents the latest cross section measurements by the ATLAS experiment in bosonic decay channels, based on proton-proton collision data collected at sqrt(s) =13 TeV during Run 2 of the LHC, with the inclusion of...
The Standard Model predicts the Higgs boson to be a CP-even scalar, but CP-odd contributions to its interactions with vector bosons and quarks are not yet strongly constrained. Various Higgs boson production and decay processes provide valuable tools to investigate the CP nature of these interactions. This talk presents the most recent measurements of the CP properties of Higgs boson...
Kinematic effects in the Higgs boson decay to four leptons are investigated using full detector simulation combined with matrix element techniques. The analysis is optimized to enhance sensitivity to the tensor structure of Higgs boson interactions and the spin correlations present in the decay process. The study is based on data collected by the CMS experiment at the LHC. The interactions of...
The extensive and ambitious physics program planned for the Future Circular Collider for electrons and positrons (FCC-ee) demands exceptional detector performance. This talk systematically investigates how different detector configurations impact jet flavor identification and their effects on high-profile physics analyses. Using Higgs boson coupling measurements and searches for invisible...
Higgs boson pair production (HH) plays a central role in probing the Higgs boson self-interactions, which are key to understanding the shape of the Higgs potential and the mechanism of electroweak symmetry breaking. This talk presents the latest results from the ATLAS experiment on non-resonant Higgs boson pair production, based on the full Run 2 dataset collected at\sqrt{s} = 13 TeV, with the...
The High-Luminosity LHC (HL-LHC) is expected to deliver an integrated dataset of approximately 3 ab⁻¹, enabling detailed studies of Higgs boson processes with unprecedented precision. Projections based on current analyses have been performed to estimate the expected measurement accuracy and identify potential limitations. The large data sample will also significantly enhance sensitivity to...
A basic research goal of high energy physicists is to shed light on the reality of the Higgs mechanism through the study of the Higgs potential. Indeed an important test of the Standard Model is a determination of the form of the Higgs potential and the Higgs field self-coupling. The trilinear self-coupling can be extracted from the measurement of non-resonant Higgs boson pair (HH) production....
The title says it all
Precise predictions for double Higgs production are essential to probe the Higgs self-coupling at future colliders. A major source of theoretical uncertainty arises from the choice of the top-quark mass renormalization scheme, which strongly affects the predicted cross sections at high energy. In my talk, I will discuss the origin of these uncertainties and show that the mass effects follow a...
The most recent results from the CMS collaboration on measurements of non-resonant HH production using bbγγ final states and their combination using the data set collected by the CMS experiment at a centre of mass energy of 13.6 TeV will be presented
Precise predictions for Higgs decays are crucial for new physics searches. Possible deviations from the Standard Model (SM) can be investigated in a model-independent way by using the Standard Model Effective Field Theory (SMEFT). We present the complete set of predictions for the 2- and 3- body Higgs decays at next-to-leading order (NLO), considering QCD and electroweak corrections and...
The FCC-ee offers powerful opportunities to determine the Higgs boson parameters, exploiting about 2*10^6 e+e-→ZH events and almost 10^5 WW→H events at centre-of-mass energies around 240 and 365 GeV. The determination of the Higgs boson mass with a precision significantly better than the Higgs boson width (4.1 MeV in the Standard Model) is a prerequisite to either constrain or measure the...
A direct probe of the Higgs boson trilinear self-coupling is possible via Higgs boson pair production, making di-Higgs analyses particularly interesting. In addition, HH production via vector boson fusion, the second-leading HH production process, has a unique sensitivity to the interaction between two Higgs bosons and two vector bosons. Furthermore, enhancements to the di-Higgs production...
We present improved measurement of HH→4b production cross section from Run 3 CMS data collected in 2022 and 2023, covering both resolved and merged topologies. We highlight the recent advancements and novel techniques to significantly enhance the analysis sensitivity.
The Higgs boson provides a unique window into new physics, and a high-energy muon collider offers an unparalleled environment to explore this potential. In this talk, I will discuss how a dedicated forward muon detector can be leveraged to probe BSM physics in the Higgs sector. Detecting forward muons allows us to efficiently search for invisible Higgs decays and heavy states that couple to...
The Higgs mechanism is a cornerstone of the Standard Model, and its self-coupling is a key parameter for experimental verification. Double-Higgs production provides tree-level sensitivity to the trilinear self-coupling and becomes measurable at sufficiently high center-of-mass energies. At 550 GeV in electron–positron collisions, the dominant channel is di-Higgs strahlung, with a smaller...
A direct probe of the Higgs boson trilinear self-coupling is possible via Higgs boson pair production, making di-Higgs analyses particularly interesting. In addition, HH production via vector boson fusion, the second-leading HH production process, has a unique sensitivity to the interaction between two Higgs bosons and two vector bosons. Furthermore, enhancements to the di-Higgs production...
Effective Field Theories and anomalous couplings including CP violation provide interesting ways to parameterize indirect BSM physics, when its characteristic scale is larger than the one directly accessible at the LHC, for a large class of models. Constraints on such effects derived by measurements of several production and decay modes of the Higgs boson and their combination on the data set...
In this talk I will discuss differential theoretical predictions for Higgs-boson production in weak-boson fusion and its subsequent decay $H\to b\bar{b}$.
The distinct kinematics of weak-boson fusion allow us to suppress QCD backgrounds by imposing appropriate event selection criteria. However, it was recently observed that in fixed-order calculations these strict event selection criteria...
The study of Higgs boson production in association with one or two top quarks offers a unique opportunity to probe the interactions between the two heaviest particles in the Standard Model. This talk presents measurements of key Higgs boson properties—specifically the production cross section and CP nature—in events produced via tH and t\bar{t}H processes. The results are based on the full Run...
Geometric methods have emerged in recent years, which allow for the expression of theories in a manifestly covariant form under field redefinitions through relating physical quantities to geometric structures.
Using jet bundles it is possible to express higher derivative terms in a geometric fashion, relating their couplings to the geometry of the bundle itself.
In this talk a brief...
The largest source of uncertainty for the gluon-gluon fusion HIggs boson cross section comes for the combination of PDF and $\alpha_s $ uncertainties. These uncertainties
also play a role in other Higgs boson subprocesses. This talk will focus on the current status of PDF uncertainties relevant for Higgs production and prospects for future improvements.
In addition, a preview of the 2025...
Detailed measurements of Higgs boson decays into leptons provide a direct probe of the Yukawa interactions and the mechanism of fermion mass generation in the Standard Model. This talk presents the latest results from the ATLAS experiment on Higgs boson decays into pairs of tau leptons, using the full Run 2 dataset of proton-proton collisions at $\sqrt{s}$=13 TeV, with the inclusion of...
Multi-Higgs boson production processes can provide essential insights into the scalar sector of the Standard Model (SM). Exploring the production of three Higgs bosons is primarily motivated by the unique opportunity it offers to measure the Higgs quartic self-coupling. Although observing triple Higgs production within the SM presents significant experimental challenges at the LHC, due to its...
We will discuss the latest STXS and differential measurements of Higgs boson cross sections with the CMS detector in bosonic and fermionic decay channels and their combination. The data collected during Run 3 of the LHC by the CMS experiment are used. EFT interpretation will be added.
Precision measurements of Higgs boson couplings and kinematic properties can be performed using the data collected by the ATLAS experiment, leveraging a variety of final states and production modes to probe different regions of phase space with increasing accuracy. By combining these measurements, the strengths of individual channels are maximally exploited, providing the most stringent global...
In the Standard Model, the ground state of the Higgs field is not found at zero but instead corresponds to one of the degenerate solutions minimising the Higgs potential. In turn, this spontaneous electroweak symmetry breaking provides a mechanism for the mass generation of nearly all fundamental particles. Experimentally, the Higgs boson trilinear and quadratic couplings and thereby the shape...
The title says it all
We present searches for rare decays and beyond standard model of the Higgs boson with the CMS detector.
Probing the Yukawa couplings between the Higgs boson and fermions is essential to understanding the origin of fermion masses. Higgs boson decays into pairs of quarks offer a direct window into these couplings and broader Higgs boson properties. This talk presents ATLAS measurements of Higgs decays into bottom quark pairs and searches for decays into charm quark pairs, based on the full Run 2...
The High-Luminosity LHC (HL-LHC) is expected to deliver an integrated dataset of approximately 3 ab⁻¹, enabling detailed studies of Higgs boson processes with unprecedented precision. Projections based on current analyses have been performed to estimate the expected measurement accuracy and identify potential limitations. This talk will present the ATLAS experiment’s prospects for Higgs...
With the full run-2 data and with the advent of ML flavour tagging techniques, a lot of progress has been made to constrain the couplings of the Higgs to c-quarks and b-quarks. In this talk, we present the latest results of direct Higgs to heavy flavour couplings by the CMS experiment in the ttH/cH production, as well as the results obtained in indirect ways.
Higgs boson production through gluon fusion in association with two jets is an irreducible background to Higgs boson production through vector boson fusion. Despite a range of available simulation tools, precise predictions for the corresponding final state are hard to achieve. Using state-of-the art fixed-order calculations as the baseline for a comparison, we perform a detailed study of...
This talk presents a search for the production of a Higgs Boson in association with two vector bosons (VVH) via vector boson scattering (VBS). The VBS production of VVH is sensitive to both the Higgs boson trilinear self-coupling (HHH) and the quartic coupling between vector bosons and the Higgs boson (VVHH), potentially providing complementary constraints to those obtained from the di-Higgs...
Though the Standard Model (SM) of particle physics has been a very successful theory in explaining a wide range of measurements, there are still many questions left unanswered such as incorporation of gravity into SM, neutrino masses, matter-antimatter asymmetry, supersymmetry, or existence of dark matter candidates. One of the possible solutions to address these challenges is the extension of...
Understanding the particle nature of dark matter remains one of the key challenges in contemporary physics. Although the thermal relic picture provides a natural explanation for the observed dark matter density, the continuing absence of positive signals in direct detection experiments calls into question the simplest WIMP hypotheses. A compelling alternative scenario emerges when dark matter...
The discovery of the Higgs boson with the mass of about 125 GeV completed the particle content predicted by the Standard Model. Even though this model is well established and consistent with many measurements, it is not capable to solely explain some observations. Many extensions of the Standard Model addressing such shortcomings introduce additional neutral Higgs-like bosons or additional...
We present the searches for additional resonances in Higgs sector with the CMS detector. The presented results include searches in the low and high mass regions.
Searches for resonant Higgs bosons decaying into two scalar bosons have been attracting increasing attention at the Large Hadron Collider (LHC). The CMS Collaboration has studied various X→YH final states, and many beyond-the-Standard-Model (BSM) theories predict new scalar particles produced in association with the Standard Model Higgs boson. To further explore this sector, we present...
The search for new particles, conducted at the LHC by the ATLAS and CMS collaborations, covers several production and decay modes, leading to a large variety of final states that could be observed in both detectors. This review focuses on the production of new heavy scalars that have a Higgs boson in the final state. In particular, the three cases: resonant production of a heavy scalar X...
The FCC-ee programme is uniquely positioned to provide unprecedented precision on the fundamental properties of the Higgs boson. At the center-of-mass energies 240 and 365 GeV, the FCC-ee will produce millions of Higgs bosons via Higgs-strahlung and vector boson fusion. The clean experimental environment allows a model-independent measurement of the absolute ZH cross-section to better than...
Effective Field Theories and anomalous couplings including CP violation provide interesting ways to parameterize indirect BSM physics, when its characteristic scale is larger than the one directly accessible at the LHC, for a large class of models. Constraints on such effects derived by measurements of several production and decay modes of the Higgs boson and their combination on the data set...
The FCC-hh, operating at a centre-of-mass energy of 84 TeV, will produce unprecedentedly large samples of single and double Higgs bosons, enabling detailed studies of rare decays and precise measurements of the Higgs self-coupling. With billions of single-Higgs events, FCC-hh will measure rare decays such as H→μμ, H→γγ, and H→Zγ with percent-level precision. It will also significantly enhance...
Measurements of the Higgs boson’s decays to heavy quarks—especially the dominant H→bb̄ mode and the much rarer H→cc̄—pose formidable challenges at the LHC. In H→bb̄ searches, overwhelming hadronic backgrounds dilute the signal, while the small H→cc̄ branching fraction and the difficulty of distinguishing c‑jets from both b‑ and light‑flavour jets further complicate the measurement. Limited...
Supersymmetry (SUSY) provides elegant solutions to several problems in the Standard Model, and searches for SUSY particles are an important component of the LHC physics program. This talk will present the latest results from SUSY searches from ATLAS. A variety of models and possible final states are considered, both in R-parity-conserving and R-parity-violating scenarios. Results going beyond...
