Conveners
Parallel - Collider & BSM: Session 1
- Baradhwaj Coleppa
Parallel - Collider & BSM: Session 2
- Santosh K Rai
Conventional searches at the LHC operate under the assumption that Beyond the Standard Model particles undergo immediate decay upon production. However, this assumption lacks inherent a priory justification. This talk delves into the exploration of displaced decay signatures across various collider experiments. Combining insights from several studies, we show how small Yukawa couplings,...
The W boson mass and the anomalous magnetic moment of muon are two most notable anomalies that provide a stringent test of the SM and should be explained by any proposed model beyond SM. We shall address these observed discrepancies in a minimal extension of the inert two Higgs doublet model(I2HDM). Using the model parameters constrained by various theoretical considerations and...
At the Large Hadron Collider (LHC), ATLAS and CMS collaborations observed various decay modes of the light charged Higgs bosons produced by top (anti)quark decays. In this talk, I am interested in the subsequent decay of the light charged Higgs boson into a charm and a strange quark-antiquark pair and into a tau and a tau-neutrino pair, separately, in the context of the Georgi-Machacek model,...
The Inert Triplet Model (ITM) is a popular scenario with a neutral scalar Dark Matter (DM), along with an inert charged scalar in a compressed mass spectrum. The DM constraints corner the ITM to high TeV-scale mass range, the production of which is inefficient at the present and future iterations of the LHC. However, Vector Boson Fusion (VBF) at a future Muon Collider promises high production...
The Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) features a sophisticated two-level triggering system composed of the Level 1 (L1), instrumented by custom-design hardware boards, and the High-Level software based trigger (HLT). The CMS L1 Trigger receives information from calorimeters and muon detectors. Recently, a new system, called CICADA (Calorimeter Image...
In this talk, I will present a minimal model for cosmological selection of the electroweak scale that can resolve the hierarchy problem. Our model consists of a Pseudo Nambu Goldstone Boson (PNGB) and an extra Higgs doublet along with the Standard Model, with a cutoff that can be taken almost as high as the Planck scale. We consider a landscape of vacua with varying Higgs sector parameters. In...
Proton decay in six-dimensions orbifolded on T2/Z2 is highly suppressed at tree level. This is because baryon number violating operators containing only the zero mode of bulk fermions must satisfy a selection rule emerging from the remaining symmetry of the orbifold. Here we show that this relation can be evaded with operators made up of Kaluza Klein partners of the Standard Model fermions....
In the Type-I 2HDM, all the five new physical Higgs states can be fairly light, $\mathcal O$(100) GeV or less, without conflicting with current data from the direct Higgs boson searches and the B-physics measurements. In this talk, I will discuss how the new neutral and the charged Higgs bosons of the model can be simultaneously observable in the $multi-b$ final state, resulting from the...
The search for dark matter is performed in association with a Higgs boson decaying into a pair of tau leptons and significant missing transverse momentum in proton-proton collisions data of CMS detector at CERN LHC at a center-of-mass energy of 13 TeV. The results are interpreted in the framework of the 2HDM+a model and baryonic Z’ model by using data collected by the CMS experiment during Run-2.
The Yukawa coupling of the Higgs boson to the top quark is a pivotal parameter in the Standard Model, providing insights into fundamental particle interactions. This coupling is investigated through the production processes of Higgs bosons in association with top quarks, including tH and ttH. Utilizing proton-proton collision data at a centre-of-mass energy of 13 TeV, this study encompasses an...
Composite Higgs models provide a promising way to address both the hierarchy problem and the heavy top quark mass. I will discuss a class of models involving a new strongly coupled confining gauge theory, which lead to dynamical electroweak symmetry breaking by generating a composite pseudo-Nambu-Goldstone Higgs boson and a partially composite top quark. I will emphasize the pivotal role of...
The most general two-triplet extension of the Standard Model demanding custodial symmetry gives rise to the extended Georgi-Machacek (eGM) model. Via computing one-loop corrections to all $2 \rightarrow 2$ scattering amplitudes in the eGM model, we place NLO unitarity bounds on the quartic couplings. On top of that, we derive stringent conditions on the quartic couplings ensuring there exists...
The quest for new physics beyond the Standard Model (BSM) remains a cornerstone of contemporary particle physics, driving the pursuit of new particles. We present the recent results from an extensive search for BSM particle states in 'high-mass diphoton events', a signature indicative of various SM extensions such as Supersymmetry, extra dimensions, and non-minimal Higgs sectors.
Searches...
Ultraperipheral (UPC) lead-lead collisions produce very large photon fluxes, allowing for the study of fundamental quantum-mechanical processes and serving as a very good probe for physics beyond the standard model (BSM). In this talk, measurements of the light-by-light scattering (LbL, $\gamma\gamma\to\gamma\gamma$) and the Breit--Wheeler (B--W, $\gamma\gamma\to\mathrm{e}^+\mathrm{e}^-$)...
In the simplest linear seesaw picture the neutrino mass mediators can be accessible to colliders. Novel charged Higgs and heavy neutrino production mechanisms can be sizeable at $e^+ e^-$, $e^- \gamma$, $pp$, or muon colliders. The associated signatures may shed light on the Majorana nature of neutrinos and the significance of lepton number non-conservation.
To search for physics beyond the Standard Model at colliders like the Large Hadron Collider (LHC), experimentalists often rely on simple phenomenological models. So far, these searches have not yielded positive results. Nevertheless, there are compelling reasons to believe that new physics should exist at the TeV scale, within the LHC's reach. In this talk, I will demonstrate how one can...
We investigate the renormalization-group scale and scheme dependence of the $H \rightarrow gg$ decay rate at the order N$^4$LO in the renormalization-group summed perturbative theory, which employs the summation of all renormalization-group accessible logarithms including the leading and subsequent four sub-leading logarithmic contributions to the full perturbative series expansion. ...
