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In this work, we present a Mathematica package Peng4BSM@LO which calculates the contributions to the Wilson Coefficients of certain effective operators originating from the one-loop penguin Feynman diagrams. Both vector and scalar external legs are considered. The key feature of our package is the ability to find the corresponding expressions in almost any New Physics model which extends the SM and has no flavor changing neutral current (FCNC) transitions at the tree level.

The success of the first three years of operations of the CERN Large Hadron Collider (LHC) at center-of-mass energies of 7 TeV and 8 TeV radically changed the landscape of searches for new physics beyond the Standard Model (BSM) and our very way of thinking about its possible origin and its hiding place. Among the paradigms of new physics that have been probed quite extensively at the LHC, are various models that predict the existence of extra spatial dimensions. In this review, the current status of searches for extra dimensions with the Compact Muon Solenoid (CMS) detector is presented, along with prospects for future searches at the full energy of the LHC, expected to be reached in the next few years.

This article summarizes three searches for diboson resonances in the all-hadronic final state using data collected at a center-of-mass energy of $\sqrt{\mathrm{\text{s}}}$ = 13 TeV with the CMS experiment at the CERN LHC. The boson decay products are contained in one large-radius jet, resulting in dijet final states which are resolved using jet substructure techniques. The analyses presented use 2.3 fb${}^{-1}$, 35.9 fb${}^{-1}$ and 77.3 fb${}^{-1}$ of data collected between 2015 and 2017. These include the first search for diboson resonances in data collected at a 13 TeV collision energy, the introduction of a new algorithm to tag vector bosons in the context of analyzing the data collected in 2016, and the development of a novel multidimensional fit improving on the sensitivity of the previous search method with up to 30%. The results presented here are the most sensitive to date of all diboson resonance searches in the dijet final state. An emphasis on improvements in technique for vector boson tagging is made.

While the existence of a Higgs boson with a mass near 125 GeV has been clearly established, the detailed structure of the entire Higgs sector is yet unclear. Besides the Standard Model interpretation, various possibilities for extended Higgs sectors are being considered. The minimal supersymmetric extension (MSSM) features two Higgs doublets resulting in five physical Higgs bosons, which are subject to direct searches. Alternatively, more generic Two-Higgs Doublet models (2HDM) are used for the interpretation of results. The Next-to-Minimal Supersymmetric Model (NMSSM) has a more complex Higgs sector with seven physical states. Also exotic Higgs bosons decaying to invisible final states are considered. This article summarizes recent findings based on results from collider experiments.

The explanation of the small neutrino mass can be depicted using some handsome models like type-I and inverse seesaw where the Standard Model gauge singlet heavy right-handed neutrinos are deployed. The common thing in these two models is a lepton number violating parameter, however, its order of magnitude creates a striking difference between them making the nature of the right-handed heavy neutrinos a major play factor. In the type-I seesaw a large lepton number violating parameter involves the heavy right-handed neutrinos in the form of Majorana fermions while a small lepton number violating parameter being involved in the inverse seesaw demands the pseudo-Dirac nature of the heavy right-handed neutrinos. Such heavy neutrinos are accommodated in these models through the sizable mixings with the Standard Model light neutrinos. In this paper we consider the purely inverse seesaw scenario to study the pair production of the pseudo-Dirac heavy neutrinos followed by their various multilepton decay modes through the leading branching fraction at the leading order and next-to-leading order QCD at the LHC with a center-of-mass energy of 13 TeV and a luminosity of 3000 fb${}^{-1}$. We also consider a prospective 100 TeV hadron collider with luminosities of 3000 fb${}^{-1}$ and 30,000 fb${}^{-1}$, respectively to study the process. Using anomalous multilepton search performed by the CMS at the 8 TeV with 19.5 fb${}^{-1}$ luminosity we show prospective search reaches of the mixing angles for the three lepton and four lepton events at the 13 TeV LHC and 100 TeV hadron collider.

Many theories beyond the Standard Model (SM) predict new phenomena, such as $Z^{\prime }$ and vector-like quarks, in final states containing bottom- or top-quarks. It is challenging to reconstruct and identify the decay products and model the major background processes. Nevertheless, such final states offer great potential to reduce the SM backgrounds due to their characteristic decay signature. The latest searches in the third-generation quark final states using the full Run-2 proton–proton collision data collected by the ATLAS experiment are presented. Particularly, the recent results of di-bjet and top-antitop resonance searches and dark matter produced in association with a top-quark are discussed in these proceedings. The associated improvements in $b$-quark and top-quark identification techniques are also highlighted.

Quark flavor physics is the study of hadrons, their properties, and their decays into other particles. As a discipline, it simultaneously catalogues the nature of physical states within the Standard Model of particle physics, and in doing so tests the consistency and completeness of the Standard Model’s description of reality. Following the discovery of the Higgs field, it is more essential than ever to critically examine the Standard Model’s own coherence. Precision studies of quark flavor are one of the most sensitive experimental instruments for this task. I give a brief and necessarily selective overview of recent developments in quark flavor physics and discuss prospects for the next generation of experiments and facilities, with an emphasis on the energy scales of beyond Standard Model physics probed by these types of measurements.

In this paper, we explore the usage of boosted as well as semi-boosted topologies in all-hadronic $t\bar{t}$ final states in simulated $pp$ collisions at $\sqrt{s}=14$TeV, with top quarks decaying into a boosted hadronic top-jet or a W-jet and an isolated b-jet. Correlations between selected kinematic variables and their shapes are studied for scalar and vector resonances decaying to a pair of top quarks, and also for a models of $t\bar{t}$-associated production with an invisible dark matter particle pair. Stacked signal$+$background samples have been investigated in terms of the ability to resolve an excess of events over the Standard Model background in terms of the $t\bar{t}$ invariant mass, top quark transverse momentum and other 1D and 2D spectra using a parameterized detector simulation. A 2D extension of the BumpHunter algorithm is proposed, resulting in an improved signal sensitivity in specific 2D areas. We identify the most promising variables with the largest signal significance and smaller sensitivity to experimental uncertainties related to the jet energy calibration. We compare to statistical tests computing the background-only hypothesis compatibility and a likelihood fit of the signal strength.

In this paper, we explore the parameter space for processes with fermionic flavor violation within the Two Higgs Doublets Model (2HDM) type III, processes of Flavor Changing Neutral Currents (FCNCs) are present at Leading Order (LO) as dynamics beyond the Standard Model (SM) are included. We analyze the possible Yukawa couplings beyond the SM involving the quark top, as the experimental signatures would be a clear signal to conclude about the model. The processes we analyzed are same sign top pair production at the $pp$ collisions, and single top quark production in $ep$ collisions, through Deep Inelastic Scattering (DIS). To examine the scenarios that could exhibit such exotic events, we perform a scan in the parameter space to determine the observation possibilities for FCNC. We show the results considering the model parameters, coming from modified Yukawa interactions, $|{\tilde{\chi }}_{ij}^f|$ of the order one. In addition, we explore the order of magnitude of possible single top production via $\mu p$, at the proposed muon–proton collider. We found scattering values for these exotic processes of up to $\mathcal{𝒪}(10^{-2})pb$.

While the existence of a Higgs boson with a mass near 125 GeV has been clearly established, the detailed structure of the entire Higgs sector is yet unclear. Besides the Standard Model interpretation, various possibilities for extended Higgs sectors are being considered. The minimal supersymmetric extension (MSSM) features two Higgs doublets resulting in five physical Higgs bosons, which are subject to direct searches. Alternatively, more generic Two-Higgs Doublet models (2HDM) are used for the interpretation of results. The Next-to-Minimal Supersymmetric Model (NMSSM) has a more complex Higgs sector with seven physical states. Also exotic Higgs bosons decaying to invisible final states are considered. This article summarizes recent findings based on results from collider experiments.

The ATLAS experiment at the Large Hadron Collider performed searches for heavy Higgs bosons, whose presence would establish the existance of new physics. Searches for charged and neutral Higgs bosons are carried out using 8 or 13 TeV data for various production modes and in many different final states. No deviations from Standard Model expectations are observed. Exclusions limits are set on the production cross section and on parameters in various benchmark models.

A search for excited neutrinos, the analysis of multi-lepton final states, a search for doubly charged Higgs production and a general search for high-P_T phenomena at HERA are reported. The searches use data samples of e^±p collisions with a centre-of-mass energy collected by the H1 and ZEUS experiments at HERA in the years 1994-2005 with integrated luminosities up to . Overall no significant deviations of the experimental observations from the Standard Model (SM) expectation are found.

We review the use of invariant mass distributions in cascade decays to measure the masses of New Physics (NP) particles in scenarios where the final NP cascade particle is invisible. We extend earlier work by exploring further the problem of multiple solutions for the masses.

Dimension-six operators allow to parametrize model-independently the leading deviations from the SM due to heavy new physics. We separate these BSM contributions into different groups constrained at different levels of precision, and provide bounds on their Wilson coefficients through a global fit that takes into account the most relevant experiments. This allows us to identify which directions can be considered closed and which, instead, can still potentially hide sizable BSM effects. In particular, the individual BRs of the Higgs scalar into fermions, γγ and Z_γ and the production modes GG → h, VV → h are unconstrained by other experiments, while the deviations in the differential distributions of can be related to modifications of triple gauge couplings.

These proceedings present a number of searches for supersymmetric particles as well as particles from exotic models. The searches are conducted with the ATLAS experiment at the LHC analysing data taken in 2011 and 2012. Various final states with different numbers of leptons, jets and a varying amount of missing transverse momentum are investigated. Inclusive as well as exclusive searches are performed. Since no new deviations from the Standard Model have been observed, lower limits on the masses of the particles in question are derived. Depending on the particular models, mass limits exist from about 0.1 TeV up to 10 TeV.