Related papers: Explaining the observed deviation in R($D^{(*)}$) …
The measured rate for D_s -> l nu decays, where l is a muon or tau, is larger than the standard model prediction, which relies on lattice QCD, at the 3.8 sigma level. We discuss how robust the theoretical prediction is, and we show that the…
Motivated by the recent CMS excess in a flavor violating Higgs decay $h \rightarrow \mu \tau$ as well as the anomaly of muon anomalous magnetic moment (muon g-2), we consider a scenario where both the excess in $h \rightarrow \mu \tau$ and…
Searches for a charged Higgs boson ($H^\pm$) decaying to a charm quark and a bottom quark ($H^\pm \to cb$) have been carried out at the Large Hadron Collider (LHC) in the decay of top quarks ($t\to H^\pm b$). In a recent search by the ATLAS…
We consider an extension of the Standard Model with an extra gauged $U(1)'$ symmetry in presence of a 2-Higgs Doublet Model structure of the scalar sector. We show that this scenario is able to explain the anomaly observed by the Atomki…
We review the parameter regions allowed by measurements of $\mathcal{R}(D^{(*)})$ and by a theoretical limit on ${\cal B}(B_{c}\to\tau\nu)$ in terms of generic scalar and pseudoscalar new physics couplings, $g_s$ and $g_p$. We then use…
The $R_{D^{(\ast)}}$ anomaly is one of the most intriguing experimental results in particle physics today. Experiments such as BaBar, Belle and LHCb have measured a consistent tension with the standard model (SM). We study several…
Within the assumption of Left-Handed (LH) New Physics (NP), we review the relations between $\mathcal{B}(B\to K^{(\ast)} \tau^+\tau^-)$ and $\mathcal{B}(B\to K^{(\ast)} \nu\bar \nu)$ for several Beyond the Standard Model (BSM) scenarios,…
The radiative leptonic $B_{c}\to\tau\bar{\nu_{\tau}}\gamma$ decay is analysed in context of 2HDM. It is shown that with large values of $tan\beta$, the contributions of Model II to the decay rate exceeds considerably the Standard Model…
The CDF collaboration recently reported a measurement of the $W$-bosos mass, $M_W$, showing a large positive deviation from the Standard Model (SM) prediction. The question arises whether extensions of the SM exist that can accommodate such…
In this thesis, we investigate the implications of the LHC Higgs data on different BSM scenarios. Since the data seem to agree with the SM expectations, any nonstandard couplings will be strongly constrained. First we investigate, in a…
We discuss the connections between the recently observed Higgs-like particle and rare B decays in the context of two Higgs doublet models (2HDMs). The measured decays of the Higgs boson to fermions and gauge bosons, along with the…
Motivated by results recently reported by the CMS Collaboration about an excess in the di-photon spectrum at about 96 GeV, especially when combined with another long-standing anomaly at the same value in the $b\bar b$ invariant mass…
Several experiments observed deviations from the Standard Model (SM) in the flavour sector: LHCb found a $4-5\,\sigma$ discrepancy compared to the SM in $b\to s\mu^+\mu^-$ transitions (recently supported by an Belle analysis) and CMS…
In light of the recent 750 GeV diphoton anomaly observed at the LHC, we study the possibility of accommodating the deviation from the standard model prediction based on the recently proposed Gauged Two Higgs Doublet Model. The model embeds…
2-Higgs Doublet Models (2HDMs) typically need to invoke an ad-hoc discrete symmetry to avoid severe flavor bounds and in addition feature massless neutrinos, thus falling short of naturally complying with existing data. However, when…
The LHC observed deviations from the Standard Model (SM) in the flavour sector: LHCb found a $4.3\,\sigma$ discrepancy compared to the SM in $b\to s\mu\mu$ transitions and CMS reported a non-zero measurement of $h\to\mu\tau$ with a…
Charged Higgs bosons are common predictions in most extensions of the Standard Model (SM) Higgs sector. Therefore, their observation would elucidate the nature of the Higgs sector. Motivated by the ATLAS collaboration's latest analysis…
We investigate an extended 3-4-1 model consisting of a new singly charged Higgs boson, implementing the minimal inverse seesaw mechanism to accommodate the large values of the $(g-2)_{e,\mu}$ anomalies as well as the lepton-flavor-violating…
Measurements of a Higgs boson at the Large Hadron Collider (LHC) have become increasingly consistent with the predictions of the Standard Model (SM). This fact puts severe constraints on many potential low-energy extensions of the Higgs…
In the search for a light Higgs boson, the ATLAS and CMS experiments have observed excesses in both the diphoton ($\gamma\gamma$) and di-tau-pair ($\tau^+\tau^-$) decay channels at about $95$ GeV. The LEP collaboration has also previously…