arXiv subjects

Huseyin Dag

Publications and source records attributed to Huseyin Dag.

3 recordsLinked to original sources

arXiv2025

Resolving the W-Boson Mass in the Lepton Specific Two Higgs Doublet Model

In 2022, the CDF Collaboration reported the $W$-boson mass, $M_W=80.4335\pm0.0094~\mathrm{GeV}$, which deviates from the Standard Model (SM) prediction, $M_W^{\rm SM}=80.357\pm0.006~\mathrm{GeV}$, by about $7σ$. By contrast, the CMS Collaboration obtained $M_W=80.3602\pm0.0099~\mathrm{GeV}$, very close to the SM global electroweak fit value of $\sim80.357~\mathrm{GeV}$. Motivated by this situation, we reassess the $W$-boson mass within the Lepton-Specific Two Higgs Doublet Model (LS-2HDM). We perform random scans (generated with SARAH 4.13.0 and evaluated with SPheno 4.0.3) and confront the results with up-to-date theoretical and experimental constraints. In the LS-2HDM, if $h_1$ is the SM-like Higgs at $m_{h_1}\simeq125$ GeV with $|\cos(β-α)|\lesssim0.06$, $17\lesssim\tanβ\lesssim39$, $144\lesssim m_{h_2}\lesssim414$ GeV, and $435\lesssim m_{A,H^{\pm}}\lesssim685$ GeV, the model reproduces the 2024 CMS $W$-boson mass within $3σ$. Solutions near the 2022 CDF value, $M_W=80.4335\pm0.0094~\mathrm{GeV}$, survive; however, after applying all constraints, including HiggsTools, they approach it at best within $\lesssim2σ$. Our findings emphasize that the LS-2HDM favors the CMS results consistently with the current experimental results. On the other hand, while one can accommodate also the CDF results in this model theoretically, up-to-date electroweak precision bounds on the oblique parameters $(S,T,U)$ together with the SM-like Higgs and LFU constraints exclude these solutions and our results for $W-$boson mass can be only as close as about $2σ$ to the CDF results.

hep-ph↗

arXiv2017

Exploratory study of X(4140) in QCD sum rules

In this work, we chose three molecular and three diquark-antidiquark currents with the quark content $c\bar{c}s\bar{s}$ and $J^{PC}=0^{++},1^{++},2^{++}$, and estimated the masses and the meson coupling constants of the ground states coupling to these currents in the framework of QCD sum rules. In operator product expansion, we considered the terms including dimension eight, and we performed pole contribution tests carefully. According to our results, all of these currents couple to the ground states with degenerate masses which are in 10 MeV vicinity of X(4140). Therefore, with a QCD sum rules analysis, it is not possible to conclude that X(4140) has a dominant molecular or diquark-antidiquark content. However, there may be three states degenerate in mass, with positive charge conjugation and different isospins.

hep-ph↗

arXiv2012

Pair production of single and double charged scalar pairs and their lepton flavor violating signals in the littlest Higgs model at LHC

In this work productions of charged and doubly charged scalars and their lepton flavor violating collider signals in the framework of littlest Higgs model at LHC are studied. In the allowed parameter region of the littlest Higgs model, the production rates of the scalars of littlest Higgs model via $pp \to ϕ^{++}ϕ^{-}$, $pp \to ϕ^+ϕ^-$ and $pp \to ϕ^{++}ϕ^{--}$ processes are calculated. We obtained that charged and doubly charged scalar pairs can be produced at LHC . Considering the possible lepton flavor violating decays of charged scalars found in literature, final state analysis is done. This analysis show that depending on the model parameters, lepton number and lepton flavor violations resulting from single and double charged heavy scalars of the littlest Higgs model can be observed at LHC.

hep-ph↗