SearcharxivSearch

arXiv subjects

V. Arı

Publications and source records attributed to V. Arı.

4 recordsLinked to original sources

Search for anomalous quartic $ZZγγ$ couplings in photon-photon collisions

The self-couplings of the electroweak gauge bosons are completely specified by the non-Abelian gauge nature of the Standard Model (SM). The direct study of these couplings provides a significant opportunity to test the validity of the SM and the existence of new physics beyond the SM up to the high energy scale. For this reason, we investigate the potential of the processes $γγ\rightarrow ZZ$, $e^{-}γ\rightarrow e^{-}γ^{*}γ\rightarrow e^{-}Z\, Z$ and $e^{+}e^{-} \rightarrow e^{+}γ^{*} γ^{*} e^{-} \rightarrow e^{+}\, Z\, Z\, e^{-}$ to examine the anomalous quartic couplings of $ZZγγ$ vertex at the Compact Linear Collider (CLIC) with center-of-mass energy $3$ TeV. We calculate $95\%$ confidence level sensitivities on the dimension-8 parameters with various values of the integrated luminosity. We show that the best bounds on the anomalous $\frac{f_{M2}}{Λ^{4}}$, $\frac{f_{M3}}{Λ^{4}}$, $\frac{f_{T0}}{Λ^4}$ and $\frac{f_{T9}}{Λ^4}$ couplings arise from $γγ\rightarrow ZZ$ process among those three processes at center-of-mass energy of 3 TeV and integrated luminosity of $L_{int}=2000$ fb$^{-1}$ are found to be $[-3.30;3.30]\times 10 ^{-3}$ TeV$^{-4}$, $[-1.20;1.20]\times 10 ^{-2}$ TeV$^{-4}$, $[-3.40;3.40]\times 10 ^{-3}$ TeV$^{-4}$ and $[-1.80;1.80]\times 10 ^{-3}$ TeV$^{-4}$, respectively.

hep-ph

Search for excited spin-3/2 neutrinos at LHeC

We study the potential of the next $ep$ collider, namely LHeC, with two options $\sqrt{s}=1.3$ TeV $\sqrt{s}=1.98$ TeV, to search for excited spin-1/2 and spin-3/2 neutrinos. We calculate the single production cross section of excited spin-1/2 and spin-3/2 neutrinos according to their effective currents describing their interactions between gauge bosons and SM leptons. We choose the $ν^{\star}\rightarrow eW$ decay mode of excited neutrinos and $W\rightarrow jj$ decay mode of $W$-boson for the analysis. We put some kinematical cuts for the final state detectable particles and plot the invariant mass distributions for signal and the corresponding backgrounds. In order to obtain accessible limits for excited neutrino couplings, we show the $f-f^{\prime}$ and $c_{iV}-c_{iA}$ contour plots for excited spin-1/2 and excited spin-3/2 neutrinos, respectively.

hep-ph

Anomalous $WWγ$ couplings with beam polarization at the Compact Linear Collider

We study the anomalous $WWγ$ couplings at the Compact Linear Collider through the processes $e^{+}e^{-}\to W^+W^-$, $e^{-}e^{+} \to e^{-} γ^{*} e^{+} \to e^{+} ν_{e} W^-$ and $e^{-}e^{+}\to e^{-} γ^{*} γ^{*} e^{+} \to e^{-} W^+ W^- e^{+} $ $ (γ^{*}$ is the Weizsacker-Williams photon). We give the 95\% confidence level limits for unpolarized and polarized electron (positron) beam on the anomalous couplings for various values of the integrated luminosities and center-of-mass energies. We show that the obtained limits on the anomalous couplings through these processes can highly improve the current experimental limits. In addition, our limits with beam polarization are approximately two times better than the unpolarized case.

hep-ph

Search for $HZZ'$ couplings at the LHC

New physics models predict the possibility of extra neutral gauge bosons ($Z'$) associated with an extra $U(1)'$ gauge symmetry. We study the couplings of the Higgs boson to the $Z$ boson and $Z'$ boson predicted by the new physics models. The couplings of the $Z'$ boson to quarks can also be investigated through the $Z'q\bar{q}$ interactions. The accessible ranges of the parameter space have been searched for processes $pp\rightarrow HZX$ and $pp\rightarrow HHZX$ at the LHC with $\sqrt{s}=14$ TeV.

hep-ph