arXiv subjects
Publications and source records attributed to S. C. İnan.
A production of a pair of tau leptons in PbPb collisions at the FCC-hh collider is examined. The 95\% C.L. exclusion limits, as well as 3$σ$ and 5$σ$ sensitivity limits on the anomaly magnetic moment of the tau lepton $a_τ$ and its electric dipole moment $d_τ$ are obtained. A comparison with bounds on $a_τ$ and $d_τ$ for other future colliders are given.
A sensitivity of the collider FCC-hh to anomalous quartic gauge couplings (aQGCs) of neutral bosons in lead-lead collisions is studied. Examining diphoton production, the bounds on aQGCs at $5σ$ and 95\% C.L. are obtained depending on systematic uncertainties.
We examine a contribution of axion-like particles (ALPs) to a top pair production via the collision of Compton backscattered photons at the CLIC operating in a $γγ$ mode. The exclusion bounds on the ALP-top quark coupling depending on the ALP mass $m_a$ are given. The mass range 10 GeV -- 10 TeV is considered. We have obtained that for $m_a = 10$ GeV the ALP-top quark couplings as small as $0.17$ TeV$^{-1}$ and $0.11$ TeV$^{-1}$ can be probed at the CLIC with the energy of 1.5 TeV and 3 TeV, respectively. A comparison with other constraints on the ALP-top coupling is given.
The sensitivity to anomalous quartic gauge couplings (AQGCs) of the $γγγZ$ interaction is studied in the $μ^+μ^- \rightarrow μ^+γγμ^-$ scattering at a future muon collider with unpolarized beams. The anomalous $γγγZ$ vertex is described by two couplings, $ζ_1$ and $ζ_2$. The differential and total cross sections are calculated for the center-of-mass energies of 3 TeV, 14 TeV, and 100 TeV. For these values of the collision energy the $95\%$ C.L. exclusion regions for AQGCs are obtained depending on the systematic error. In particular, for the 14 TeV muon collider with the integrated luminosity $L = 20$ ab$^{-1}$ the best sensitivities are derived to be $ζ_1 = 3.1 \times 10^{-5}$ TeV$^{-4}$ and $ζ_2 = 6.5 \times 10^{-5}$ TeV$^{-4}$. These constraints are three orders of magnitude stronger than the bounds obtained for the 27 TeV HE-LHC with $L = 15$ ab$^{-1}$. At the 100 TeV muon collider with $L = 1000$ ab$^{-1}$ AQGCs can be probed up to $(1.64 ÷3.4) \times 10^{-8}$ TeV$^{-4}$. The partial-wave unitarity constraints on couplings $ζ_1$, $ζ_2$ are evaluated. It is shown that the unitarity is not violated in the region of the AQGCs examined in the present paper.
We have examined inclusive $μ^+μ^- \rightarrow μ^+ μ^- + E_{\mathrm{miss}}$ and annihilation $μ^+μ^- \rightarrow μ^+ μ^-$ processes at future high energy muon colliders in the framework of the Randall-Sundrum-like model with a small curvature of space-time. The collision energies of 3 TeV, 14 TeV and, 100 TeV are addressed. Both differential and total cross sections are calculated, and exclusion bounds on a 5-dimensional gravity scale are obtained depending on collision energy and integrated luminosity of the muon colliders.
We have examined the sensitivity to the axion-like particle (ALP) couplings to electroweak gauge bosons in the diphoton production at a future muon collider. The collisions at the $μ^+ μ^-$ energies of 3 TeV, 14 TeV, and 100 TeV are addressed. The differential cross sections versus the invariant mass of the final photons and total cross section versus minimal diphoton invariant mass are presented. We have derived the exclusion regions for the ALP-gauge boson coupling. The obtained bounds are much stronger than the current experimental bounds in the ALP mass region 10 GeV -- 10 TeV. The partial-wave unitarity constraints on the ALP-gauge boson coupling are estimated. We have shown that the unitarity is not violated in the region of the ALP coupling studied in the present paper.
The noncommutative QED (NCQED) has a non-Abelian nature due to the presence of 3- and 4-photon vertices in the lagrangian. Thus, NCQED predicts a new physics contribution to the $γγ\rightarrowγγ$ scattering already at the tree level. We have examined NCQED by studying the light-by-light process at the 14 TeV LHC with intact protons. Our results show that the NC scale up to $Λ_{\mathrm{NC}} = 1.65(1.35)$ TeV can be probed in the $pp\rightarrow p(γγ)p \rightarrow p'(γγ)p'$ collision for the time-space (space-space) NC parameters. These bounds are stronger than the limits that can be obtained in the light-by-light scattering at high energy linear colliders.
For the first time, the production of a massive dark photon (DP) in the $γe^-$ scattering at the future lepton colliders ILC, CLIC, and CEPC is examined. The invisible decay mode of the DP is addressed. We have studied both the unpolarized scattering and the collision of the Compton backscattered photons with the polarized electron. The missing energy distributions are shown. We have considered the wide range 10 GeV -- 1000 GeV of the DP mass $m_{A'}$. The excluded regions at the 95\% C.L. in the plane $(\varepsilon, m_{A'})$, where $\varepsilon$ is the kinetic mixing parameter, are obtained.
We have estimated the sensitivity to the anomalous couplings of the $γγγZ$ vertex in the $γγ\rightarrowγZ$ scattering of the Compton backscattered photons at the CLIC. Both polarized and unpolarized collisions at the $e^+e^-$ energies 1500 GeV and 3000 GeV are addressed, and anomalous contributions to helicity amplitudes are derived. The differential and total cross sections are calculated. We have obtained 95\% C.L. exclusion limits on the anomalous quartic gauge couplings (QGCs). They are compared with corresponding bounds derived for the $γγγZ$ couplings via $γZ$ production at the LHC. The constraints on the anomalous QGCs are one to two orders of magnitude more stringent that at the HL-LHC. The partial-wave unitarity constraints on the anomalous couplings are examined. It is shown that the unitarity is not violated in the region of the anomalous QGCs studied in the paper.
The anomalous quartic neutral couplings of the $γγγγ$ vertex in a polarized light-by-light scattering of the Compton backscattered photons at the CLIC are examined. Both differential and total cross sections are calculated for $e^+e^-$ collision energies 1500 GeV and 3000 GeV. The helicity of the initial electron beams is taken to be $\pm\,0.8$. The unpolarized and SM cross sections for the same values of helicities are also estimated. The 95\% C.L. exclusion limits on two anomalous photon couplings $ζ_1$ and $ζ_2$ are calculated. The best bounds on these couplings are found to be $6.85 \times 10^{-16} \mathrm{\ GeV}^{-4}$ and $1.43 \times 10^{-15} \mathrm{\ GeV}^{-4}$, respectively. The results are compared with the exclusion bounds obtained previously for the LHC and HL-LHC. It is shown that the light-by-light scattering at the CLIC, especially the polarized, has a greater potential to search for the anomalous quartic neutral couplings of the $γγγγ$ vertex.
The light-by-light (LBL) scattering with initial polarized Compton backscattered photons at the CLIC, induced by axion-like particles (ALPs), is investigated. The total cross sections are calculated, assuming CP-even coupling of the pseudoscalar ALP to photons. The 95\% C.L. exclusion region for the ALP mass $m_a$ and its coupling constant $f$ is presented. The results are compared with previously obtained CLIC bounds for the unpolarized case. It is shown that the bounds on $f$ for the polarized beams in the region $m_a = 1000 \mathrm{\ GeV} - 2000 \mathrm{\ GeV}$, with the collision energy 3000 GeV and integrated luminosity 4000 fb$^{-1}$, are on average 1.5 times stronger than the bounds for the unpolarized beams. Herewith, our CLIC bounds are stronger than all current exclusion regions for $m_a > 80$ GeV. In particular, they are more restrictive than the limits which follow from the ALP-mediated LBL scattering at the LHC.
In this paper, potential of the LHC to explore the phenomenology of the Randall-Sundrum-like scenario with the small curvature for the process $pp \to p γγp \to p μ^- μ^+p $ through the subprocess $γγ\to μ^- μ^+$ is examined for two forward detector acceptances, $0.0015 < ξ< 0.5$ and $0.1< ξ<0.5$. This process is known to be one of the most clean channels. The sensitivity bounds on the anomalous model parameters have been found at the $95\%$ confidence level for various LHC integrated luminosity values.
In this study, we investigate the potential of the process $pp\rightarrow pγ^{*} p\rightarrow p τ\barν_τq^{\prime} X$ at the LHC to examine the anomalous electromagnetic moments of the tau lepton. We obtain $95\%$ confidence level bounds on the anomalous coupling parameters with various values of the integrated luminosity and center-of-mass energy. The improved bounds have been obtained on the anomalous coupling parameters of electric and magnetic moments of the tau lepton $a_τ$ and $\vert$$d_τ$$\vert$ compared to the current experimental sensitivity bounds. The $γp$ mode of photon reactions at the LHC have shown that it has great potential for the electromagnetic dipole moments studies of the tau lepton.
We have examined the anomalous electromagnetic moments of the tau lepton in the processes $e^{-}γ\to ν_eτ\barν_τ$ ($γ$ is the Compton backscattering photon) and $e^{-}e^{+} \to e^{-}γ^* e^{+} \to ν_{e}τ\barν_τe^+$ ($γ^*$ is the Weizsacker-Williams photon) with unpolarized and polarized electron beams at the CLIC. We have obtained 95$\%$ confidence level bounds on the anomalous magnetic and electric dipole moments for various values of the integrated luminosity and center-of-mass energy. Improved constraints of the anomalous magnetic and electric dipole moments have been obtained compared to the LEP sensitivity.
We have investigated the anomalous quartic couplings defined by the dimension-8 operators in semileptonic decay channel of the $e^{+}e^{-}\rightarrow ν_{e} W^{-} W^{+} \barν_{e}$ process for unpolarized and polarized electron (positron) beam at the Compact Linear Collider. We give the $95\%$ confidence level bounds on anomalous $\frac{f_{S0}}{Λ^{4}}$, $\frac{f_{S1}}{Λ^{4}}$ and $\frac{f_{T0}}{Λ^{4}}$ couplings for various values of the integrated luminosities and center-of-mass energies. The best sensitivities obtained on anomalous $\frac{f_{S0}}{Λ^{4}}$, $\frac{f_{S1}}{Λ^{4}}$ and $\frac{f_{T0}}{Λ^{4}}$ couplings through the process $e^{+}e^{-}\rightarrow ν_{e} W^{-} W^{+} \barν_{e}$ with beam polarization at $\sqrt{s}=3$ TeV and an integrated luminosity of $L_{int}=2000$ fb$^{-1}$ are $[-4.05;\, 3.67]\times 10^{-12}$ GeV$^{-4}$, $[-3.08; \, 2.12]\times 10^{-12}$ GeV$^{-4}$, $[-1.98; \, 0.64]\times 10^{-13}$ GeV$^{-4}$, which show improvement over the current bounds.
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.
We have investigated the flavor changing top quark physics on the dimension-six anomalous $tqγ$ ($q=u,c$) couplings through the process $pp\to pγγp\to p t\bar{q}p$ at the LHC by considering different forward detector acceptances. In this paper, we have taken into account and examine the effects of top quark decay. The sensitivity bounds on the anomalous couplings and, $t\to qγ$ branching ratio have been obtained at the $95\%$ confidence level for the effective lagrangian approach. Besides, we have investigated the effect of the anomalous couplings on single top quark spin asymmetry.
We have examined the constraints on the anomalous $tqγ$ ($q=u,c$) couplings through the process $pp\to pγp\to pWbX$ at the LHC by considering three forward detector acceptances: $0.0015< ξ< 0.5$, $0.0015< ξ<0.15$ and $0.1< ξ< 0.5$. The sensitivity bounds on the anomalous couplings have been obtained at the $95%$ confidence level in a model independent effective lagrangian approach. We have found that the bounds on these couplings can be highly improved compared to current experimental bounds.