Search

We have estimated the sensitivity to the anomalous couplings of the γγγZ vertex in the γγ → γZ 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 $\gamma\gamma\gamma\gamma$ 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 $\zeta_1$ and $\zeta_2$ 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 $\gamma\gamma\gamma\gamma$ vertex., Comment: 20 pages, 8 figures. Figures 2-11 are combined as 2-7, tables 2-6 are combined as tables 2-3. Equation (16) is corrected, equations (17), (18), and one reference are added. Abstract is corrected. Version accepted for publication in EPJ C

The virtual production of axion-like particles (ALPs) in the light-by-light scattering at the CLIC collider is studied. Both differential and total cross sections are calculated, assuming interaction of the ALP with photons via CP-odd term in the Lagrangian. The 95\% C.L. exclusion regions for the ALP mass and its coupling constant are given. By comparing our results with existing collider bounds, we see that the ALP search at the CLIC has a great physics potential of searching for the ALPs, especially, in the mass region 1 TeV -- 2.4 TeV, with the collision energy $\sqrt{s} = 3000$ GeV and integrated luminosity $L = 5000$ fb$^{-1}$ for the Compton backscattered initial photons. In particular, our limits are stronger that recently obtained bounds for the ALP production in the light-by-light scattering at the LHC., 32 pages, 13 figures. Introduction is reduced, figure 11 is corrected. Appendix, several references and some comments are added

The photon-induced dimuon production $e^+ e^- \to e^+ \gamma \gamma e^- \to e^+ \mu^+ \mu^- e^-$ at the CLIC is studied in the framework of three models with extra dimensions. The electron beam energies 750 GeV and 1500 GeV are considered. The total cross sections are calculated depending on the minimal transverse momenta of the final muons. The sensitivity bounds on the parameters of the models are obtained as functions of the CLIC integrated luminosity., Comment: 37 pages, 19 figures. Several formulas with comments are added. Figures 13 and 14 are corrected, figure 19 is added

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., 19 pages, 9 figures. Abstract is corrected. Several formulas are added. Figures 2,3 and 9 are combined into two figures 2 and 3. Summary plot is added. To be published in Chinese Physics C

We study the anomalous $WW\gamma$ couplings at the Compact Linear Collider through the processes $e^{+}e^{-}\to W^+W^-$, $e^{-}e^{+} \to e^{-} \gamma^{*} e^{+} \to e^{+} \nu_{e} W^-$ and $e^{-}e^{+}\to e^{-} \gamma^{*} \gamma^{*} e^{+} \to e^{-} W^+ W^- e^{+} $ $ (\gamma^{*}$ 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., Comment: Tables and references added

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 \gamma \gamma p \to p \mu^- \mu^+p $ through the subprocess $\gamma \gamma \to \mu^- \mu^+$ is examined for two forward detector acceptances, $0.0015 < \xi< 0.5$ and $0.1< \xi, Comment: 22 pages, 8 figures; 11 equations and 8 references are added

WOS: 000441762300052, In this study, we investigate the potential of the process pp -> p gamma*p -> p tau(nu) over bar (tau)q' 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 alpha(tau) and vertical bar d(tau)vertical bar compared to the current experimental sensitivity bounds. The gamma p mode of photon reactions at the LHC have shown that it has great potential for the electromagnetic dipole moments studies of the tau lepton. (C) 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3)., Scientific and Technological Research Council of Turkey (TUBITAK) [115F136], This work has been supported by the Scientific and Technological Research Council of Turkey (TUBITAK) in the framework of Project No. 115F136.

WOS: 000413405200022, We have examined the anomalous electromagnetic moments of the tau lepton in the processes e(-)gamma -> nu(e)tau(nu) over bar tau (gamma is the Compton backscattering photon) and e(-)e(+)-> e(-)gamma*e(+) -> e(-)gamma -> nu(e)tau(nu) over bar tau (gamma* 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. (C) 2017 The Authors. Published by Elsevier B.V., Scientific and Technological Research Council of Turkey (TUBITAK) [115F136], This work has been supported by the Scientific and Technological Research Council of Turkey (TUBITAK) in the framework of Project No. 115F136.

We have examined the constraints on the anomaloustqγ (q=u,c)couplings through the processpp→pγp→pWbXat the LHC by considering four forward detector acceptances:0.0015<ξ<0.5,0.0015<ξ<0.15,0.015<ξ<0.15, and0.1<ξ<0.5, whereξ=Eγ/EwithEγandEthe energies of the photon and of the incoming proton, respectively. 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.

We have investigated real graviton emission in the ADD and RS model of extra dimensions through the photoproduction process pp-> p gamma p-> pGqX at the LHC. We have considered all contributions from the subprocesses gamma q -> G q, where q=u,d,c,s,b,anti-u,anti-d, anti-c, anti-s, anti-b quark. The constraints on model parameters of the ADD and RS model of extra dimensions have been calculated. During numerical calculations we have taken account of 3, 4, 5 and 6 large extra dimensional scenarios. The constraints on RS model parameters have been calculated by considering G -> gamma gamma, e^- e^+, mu^- mu^+ decay channels of the graviton., 27 pages, 12 figures; final version to appear in PRD

We have examined TeV scale effects of extra spatial dimensions through the processes $\ensuremath{\gamma}q\ensuremath{\rightarrow}\ensuremath{\gamma}q$, where $q=u$, $d$, $c$, $s$, $b$, $\overline{u}$, $\overline{d}$, $\overline{c}$, $\overline{s}$, $\overline{b}$. These processes have been treated in a photon-proton collision via the main reaction $pp\ensuremath{\rightarrow}p\ensuremath{\gamma}p\ensuremath{\rightarrow}p\ensuremath{\gamma}qX$ at the LHC. We have employed the equivalent photon approximation for incoming photon beams and performed statistical analysis for various forward detector acceptances.

We examine the impact of electromagnetic properties of neutrinos on the annihilation of relic neutrinos with ultra high energy cosmic neutrinos for the $\nu \bar{\nu}\to \gamma\gamma$ process. For this process, photon-neutrino decoupling temperature is calculated via effective lagrangian model beyond the standard model. We find that photon-neutrino decoupling temperature can be importantly reduced below the QCD phase transition with the model independent analysis defining electromagnetic properties of neutrinos., Comment: 12 pages, 3 figures, published version

WOS: 000302149500017, The potential of pp -> p gamma gamma p -> pGp process in scenarios of the Arkani-Hamed, Dimopoulos, Dvali (ADD) and Randall-Sundrum (RS) model at the LHC is examined, and 95% C.L. bounds on the model parameters are obtained. It is found that the sensitivity of the model parameters can be improved in the present colliders by using this reaction.

WOS: 000296889600005, We study the potential of processes pp -> p gamma gamma p -> pt (t) over barp in scenarios of the Arkani-Hamed-Dimopoulos-Dvali and the Randall-Sundrum model at the LHC. We obtain 95% C. L. bounds on the model parameters. We show top quark spin asymmetry can be detected and discerned from the standard model with these extra dimensional models.

WOS: 000270667600069, The exclusive production pp --> pXp is known to be one of the most clean channels at the LHC. We investigate the potential of processes pp ->- pl(-)l(+)p and pp ->- p gamma gamma p to probe scalar and tensor unparticles by considering three different forward detector acceptances; 0.0015 < xi < 0.15, 0.0015 < xi < 0.5 and 0.1 < xi < 0.5. We obtain 95% confidence level sensitivity limits on the unparticle couplings for various integrated luminosities.