The Future Circular Collider ((FCC-ee)), with its clean experimental environment, high energy, and luminosity, offers a unique opportunity for the precise study of the properties and interactions of top quarks. In this study, we have investigated the potential sensitivity of the (FCC-ee) to Flavor-Changing Neutral Current ((FCNC)) processes involving top quarks using an effective Lagrangian approach. To this end, the production of top quarks in electron-positron collisions at center-of-mass energies of 240 GeV and 365 GeV has been simulated, considering the full hadronic decay of the W boson resulting from the top quark decay. The results of the analyses show that by combining these center-of-mass energies and considering integrated luminosities of 5 ab⁻¹ and 1.5 ab⁻¹, an (FCNC) sensitivity on the order of 10⁻⁵ can be achieved. These findings highlight the significant potential of the (FCC-ee) for discovering and precisely studying (FCNC) processes, which could contribute to a better understanding of physics Beyond the Standard Model.

In this paper, we present a detailed study to probe top-quark flavor changing Neutral Current ((FCNC)) interactions at, , and vertices with top-quark pair in association with a photon and three-top-quarks signal at the Large Hadron Collider (LHC). We investigate the top-quark (FCNC) couplings and carry out a full simulation for the triple-top production considering the main backgrounds. In addition, having at hand the cross section of a top-quark pair produced in association with a photon in collisions at a centre-of-mass energy of 8 TeV with 20. 2 of data collected by the ATLAS detector, we also investigated the (FCNC) coupling. The obtained exclusion limits on coupling strengths and branching ratios are summarized and compared with the results in literature. The discovery potential for anomalous couplings, , and with an integrated luminosity of are also examined in detail. We show that, for higher luminosities within Run-II of LHC, a dedicated search for the top-quark (FCNC) couplings can achieve comparable or even better sensitivities to the triple-top signal than the other top-quark production scenarios. We have shown that the triple-top signal could potentially provide evidence for new physics at the LHC.

Since top quark has large Yukawa coupling, investigation the Higgs-top sector is highly interesting as it looks for any deviations from the Standard Model predictions. In this paper, we study the Higgs boson production in the gluon-gluon fusion channel and in the presence of top quark Flavor Changing Neutral Current ((FCNC)) interactions at the LHC. We utilize the Standard Model effective field theory framework to probe the new physics effects. The amplitude for Higgs boson production via (FCNC) interactions and the theoretical expression for its signal strength are calculated. Then, by comparing this theoretical expression with the experimental value reported by LHC collaborations, we find the allowed region for those (FCNC) couplings that play a role in Higgs boson production.

The study of polarized top quark decay could be considered as a new channel to search for new physics. According to the Standard Model (SM) of particle physics, top quark in a cascade process as decays into a bottom quark and -boson so in the following, -boson decays in a lepton pair (or a quark-antiquark) and bottom hadronizes into an observable bottom-flavored hadron (in most cases a B-meson). Through this paper, we first present an overview on the polarized top quark decay and then study the azimuthal correlation between the event plane, formed by the vectors , and the polar plane constructed by the vectors . We will investigate the effect of right-chiral quark Current which is absent in the SM. We will show that this non-SM effect leads to nonzero values for the azimuthal correlation contribution at leading-order perturbation theory.

Electron-positron annihilation experiments are crucial tools for testing the Standard Model due to the simplicity and clarity of the initial state. Several lepton Colliders, such as the Electron-Positron Circular Collider, the International Linear Collider, the Future Electron-Positron Circular Collider, and the Muon Collider, are being explored and constructed. One of the possible processes in these Colliders is electron-positron annihilation at high energies, processes such as , which is one of the important tools for testing the Standard Model due to the simplicity and clarity of the initial states. In this scenario, heavy quark pairs  are initially produced, which can subsequently directly fragment into heavy baryon pairs  and , respectively. In this paper, the fragmentation functions of heavy quarks b and c into triply heavy baryons and at the first order of perturbation are calculated using pQCD. Then, the branching Fractions of  boson to these baryons,  and , are calculated.

The existence of a new massive charged gauge boson, known as W’, is proposed by many new physics scenarios. When W’ decays to tb, the final state is very similar to the final state of the s-channel single top production, where W boson is the off-shell mediator to produce the top and bottom quarks. If W exists, it can affect the cross section of the SM schannel single top production, so measuring this cross section can constrain the W’ contribution. We use different data categories from CMS and ATLAS experiments to constrain this contribution. Assuming a pure left-handed (righthanded) W’ gives a lower limit of 1290 (1360) GeV at 95% Confidence Level on the mass of W’. If the coupling coefficient is increased to 1.8, the lower limit on the W’ mass can exceed 1900 GeV, in special cases.

Introduction: Weak decays of heavy quarks test the Standard Model and can be used to determine its parameters, including the weak mixing angles of the CKM matrix. In addition, the study of heavy quark decay provides important insight into the least well understood sector of the strong interaction. Decays of the b quark play a unique role for physics of the CKM matrix. This is also an important place to test our understanding of interplay between strong and weak interaction. Higher order decays of the b quark are also a sensitive window for physics Beyond the Standard Model. In the Standard Model, Flavor-Changing Neutral Currents are forbidden, for example, there is no direct coupling between the b quark and the s or d quarks. Effective Flavor-Changing Neutral Currents are induced by penguin diagrams, where a quark emits and reabsorbs a W, thus changing flavors twice. Penguin decays have become increasingly appreciated in recent years. These loop diagrams with their interesting combination of CKM matrix elements give insight into the Standard Models.Aim: Obtaining the second order approximation part of gluon penguin in various b quark and B Meson decays.Materials and Methods: In this research, we are going to study weak interaction, quark and Standard Models. According to Effective Hamiltonian Theory, we deduced various two and three body of B meson decays from various decays of b quark ModelsResults: The amplitude of decays of tree level and gluon penguin structure in quark Model up to the first and second orders approximation calculated. We calculated the amplitude of tree level plus gluon penguin on lowest order of the strong coupling constant as=0.2 for first order of the decay processes b®qi qk q̅j+qk qi q̅j̅ and for second order of the decay processes b® qi qk q̅j+qk qi q̅j̅ (qoq̅p) Also the decay rates of various decays of b quark up to the first and second orders approximation of the tree level plus penguin structure calculated.Conclusion: Comparing of theoretical and experimental values of decay rates and branching ratios, we consider that, the decay rate of the second order decays are much smaller than the first ones and the tree level dominated.Finally we compared the branching ratios of various decays of B meson, theoretically and experimentally and saw that the second order of gluon penguin term in b quark decays is small.

It is already more than a hundred years ago that the Natural Philosophy and Metaphysics parts of Avicenna’ s famous philosophical encyclopaedia al-Shifā ʾ (The Cure) were published by the printing house of the Dā r al-Funū n (‘ Polytechnic’ ) academy at Tehran. This printing, which is usually referred to as the ‘ Tehran lithographic edition’ , is a milestone in Avicenna studies based on Arabic sources. It increased the level of attention for The Cure at a national and international level. About half a century after publication of the above edition, the first three volumes of the Natural Philosophy (al-Ṭ abī ʿ iyyā t) part of The Cure were translated into Persian by Muḥ ammad ʿ Alī Furū ghī (b. 1294/1877, d. 1321/1942). It was this translation which incited the famous Iranian scholar Mī rzā Mahdī Mudarris Ashtiyā nī (b. 1306/1888-89, d. 1372/ 1952-53) to write a critical study of it, both textually and philosophically. Outside Iran, the physics of the Natural Philosophy part of The Cure was published four times: in Egypt, Lebanon, Turkey, and the United States. It is especially the Cairo printing (begun in the nineteen-fifties and the first of the editions just mentioned) which had a huge impact, especially among Arabists, who until then mostly had no knowledge of or interest in the Latin Avicenna tradition, which goes back some nine-hundred years. With the modern printings of the Arabic text and the studies and translations that are based on it, one could say that Avicenna truly ‘ went global’ for a second time, after his huge imprint on Western