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In this study, neutron-emission spectra produced by (n,xn) reactions on nuclei ²³²Th have been calculated. Angle-integrated cross-sections in neutron induced reactions on targets ²³²Th have been calculated at the bombarding energies from 2 MeV to 18 MeV. We have investigated multiple pre-equilibrium matrix element constant from internal transition for ²³²Th(n,xn) neutron emission spectra. In the calculations, the geometry dependent hybrid model and the cascade exciton model including the effects of pre-equilibrium have been used. Pre-equilibrium direct effects have been examined by using full exciton model. In addition, we have described how multiple pre-equilibrium emissions can be included in the Feshbach–Kerman–Koonin (FKK) fully quantum-mechanical theory. By analyzing (n,xn) reaction on ²³²Th, with the incident energy from 2 MeV to 18 MeV, the importance of multiple pre-equilibrium emission can be seen clearly. All calculated results have been compared with experimental data. The obtained results have been discussed and compared with the available experimental data and found agreement with each other.

An extraction of the parton distributions of the proton by a next-to-leading order QCD fit in the framework of the Standard Model is presented. The fit implements a novel decomposition of the quark species into up- and down-type quark distributions, which is the key to enable a determination of flavor separated parton distributions from a single experiment. The fit is performed on the inclusive unpolarized neutral and charged current cross-section measurements by the H1 collaboration at HERA. The discussion of uncertainties of parton distribution functions is based upon but extends the QCD analysis published together with the H1 data.

We have studied a top-Higgs production process in the topcolor assisted technicolor (TC2) model. The studies show that the production cross-section of is at the order of magnitude 10 fb in reasonable parameters space of TC2 model. A few hundred events of top-Higgs can be produced each year at the high energy linear e⁺e^- colliders (LC). The top-Higgs may be directly observed via this process.

We study the associated production of the neutral top-pion with the third family quarks within the context of the topcolor-assisted technicolor model at the hadron colliders. The studies show that, at the Tevatron, the cross-sections of all these processes are too small to produce enough identified signals. But the cross-sections can be largely enhanced at the LHC. Specially for the processes and , the cross-sections can reach the level of a few hundred fb even a few pb for the light neutral top-pion. With the high yearly luminosity 100 fb^-1 at the LHC, over 10⁴ signals can be produced via the above two processes. There exists an ideal flavor-changing mode to detect neutral top-pion, i.e. , because the SM background of such production mode are very clean. Therefore, we can conclude that neutral top-pion should be observable at the LHC via the processes and . On the other hand, the statistics available at the LHC via these two processes might be enough to measure the Yukawa couplings and . Finally, it must be noted that the study of the process can give us a good chance to distinguish the TC2 model from the SM and MSSM because there does not exist such similar tree-level favor-changing process in these models.

In this paper, a simultaneous analysis of the elastic scattering data of the ¹⁶O+¹⁶O system for the energy range 5–10 MeV/nucleon is performed theoretically within the framework of the optical model formalism, by using the α–α double folding cluster potential. The α–α double folding cluster potential is evaluated by using the α-cluster distribution densities in the usual nucleon–nucleon double folding process with an effective α–α interaction potential. The results of the α–α double folding cluster potential analysis are compared with the findings of the phenomenological Woods–Saxon squared and nucleon–nucleon double folding potentials. All potentials have exhibited a very good agreement with the experimental measurements for the elastic scattering angular distributions. Furthermore, it is shown that, the α–α double folding cluster potential and nucleon–nucleon double folding potential calculations provide very consistent results with each other. Thus, the ¹⁶O+¹⁶O system has been described by optical potentials having a deep real potential part and a weak absorptive imaginary potential part.

We consider the production of magnetic monopoles via γγ fusion at high energy pp collisions. In the assumption that the monopole spin is equal 0, 1/2, 1, the monopole–antimonopole pair production cross-section by this mechanism at LHC energies is estimated and analyzed.

T2K is the first of a new generation of long baseline neutrino oscillation experiments that will measure neutrino oscillations parameters. The experiment uses the J-PARC accelerator complex on the east cost of Japan to sent a neutrino beam to the Kamioka mine, located 295 km to the west. It consists of a dedicated beam-line, a near detector complex to characterize the beam and the well-known Super-Kamiokande detector to measure the oscillation signal. This paper describes the experimental setup, the results of the first measurement campaign as well as giving an outlook on the future potential of the experiment.

Recent measurements in the top quark sector at the Fermilab Tevatron collider are discussed. Measurements at the Tevatron use up to 9.7 fb^-1 of data corresponding to the full data sets recorded by each of the experiments, CDF and DØ. This review discusses the most recent measurements of inclusive and differential top quark cross-sections in strong and electroweak production of top quarks and related measurements, as well as measurements of angular distributions related to asymmetries in top quark production. Furthermore, the current status of precision measurements of the mass of the top quark is discussed. Where available, combinations of CDF and DØ results are presented.

We have studied the fusion of ¹¹Be with ²⁰⁹Bi and ¹⁵C with ²³²Th in the energy region around the barrier within the framework of quantum diffusion approach and have found enhancement in fusion cross-section in deep sub-barrier region and a very minor suppression in the above barrier energy region with respect to the corresponding experimental observations. The fusion cross-section is found to be slightly increased for reactions involving ¹¹Be and ¹⁵C nuclei in comparison to those involving the stable ¹⁰Be and ¹²C isotopes, respectively.

The CMD-3 detector has been taking data since December 2010 at the VEPP-2000 electron–positron collider. The collected data sample corresponds to about 60 inverse picobarn of integrated luminosity in the c.m. energy range from 0.32 GeV to 2.0 GeV. Preliminary results of the analysis of various hadronic cross-sections, in particular, $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}$, ${\pi }^{+}{\pi }^{-}{\pi }^0$, $K_L{K}_S$, $K^{+}{K}^{-}$, $\eta \gamma$, 3$({\pi }^{+}{\pi }^{-})$, $2({\pi }^{+}{\pi }^{-}{\pi }^0)$, $K^{+}{K}^{-}{\pi }^{+}{\pi }^{-}$, $K^{+}{K}^{-}\eta$, $K^{+}{K}^{-}{\pi }^0$, $\eta {\pi }^{+}{\pi }^{-}$, $\omega {\pi }^{+}{\pi }^{-}$ and $\omega \to {\pi }^0{e}^{+}{e}^{-}$ are presented. The processes with multi-hadron final states have several intermediate states which have to be taken into account to correctly describe the angular and invariant mass distributions, as well as cross-section energy dependence.

In the framework of the left–right twin Higgs (LRTH) model, we investigate the single top partner production at lepton colliders. We calculate the production cross-sections of the processes $e^{-}\gamma \to {\nu }_{e}b\bar{T}$, $e^{-}{e}^{+}\to W^{-}\bar{b}T$$(W^{+}b\bar{T})$ and $\gamma \gamma \to W^{-}\bar{b}T$$(W^{+}b\bar{T})$ at $\sqrt{s}=2.0$ TeV, and display some typical differential distributions of the final state particles.

Our purpose in this paper is to modify the original proximity potential by universal function available in the literature. A potential model with Yukawa proximity potential has been considered according to the modified model fusion reactions of ${}^{92}\mathrm{\text{Zr}}+{}^{12}\mathrm{\text{C}}$, ${}^{16}\mathrm{\text{O}}+{}^{92}\mathrm{\text{Zr}}$, ${}^{28}\mathrm{\text{Si}}+{}^{92}\mathrm{\text{Zr}}$, ${}^{16}\mathrm{\text{O}}+{}^{144}\mathrm{\text{m}}$, ${}^{28}\mathrm{\text{Si}}+{}^{28}\mathrm{\text{Si}}$, ${}^{28}\mathrm{\text{Si}}+{}^{29}\mathrm{\text{Si}}$, ${}^{28}\mathrm{\text{Si}}+{}^{30}\mathrm{\text{Si}}$, ${}^{24}\mathrm{\text{Mg}}+{}^{24}\mathrm{\text{Mg}}$, ${}^{24}\mathrm{\text{Mg}}+{}^{26}\mathrm{\text{Mg}}$ and ${}^{24}\mathrm{\text{Mg}}+{}^{28}\mathrm{\text{Si}}$, ${}^{26}\mathrm{\text{Mg}}+{}^{28}\mathrm{\text{Si}}$, ${}^{24}\mathrm{\text{Mg}}+{}^{30}\mathrm{\text{Si}}$, ${}^{26}\mathrm{\text{Mg}}+{}^{30}\mathrm{\text{Si}}$ which have been discussed in detail. The results have a good agreement with the experimental data.

The impact of higher-order matrix elements and ${\mu }_R$ and ${\mu }_F$ scales on the NLO K factors for ZZ vector boson pairs in proton–proton collisions are presented in this study. All predictions are performed using MCFM-8.0 Monte Carlo generator. First, the QCD predictions of ZZ production at LO and NLO accuracies are obtained using two most recent PDFs, MMHT2014 and CT14. To discuss the impact of higher-order matrix elements on the NLO K factors, both LO and NLO corrections are obtained by LO, NLO and NNLO matrix elements of these two most recent PDFs. Then, the impact of ${\mu }_R$ and ${\mu }_F$ scales on the NLO K factors are further discussed by using six different values of ${\mu }_R$ and ${\mu }_F$ in a range of $\frac{1}{2}{M}_Z\le {\mu }_R$, ${\mu }_F\le 2M_Z$, where $M_Z$ is Z boson mass.

The production of nuclear energy from fusion reaction with no CO₂ emission is one of the most attractive sources for the future. The unprecedented physical and mechanical properties for structural materials are very important in the nuclear fusion reactor design. So, tantalum material is a valuable candidate for plasma-facing materials in the fusion devices. In this paper, nuclear excitation functions for the ${}^{181}\mathrm{\text{Ta}}(p,n){}^{181}\mathrm{\text{W}}$, ${}^{181}\mathrm{\text{Ta}}(p,2n){}^{180}\mathrm{\text{W}}$, ${}^{181}\mathrm{\text{Ta}}(p,4n){}^{178}\mathrm{\text{W}}$, ${}^{181}\mathrm{\text{Ta}}(d,2n){}^{181}\mathrm{\text{W}}$, ${}^{181}\mathrm{\text{Ta}}(\alpha ,n){}^{184}\mathrm{\text{Re}}$ and ${}^{181}\mathrm{\text{Ta}}(\alpha ,2n){}^{183}\mathrm{\text{Re}}$ reactions are obtained using the nuclear codes TALYS 1.8 and ALICE/ASH. The contribution of pre-equilibrium and equilibrium processes in these reactions is investigated. In the calculations, the Weisskopf–Ewing and Hauser–Feshbach formalisms for the equilibrium particle emission, and the two-component exciton, hybrid and geometry-dependent hybrid formalisms for the pre-equilibrium particle emission are used. Hence, the cross-sections calculated are compared with the measured values. It is observed that the cross-section results of the geometry-dependent hybrid model match fairly well with the experimental measurements.

Using the quantum theory of linearized gravity, gravitational interaction differential cross-sections of one fermion by another fermion, a photon and a scalar particle are calculated in the fermion rest frame. Then, according to the obtained results, it is shown that in the lab frame, the gravitational interaction depends on the spin of the moving particle and is independent of the spin of the rest particle. After that, on the dependency of the gravitational interaction of fermion–photon upon the various states of photons, polarization is discussed.

A theoretical study of nuclear level density of Thorium nuclei that exist on and off the beta-stability line is carried out using Talys 1.6. The level density parameter a and spin cut-off factor $\sigma$ for Thorium isotopes ${}^{216-270}$Th are estimated. The values of both these parameters decrease towards the neutron drip line and the proton drip line. Cross-sections for $(n,p)$ and $(n,\alpha )$ reactions for Thorium isotopes are also calculated. The estimated and experimental values of cross-sections for ${}^{232}$Th are comparable. These evaluated data are useful in understanding the mechanism of nuclear reactions taking place under extreme conditions including those in nucleosynthesis.

In this work, the proton induced fission reaction cross-sections and fission yields are calculated for some actinides $({}^{232}\mathrm{\text{Th}}$, ${}^{233,235,236,238}\mathrm{\text{U}}$, ${}^{237}\mathrm{\text{Np}}$, and ${}^{239}\mathrm{\text{Pu}})$ using the fission barrier models of the TALYS 1.95 code. Cross-sections and fission yield calculations are carried out up to 100 MeV incident proton energies. The calculation results are compared with the available experimental data in the EXFOR library. In addition, a relative variance analysis of fission barrier models was done to determine the fission barrier model whose results best matched with the experimental results. Among the fission barrier models, the best agreement with the experimental data is obtained from the rotating-finite-range fission barrier model calculation for the $(p,f)$ reaction of the studied nuclei having the atomic mass number larger than 230. On the other hand, fission barrier heights for the studied reactions are determined using the same models.

Since it was reported that several radioisotopes might be advantageous for different medical uses in diagnostics and therapeutics, they have gained significance. Theoretical and experimental researches on such radioisotopes have contributed to the literature on a wide variety of topics, including production route research, getting activation and yield values, optimum production method analysis, clinical effects and production cross-section calculations. This study was motivated by the studies described in this domain as well as those published in the literature. The primary purpose of this study is to investigate the effects of deuteron optical model potentials in various reactions where ${}^{66\text{-}68}\mathrm{\text{Ga}}$ radioisotopes, which are known to be medically important, have been generated with deuteron induced particles on ${}^{\mathrm{\text{nat}}}\mathrm{\text{Zn}}$ and ${}^{\mathrm{\text{nat}}}\mathrm{\text{Ge}}$ targets. The experimental data from the literature and the calculation results generated using the five deuteron optical model potentials accessible in the TALYS code (version 1.95) were compared in line with the objective of this study. The experimental results in the literature and the data obtained as an outcome of the computations are graphically illustrated in order to comprehend these comparisons. Furthermore, to perform a numerical assessment, mean weighted deviation and relative variance calculations were also performed.

The radiative capture ${}^{14}$C(p, $\gamma$)${}^{15}$N is analyzed within the framework of potential model (PM) and R-matrix framework. The capture cross-section was analyzed for non-resonant and resonant transitions within the pathways that involve radiative capture via electric dipole ($E1$), and magnetic dipole ($M1$) transitions. The non-resonant transitions include $E1$ via s- and d-wave capture. The resonant transitions include electric dipole ($E1$), and magnetic dipole ($M1$) from the three dominant resonant states above the threshold of p+${}^{14}$C to the ground state of ${}^{15}$N. Based on the total cross-section, the rates associated with p+${}^{14}$C $\to$${}^{15}$N+$\gamma$ have been analyzed. In this paper, the resonant capture rates dominate compared to the existing data because, at resonant energies the amplitude of the cross-sections have a dominant effect on the radiative capture rates within the T₉ = 1.

We report a measurement of the production cross section using dilepton events with jets and missing transverse energy in collisions at . Using 197 pb^-1 of data recorded by the upgraded Collider Detector at Fermilab (CDF II), we use two complementary techniques to select candidate events. The combined result yields a production cross section of which is consistent with the Standard Model.