بينش امروزي ما پيرامون جهان هستي مبتني بر مدل استاندارد ذرات بنيادي مي‌باشد. مطابق اين جهان از يك مجموعه فرميون‌هاي بنيادي اسپين 12   به نام كوارك‌ها و لپتون‌ها تشكيل شده است و برهم كنش‌هاي ميان اين سنگ‌هاي اوليه طبيعت عبارتند از: برهم كنش الكترومغناطيسي، برهم كنش هسته‌اي قوي، و برهمكنش هسته‌اي ضعيف است كه از طريق مبادله بوزون‌هاي پيمانه‌اي به نام فوتون، گلئونW±   و‏Z0   صورت مي‌گيرد. اين مدل در نيمه دوم قرن بيستم در نتيجه ي تلاش مشاركت آميز دانشمندان در عرصه جهاني شكل گرفت. فرمول بندي كنوني آن در اواسط دهه ???? ميلادي پس از تاييد تجربي وجود كوارك‌ها نهايي شد.

  Abstract:One of thequantities studied in the fission process is the mass distribution of thefission fragments. When fission occurs, fission fragments with different massesare created. In this thesis, the temperature dependence of the fission fragmentmass yield width for high excitation energies is investigated. The width of themass yield depends on the number of nucleons in the nuclei, the volume andsurface terms of the energy level density parameter, the temperature and thepotential stiffness parameter related to the degree of freedom of the massasymmetry. Calculations are done using the transition state fission model. Forfission of 201Tl, 207Bi, 210Po and 213Atnuclei, we will compare the results of theoretical calculations withexperimental data. Also, the contribution of the surface term of the energylevel density parameter in the width is investigated for differenttemperatures.Keywords: Fission fragment, Temperature dependence, Width of mass yield

   In this treatise,we investigate the unpolarized transverse momentum dependent (TMD) structure of light nuclei in the modified chiral quark exchange model (QEM), for the first time. To this end, we calculate the TMD quark and gluon distributions inside the bound state nucleons of the light nuclei based on the modified chiral quark model (cQM) in which the TMD bare quark distributions of the bounded nucleons are needed. In order to compute these bare distributions, we first obtain the bare quark momentum densities using the QEM and then calculate the TMD bare distributions applying a theoretical method in which the light-cone variables are used. Finally, considering the nucleon structure of helium, tritium and deuteron nuclei, we obtain their TMD quark and gluon densities at low Q2 scale. Finally, considering the nucleon structure of   14N - 12C -4He - 6Li   uclei, we obtain their TMD quark and gluon densities at low Q2 scale. Due to the unavailability of experimental results for such nuclei, we have examined the general behavior of the obtained distributions. It is shown that our results have appropriate properties that are expected for the TMD distribution functions. Keywords: EMC effect, chiral quark model, quark exchange model, transverse momentum, light nuclei      

D* meson in the non-relativistic state in the proton-proton collision at the energy of the center of mass ?S=7Tev through the fragmentation of heavy quarks and using the factorization theorem based on the QCD theory of disturbance in hadron colliders We have studied LHC. In this case, after the proton-proton collision,quark c emitted a gluon with spin one and created a quark-antiquark pair, and the desired meson is created from the combination of heavy quark and antiquark. In the first step, calculate the function and the probability of fragmentation for quark c and b in the initial scale of fragmentation. Then, by applying the factorization theorem, we have calculated the differential cross-sectional and the total cross-sectional of ??the production of these particles. And finally, we have studied the behavior of the differential pt

 Theproperties of the fusion barrier of actinide compound nuclei with atomic numberin the range of 90 ? Z ? 95 have been studied for different target andprojectile combinations. The mass numbers of these nuclei are in the range of228 ? A ? 244. The total interaction potential is considered as the sum ofCoulomb potential and nuclear potential. The height and radius of the fusionbarrier as well as the curvature of the fission barrier have been investigated.After calculating the height and radius of the fusion barrier, the formulationfor these quantities is presented, which will show their dependence on the massnumber and atomic number of the projectile and target. Using theseformulations, we have calculated the fusion cross section for the reactions 38S+181Ta, 32S+181Ta, 38S+208Pb, and 16O+208Pband compared with the experimental data.

   Entropy actually expresses the order of the system. We want to get the entropy for the neutron. If we consider the neutron in a non-disordered state (we consider the neutron to be composed of valence quarks), the maximum entropy is obtained from the distribution functions of valence quarks, but in the disordered state and small x, the gluon contribution is dominant, and the entropy is from the gluon distribution function Obtained. We get the entropy in the zeroth and first order of disorder. We can see that as Q2   increases, entropy increases. Then we compare the obtained entropies with the laboratory data in some specific Q2 and observe that the obtained entropy is in good agreement with the laboratory data.   

  AbstractObjective: The most effective way to summarize what we know about a complex system is to identify the potential impact effects of the interaction on that system, so it is essential to examine the potential effects of the interaction in real systems. On the other hand, in the last few decades, we have witnessed a revolution in the world that has been made by science and technology in connection with two-dimensional, one-dimensional and zero-dimensional nanostructured materials. The main context of the attractive and valuable phenomena of quantum structures is quantum confinement and confinement, and therefore research on the origin and effect of confinement in quantum dots has become one of the most basic and exciting introductory fields in modern science. The aim of this study is to study meson systems in quantum dots.Research Methodology: This research is fundamental in terms of type. Due to the confinement of a quark  under the potential of , along with a suitable boundary condition, the corresponding Schrodinger equation is obtained by approximating the effective mass (EMA). For the basic state, the solution and the energy of the base state, the wave function and the probability of the quark probability are obtained. Due to the similarity of mesonic systems to electron-hole system  and also due to the choice of potential parameter approach that has flexibility, this information is compared with quantum dots consisting of electrons and holes.Results: From the phenomenological analysis, it was observed that the assumption for the effective potential of , with a certain range of values "??

   So far a lot of   theoretical and experimental researchs on different two-dimensional monolayers in order to assess their structural stability, electronic properties and application in electronic devices.Nanostructures are materials with nanometer size, different physical, chemical, mechanical and… properties in comparison bulk of them.In material, with nanostructure size, the area atoms ratio to volume atoms is very bigger than bulk case. Also in these structures there are quantum confinement effects and there for properties of them are different from bulk materials.In this work, under the generalized gradient approximation (GGA), the structural and electronic properties of germanene with and without impurity by using the first-principles projector-augmented wave (FP-LAPW) potential within the density functiontheory (DFT) framework.   

  In this thesis, Complex Gradient Method is used to interpret the Self-Potential anomaly.This method is a fast and straightforward method for estimating parameters of the origin of self-potential anomaly by using horizontal and vertical derivatives of SP data simultaneously. Here, it is assumed that the bulk of the SP anomaly is a two-dimensional inclined sheet which its parameters are depth to upper edge, depth to bottom edge, dip angle and electrical dipole moment.The validity of the complex gradient method is proven by applying it to synthetic data, with and without adding noise, for cases in which some parameters are constant while the others are variable. The method is also applied to estimate model parameters for field data in three zones related to a copper mine in the Surda region of India, a copper sulfide mine in Sulymankoy, Turkey, and a graphite mine in Southern Bavarian in Germany. Comparing the results of the latter case with the results of other methods show that the complex gradient method well identifies the parameters of the self-potential source.It should be noted that the results obtained in this thesis were extracted from the coding in MATLAB software.

  in this article We investigate the structure of the light nuclei based on the modified chiral quark model (?QM. To this end, we first calculate the parton distribution functions (PDFs) of the bounded nucleons using the ?QM and then compute those of the light nuclei. For this purpose, it is first needed to obtain the bare quark densities inside the bounded nucleons of the nucleus. These bare distributions are calculated by applying the quark exchange model (QEM) in this article. Finally, we obtain the quark, antiquark, and gluon distributions and also the structure functions (SFs) of the bound state nucleons and the light nuclei at low Q2 scale (Q2 = 0.35 GeV2). These distributions can be evolved to the higher scales using DGLAP evolution equations. It is shown that the results of our theoretical framework are in good agreement with the experimental data

  It is thought that the internal structure of free nucleons with internal structure of bound nucleons inside the nucleus is the same. In 1362/1983 the research group EMC,using muon deep inelastic scattering experiment the nuclei, measured ratio of the iron nuclei structure functions to the deuteron nuclei structure function in nucleon unit, that on the contrary expectation is not one. This phenomenon is known as EMC effect that the indicates that the components distribution of   bound nucleus is different from the free nucleus. In this thesis is to investigate the quark exchange model and this model shows that in the range of middle x the quarks valance may have a the share in the EMC. But this model in large and small x range is not able to explain the EMC effect. For large x range، fermi motion have a major role and for small x range، quark exchange model is not comprise role of   the sea quarks and gluons in the structure function. In this thesis, using the quark constituent   exchange model is calculate share   sea quarks and gluons in the structure functions.

در اين پايان نامه، تابش هاي باردار به دو دسته تقسيم مي شود.گروه اول الكترون و پوزيترون و گروه دوم ذرات سنگين مانند ذرات آلفا،پروتون، ميون و ساير هسته هاي سنگين را دربرمي گيرد.براي محاسبه توان توقف پروتون و آلفا از رابطه بته بلاخ استفاده مي شود.ميزان اتلاف انرژي پروتون وآلفارا در ماهيچه،استخوان وبافت نرم با استفاده از نرم افزار ميپل محاسبه كرده ونتايج آن را با استفاده از نرم افزار اوريجين در نمودارها نشان داده شده است.توان توقف پروتون و آلفا را در آب و طلا بدون تصحيح وبا درنظر گرفتن تصحيح اثر چگالي محاسبه شده است.اثر چگالي در انرژي هاي بالا، باعث كاهش ميزان توان توقف مي شود.توان توقف پروتون و آلفا را در آلومينيوم بدون تصحيح و بادر نظر گرفتن تصحيحات اثر چگالي، باركاس و بلاخ نيز انجام داده شده است.بررسي ها نشان مي دهد كه توان توقف با تصحيح اثر باركاس و بلاخ در انرژي هاي پايين كاهش مي يابد. 

  The upsilon meson has a quark structure b . This meson has a spin-1 in the S-wave state, and it is possible to generate in the electron-positron annihilation. In this thesis, the direct production of upsilon was investigated by direct quark and anti-quark b and gluon fragmentation. Accordingly, considering the Fermi motion corrections and NLO corrections, the meson-upsilon cross section production is calculated around its mass and around the Z0 pole. The results are in good agreement with experimental data. Additionally, the Z0 decay rate has been calculated for the upsilon meson, taking into account the Fermi motion corrections and NLO corrections.

In this thesis, first we examine the existence of a sequence of weak solution for the non-local equation of the following fraction\\\\ ‎‎\\begin{cases}‎‎‎M\\Big(\\iint‎‎‎‎_{\\mathbb{R}^{2N}}\\frac{\\vert u(x)‎ -u (y)\\vert^{p}}{\\vert x‎ - ‎y\\vert^{N+ps}}dxdy\\Big)‎(-\\Delta)_{p} ‎^{s}u(x)=f(x,u)‎\\qquad‎\\qquad ‎in‎\\qquad‎\\Omega,\\\\‎  ‎‎‎ ‎u=0‎\\qquad‎\\qquad‎\\qquad‎\\qquad‎\\qquad‎\\qquad‎\\qquad‎\\qquad‎‎\\qquad‎‎\\qquad‎ ‎in‎\\qquad‎‎‎\\mathbb{R‎^{N}‎}‎‎\\backslash\\Omega, ‎‎‎\\end{cases}‎‎‎‎\\\\‎where ‎$ ‎\\Omega ‎$‎ ‎is ‎an ‎open ‎bounded ‎subset ‎of‎ ‎$ ‎\\mathbb{R‎^{N}‎} ‎$‎ ‎with ‎Lipshcitz ‎boundary‎ ‎$ ‎\\partial‎\\Omega‎ $‎,‎‎ ‎$ (-‎\\Delta)‎_{p}‎^{s}‎‎‎ $ ‎is ‎the ‎fractional ‎p-Laplacian ‎operator ‎with‎ ‎$ 0<  lt;1<  lt;N $ ‎such ‎that ‎‎‎$   lt;N $‎,‎‎ ‎‎$ M $ ‎is a‎ ‎continuous ‎function ‎and‎ ‎$ f $ ‎is a ‎‎Carat‎‎heodory ‎function ‎satisfying ‎the ‎Ambrosetti-Rabinowitz-type ‎condition‎. When ‎$ f $ ‎satisfies ‎the ‎suplinear ‎growth ‎condition,we ‎obtain ‎the‎ existence of a sequence of nontrivial solutions by using the symmetric mountan pass theorem; when ‎$ f $ ‎satisfies ‎the ‎sublinear ‎growth ‎condition, ‎we ‎obtain ‎infinitely ‎many ‎pairs ‎of ‎nontrivial ‎solutions ‎by ‎applying ‎the ‎Krasnoselskii ‎genus ‎theory. ‎Our ‎results ‎cover ‎the ‎degenerate ‎case ‎in ‎the ‎fractional ‎setting: ‎the ‎Kirchhoff ‎function‎ ‎$ M $ can be zero at zero. ‎Using Mountain pass theorem we prove the existence of infinitely many solutions for the above problem. Then we discuss the existence of infinitely many solutions for fractional equations with sign changing nonlinear terms via varational methods in fact if the nonlinear terms are sign changing and satisfy p-supper growth, we obtain the existence of infinitely many solutions for boundary value problems driven by fractional p-Laplacian.‎‎‎‎‎‎‎‎‎‎\\\\‎‎\\textbf{Keywords:} \\\\‎‎\\textit{Fractinal p-Laplacian‎, Kirchhoff problems‎, Differential operator‎, Mountain pass Theorem‎, Nonlocal operator‎, Variational methods‎, Weak solution‎ }‎\\end{latin}‎

Investigate of the weak contribution of nucleon structure functions 

  In this thesis ,we first calculated electric and magnetic form factors of proton   y investigating the scattering of electron- proton and   using rosenbluth formula.It is observed the form factors of proton decreased as   increases that is agreement with experimental results. Then by considering the   cattering of electron-deuteron and electron – helium3 the electric and magnetic form factors     of neutron was determined. The obtained results show that the neutron electric form factor is approximately zero while the magnetic form factor is consistent with form factor scaling .Also will due attention to calculated form factors of neutron , we found that in high energies ,the structure of neutron is affected by nuclear effects.  Keywords: scattering,cross section,form factors

  In this thesis, we study one of the modes of super-heavy elements decay, which is spontaneous fission decay.   A review of the various theories about this decay has been presented. Some features of these elements, such as fission barrier, kinetic energy of fission fragments, and spontaneous fission half-life will be analyzed.   We also compare the results of the theory of different quantities with empirical results.

  Inthis research, muon catalyzed fusion in solid systems D-T   (deuterium-tritium), H-D-T   (Hydrogen-deuterium-tritum) andthree-layer HT-D2-DT   are studied In particular the role of muonichelium atoms in all mentioned system has been inrestigated.Thepoint kinematic equtions are numerically solved to calculate muon cyclingcoefficient muon cycling rate and the effective sticking coefficient for theproposed system. The obtained results are compared with It is shown that themuon cycling coefficient in three-layer decrease. Also to consider muonichelium atoms in fusion cycling reduces fusion yield in mentioned systems.

As physicists, we want to understand how nature works. Therefore no matter what we calculate, eventually it has to agree with observations. If we want to claim we understand how particles interact with each other eventually we have to link our understanding to quantities that can be measured in experiments. This work has tried to explain some aspects of one of the means that particles can interact, which is via the strong interaction. This leads to many interesting effects but it can make it difficult to study in some regimes. In recent years moving together to provide results at strong coupling. String theory in AdS space is a great tool for studing non-perturbative aspects of QCD. According to AdS/CFT correspondence gravity theory in (d+1)-dim in AdS space is dual to a conformal theory in the d-dim boundary. So machinery of AdS/CFT can be applied to QCD, but QCD is not conformal and gravity dual to QCD is not known yet. Deep inelastic lepton-nucleon scattering (DIS) and Pomeron dynamics and structure functions is investigated at small x in the frame work of holographic quantum chromodynamics. Finally we study the dual scattering amplitude of 2? 2 scattering of hadrons through the exchange of a spin j field. The parameter length string   is fixed by requiring cross sectio   to have pomeron-like behavior   and   pomeron-like intercept.     Key Words: AdS/QCD duality, AdS/CFT correspondence, hard & soft wall model, pomeron exchange  

supersymmetry 

 quarkonium production

Ternary fragmentation by calculating the potential energy surfaces (PES)with the inclusion of deformation and orientation degrees of freedom forthe 4He- and 10Be-accompanied fission of the 252Cf nucleus is studied. most favored ternary fragmentation channels in the light charged particles(4He and/or 10Be)-accompanied fission of the 252Cf nucleus are predictedusing the PES calculations. The sensitivity of PES due to the groundstate quadrupole deformation (?2) and the orientation effects (90?–90? and0?–0?) of the fragments are analyzed.

A fully quantum mechanical model of two-component Manakov solitons is developed in both the Heisenberg and Schr?dinger representations, followed by an analytical, linearized quantum theory of Manakov solitons in the Heisenberg picture. This theory is used to analyze the vacuum-induced fluctuations of Manakov soliton propagation and collision. The vacuum fluctuations induce phase diffusion and dispersion in Manakov soliton propagation. Calculations of the position, polarization angle, and polarization state fluctuations show an increase in collision-induced noise with a decrease in the relative velocity between the two solitons, as expected because of an increase in the interaction length. Fluctuations in both the polarization angle and state are shown to be independent of propagation distance, opening up possibilities for communications, switching, and logic, exploiting these properties of Manakov solitons.

Air pollution is one of the most important recent environmental problems which is the presence of gaseous, liquid, and solid compounds or a mixture of them in the air. Therefore; it can endanger human health directly or indirectly and it also causes harm to animals, plants, buildings and bodies.  The main air pollutants include particulate matters and gases. Particulate matters are solid or liquid particles that are suspended in a gas (usually air). Since particulate matter pollutant nowadays have become a critical pollutant of metropolises , the evaluating of particulate matters concentration in indoor and outdoor environments in Kermanshah province has became necessary. The results of extensive studies on indoor air pollution indicate that the effect of air pollution in indoor environments is more than air pollution in urban environments, as most people in the urban community spend about 80% to 90% of work and life time in indoor environments and are exposed to air pollution in these environments. As a result, this study aimed at investigating significant indoor pollutants, their sources and their effects on health, the introduction of some of the indoor pollutants resources and the study of the limitations of indoor pollutants in the world as well as Iran. As Kermanshah province is the second province that is involved with the dust storm, and the quality of indoor air is influenced by out, this study examined the indoor air quality using Lighthouse HANDHELD 3016 Particle Counter under dusty and clean conditions, in the environments equipped with water and gas air conditioners over 5 minute periods (22 time cycles).  The results of the research showed that in all measurements, the particles with the diameter of 0.3, 0.5 and 1 micron had the most frequency, respectively. Also, as particles with a diameter of more than 1 micron (very large particles) can enter the atmosphere through dust, by making comparison between the number of particles with a diameter greater than 1 micron in the indoor environments equipped with water and gas air conditioners under dusty and clean conditions, it was found that these particles in dust conditions in environments with water conditioners increased up to 3 times in some cases than those in gas air conditioners. That is to say, water air conditioners bring much more dust particles into indoor environments. Regarding various studies, photocopiers and printers can be considered as an important source of particulate matters (ultrafine and fine particles) in office environments. In order to investigate this, the concentration of particles 0.3, 0.5, 1, 5, and 10 micrometers in diameter was measured before the devices were turned on, as well as during the operation of the machines in the printing office with the largest number of photocopiers and printers in Kermanshah province. The results showed a significant increase in the concentration of 0.3, 0.5 and 1 micron particles, fine mode, during the printing process in the printing office air.

Today in Iran, air pollution is the first issue of environmental pollution and urban tra  ortation system is the one of the main causes its release, Aerosols and gases are the most important known pollutants in the air. Air pollution has many reasons in different cities of Iran such as increase traffic, deforestation, forest fires, increased establishment of factories and power plant, natural factors such as dust storms. Pollution of geo graphical environments in Iran by Aerosols and gases is one of the most important issues in this country. Air pollution has 2 type of pollutant: a) Particle   b) Gas , particularly   there are Jobs and various industrial activities that produce this pollutants. Therefore, measurement of this pollutants is very important because they are effective on health and environmental degradation, Therefore, we must use efficient methods for reduce the concentration this pollutants.In this study, after a brief review of air pollution;, in summary, we defined air pollution, then, we   measured Aerosol   with Cascade Impactor 8 stages and i   the next step, we analyzed   the physical and chemical data in different places of Kermanshah city. In determining the chemical composition, results show that among the five elements V, Cr, Hg, Cd and pb, Hg has the highest mass. In determining the Aerosol size distribution, results show that in Dust storm and Urban traffic the most particles are in the range of Coarse Mode and Accumulation Mode. In the next section, we defined concentration of gaseous pollutants in different places of Kermanshah city , results show that printer home produces O3 and NO2 and heavy traffic produces CO,CH4,Ben and NOx. At the end, the ways have been suggested for reduction of air pollution.

    nteractions of baryons containing two heavy quarks spectroscopy and light quark and a heavy quark mass approaches infinity, so that will be very simple, and that is because of heavy quarks, heavy diquark smaller than a length scale of this allowed us to have strong interactions that the color of the perturbation theory of quantum mechanics to calculate the fragmentation functions of these heavy baryons .in oneering heavy fragmentation functions include quarks b nd c baryons in the quark  - diquark model

Based on the laws of 0in 0in 10pt" >Such spatial periodic structures are of two types: ‎ The first type is the macro undulator in a vacuum‎, ‎such as linear magnetic undulator‎. ‎The second one is called crystalline micro undulator (nano micro undulator)‎. ‎The theory of electromagnetic radiation produced by relativistic charged particles moving in nano structures, such as in Carbon nano-tubes is one of the newest areas of the Radiation Physics.   In this Master thesis, ‎the dynamic of motion of relativistic charged particles moving in nano crystalline structures, such as Carbon nano-tubes and produced electromagnetic radiation ‎will be considered. The periodic structure of the Carbon nano tubes will be considered in brief as a device for radiation production. ‎Then‎, ‎according to the periodic structure of the Carbon nanotubes‎, ‎the approximate inter atomic potential taking n into account the thermal vibrations of atoms will be calculated‎. ‎The dynamic of channeling motion will be studied in classical and quantum approximation.   ‎At the end‎, some features of the spectrum of produced radiation will be discussed‎.

     Reflection and refraction of electromagnetic (EM) signals at both horizontal and vertical interfaces separate media of different electrical parameters EM methods have been developed and employed to recognize the geological features and particularly fault zones in many regions. To achieve higher lateral resolution and also greater penetration depth, the magnetotelluric (MT) method is one of the most effective electromagnetic techniques to create image of the subsurface structures electrically. Due to the contrast of resistivity in different layers of the earth and subsurface structures, such as fault and base rock, we can investigate the structures via MT method.   In 2016 a wide frequency range of magnetotelluric measurements were carried out at the north east of   Kermanshah province to understand the crustal electrical conductivity of the region by putting emphasis on locating the Geological structures. Magnetotelluric profile has been passed in Mianrahan which is situated in different geological structures based on recognizing the base rock as well as the faults.     The electric and magnetic field components were acquired along a profile at 6 stations with 2000m distance.A robust single site processing followed by the inversion. One dimensional and two dimensional modeling were performed .Then the inversion results revealed electrical conductivity structures in correlation with geological features. Two dimensional model has demonstrated a fault structure and resolved layers with sharp resistivity contrasts. The basement was also detected by the two dimensional model at about 9000m depth with 520 ohm.m resistivity.

پس از آزمايش ناكشسان عميق الكترون پروتون SLAC] در سال 1969 تلاش هاي زيادي توسط دانشمندان نظري و تجربي براي بدست آوردن اطلاعات بيشتر در مورد ساختار پارتون­ها [2]   يعني كوارك­هاي ظرفيت، كوارك­هاي دريا و گلئون­ها مربوط به هادرون­  hy;ها و هسته انجام شده است. در بخش تجربي اولين مشاهده در سال 1983 توسط گروه EMC[3] بود. آنها مشاهده كردند كه هنگامي كه هدف از دوتريم به هسته­ي ­سنگين تغيير داده شود اثر قابل توجهي در توابع ساختار نوكلئون­ها ظاهر مي­شود. اما در سال ­هاي اخير بسياري از آزمايش­ها مطالعه­ي خود را روي توابع ساختار هادرون­ها (عمدتا پروتون ونوترون) در xهاي(xمتغير مقياس بيوركن است[4] (كوچك متمركز كرده­اند كه در آنجا كوارك­هاي دريا و گلئون­ها نقش مهمي را بازي مي­كنند. در سال­هاي اخير هم, استفاده از هدف­هاي هليوم سه و تريتيوم غيرقطبيده براي پرتوهاي با انرژي GeV 11 آزمايشگاه جفرسون فراهم شده است . به منظور محاسبه تابع ساختار نوترون از نسبت تابع ساختار هليوم سه و تريتيوم استفاده مي­شود چون، برخلاف پروتون تابع ساختار نوترون را نمي­توان به صورت مستقيم مورد مطالعه قرار داد، بنابراين بايد تابع ساختار آنرا به شيوه­ي غير مستقيم استخراج كنيم. در سال 1986جفي و هدبوي[5] با استفاده از پراكندگي ناكشسان ژرف نسبت تابع ساختار پروتون يا نوترون را در حالت مقيد و آزاد را محاسبه كردند اين انتظار وجود داشت كه، نسبت تابع ساختار حالت مقيد به حالت آزاد برابر يك باشد اما با مشاهده نتايج تجربي و نتايج تئوري و مقايسه آنها ديده شد كه اين نسبت يك نيست. بنابراين به دنبال توجيه اين اختلاف با ارائه مدل­ها و روش­هاي نظري بودند. دلايل مختلفي براي اين تغيير توزيع كواركي داخل نوكلئون­هاي مقيد و آزاد بيان شد كه از جمله مي­توان به اثر فرمي، اثر انرژي بستگي و اثر تبادل كواركي اشاره كرد. در اين پايان نامه بر آن هستيم تا با استفاده از مدل كوارك سازنده سهم كوارك­هاي دريا و گلئون­ها را در توابع ساختار نوكلئون­ها اعمال نموده و انتظار مي­رود كه نتايج اين محاسبات با داده­هاي تجربي به ويژه با داده­هايي كه از آزمايشگاه سرن و جفرسون كه در سال­هاي اخير بدست آمده­اند هم­خواني بهتري داشته باشند.     

در اين پايان نامه پس از مقدمه ي مختصر بر پراكندگي هاي كشسان و ناكشسان رابطه اي براي سطح مقطع ديفرانسيلي پراكندگي ناكشسان الكترون پروتون بدست مي آيد وسپس مدل پارتون و رابطه ي اصلي اين مدل يعني رابطه ي كالان گراس بدست مي آيد اين رابطه به ما اجازه مي دهد كه ر صورت داشتن توابع توزيع پارتون هاي درون نوكلئون بتوان به توابع ساختار آنها دست يافت .

In decays of the Z0, the dominant mechanism for the direct production of charmonium states is the decays of the Z0 into a pair heavy   anti quark b or c followed by its fragmentation into the charmoniom and butmoniom states. First we calculate the fragmentation functions describing the splitting of   heavy anti quarks into S-wave quarkonium states to leading order in the QCD coupling costant. We use our   fragmentation functions to calculate the production rate of heavy quarkonium states in Z0 decay and   so decay rate of Z0 to the pair heavy quark   cc ,bb.       PACS No.13

This thesis describes azimuthal dependence of heavy quark initiated contributions to the lepton-nucleon deep inelastic scattering (DIS). In general, in recent decades, investigation of heavy quark production is of particular interest and the activities that accomplished in different collaborations express significance of this matter. In this work, since the sources of the production of heavy quark is different relative to the kind of colliding particles, we propose different reactions leading to the production of heavy quarks and finally limit our study to production of heavy quark in lepton-nucleon DIS. For this reason, first we investigate deep inelastic electron-proton scattering and define the cross section of this process, then we write the relations between parton-level semi-inclusive structure functions and the helicity   cross sections in terms of arbitrary values of heavy quark mass. Then the azimuth-dependant   lepton-quark DIS in helicity basis has been calculated. Finally, we investigate the numerical properties of   and   distributions caused by photon-quark scattering (QS) contribution. We conclude that contrary to the photon-gluon fusion (GF) component, the QS mechanism practically is -independant. This fact implies that measuring azimuthal distributions in these processes directly can probe the heavy quark inside the proton. Our results indicate that the GF and QS predictions for   asymmetries are quantitatively well defined in fixed flavor number scheme (FFNS): they are stable, both parametrically and perterbatively.   

  در اين پايان­نامه ما در ابتدا به معرفي پروژه برخورددهنده بزرگ هادرون-الكتروني پرداخته و سپس با معرفي مدل استاندارد فيزيك ذرات و جدول ذرات بنيادي، در مورد اهميت و خواص و نيز نحوه توليد كوارك سر به عنوان سنگين­ترين ذره بنيادي شناخته شده در طبيعت با استفاده از نتايج آزمايشگاهي صحبت خواهيم كرد. در محاسبات نظري، كوارك سر به دليل جفت شدگي بسيار زيادي كه با بوزون هيگز دارد مورد بسيار خوبي جهت تحقيق در حيطه فيزيك هيگز مي­باشد. به همين دليل در اين كار ما به جستجو و تعيين سطح مقطع براي جفت شدگي كوارك-پادكوارك سر و بوزن هيگز در فرآيند پراكندگي ناكشسان عميق الكترون-پروتون در برخورددهنده بزرگ هادرون-الكتروني پرداختيم. فرآيند مورد نظر ما كه از پراكندگي ناكشسان عميق بين الكترون و پروتون سر چشمه مي­گيرد، به وسيله فوتون مجازي منتشر شده از الكترون و نيز گلوئون ساتع شده از پروتون انجام مي­شود كه به اين فرآيند همجوشي بوزون-گلوئون مي­گوييم. نتيجه محاسبات ما با استفاده از پتانسيل عظيم به وجود آمده در برخورددهنده بزرگ هادرون-الكتروني مي­باشد به اين دليل كه برخورددهنده­هاي لپتون-هادروني نسل قبل انرژي لازم براي توليد اين ذره سنگين را نداشتند. در نهايت ما نتيجه بدست آمده از سطح مقطع مربوط به جفت­شدگي كوارك-پادكوارك سر و هيگز را با نتايج موجود در برخوردهاي هادرون-هادروني و همجوشي گلوئون-گلوئون مقايسه كرده و بيان مي­كنيم كه هرچند سطح مقطع اين فرآيند از طريق همجوشي بوزون-گلوئون كمتر است اما دقت محاسبات براي شناخت فيزيك هيگز بسيار دقيق­تر خواهد بود.

In this thesis first we are talking about Deep inelastic scattering and Parton model. In short study nuclear model and effect to change parton distribution in nuclei. Then we come to the parton distribution evolution equations, DGLAP, and how to solve it. Here we solve the equation in the approximation DLL. Finally, with the help of a weight factor obtain nuclear Parton distribution functions from a single nucleon Parton distribution functions (related to experimental measurements).Result of study nuclear distribution function show the nuclear effect such as: Shadowing in low x and EMC and anti Shadowing in high x.