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Chinese Physics C 2008年第11期32卷 877-881页

作者： farshid tabbakh azim ahmadinyar School of Nuclear Science Institute of Nuclear Reactors and Accelerators Atomic Energy Organization of Iran North Kargar Av. Tehran Iran

In this paper we study the analytical and statistical results of estimating the gamma dose rate at pool access floor in TRR when the core shield accidentally decreases to some non-permitted levels. Due to the risk of experimental techniques, we use the analytical and statistical methods. In normal conditions （no risk）, the discrepancies between experiment and two methods are justified and it is found that for such problems we have to normalize these methods to experimental results as follows： the analytical method by factor 0.13 and MCNP by 1.7.

关键词： TRR gamma-ray dose rate MCNP4C

Effects of cooling channel blockage on fuel plate temperature in Tehran Research Reactor

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Nuclear Science and Techniques 2009年第3期20卷 184-187页

作者： tabbakh farshid School of Nuclear Science Institute of Nuclear Reactors and Accelerators Atomic Energy Organization of Iran Tehran Iran

In this study, the variation of the temperature distribution of the fuel plate in Tehran Research Reactor core was studied in case of coolant channels blockage. While the experimental method is not possible, both the analytical and simulation methods were used to obtain the more reliable data. The results show that one channel blockage will increase the fuel temperature to about 100%, but it does not lead to clad melt down still. With further calculation and simulation it is understood that if the coolant velocity drops to 90% of its nominal value, it may causes the clad melting down. At least two channels with complete blockage even at the positions far from the core center can also melt down the clad.

关键词：反应堆核技术研究实验方法

Precise study of the first deflecting magnet of “Rhodotron” (TT200) using transfer matrices and ANSYS11

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Chinese Physics C 2009年第10期33卷 897-900页

作者： farshid tabbakh Institute of Nuclear Science and Technology School of Irradiation ApplicationAtomic Energy Organization of Iran

The beam trajectory in the first deflecting magnet of ＂Rhodotron＂ TT200 has been analyzed precisely by both optical and simulation methods. We found discrepancies between these two methods at the order of （10-3） for the slit distance and deflecting radius and at the order of （10-4） for the magnetic flux density. The main goal of the paper is beam focusing, considering the angular and momentum dispersion of the particles for the magnet designed by ANSYS.

关键词： Rhodotron deflecting magnets magnetic sector field ANSYS11

Target optimization for a 10-MeV E-beam neutron converter

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Nuclear Science and Techniques 2010年第2期21卷 69-71页

作者： tabbakh farshid KHALAFI Hossein Institute of Nuclear Science and Technology Irradiation and Application Research School Atomic Energy Organization of Iran Tehran Iran Institute of Nuclear Science and Technology Atomic Energy Organization of Iran Tehran *** Iran

Accelerator-based target design and optimization is an approach for neutron generation. The target plays an important role for a neutron source on an electron accelerator. For optimizing a neutron source using 10 MeV electron beams of Rhodotron-TT200, Pb, Ta, or W alloys with Be were calculated as photo-neutron converter. The neutron yield, flux and energy were simulated using the MCNPX code. The results indicate that a 10 MeV electron beam is capable of producing high-intensity neutron flux of 1013n·cm–2·s–1 with average energy of 0.8 MeV.

关键词：优化目标电子束中子源电子加速器中子通量平均能量生成方法中子产额

Radiation emission from the 'Rhodotron-TT200' cavity

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Chinese Physics C 2011年第7期35卷 675-678页

作者： farshid tabbakh Mahmud Borhani Institute of Nuclear Science and Technology Nuclear Reactors and Accelerators Research School North Kargar Av. Tehran Iran P.O. Box *** Science Faculty Yazd University

In this paper, the X-rays emitted from the Rhodotron-TT200 cavity have been studied in depth. We found that the Bremsstrahlung interaction is the only contribution of X-ray generation important to safety. The X-ray dose rate in the Rhodotron vault is calculated for normal conditions based on MCNP4C results. The presented calculation shows good agreement with the experimental measurements, which consequently confirms the reliability of the calculation for use in shielding design and other safety aspects.

关键词： electron beam rhodotron beam loss X-ray dose rate MCNP code

Precise correction to parameter ρ in the littlest Higgs model

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Chinese Physics C 2008年第2期32卷 100-103页

作者： farshid tabbakh F. Farnoudi School of Nuclear Science Institute of Nuclear Science and Technology Atomic Energy Organization of Iran Northern Kargar Av. Tehran Iran

In this paper tree-level violation of weak isospin parameter, ρ in the frame of the littlest Higgs model is studied. The potentially large deviation from the standard model prediction for the ρ in terms of the littlest Higgs model parameters is calculated. The maximum value for ρ for f =1 TeV, c = 0.05, c＇ = 0.05 and v＇ = 1.5 GeV is ρ = 1.2973 which means a large enhancement than the SM.

关键词： the littlest Higgs model custodial symmetry violation

Muon g - 2 in the Littlest Higgs Model

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Communications in Theoretical Physics 2006年第5期45卷 894-900页

作者： farshid tabbakh LIU Jing-Jing MA Wen-Gan Department of Modern Physics University of Science and Technology of China （USTC） Hefei 230027 China

In this paper the anomalous magnetic dipole moment ofmuon in the littlest Higgs （LH） model is studied at one-loop level. We discuss the dependence of the contributions on the global symmetry breaking scale f, mizing angles c` and , and the Higgs triplet vacuum expectation value v＇ in the electroweak precision data preferring ranges. We find that the LH model can give a relatively small, but non-negligible extra weak contribution to the muon anomalous magnetic moment and can reduce the deviation of △aμ from 2.6σ for the SM to 2.5σ for the LH model.

关键词： Littlest Higgs model anomalous magnetic dipole moment of muon

Top Quark Flavor Changing Decay t→ cH^0 in Little Higgs Model

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Communications in Theoretical Physics 2005年第4X期44卷 651-658页

作者： farshid tabbakh LIU Jing-Jing MA Wen-Gan ZHANG Ren-You HOU Hong-Sheng Department of Modern Physics University of Science and Technology of China Hefei 230027 China

We study theoretically the quantum effects of the littlest Higgs model (LH) mediated by flavor changing one-loop Feynman diagrams on the rare decay process t → cH0. The comparison of the decay width in the LH model with that in the standard model (SM) is made. We find that the decay branch ratio of t → cH0 in the LH model is at most of the order ～ 10-12, which is two order larger than in the SM. The numerical results show that the difference between the branch ratios in the LH model and the SM is generally sensitive to the LH model parameters, such as symmetry breaking scale f, Higgs boson mass mH0, and x = v'4f /v2 in our chosen parameter space, but relatively insensitive to the value choice of the cosine of the mixing angle c and the ratio λ1/λ2.

关键词： littlest Higgs model top quark rare decay flavor changing neutral current

Photonuclear Effect on ITER Operation

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Journal of Applied Mathematics and Physics 2015年第8期3卷 1227-1230页

作者： farshid tabbakh Amir Hossein Gharashi Plasma and Nuclear Fusion Nuclear Science and Technology Tehran Iran

In this study, neutron and gamma radiation produced during the ITER tokamak operation including the nuclear heating were studied. This is an approach for analyzing the neutron flux by their contributions. The calculations were conducted using Geant4 Monte Carlo method based on the ITER simplified geometry. It was found that for present design of ITER, only 0.1% of neutrons is contributed by photonuclear interaction while, 33% belongs to the (n, xn) reaction. Finally by adding Beryllium element in the coolant leading to the increase in the neutron flux by increasing the rate of (γ, n) reactions was calculated.

关键词： ITER Photo-Nuclear Wall-Loading Energy Deposition GEANT4

A Vicenary Analysis of SARS-CoV-2 Genomes

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Computers, Materials & Continua 2021年第12期69卷 3477-3493页

作者： Sk Sarif Hassan Ranjeet Kumar Rout Kshira Sagar Sahoo Nz Jhanjhi Saiyed Umer Thamer A.tabbakh Zahrah A.Almusaylim Department of Mathematics Pingla Thana MahavidyalayaPaschim Medinipur721140India Computer Science&Engineering National Institute of Technology SrinagarHazratbal190006J&KIndia Department of Computer Science and Engineering SRM UniversityAmaravatiAP522502India School of Computer Science and Engineering Taylor’s UniversitySubang Jaya47500Malaysia Department of Computer Science and Engineering Aliah UniversityKolkataIndia Materials Science Research Institute King Addulaziz City for Science and Technology(KACST)Riyad6086Kingdom of Saudi Arabia General Administration of Research and Development Laboratories King Abdulaziz City for Science and Technology(KACST)Riyad6086Kingdom of Saudi Arabia

Coronaviruses are responsible for various diseases ranging from the common cold to severe infections like the Middle East syndromes and the severe acute respiratory ***,a new coronavirus strain known as COVID-19 developed into a pandemic resulting in an ongoing global public health ***,there is a need to understand the genomic transformations that occur within this family of viruses in order to limit disease spread and develop new therapeutic *** nucleotide sequences of SARS-CoV-2 are consist of several *** bases can be classified into purines and pyrimidines according to their chemical *** include adenine(A)and guanine(G),while pyrimidines include cytosine(C)and tyrosine(T).There is a need to understand the spatial distribution of these bases on the nucleotide sequence to facilitate the development of antivirals(including neutralizing antibodies)and epitomes necessary for vaccine *** study aimed to evaluate all the purine and pyrimidine associations within the SARS-CoV-2 genome sequence by measuring mathematical parameters including;Shannon entropy,Hurst exponent,and the nucleotide guanine-cytosine *** Shannon entropy is used to identify closely associated *** Hurst exponent is used to identifying the auto-correlation of purine-pyrimidine bases even if their organization *** frequency patterns can be used to determine the distribution of all four proteins and the density of each *** GC-content is used to understand the stability of the *** relevant genome sequences were extracted from the National Center for Biotechnology Information(NCBI)virus ***,the phylogenetic properties of the COVID-19 virus were characterized to compare the closeness of the COVID-19 virus with other coronaviruses by evaluating the purine and pyrimidine distribution.

关键词： Fractal dimension shannon entropy hurst exponent GCcontent SARS-CoV-2