A review of synchrotron X-ray radiation spectroscopy and imaging ‎ ‎ Abolfazl Keshtkar vanashi دانشگاه بین المللی امام خمینی (ره) author Hossein Ghasemzadeh mohammadi دانشگاه بین المللی امام خمینی (ره) author Shiravan Afraz دانشگاه بین المللی امام خمینی (ره) author Saeid Asghari zadeh دانشگاه تبریز author Mohammad Lamei rashti سازمان انرژی اتمی ایران author Mona Haddad دانشگاه بین المللی امام خمینی (ره) author text article 2021 per Synchrotron radiation is an advanced polarized and collimated light source with high brilliance and intensity. whereas This radiation has a wavelength range of infrared to the highest-energy x-rays. In this article, we provide a summary of application of x-ray spectroscopy with synchrotron radiation to x-ray spectroscopy. Here we discuss ten types of x-ray techniques include X-ray Powder Diffraction(XRPD), Wide Angle X-ray Scattering (WAXS), Small-Angle X-ray Scattering (SAXS), X-ray fluorescence(XRF), X-ray reflectometry (XRR), Near Edge X-ray Absorption Fine Structure (NEXAFS), X-ray Absorption Near Edge Structure (XANES), Photo Electron Spectroscopy (XPS), X-ray Emission Spectroscopy (XES), and x-ray imaging spectroscopy. These techniques have good potential for characterization of various micro- and nano-materials. Furthermore, some advantages of the use of these techniques are as follows: improving signal to noise ratio, better spatial resolution, and improving data acquisition. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 1 22 https://ijpr.iut.ac.ir/article_1669_1b0c94853a458d856a33d821ae17b394.pdf dx.doi.org/10.47176/ijpr.21.1.39511 ‎ Quantum dynamics of a f-deformed cavity-field beyond the rotating wave approximation M Daeimohammad Department of Physics, Najafabad Branch, Islamic Azad University, Najafabad, Iran author text article 2021 per The aim of this study is to investigate dynamical properties of a two-mode f-deformed cavity- field ‎coupled to an effective two-level atom with and without the rotating wave approximation. The first ‎section discusses the theoretical model of the interaction between a two-mode cavity-field and an ‎effective two-level atom within the framework of an f-DJCM without the rotating wave ‎approximation. After that, we obtain the reduced density matrix of the cavity-field with and without ‎the rotating-wave approximation. Then, we have investigated the effect of the counter-rotating ‎terms on temporal evolution of various non-classical properties of the cavity-field, i.e., photon-‎counting statistics, the cross correlation between the modes of the field, and the quantum ‎fluctuations of the quadrature components. Particularly, we compare the numerical result for three ‎different values of the deformation parameter q (q=1, q=1.1, q=0.9) with and without applying the rotating ‎wave approximation. By using of the numerical method, we concluded that even under the ‎condition in which the RWA is considered to be valid, there are the significant effects of virtual-‎photon field on the photon-counting statistics, the cross correlation between the modes of the ‎field, and the quantum fluctuations of the quadrature components‎. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 23 39 https://ijpr.iut.ac.ir/article_1670_714b3e86e1781bafb1647e3713a3d5a4.pdf dx.doi.org/10.47176/ijpr.21.1.81109 Tuning of ionic transport through graphene oxide fibers by sheets size ‎ H Ghanbari Physics Department, Sharif University of Technology, Tehran, Iran ‎ author A Esfandiar Physics Department, Sharif University of Technology, Tehran, Iran ‎ author M Khansanami Physics Department, Sharif University of Technology, Tehran, Iran ‎ author text article 2021 per In this study, graphene oxide fibers are introduced as new graphene oxide (GO) membranes with the ‎capability of ion selectivity‏.‏‎ Graphene oxide fibers, like other macro structured membranes, are always ‎associated with cavities and defects. To solve this problem, a 50% combination of graphene oxide ‎suspension including small sheets with an average size of ~ 0.5 µm2 and large sheets with an area of more ‎than 10 µm2 was used. According to the morphological results of scanning electron microscopy, as well as ‎the amount of ionic transport through the fiber, reduction of cavities and its defects were confirmed. ‎Moreover, it was found that ionic current through fibers consist of large and small GO sheets is more ‎controllable. This leads to more ionic selectivity via tunable swelling. Finally, the scalability of graphene ‎oxide fibers investigated and found that increasing number and length of the fibers increases the ionic ‎current as linear trend‎. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 41 49 https://ijpr.iut.ac.ir/article_1671_51eef0294d523b18678e12b5f575c9a5.pdf dx.doi.org/10.47176/ijpr.21.1.61071 Dissipative motion of Gaussian ‎wavepackets: free propagation and ‎transmission through a rectangular ‎barrier M Bakhtiyarian Department of Physics, Faculty of Sciences, University of Qom, Qom ‎ author V Mousavi Department of Physics, Faculty of Sciences, University of Qom, Qom ‎ author text article 2021 per Ignoring thermal fluctuations of the environment, taking into account only its dissipative effects, free propagation of a Gaussian wavepacket is studied in the framework of the linear Caldirola-Kanai (CK) equation and non-linear equations, the Schrodinger-Langevin (SL) equation, known as Kostin equation, and the Schuch-Chung-Hartmann (SCH) equation. By a Gaussian ansatz for the probability density one obtains two equations, one for the evolution of the center of the wave packet which is just the classical Langeving equation and one for the evolution of the width of the wavepacket. This last equation has different forms in different approaches having only an analytic solution in the CK and SCH frameworks. Computations show that for a given friction, the width of the wavepacket increases with time in all approaches. In a given time, it reduces with friction in both CK and SL approaches revealing localization effects of dissipation, while has opposite behavior in the SCH approach. Furthermore, energy expectation value and its time-derivative is computed and compared in all approaches. It is shown that the rate of energy is given by the expectation value of momentum field in the SL framework. Finally, transmission of a Gaussian wavepacket from a rectangular barrier is numerically studied in the context of CK and compared to the non-dissipative case. The transmission decreases considerably with the dissipation.   Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 51 61 https://ijpr.iut.ac.ir/article_1672_a5f0f01c63dc6162a2666423f523c5e7.pdf dx.doi.org/10.47176/ijpr.21.1.24022 The study of optical bistabiltiy in a hydrodynamic metallic nanoparticle N Daneshfar Department of Physics, Faculty of Sciences, Razi University, Kermanshah, Iran‎ author Z Noormohammadi Department of Physics, Faculty of Science, Razi University, Kermanshah, Iran author text article 2021 per In this paper, the optical bistability in a plasmonic nanoparticle by using the Hydrodynamic model for conduction electrons is investigated. It is shown that the optical bistable threshold, the bistable region and the shape of hysteresis loop are dependent on the permittivity of the surrounding medium, and the composition of plasmonic nanoparticle. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 63 67 https://ijpr.iut.ac.ir/article_1673_95558b1ea6b464e7a81f26ae37b1592a.pdf dx.doi.org/10.47176/ijpr.21.1.71098 Dissipative diffraction in time and early-arrival in continuous quantum-classical ‎transition S. V. Mousavi Department of Physics, Faculty of Sciences, University of Qom, Qom, Iran author text article 2021 per Diffraction in time and early-arrival phenomena will be studied in the context of dissipative systems. This theoretical consideration is done by using the linear scaled wave equation proposed in the framework of Caldirola-Kanai theory for the continuous quantum-classical transition. Two simple but physically important and interesting examples are studied, sudden release from a shutter where transient behaviors (diffraction in time) are seen; and also transmission through a time-dependent parabolic barrier where early-arrival is seen. Calculations show that diffraction in time is a non-classical effect and temporary behaviors are gradually suppressed as the friction increases. Furthermore, early-arrival is seen even in the classical regime. This means that early-arrival is not a non-classical phenomenon. This behavior will be explained by means of scaled trajectories which are just Bohmian trajectories in the quantum regime. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 69 79 https://ijpr.iut.ac.ir/article_1674_b7d0439b650d5f8e2009fcc3432632a0.pdf dx.doi.org/10.47176/ijpr.21.1.21502 Edge mode dynamics in long-range Kitaev model Saeid Ansari Department of Engineering Sciences and Physics, Buein Zahra Technical University, Buein Zahra, Iran author Rohollah Jafari Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan, Iran author text article 2021 per In this paper we study the dynamics of long-range pairing and hopping p-wave superconducting chain after a ‎sudden quench of chemical potential. We have shown that the quantum-classical phase transition occurs ‎when the system is quenched to the critical point and the Loschmidt echo shows perfect periodic oscillations. ‎Moreover we have studied the dynamical phase transition for a quench across the critical point. Our analysis ‎shows that the dynamical phase transition occurs for the cases where the system initially prepared in the ‎massless edge modes. While the system does not show dynamical phase transition when the system is ‎prepared in the massive edge modes, even the quench crossing the critical point‎‎. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 81 90 https://ijpr.iut.ac.ir/article_1675_89721b7eb48bb8136eb5bd80a7a573a2.pdf dx.doi.org/10.47176/ijpr.21.1.11155 Presenting a relatively simpler method than the tensor method for calculating the diagonal generators of higher representations of Lie groups to calculate the quark ‎potentials in the thick centervortex model‎ H Lookzadeh Faculty of Physics, Yazd University, Yazd, Iran author M Hossieni Faculty of Physics, Yazd University, Yazd, Iran author text article 2021 per One of the successful models in describing the quark phenomenon is the thick center vortex model. In this model, confinement is attributed to the group's non-trivial centers. The non-trivial centers of the gauge group are also the reason of the presence of vortices. Vortices are point-like soliton structures in two dimensions and line like in three dimensions. In this model we need the diagonal generators of the group representations to calculate and plot a quark potential diagram in different representation. It is common to use the tensor method to calculate these diagonal generators, which requires a lot of calculations. In this paper after introducing the thick center vortex model the tensor method is introduced. Then the concept of root and weight diagram in Lie groups is introduced. Using the root and weight diagram an efficient and simple method for calculating the diagonal generators of group representations is presented. The groups studied in this article are SU (2) and SU (3), which can be extended to other groups. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 91 98 https://ijpr.iut.ac.ir/article_1676_bb67787960e92889f3da81e19f301d59.pdf dx.doi.org/10.47176/ijpr.21.1.91119 Theoretical study of ThO2 by first principles calculations M Mahdavi Department of Physics, Faculty of Science, University of Mazandaran, Babolsar, Iran author M H Sahafi Department of Physics, Faculty of Science, University of Mazandaran, Babolsar, Iran author text article 2021 per In this paper, the thermodynamic, structural properties and vibrational spectrum of thorium dioxide have been studied using the Density Functional Perturbation Theory (DFPT) and Density Functional Theory (DFT) in the framework of first principles calculations. Quantum espresso software, which is an open source computing code, has been used in order to compute the kohn-Sham equations to obtain the minimum total energy of crystal. The vibrational spectrum of the thorium dioxide was examined along various symmetrical directions, and the results showed the dynamical stability of the crystal system. The quasi-harmonic Debye-Einstein model as implemented in GIBBS2 Code was used to calculate the thermodynamic properties of thorium dioxide at high temperatures and pressures. The simulation results showed that the Debye temperature of thorium dioxide decreased with increasing temperature at a constant pressure and increased with increasing pressure at a constant temperature. Increasing the Debye temperature indicated an increase in the crystal stiffness and the average sound velocity. It was observed that the volumetric thermal expansion coefficient and gruneisen parameter decreased exponentially with increasing pressure at a constant temperature, while increased with increasing temperature at a constant pressure, indicating an increase in heat transfer in the crystal lattice Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 91 109 https://ijpr.iut.ac.ir/article_1677_e7e59b65a2ab3d1449ebdfdde7301b80.pdf dx.doi.org/10.47176/ijpr.21.1.41038 Fabrication of hydrophilic and hydrophobic silica aerogel by drying‎ at ambient pressure and their structural properties M Zargar Shoushtari Department of Physics, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran author N Navazesh Department of Physics, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran author text article 2021 per In this research, silica aerogel was made by sol-gel method with sodium silicate precursor ‎and drying at ambient temperature. The silica aerogel prepared by this method is ‎superhydrophobic. To make it hydrophilic, the sample was heated at 400 °C for 2 h. The ‎structure of the samples was studied using X-ray diffraction, scanning electron microscopy, ‎adsorption and desorption of nitrogen gas. To investigate the hydrophilicity and ‎hydrophobicity of the samples, the water droplet contact surface test was performed. The ‎chemical bonds of the prepared samples were studied using Fourier transform infrared ‎spectroscopy. The overall results showed that the size of the particles and the pores increase ‎and become smaller, respectively when the hydrophilicity of the silica aerogel sample ‎changes to the hydrophobic sample. The angle of contact of the water droplet with the ‎surface of the hydrophobic sample is 170°, while reaches to 51° for the hydrophilic sample‎. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 111 119 https://ijpr.iut.ac.ir/article_1678_7d109ec544e0fb6472ff86ec8000f198.pdf dx.doi.org/10.47176/ijpr.21.1.61067 Synthesis and optical properties investigation of TiO2 ‎nanotubes for use in polymer gel-state dye sensitized solar cells Z Seidalilir . Department of Physics, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran‎ Center for Research on Laser and Plasma, Shahid Chamran University of Ahvaz, Ahvaz, Iran‎ author R Malekfar Department of Physics, Faculty of Science, Tarbiat Modares University, ‎Tehran, Iran author text article 2021 per In this paper highly ordered TiO2 nanotube (TNT) arrays were synthesized using potentiostatic anodization of Ti foil for 12 h at voltage of 60 V and used in polymer gel-state dye senisitized solar cells (DSSCs) . To investigate the morphology and optical properties of the TNTs, scanning electron microscopy (SEM), Raman spectroscopy and X-ray diffraction techniques (XRD) have been used. The average diameter and length of the TNTs were 100 nm and 30 µm, respectively. XRD and Raman measurements indicated the pure anatase phase of TNTs. A polymer poly(methyl metacrylate- co-methacrylic acid) (PMMA-MA) was mixed with a 3-methoxypropionitrile (MPN) based liquid electrolyte to prepare a gel-state polymer electrolyte. The prepared electrolytes containing varied concentrations of PMMA-MA were characterized by electrochemical impedance spectroscopy (EIS). Power conversion efficiency of NT based DSSCs using a polymer gel electrolyte containing PMMA-MA was comparable with that of the corresponding liquid counterpart. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 121 130 https://ijpr.iut.ac.ir/article_1679_36958f06e2448876e3aa5e6f8d9feb6c.pdf dx.doi.org/10.47176/ijpr.21.1.71087 Effect of the frequency detuning on the stability analysis in a ‎semiconductor laser subject to optical injection: Hopf and Routh-Horwitz ‎conditions Kh Mabhouti ‎ Physics Department, Faculty of Sciences, Urmia University, Urmia, Iran author N Samadzadeh ‎ Physics Department, Faculty of Sciences, Urmia University, Urmia, Iran author text article 2021 per In this paper, the rate equations for a laser diode subject to an optical injection are studied both ‎analytically and numerically. By determining the Hopf and Routh- Hurwitz conditions, the stability ‎boundaries of the laser system have been studied. The stability diagrams have been discussed in terms ‎of detuning and the injection rate for different values of the linewidth enhancement factor.‎‏ ‏Also, we ‎obtain critical relations for the Hopf points that lead to instability in the laser system. It has also ‎shown that obtained relations depend on four parameters: detuning, linewidth enhancement factor, ‎optical injection strength and pumping current‎. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 131 143 https://ijpr.iut.ac.ir/article_1680_3191e128d2f0c3faaa1a9c9e61c6ee07.pdf dx.doi.org/10.47176/ijpr.21.1.39861 CP and Bell's inequality violation in the neutrino-antineutrino oscillations S M Saberi Fathi Department of‎ Physics, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran‎ author N Imani Department of‎ Physics, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran‎ author text article 2021 per Bell's inequality has made the ability to find nonlocality in what happened by a numerical indicator. CP violation is one of the most important phenomena that occur in nature. It represents asymmetry in the matter and anti-matter in the universe. In this paper, we use a thought experiment to obtain a formalism of Bell's inequality of type CHSH for Majorana neutrino. This inequality is sensible to CP violation. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 145 159 https://ijpr.iut.ac.ir/article_1681_2a3a52a74bcc35ad7b8dfbe1e5e839ca.pdf dx.doi.org/10.47176/ijpr.21.1.31032 Investigation of nonlinear optical properties of Eosin-B nanoparticles painted ‎ N Karshenas Department of Physics, University of Sistan and Baluchestan, Sistan and Baluchestan, Iran author S Sharifi ‎Department of Physics,‎ Ferdowsi University of Mashhad, Mashhad, Iran ‎ author H Ghanadan ‎Department of Physics,‎ Ferdowsi University of Mashhad, Mashhad, Iran ‎ author N Hatefi Kargan Department of Physics, University of Sistan and Baluchestan, Sistan and Baluchestan, Iran author text article 2021 per In this study the nonlinear optical properties of Eosin-B dye nanoparticles were studied using the ‎scanning-fluorescence spectrophotometer and fluorometer method. The nano water droplet in the ‎oil medium is prepared by a combination of hexane and surfactant water, which is painted inside ‎the drop by Eosin-B. The droplet size was studied on a nonlinear refractive index using a 532 nm ‎laser with a scanning power of 80 mW. The results show that the surface effects on the nano-‎droplets cause the droplets to have a larger nonlinear refractive index. This change was due to a ‎decrease in the accumulation of dyes inside the droplet as well as a decrease in the polarity of the ‎drop solvent relative to the water solvent. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 161 169 https://ijpr.iut.ac.ir/article_1682_51f2f31080fb3b9e2a34baebccc4903e.pdf dx.doi.org/10.47176/ijpr.21.1.41034 A four-level atom enclosed in an optical cavity with multiphoton transition in the‏‏‎ ‎steady-state regime B Parvin Department of Physics, Faculty of Basic Sciences, University of Maragheh, ‎Maragheh, Iran author text article 2021 per The mechanism of a four-level atom confined in a single-mode optical cavity with multiphoton transition is theoretically investigated in the steady-state. The behavior of the atom-cavity system is delineated by the master equation which in order to solve this equation, a set of expected values of a series of operators has been used. To numerically solve this set of coupled expectation values, the matrix continued fractions method is used. How the changes of the physical quantities including the atomic population inversion, mean photon number and second-order correlation function have been studied for any transition. Finally, the process of converting the four-level atom to a three-level one under several specific conditions is discussed for each transition. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 171 180 https://ijpr.iut.ac.ir/article_1683_39a377cf81a4ff2ba3fc0a07e311fd8e.pdf dx.doi.org/10.47176/ijpr.21.1.81111 Berezin’s quantization approach for determining the ladder operators associated ‎to a movement particle on the circle and sphere S Rezaei Department of Physics, Razi University, Kermanshah, Iran author A Rabeie Department of Physics, Razi University, Kermanshah, Iran author text article 2021 per The quantum formulation of a physical system is essentially based on the associated creation and annihilation operators. In this article, we introduce these ladder operators for a movement particle on the circle and 2-dimensional sphere by Berezin’s quantization .This approach is derived from the resolution of the unity condition in coherent states. In other words, the coherent states provide a straight forward quantization scheme from a classical state to corresponding quantum state. In this article, we study the coherent states of these systems from heat kernel function point of view. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 181 187 https://ijpr.iut.ac.ir/article_1684_8878f4397d58a854a3897479324c0e79.pdf dx.doi.org/10.47176/ijpr.21.1.51054 Optical pulses generation of single-cycle and dual-UWB using square and Gaussian electric pulses A Afroozeh ‎ Department of Electrical Engineering, University of Larestan, Lar, Iran author text article 2021 per - In this paper, a method for generating transverse band (UWB) pulses, the basis of which is a large-scale interferometer with a resonator of small silicone rings capable of changing paired configuration, is reported. Single-cycle, dual-bandwidth signals are generated at the time of the Picosecond pulse, and the small ring amplifier is modulated with square and Gaussian electric pulses, respectively. Microwave photonic systems that work with large optical components suffer from large size, high energy consumption, high cost, and vulnerability to environmental disturbances. Therefore, it is highly desirable to assemble the microwave photonic system on a single chip to make it more compact, cheap, and low-consumption. They have a low spectrum. One of its applications is in short-range wireless telecommunications and high power for wireless transmission of large multimedia data. It can also be used in low speed and power mode for IoT applications such as precision internal positioning. Unlike the WiFi or Bluetooth distance estimation, which is based on signal intensity, the bandwidth signal has a very narrow pulse width, similar to the radar pulse, which enables it to estimate the position using pulse forward time and 10 cm accuracy. With an intensified modulator based on silicon photonics, one can very hopefully generate an adjustable microwave signal on the chip. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 189 196 https://ijpr.iut.ac.ir/article_1685_c59cf02679f27c4bf6b6e5ee8dca0404.pdf dx.doi.org/10.47176/ijpr.21.1.41050 A new thermoluminescence mixed order model considering thermal ‎quenching effect S Harooni Department of Nuclear Physics, Faculty of Physics, University of Kashan, Kashan, Iran author M Zahedifar ‎ Department of Nuclear Physics, Faculty of Physics, University of Kashan, Kashan, Iran Institute of Nanoscience and Nanotechnology, University of Kashan, ‎Kashan, Iran author S Kermani ‎ Department of Nuclear Physics, Faculty of Physics, University of Kashan, Kashan, Iran author E Sadeghi ‎ Department of Nuclear Physics, Faculty of Physics, University of Kashan, Kashan, Iran Institute of Nanoscience and Nanotechnology, University of Kashan, ‎Kashan, Iran author text article 2021 per Thermal quenching as an important and well-known effect in compounds exhibiting thermoluminescence, should be considered in thermoluminescence studies. Among the models describing the thermoluminescence phenomenon, the mixed order kinetic model provides a more realistic description of this behavior. In this work, the Thermal quenching effect is included in the mixed order kinetic model and the new thermoluminescence glow curve deconvolution function is obtained in terms of the maximum intensity and the maximum intensity temperature. The new equation reduces to the known mixed order model by equating the thermal quenching parameter to zero. Also the kinetic parameters of the peak 5 of LiF: Mg, Ti (TLD-100) thermoluminescence dosimeter considering the new equation (with Thermal quenching effect) and the previous equation (without Thermal quenching effect) for different heating rates are determined and the results are compared. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 197 204 https://ijpr.iut.ac.ir/article_1686_c879aa48a917dbb672991c3c907fc64e.pdf dx.doi.org/10.47176/ijpr.21.1.38951 Determination of optimal PSA for the measurement of gross alpha and beta radioactivity in ‎water samples by LSC H Ranjbar ‎ Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, Tehran, Iran author B Salimi ‎ Nuclear Fuel Cycle Research School, Nuclear Science and Technology Research Institute, Tehran, Iran author text article 2021 per Measurement and determination of gross alpha and gross beta radioactivity in water are important in all societies and countries of the world because of their adiobiological risks and is part of the goals of standards and public health organizations. Liquid scintillation counting technique is one of the best methods for simultaneously measuring alpha and beta-particle-emitting in water. In this technique, due to the overlap of spectra of alpha and beta, evaluation of the alpha and beta interference and the appropriate PSA value is very important for sample counting rate. The purpose of this work is to measure the activity concentration of gross alpha and beta in bottled water and compare them with the allowable limit and international standards. To achieve the goal of this research, the work was carried out in two phases. In phase 1, the alpha and beta interference and the appropriate PSA are obtained using two standard solutions of americium-241 and strontium-90 with activity of 21 and 40 Bq. In phase 2, The 10 bottled drinking water samples from different brands are analyzed using LSC. The results of the sample counting showed appropriate PSA value of 110 for the measurement of gross alpha and gross beta radioactivity in water. The measurement results showed that the gross alpha and beta activity concentrations were 41-62 mBqL-1 and 57-85 mBqL-1 which are below the allowable limit by comparing the standard limits. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 205 211 https://ijpr.iut.ac.ir/article_1687_c98876df27c3b7353aa34e9767397e27.pdf dx.doi.org/10.47176/ijpr.21.1.04913 Quasinormal modes of black holes in dRGT massive gravity ‎ under electromagnetic perturbations S H Hendi Department of Physics, School of Science, Shiraz University, Shiraz, Iran; ‎ Biruni Observatory, School of Science, Shiraz University, Shiraz, Iran author M Momennia Department of Physics, School of Science, Shiraz University, Shiraz, Iran; ‎ Biruni Observatory, School of Science, Shiraz University, Shiraz, Iran author text article 2021 per Upon semi-analytical and numerical methods, the quasinormal frequencies of dRGT massive black holes under electromagnetic perturbation are calculated and the dynamical stability of these black holes is investigated. The effect of graviton’s mass on the frequencies is investigated and it is shown that the WKB approximation is valid not only for  but also only for low-mass gravitons. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 21 v. 1 no. 2021 213 218 https://ijpr.iut.ac.ir/article_1688_169cd37b2bd45640cd9b5e00af7fecc1.pdf dx.doi.org/10.47176/ijpr.21.1.01144