Calculation of proton-deuteron breakup scattering cross section in intermediate energies
m
Harzchi
دانشکده فیزیک، دانشگاه صنعتی خواجه نصیرالدین طوسی
author
sh
Bayegan
دانشکده فیزیک، دانشگاه تهران
author
text
article
2019
per
In this paper, we reformulate three-nucleon breakup scattering in leading order approximation by considering spin-isospin degrees of freedom. At first, considering the inhomogeneous part of Faddeev equation, which is a valid approximation in high and intermediate energles, we present the Faddeev equation as a function of vector Jacobi momenta and spin and isospin quantum numbers. In this new formulation, a three-dimensional representation of deuteron wave function instead of its partial wave representation. Then, this equation is rewritten in suitable coordinate system as a function of vector magnitudes and angles between them for numerical calculation. Finally, by applying the Bonn-B potential the proton-deuteron breakup scattering cross section is calculated and the results are compared with the experimental data.
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
1
6
http://ijpr.iut.ac.ir/article_1061_ccc7b5e88a0b34b74f37e76748dc1a81.pdf
Effect of dielectric medium on the nonclassical properties of nonlinear sphere coherent states
E
Amooghorban
گروه فیزیک، دانشکده علوم پایه، دانشگاه شهرکرد، شهرکرد
author
A
Mahdifar
گروه فیزیک، دانشکده علوم پایه، دانشگاه شهرکرد، شهرکرد
author
text
article
2019
per
In order to investigate the effect of a medium with dissipation and dispersion and also the curvature of the physical space on the properties of the incident quantum states, we use the quantization of electromagnetic field based on phenomenological approach to obtain input-output relations between radiations on both sides of dielectric slab. By using these relations the fidelity, the Wigner function, and also the quantum correlation of the outgoing state through dielectric slab are obtained for a situation in which the rightward incident state is a nonlinear coherent state on a sphere and the leftward incident state is a vacuum state. Here, the incident states are considered monochromatic and the modeling of the medium is given by the Lorentz' model. Accordingly, we study nonclassical properties of the output states such as the quantum entanglement. It will be observed that the nonclassical properties of the outgoing states depend strongly on the optical property of the medium and also on the curvature of the physical state.
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
7
25
http://ijpr.iut.ac.ir/article_1062_52eca7a3f3a0ae25fe13fe0517902265.pdf
Effect of extra nonmagnetic Ga atoms on lattice ordering and magnetic properties of Fe2CoGa and Co2FeGa Heusler compounds
محسن
Hakimi
گروه نانوفیزیک و مغناطیس، دانشکده فیزیک، دانشگاه یزد
author
محسن
Khajeh Aminian
گروه نانوفیزیک و مغناطیس، دانشکده فیزیک، دانشگاه یزد
author
text
article
2019
per
Arc-melting with ball milling was used for preparing Fe2CoGa1+x and Co2FeGa1+x (x=0,0.2) Heusler samples. Effect of extra nonmagnetic Ga atoms on lattice ordering and magnetic properties of Fe2CoGa and Co2FeGa Heusler compounds was studied. Rietveld refinement showed that lattice parameter of the samples increases in the presence of extra Ga atoms. Results showed that Co2FeGa1.2 has a partial lattice disordering. Saturation magnetization of Co2FeGa sample was lower than Slater – Paulig prediction due to the crystallite size on a scale of nanometer. Reduction of saturation magnetization by increasing Ga atoms was explained through the change of lattice parameter, lattice ordering, and crystallite size. Saturation magnetization of Fe2CoGa sample was greater than Slater – Paulig value. Change of lattice parameter by increasing Ga atoms resulted a decrease of saturation magnetization in Fe2CoGa1.2
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
26
31
http://ijpr.iut.ac.ir/article_1063_423c162c20bfbfdba87f491e813584a2.pdf
Study of the electronic and magnetic properties of A2Ti2O7 (A=Er, Tb)
E
Khorasani
دانشکده فیزیک، دانشگاه صنعتی اصفهان
author
N
Deylinazar
دانشکده فیزیک، دانشگاه صنعتی اصفهان
author
M
Alaei,
دانشکده فیزیک، دانشگاه صنعتی اصفهان
author
F
Shahbazi
دانشکده فیزیک، دانشگاه صنعتی اصفهان
author
text
article
2019
per
The geometrical frustration in the magnetic pyrochlore oxides causes interesting properties at low temperatures in these materials. Therefore, we studied two challenging materials, Er2Ti2O7 and Tb2Ti2O7, using an ab intio method, based on Density Functional Theory (DFT). To take into account the f electrons coulomb interactions correctly, we employed DFT+U, a Hubbard method correction. As spin-orbit coupling (SOC) is very effective in these materials, we added SOC to the DFT+U calculations (DFT+U+SOC). Using DFT+U+SOC, we examined the effect of non-collinear magnetism. The DFT+U+SOC calculations give rise to the magnetic moments 8.2 and 7.1 for Er2Ti2O7 and Tb2Ti2O7, respectively. These values deviate from the experimental results. The reason is that the DFT calculations are trapped in the local minima, indicatinglhat we need more sophisticated methods to find the global minimum in our electronic structure calculations. Although we need structural optimization to find better magnetic moment values, unfortunately it is possible to reach incorrect structural optimization if the electronic structural optimization for finding global minima is not performed correctly
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
33
44
http://ijpr.iut.ac.ir/article_1064_db5966963c8180e92567d54f5bef2671.pdf
Investigation of behavior of scintillator detector of Alborz observatory array using Monte Carlo method with Geant4 code
M.
Abbasian Motlagh
گروه فیزیک، دانشکده علوم پایه، دانشگاه بینالمللی امام خمینی، قزوین
author
D.
Purmohammad
گروه فیزیک، دانشکده علوم پایه، دانشگاه بینالمللی امام خمینی، قزوین
author
Y.
Pezeshkian
دانشکده فیزیک، دانشگاه صنعتی شریف، تهران
author
text
article
2019
per
For their appropriate temporal resolution, scintillator detectors are used in the Alborz observatory. In this work, the behavior of the scintillation detectors for the passage of electrons with different energies and directions were studied using the simulation code GEANT4. Pulse shapes of scintillation light, and such characteristics as the total number of photons, the rise time and the falling time for the optical pulses were computed for the passage of electrons with energies of 10, 100 and 1000 MeV. Variations of the characteristics of optical pulse of scintillation with incident angle and the location of electrons were also investigated
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
45
54
http://ijpr.iut.ac.ir/article_1065_6a512aeb9d4e23ef0d2139d586e86b4d.pdf
Designing single-qutrit quantum gates via tripod adiabatic passage
M.
Amniat-Talab
گروه فیزیک، دانشکده علوم، دانشگاه ارومیه
author
S.
Golkar
گروه فیزیک، دانشکده علوم، دانشگاه ارومیه
author
S.
Nasser
گروه فیزیک، دانشکده علوم، دانشگاه ارومیه
author
text
article
2019
per
In this paper, we use stimulated Raman adiabatic passage technique to implement single-qutrit quantum gates in tripod systems. It is shown by using the Morris-Shore (MS) transformation, the six-state problem with 5 pulsed fields can be reduced to a basis that decouples two states from the others. This imposes three pulses not connected to the initial condition with have the same shape. Using this method, the six-state penta-pod system is reduced to a tripod system. We can design single-qutrit quantum gates by ignoring the fragile dynamical phase, and by suitable design of Rabi frequencies of the effective Hamiltonian
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
55
64
http://ijpr.iut.ac.ir/article_1066_f1c051716e22cbb9d3222357b0630528.pdf
Automated tracking of solar coronal loops and detection of their oscillations
S.
Taran
دانشکده فیزیک، دانشگاه زنجان، زنجان
author
H.
Safari
دانشکده فیزیک، دانشگاه زنجان، زنجان
author
N.
Farhangh
دانشکده فیزیک، دانشگاه زنجان، زنجان
author
text
article
2019
per
Identification and tracking of solar coronal loops is key to understanding solar magnetic field. Slow and fast Magnetohydrodynamic oscillation of tracked loops from sequence 171Å extreme ultra – violet images was detected. The method was demonstrated using 171Å images taken by SDO/AIA on 14 August 2010 and 20 January 2012. Two dimensional continuous wavelet transform (CWT) was used to clarify images of loops and to eliminate additional noises. Applying OCCULT method, the loops were labeled and their widths were determined. The Zernike moments of loops as an invariant property (transformation, scale and rotation) of loops were calculated. Then, the Probabilistic Neural Network (PNN) was used for identification of the same loops from sequence images. Slow longitudinal Magnetohydrodynamic oscillations were extracted by averaging pixels intensities perpendicular to tube axis. Fast oscillations in distinguishable tubs were observed observable by averaging pixels’ intensities in direction of tube axis. Also, periods, phase velocity, and damping time of oscillations were computed
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
65
72
http://ijpr.iut.ac.ir/article_1067_438746bb5b7f20203f7ed2268de0033b.pdf
Hydrogen sensing performance of WO3 thin film by using multi - wall carbon nanotubes
R.
Ghasempour
دانشکده علوم و فنون نوین، گروه انرژیهای نو و محیط زیست دانشگاه تهران
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
A.
Irajizad
دانشکده فیزیک، دانشگاه صنعتی شریف
author
text
article
2019
per
The WO3/MWNTs hybrid gas sensitive films were prepared by spin-coating on alumina substrate. The structure, morphology and chemical composition of the functionalized MWNTs and WO3/MWNTs hybrid films were studied by SEM, TEM, XRD, Raman, DLS and XPS methods. The MWCNT were initially functionalized (f-MWNTs). Dispersion and surface reactivity of MWNTs was improved because of oxygenate groups on MWNTs surface. Results showed WO3 nanoparticles were nucleated on oxygenated group on surface of f-MWNTs in hybrid suspension. After coating and annealing the films at 350 , the response of hybrid WO3/MWNTs films was measured. In addition, adding a little amount of MWNTs (the ratio of MWNTs/W less than 5/1000 wt%) increased the hydrogen sensitivity so that the hybrid films showed an increase of 50 times compared to pure tungsten oxide layer in response to the 10000 ppm hydrogen concentration. Considering the results, the identification of these structures appear tobe 10 ppm hydrogen gas. With the addition of carbon nanotubes, the working temperature of pure tungsten oxide layers (400 ) reduced to 200 in hybrid layer. The gas sensitivity is suggested to have risendue to mainly the increase in the surface area as well as development of two types of depletion layers, one at the WO3/ MWNTs hetero junction and the other at WO3 grain boundaries.
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
73
81
http://ijpr.iut.ac.ir/article_1068_f8934d8a02c7d91aeb7ab9855a431d40.pdf
Electron acceleration in an ion channel by a magnetized plasma wave
A.
Kargarian
پژوهشگاه پلاسما، دانشگاه خوارزمی، تهران
author
H.
Mehdian
پژوهشگاه پلاسما، دانشگاه خوارزمی، تهران
author
A.
Hasanbeigi
پژوهشگاه پلاسما، دانشگاه خوارزمی، تهران
author
text
article
2019
per
In this paper, the acceleration of an electron in the interaction with a plasma wave and a magnetized ion-channel is analyzed. The electron dynamics is studied treated employing complete three-dimensional Lorentz force equations. A relativistic three dimensional single particle code is used to obtain the electron-trajectories. The results of numerical calculation show that the electrons can be accelerated in the magnetized channel. Furthermore, the electron energy gain with axial magnetic field is compared to that without axial magnetic field.
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
83
87
http://ijpr.iut.ac.ir/article_1069_e0806d75c25f00a5d6791c4d9b96e24c.pdf
A star identification algorithm based on a voting scheme for star trackers
M.
Hamidi
گروه مهندسی نقشهبرداری، پردیس دانشکدههای فنی، دانشگاه تهران
author
F.
Samadzadegan
گروه مهندسی نقشهبرداری، پردیس دانشکدههای فنی، دانشگاه تهران
author
text
article
2019
per
Star identification is one of the most important stages in attitude determination with star trackers. This can be performed using matching algorithms between observed stars and a master star catalogue. The main challenge in this approach is to provide a fast and reliable identification algorithm that is sufficiently robust in different pointing views of the star tracker optical system in the space. In this article, an identification algorithm based on a geometric voting scheme is presented. In this algorithm a pair of stars in the catalogue votes for a pair of stars in the image if angular distance between the stars of both pairs is similar. As angular distance is a symmetric relationship, each of the two catalogue stars votes for each of the image stars. The identity of each star in the image is set to the identity of the catalogue star which cast the most votes. Applying the algorithm in different attitudes and with different optical system parameters shows its high performance in star identification in our simulations.
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
89
105
http://ijpr.iut.ac.ir/article_1070_110d28e00b55144f52c2eb24672a9ac8.pdf
The effect of compressive viscosity on the slow mode oscillations of inhomogeneous solar coronal loops
A.
Abedini
گروه فیزیک دانشگاه قم، قم
author
T.
Bahreininejad
گروه فیزیک دانشگاه قم، قم
author
text
article
2019
per
In this paper, the effect of compressive viscosity on the slow mode oscillation of solar corona loops is studied. The coronal loops medium are considered in low beta condition, uniform magnetic field in the presence of gravitational stratification and temperature gradient. Two-dimensional Magneto-Hydro-Dynamics (MHD) equations are perturbed about the equilibrium and thenthese equations are linearized and ultimately a second order differential equation is obtained for velocity perturbation by stretching method. In considering the appropriate boundary conditions for the differential equationis solved analytically and numerically. Oscillation Modes obtained from numerical solutions with real data from satellites such as SOHO, TRACE and SDO are compared. Results show that the gravitational layering, fluctuations in the corona loop for frequency values greater than the cutoff frequency occurs. In small longitudes, viscosity damping is strong . Since the observations confirms strong damping of oscillations corona, can be said viscosity alone can justify the oscillation damping in elongated loops, the oscillation period is between 2 and 48 min, corresponds to the actual data.
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
107
116
http://ijpr.iut.ac.ir/article_1071_9455ad40311acab56ff7b294958846db.pdf
Effect of the change in ellipticity of the elliptic elements on band structure for 2D photonic crystal waveguide
S. H.
Zahraei
گروه فیزیک، دانشگاه پیام نور، مرکز شیراز
author
A.
Gharaati
گروه فیزیک، دانشگاه پیام نور، مرکز شیراز
author
text
article
2019
per
In this paper, using plane ware expansion method the polarization-dependent band structures are investigated in two dimensional photonic crystal waveguide with a square lattice composed of GaAs elliptic elements in air background. Then, the changes of the band structure with changing ellipticity of the elliptic elements are discussed. It is observed that by increasing the ellipticity of elements the size of the photonic band gap and the guiding eigen frequency will increase
Iranian Journal of Physics Research
https://www.psi.ir/physics_society_iran_1_home
1682-6957
14
v.
1
no.
2019
117
122
http://ijpr.iut.ac.ir/article_1072_8c6a37c6a59d8f2d1a62e203e2027303.pdf