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The main goal of this work is to get the fabrication technology of the insertion devices. A prototype undulator with the period of 48mm and the peak magnetic field of 0.75 T has been fabricated using NdFeB-SH35 magnets based on the cooperation between ILSF and NSTRI. The total magnet length is 483 mm and the number of periods is 8. The magnetic parameters of the undulator are determined in order to reach the first and third harmonics. The photon energy should cover 260 eV to 2000 eV range. In order to control the strong attractive magnetic force between the upper and lower arrays, a special mechanical mechanism has been designed and fabricated. The source of errors in the magnetic field has been discussed. The share of each errors has been investigated in the total magnetic field and their effects on the harmonics intensity have been studied. The RMS field error has been obtained to be 0.4%; also, the first and third harmonics intensity reached to more than 80% of the ideal intensities in the presence of the real magnetic field.

Deuteron induced gamma-ray emission cross-section values from the 14N(d,pγ4-1)15N (Eγ = 1885 keV), 14N(d,pγ6-1)15N (Eγ = 2297 keV), 14N(d,pγ5-0)15N (Eγ = 7299 keV) and 14N(d,pγ7-0)15N (Eγ = 8310 keV) nuclear reactions were measured in the 600–2000 keV range of the incident deuteron energies, in 30 keV steps at the laboratory angle of 90°, utilizing a thin C3H6N6 target evaporated onto a self-supporting Ag film. The thick target gamma-ray yields were measured in the same experimental setup using a thick TiN target. These measurements were conducted using the deuteron beam of the 3 MV Van de Graaff electrostatic accelerator of Nuclear Science and Technology Research Institute (NSTRI) in Tehran. The obtained results were compared with the previously reported data. The validity of the measured differential cross sections was verified through a thick target benchmarking experiment. The overall systematic uncertainty of the measured values was estimated and reported.

The unique ionization pattern of MeV-energy ion beam is applied for efficient luminescence analysis of a collection of natural turquoise samples. The considerable penetration depth of tens of micrometer and enhancement of energy deposition with depth, suggests ionoluminescence as an appropriate technique for studying weakly luminescent minerals. Herein, the luminescence induced in deeper parts of turquoise samples is extracted through their relatively transparent adjacent host stones. The resulting intense spectra reveal the vibrational structure of the broad green luminescence band of turquoise which probably originates from O 2 – centers. Moreover, owing to the applied ionoluminescence approach, red and blue luminescence bands of turquoise were observed which can be ascribed to Fe 3 + ions and UO 2 2 + centers respectively. The elemental information of the samples is provided using micro-PIXE analysis technique.

Thick target excitation yield curves of gamma-rays from the reactions 27 Al(p,p′γ) 27 Al (E γ = 844 and 1014 keV), 27 Al(p,αγ) 27 Al (E γ = 1369 keV), 28 Si(p,p′γ) 28 Si (E γ = 1779 keV), 29 Si(p,p′γ) 29 Si (E γ = 1273 keV) and 31 P(p,p′γ) 31 P (E γ = 1266 keV) were measured by bombarding pure-element targets with protons at energies below 3 MeV. Gamma-rays were detected with a High Purity Ge detector placed at an angle of 90° with respect to the beam direction. The obtained thick target gamma-ray yields were compared with the previously published data. The overall systematic uncertainty of the thick target yield values was estimated to be better than ±9%.

A new version of the Iranian Noble Gas Analyzing System (INGAS) has been improved to facilitate measurement of beta-gamma coincidence events. It employs a new prototype list-mode multi-parameter data analyzer system, MPA4300. In order to test the new version performance, it has used to obtain energy spectra from radioxenon isotopes using the detector assembly of the Iranian Noble Gas Analyzing System. The MPA4300 is able to set the coinciding parameters, extract the corresponding spectrum, and through the use of event by event list file, can replay the measurement in offline mode. A great novelty of this work is the use of internal timing circuit in MPA4300 instead of using standard pick up time modules to identify coincidence events of detectors. A detailed description of the measuring 222Rn and 131mXe is presented.

Natural heterogeneous lapis lazuli has been investigated using the complementary techniques of ionoluminescence spectroscopy, ionoluminescence microscopy and micro-PIXE. The equivalent probed depths, the possibility of simultaneous use and the capability of non-destructive in-air application suggest the combined use of ionoluminescence and micro-PIXE techniques as an appropriate approach in mineral analysis to reveal the texture, chemical composition, and elemental distribution of the samples. In this research work, the various mineral phases of a lapis lazuli sample were detected and analyzed. It was possible to identify most of the minerals in the analyzed area, including apatite, a mineral phase uncommon in lapis lazuli, and point out different luminescence features of crystals of the same mineral, diopside, found in different parts of the same lapis lazuli sample.

Differential cross sections of proton induced gamma-ray emission from the 31 P(p,pγ 1 ) 31 P ( E γ = 1266 keV) nuclear reaction were measured in the proton energy range of 1886–3007 keV at the laboratory angle of 90°. For these measurements a thin Zn 3 P 2 target evaporated onto a self-supporting C film was used. The gamma-rays and backscattered protons were detected simultaneously. An HPGe detector placed at an angle of 90° with respect to the beam direction was employed to collect gamma-rays while an ion implanted Si detector placed at a scattering angle of 165° was used to detect backscattered protons. Simultaneous collection of gamma-rays and RBS spectra is a great advantage of this approach which makes differential cross-section measurements independent on the collected beam charge. The obtained cross-sections were compared with the previously only measured data in the literature. The validity of the measured differential cross sections was verified through a thick target benchmarking experiment. The overall systematic uncertainty of cross section values was estimated to be better than ±9%.

In this research work, measured differential cross sections for gamma-ray emission from the nuclear reactions 35 Cl(d,p γ 1-0 ) 36 Cl ( E γ = 788 keV), 35 Cl(d,p γ 2-0 ) 36 Cl ( Eγ = 1165 keV), 37 Cl(d,p γ 1-0 ) 38 Cl ( E γ = 671 keV) and 37 Cl(d,p γ 2-0 ) 38 Cl ( E γ = 755 keV) are presented. For these measurements a thin natural BaCl 2 target evaporated onto a 50 μm-thick Mo foil was used. The gamma-rays and backscattered deuterons were detected simultaneously. An HPGe detector placed at an angle of 90° with respect to the beam direction was employed to collect gamma-rays while an ion implanted Si detector placed at a scattering angle of 165° was used to detect backscattered deuterons. The validity of the obtained differential cross sections was verified through a thick target benchmarking experiment. The overall systematic uncertainty of cross section values was estimated to be ±10%.

Differential cross sections of the 24 Mg(d,p 0,1,2,3,4 ) reactions were obtained in the range E d,lab = 1.2–2 MeV and at the scattering angles of 90°, 135°, 150° and 165° using a thin Mg target having thickness of 76.7 ± 3.1 μg/cm 2 . The cross section values were determined with an average energy step of ∼25 keV while the detailed measurements were carried out with an energy step of ∼5 keV around the resonance peaks. Elastic scattering data for three steep backward angles (135°, 150° and 165°) were also studied for the same incident deuteron energy range and steps. The results were compared with those of the previous studies. Moreover, the validity of the measured data has been benchmarked using a thick Mg target at two deuteron beam energies of 1.7 and 2 MeV.

This paper describes two modifications in the pure permanent magnet (PPM) undulators: 1) phase shift and 2) magnetization rotation, and studies their effects on the radiation harmonics properties. An analytical description for these modifications has been presented and two numerical codes, RADIA and B2E, have been used to model the PPM undulator in the presence of the aforementioned modifications and to calculate their effects on the synchrotron radiation properties. A short description of these codes has been presented. The two most important properties of the harmonics are their energy and intensity. This paper uses a simple theoretical approach to show that the phase shift mechanism can affect the ${K}$ -value of the undulator and then change the harmonics energy and their intensity, while the rotation mechanism does not change harmonics properties notably. Recently, a new combined method called phase combined undulator (PCU) has been supposed. The PCU structure has been fabricated using the phase shift mechanism and applying a specific magnets arrangement to eliminate the magnetic force between upper and lower arrays. The radiation harmonic generation of this structure has been studied.

In the present work, differential cross section values of the 16O(d,d0) reaction were obtained for Ed,lab = 900–2000 keV, at four scattering angles, namely at 90°, 135°, 150° and 165° using a thin SiO target having a thickness of (910 ± 36) × 1015 at/cm2. The cross section values were determined with an energy step of ∼10 keV while, the detailed measurements were carried out with an energy step of ∼5 keV around the resonance peaks. The results were compared with those of the previous studies.

Most of the GEM/THGEM-based microdosimetric detectors presented in the literature simulate 2 μm of tissue which results in a flat neutron dose-equivalent response in the MeV region. The objective of this work was to introduce a neutron microdosimeter with a more extended flat response. In this regard, a THGEM-based microdosimeter with plexiglas walls, simulating 1 μm of tissue was designed and constructed. Its performance was investigated by both simulation and experimentation to determine the microdosimetric quantity of “lineal energy”. In the simulation study, lineal energy distribution, mean quality factor and dose-equivalent response of the microdosimeter for eleven neutron energies from 10 keV to 14 MeV, along with the energy spectrum of 241 Am-Be neutrons, were calculated by the Geant4 simulation toolkit. Obtained lineal energy distributions were compatible with the distributions determined by a Rossi counter. Also, the mean quality factors agreed well with the values reported by the ICRU report 40 which confirmed tissue equivalent behavior of the microdosimeter. They were different from the effective quality factor values within 15% between 20 keV and 14 MeV. This led to a flat dose-equivalent response with 20% difference from a median value of 0.82 in the above energy range which was an improvement compared with other THGEM-based detectors, simulating 2 μm of tissue. In spite of the satisfactory determination of the dose-equivalent, the microdosimeter had low detection sensitivity. In the experimental study, the measured lineal energy distribution of 241 Am-Be neutrons was in agreement with the simulated distribution. Further, the measured mean quality factor and dose-equivalent differed by 1.5% and 3.5%, respectively, from the calculated values. Finally, it could be concluded that the investigated microdosimeter reliably determined the desired dose-equivalent value of each neutron field with every energy spectrum lying between 20 keV and 14 MeV.

Reliable performance of the Ion Beam Analysis (IBA) techniques is based on the accurate geometry of the experimental setup, employment of the reliable nuclear data and implementation of dedicated analysis software for each of the IBA techniques. It has already been shown that geometrical imperfections lead to significant uncertainties in quantifications of IBA measurements. To minimize these uncertainties, a user-friendly experimental chamber with a heuristic sample positioning system for IBA analysis was recently developed in the Van de Graaff laboratory in Tehran. This system enhances IBA capabilities and in particular Nuclear Reaction Analysis (NRA) and Elastic Recoil Detection Analysis (ERDA) techniques. The newly developed sample manipulator provides the possibility of both controlling the tilt angle of the sample and analyzing samples with different thicknesses. Moreover, a reasonable number of samples can be loaded in the sample wheel. A comparison of the measured cross section data of the 16O(d,p1)17O reaction with the data reported in the literature confirms the performance and capability of the newly developed experimental chamber.

Nuclear Reaction Analysis (NRA) and more specifically d-NRA is a suitable technique for 16 O detection on or near surface of a compound containing heavy elements. The main problem of d-NRA is the limited number of NRA differential cross section data sets and their differences. The differential cross sections of 16 O(d,p 0,1 ) reactions were measured in the present work for E d,lab = 700–1800 keV, at four scattering angles, namely at 90°, 135°, 150° and 165° which are suitable for NRA. Differential cross sections were collected with an energy step of ∼10 keV. However, detailed measurements were carried out with an energy step of ∼2 keV around resonances. The results are compared with previous studies and the similarities and differences are discussed.

Ion beam induced luminescence (IBIL) is introduced as a powerful luminescence technique for analyzing the gemstones. Although IBIL is basically comparable to cathodoluminescence (CL), as a well-known luminescence method for studying the gemstones, its high energy density, superior flexibility in depth resolving and fast ionization rate, qualify it for studying weakly luminescent, multi-layer, and precious samples. In order to examine the potential of IBIL in analyzing the gemstones, three samples of beryl (aquamarine variety), opal, and topaz, with different luminosities, were studied through simulations and experiments. The results of the Monte Carlo simulations of the proton beam in interaction with the mentioned gemstones, displayed the capabilities of IBIL, especially in comparison to the well-known technique of CL. The in-air ion beam induced luminescence experiments of the natural samples were performed at room temperature. Also, the complementary technique of microPIXE was applied for elemental analyses of the samples. The promising results of the IBIL experiments exhibit the ability of the technique for analyzing weakly luminescent gemstones, such as aquamarine. The IBIL spectra also exhibit some unknown luminescence bands, which are mostly located in the UV part of the spectra. These new bands disclose the existence of the unknown luminescence activators in the samples. Possible ideas on the origins of these new bands are proposed.

Differential cross sections for gamma-ray emission from the 28 Si(p,p / γ) 28 Si ( E γ = 1779 keV) and the 29 Si(p,p / γ) 29 Si ( E γ = 1273 keV) nuclear reactions were measured in the energy range of 2.0–3.2 MeV and 2.0–3.0 MeV, respectively. The thin Si targets were prepared by evaporating natural SiO onto self-supporting Ag films. The gamma-rays and backscattered protons were detected simultaneously. An HPGe detector placed at an angle of 90° with respect to beam direction was employed to collect gamma-rays while an ion implanted Si detector placed at a scattering angle of 165° was used to detect backscattered protons. The great advantage of this work is that differential cross sections were obtained with a procedure irrespective of absolute value of the collected beam charge.

In the present work, the energy loss and the dechanneling of He ions in the energy of 1.5 MeV and 2 MeV along the 〈1 0 0〉 and 〈1 1 0〉 axial directions as well as the {1 0 0} and {1 1 0} planar directions of Si were studied by the simulation of the channeling Rutherford backscattering spectra. The simulation was done based on the considerations that a fraction of the aligned beam enters the sample as a random component due to the ions scattering from the surface, and the dechanneling starts at the greater penetration depths, xDech. It was presumed that the dechanneling process follows a simple exponential law with a parameter λ which is proportional to the half-thickness. The Levenberg–Marquardt algorithm was used to set the best parameters of energy loss ratio, xDech and λ. The experimental results are well reproduced by this simulation. Differences between various axial and planar channels in the Si crystal and their influence on the energy loss ratio and dechanneling of He ions are described. Moreover, the energy dependence of energy loss ratio and dechanneling of He ions were investigated. It is shown that the dechanneling behavior of ions depends on the energy and energy loss of the ions along a channel. The channeled to random energy loss increases by decreasing ions energy.

In this work measurement of differential cross sections of 27Al(p,p/γ)27Al (Eγ = 844, 1014 keV) and 27Al(p,αγ)24Mg (Eγ = 1369 keV) nuclear reactions in the proton energy range of 1.6–3.0 MeV are described and the measured values are presented. Thin Al target was prepared by evaporating a 26 μg/cm2 Al onto a 129 μg/cm2 self-supporting Ag film. The gamma-rays and backscattered protons were detected simultaneously. The gamma-rays and protons were collected by an HPGe detector placed at an angle of 90° with respect to beam direction and an ion implanted Si detector placed at a scattering angle of 165°, respectively. In this experimental setup the great advantage is that differential cross sections could be independent on absolute values of the collected beam charge. The overall systematic uncertainty of cross sections was estimated to be ±9% while statistical errors were less than ±5%.

One of the most commonly used types of accelerators is linear electron accelerator. There is a project is in progress in Institute for research in fundamental sciences (IPM) aiming to design and build such an accelerator. It is defined in such a way that all parts to be built in Iran as possibly as it can. In this paper, after a brief explanation of the components of an electron linear accelerator; including the electron gun, accelerating tube, RF power supply, vacuum system, waveguide for transmitting RF power to accelerating tube, and cooling system; specification of each of these components are presented. The maximum beam energy of 15 MeV and RF pulse power of 2.5 MW with a traveling wave structure at a frequency of 2998 MHz which is acted in π /2 mode are the most important features of this accelerator

در این مقاله خطوط باریکه روز اول راه ‌اندازی چشمه نور ایران و مشخصات آن‌ها معرفی می‌شوند. از میان این خطوط باریکه، طراحی مفهومی دو خط باریکه طیف سنجی میکروسکوپیکی، و پراش پودری، به عنوان پرکاربردترین خطوط باریکه، انجام شده است. در این مقاله به بررسی مشخصه­های پرتو چشمه نور، طراحی اپتیکی، مشخصات - شار فوتونی در مکان نمونه 6-30keVقطعات‌ و ردیابی پرتو فوتون در این خطوط باریکه پرداخته شده است. خط باریکه پراش پودری محدوده انرژی کارکردی را دارد. محدوده انرژی خط باریکه طیف ­سنجی میکروسکوپیکی E/E=10-4Δ وقدرت تفکیک‌انرژی 0/1×0/1-10×1mm2 سطح مقطع پرتو فوتونی در مکان نمونه برابر با96eVاست که از یک مغناطیس نوسان‌ساز خطی گسیل می‌شود. بیشینه شار فوتون گسیل شده در انرژی هارمونیک اصلی eV90-2500 پرتو فوتونی با بیشینه توان تفکیک‌پذیری18201000 eVاستهمچنین، در انرژی در مکان نمونه ایجاد می‌شودH×V= 4×2- 27×74μm و سطح مقطع در محدود

In this paper, the importance and applications of accelerators in today’s world have been investigated. A survey on diverse applications of accelerators in modern world’s issues and their growth in various fields of technology has been conducted. In addition, some statistics of miscellaneous accelerator numbers in different countries and a comparison of them with present situation in Iran’s statistics are presented

In this paper, the channeling behavior of deuterons in the energy of 1400 keV along the channel of Si was studied by the simulation of the channeling Rutherford spectrum in the backscattering geometry. The simulation was done by taking three considerations into account: (i) a minimum random component of the beam which enters the sample because of the scattering ions from the surface, (ii) the dechanneling starts at the greater penetration depths and (iii) the dechanneling follows a Gompertz type sigmoidal function with the two parameters which present the dechanneling rate and range, respectively. The Levenberg–Marquardt algorithm was used to set the best characteristic channeling parameters, the penetration depth at which the dechanneling starts, the energy loss and the dechanneling rate and range. The energy dependence of the ratio of channeling to random energy loss of deuterons in the energy range 1–2 MeV is investigated by comparing the determined value with the ones obtained in the other references.

It had long been thought that obsidian found in Iranian sites originated from Anatolia and Armenia, but new research has challenged this assumption. In this study, 68 samples of obsidian obtained from an archaeological survey of Nader-Tepe Aslanduz were analyzed by Proton Induced X-ray Emission (PIXE). Nader-Tepe Aslanduz is a tell site west of the city of Aslanduz in the Parsabad county of the Ardebil province in northern Iran. The site was inhabited from the first millennium B.C. to A.D. 17, and its history may extend back to the third or fourth millennium B.C. Our chemical composition results have been combined with obsidian composition data from Turkey and Armenia and subjected to Principal Component Analysis (PCA). This analysis shows that obsidian from each location can be grouped into distinctive classes—the obsidian from Nader-Tepe Aslanduz is therefore probably derived from volcanic outcrops of the Sahand and Sabalan region. This study has been unable to assign a known source from Anatolia and Armenia for the obsidian of Nader-Tepe Aslanduz.

Refurbishment of hot components of gas turbines damaged in the harsh working environments is necessary to increase their lifetime. Scanning proton microscopy was employed to evaluate the quality of refurbishment process of gas turbine blades. Distribution patterns of different elements were observed in the polished cross-sections of turbine blade samples by proton microbeam. In the cross-sections of refurbished and used samples, distinct regions were identified corresponding to the base superalloy, original protection layer and applied coating for refurbishment. The elemental composition of each of these regions was measured by Micro-PIXE analysis. Inhomogeneous and high content of Si as well as undesired light elements were observed in the cross-sections of refurbished samples, indicating imperfections in the refurbishment process.