investigating space radiation
Pedram Hajipour; Leila mohammadi; Azam Eidi; Sara Shoorian; Nahid Eidi Esfiani; Seyed Amir Hossein Feghhi
Volume 16, Issue 4 , December 2023, , Pages 15-27
Abstract
One of the damaging factors for the proper functioning of telecommunication payloads are high energy ionizing particles in space, which the use of proper shield is a way to deal with it. In the design of protection, several factors, such as the type of part and the amount of weight acceptable for the ...
Read More
One of the damaging factors for the proper functioning of telecommunication payloads are high energy ionizing particles in space, which the use of proper shield is a way to deal with it. In the design of protection, several factors, such as the type of part and the amount of weight acceptable for the payload.etc.must be taken into consideration. In recent years, in order to reduce the costs of construction and launch, the use of non-space components has been favored.Therefore, the use of shields with the suitable material in with radiation resistance, with respect to the weight budget considerations, will be one of the important challenges .In this paper, the aim is to investigate the methods of reducing the weight budget considering with respect to the radiation damage of ionizing dose. In this regard, a five-year technology development mission in the GEO orbit has been predicted, and the results of simulations and testing of aluminum and polyethylene shielding to check ionizing dose damage, according to the initial and reference weight budget, have been presented and compared. The analysis and evaluation of the test results using polyethylene protection shows a 17.21 percentage reduction between the two external and internal radiation meters.
investigating space radiation
Sarah Shoorian; S. Amir Hossein Feghhi; Hamid Jafari; Reza Amjadifard
Volume 16, Issue 2 , June 2023, , Pages 19-26
Abstract
Protection of astronauts and electronic components in satellites and spacecraft against space rays is one of the most important primary requirements in space missions. In this work, the effect of three materials, aluminum, as the most common material, polyethylene and a graded-z structure, in the protection ...
Read More
Protection of astronauts and electronic components in satellites and spacecraft against space rays is one of the most important primary requirements in space missions. In this work, the effect of three materials, aluminum, as the most common material, polyethylene and a graded-z structure, in the protection of space radiations has been evaluated. The calculations of the dose caused by these radiations on the human body and a silicon piece have been carried out by MCNPX Monte Carlo code,. The dose caused by cosmic rays has been calculated after applying shields of aluminum, graded-z structure and polyethylene. The results showed that by using polyethylene and about 4.4% increase in weight compared to the aluminum shield, it is possible to reduce the dose caused by photons by more than 50% in the human body and 30% in silicon parts, and the dose caused by protons by about 30%. It cut both for astronauts and electronic components. Graded-z shielding performed very well in the dose attenuation caused by photons, but appeared ineffective in the dose attenuation caused by protons.
investigating space radiation
Sara Shoorian; Hamid Jafari; S. Amir Hossein Feghhi; Gholamreza Aslani
Volume 13, Issue 4 , December 2020, , Pages 71-79
Abstract
The presence of ionizing radiation in the space environment, due to trapped particles, solar particles and cosmic rays can be a serious threat to the proper functioning of electronic components used in satellites and spacecraft. In this work, the leakage current variation of a silicon diode, as the basic ...
Read More
The presence of ionizing radiation in the space environment, due to trapped particles, solar particles and cosmic rays can be a serious threat to the proper functioning of electronic components used in satellites and spacecraft. In this work, the leakage current variation of a silicon diode, as the basic element of many electronic components, has been investigated in the exposure of space protons. For this purpose, the GEANT4 Monte Carlo code has been used to calculate the non-ionizing energy loss in the device. The simulation of electrical parameters for irradiation of space protons were also done by SILVACO software. The results show that the leakage current increases by about 1.85 times the amount of it before irradiation, up to about 96.2 nA/μm by the increase in the proton flux up to 2.1×1012 p/cm2. Irradiation of BPW34 photodiodes under 30 MeV protons was performed to validate the results of simulation.
S. Boorboor; S. A. H. Feghhi; H. Jafari
Volume 6, Issue 4 , January 2014, , Pages 23-28
Abstract
Shape and size of sensitive volume are the most important parameters to model electronic devices for calculation of the SEU rate from space radiations. So far different models have been proposed for estimation of the sensitive volume. In this work, results of three models including RPP, Tetrahedral and ...
Read More
Shape and size of sensitive volume are the most important parameters to model electronic devices for calculation of the SEU rate from space radiations. So far different models have been proposed for estimation of the sensitive volume. In this work, results of three models including RPP, Tetrahedral and Nested in calculation of sensitive volume have been compared with experimental result for AT60142 SRAM. GEANT4 as a Monte Carlo code has been used to calculate energy loss and energy straggling of ions with considering metallization and oxide layers. Comparisons between Monte Carlo and experimental results shows that RPP model estimates the SEU cross section with a large deviation in whole LET range, tetrahedral has good response in low LET's but don't follow experimental result for high LET particles and nested sensitive volume produce acceptable results for whole of LET range.
A. Esmaeilian; S. A. H Feghhi; H. Jafari; A. Pahlavan
Volume 6, Issue 3 , October 2013, , Pages 55-60
Abstract
Space radiation environment has concerned about proper performance of electronic systems and equipment used in the space due to a variety of space radiations. The radiation hardening techniques are required to all parts of the system in such environment. Therefore careful studies should be done on the ...
Read More
Space radiation environment has concerned about proper performance of electronic systems and equipment used in the space due to a variety of space radiations. The radiation hardening techniques are required to all parts of the system in such environment. Therefore careful studies should be done on the mechanism of radiation damage in these systems. Shielding is one of radiation hardening technique. The radiation effects on electronic components can be done using radiation simulating softwares. In this work, displacement damage, vacancies and ionization values in silicon and gallium arsenide with layers of metal as a shield have been calculated using TRIM software. The results showed that the more thickness and more elements with high atomic number of shield made more resistance to radiation. Thus, damage in electronic devices would be less. Also, the damages resulted from the incident beam of helium ions is much higher than that of hydrogen ions.
A. Hosseini; S. A. Feghhi; H. Jafari; M.B Aghaei
Volume 6, Issue 2 , July 2013, , Pages 11-19
Abstract
When the electronic components are exposed to neutron irradiation, electrical properties change by interaction of neutrons in these parts such as capacitance, reverse bias current, the minority carrier lifetime, etc. These changes are very important, so that may impair the performance of the device and ...
Read More
When the electronic components are exposed to neutron irradiation, electrical properties change by interaction of neutrons in these parts such as capacitance, reverse bias current, the minority carrier lifetime, etc. These changes are very important, so that may impair the performance of the device and disable it. So the measurement of the damage by neutrons in these parts is necessary. One of the most important parameters for expressing the damage to electronic components is a constant, α that is the inverse current of the damage.The constant (α) is the slope of the reverse current curve versus the radiation flux. The aim of this work is measurement of the damage reverse current of constant α for diodes 1N4007, BYV27 and BYV95 in various voltages and temperatures.These diodes have been irradiated at the Tehran Research Reactor by fission neutron spectrum.The results are in good agreement with the theoretical relations.
