scholarly journals Study on Induced Current of Iron Plate Irradiated by Pulsed Gamma Rays

2018 ◽  
Vol 53 ◽  
pp. 01007
Author(s):  
Yinghong Zuo ◽  
Maoyu Zhang ◽  
Guoxin Cheng ◽  
Shengli Niu

To obtain the transient current response law of the metal component irradiated by pulsed gamma rays, the pulsed gamma ray irradiation experiment of the iron plate was carried out on “Qiangguang-I” accelerator. The transient current of iron plate generated by pulsed gamma rays was measured and analysed, and the relationship between the amplitude of pulse current and the dose rate of gamma rays was obtained. The results show that the current response sensitivity of the iron plate is about 5.7×10-7(A/m2)/(Gy/s) when the gamma rays with the energy of 0.8 MeV irradiate the iron plate. The charge deposition rate in the iron plate can be obtained by Monte Carlo simulation, and then it can be converted to gamma ray induced current of the metal component irradiated by gamma rays.

2011 ◽  
Vol 679-680 ◽  
pp. 362-365 ◽  
Author(s):  
Takeshi Ohshima ◽  
Naoya Iwamoto ◽  
Shinobu Onoda ◽  
Takahiro Makino ◽  
Shinji Nozaki ◽  
...  

Charge induced in 6H-SiC nMOS capacitors by 15 MeV oxygen ion microbeams was measured using Transient Ion Beam Induced Current (TIBIC) before and after gamma-ray irradiations. The peak amplitude of TIBIC signals decreases and the fall time increases with increasing number of incident ions. The decrease in the TIBIC peak eventually saturated. The TIBIC signal can be refreshed to its original shape by applying a positive bias of + 1V to gate oxide. Small decrease in both the peak amplitude of TIBIC signal and collected charge was observed due to gamma-ray irradiation.


Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 111 ◽  
Author(s):  
Jin-Oh Jeong ◽  
Jong-Seok Park ◽  
Young-Ah Kim ◽  
Su-Jin Yang ◽  
Sung-In Jeong ◽  
...  

Conducting polymer (CP)-based hydrogels exhibit the behaviors of bending or contraction/relaxation due to electrical stimulation. They are similar in some ways to biological organs and have advantages regarding manipulation and miniaturization. Thus, these hydrogels have attracted considerable interest for biomedical applications. In this study, we prepared PPy/PVP hydrogel with different concentrations and content through polymerization and cross-linking induced by gamma-ray irradiation at 25 kGy to optimize the mechanical properties of the resulting PPy/PVP hydrogel. Optimization of the PPy/PVP hydrogel was confirmed by characterization using scanning electron microscopy, gel fraction, swelling ratio, and Fourier transform infrared spectroscopy. In addition, we assessed live-cell viability using live/dead assay and CCK-8 assay, and found good cell viability regardless of the concentration and content of Py/pTS. The conductivity of PPy/PVP hydrogel was at least 13 mS/cm. The mechanical properties of PPy/PVP hydrogel are important factors in their application for biomaterials. It was found that 0.15PPy/PVP20 (51.96 ± 6.12 kPa) exhibited better compressive strength than the other samples for use in CP-based hydrogels. Therefore, it was concluded that gamma rays can be used to optimize PPy/PVP hydrogel and that biomedical applications of CP-based hydrogels will be possible.


2008 ◽  
Vol 600-603 ◽  
pp. 707-710
Author(s):  
Shigeomi Hishiki ◽  
Naoya Iwamoto ◽  
Takeshi Ohshima ◽  
Hisayoshi Itoh ◽  
Kazu Kojima ◽  
...  

The effect of the fabrication process of n-channel 6H-SiC MOSFETs on their radiation resistance is investigated. MOSFETs that post implantation annealing for source and drain was carried out with carbon coating on the sample surface are compared to MOSFETs that post implantation annealing was carried out without carbon coating. The radiation resistance (gamma-rays) of the carbon-coated MOSFETs is higher than that of non-coated ones. The channel mobility for MOSFETs whose gate oxide was formed using pyrogenic or dry oxidation process dose not change by gamma-ray irradiation below 1x105 Gy. The value of channel mobility slightly increases with increasing dose above 1x105 Gy. No significant increase in irradiation induced interface traps is observed.


2019 ◽  
Vol 630 ◽  
pp. A56 ◽  
Author(s):  
V. M. Patiño-Álvarez ◽  
S. A. Dzib ◽  
A. Lobanov ◽  
V. Chavushyan

We investigate the relationship between the variable gamma-ray emission and jet properties in the blazar 3C 279 by combining the Fermi-LAT data spanning a period of eight years and concurrent radio measurements made at multiple epochs with VLBA at 15 and 43 GHz within the MOJAVE and VLBA-BU monitoring programmes. The aim of this paper is to compare the flux variability of the different components found in the VLBA observations, to the variability in the gamma-rays. This analysis helps us to investigate whether any of the jet components can be associated with the gamma-ray variability. Through Spearman rank correlation we found that the gamma-ray variability is correlated with a particular region (feature B in the MOJAVE images) downstream from the observed base (core) of the jet. This jet component is therefore a likely location where an important fraction of the variable gamma-ray emission is produced. We also calculated the average proper motion of the component with respect to the VLBA core and found that it moves at an apparent superluminal velocity of (3.70 ± 0.35)c, implying that one of the gamma-ray emission zones is not stationary. This jet component is also found between 6.86 mas and 8.68 mas, which translates to a distance from the radio core of at least 42 pc.


Pastura ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 1
Author(s):  
Prihantoro, I. ◽  
Anandia, A. ◽  
Aryanto, A. T. ◽  
Setiana, M. A. ◽  
Karti, P. D. M. H.

Alfalfa (Medicago sativa L.) a high nutritious and palatability legume for ruminant. Constrain of alfalfa availability in Indonesia are due to the plant adaptability in tropical environment. Aim of the study was to measure the adaptation level of alfalfa that irradiated with gamma rays on a field scale. The study consisted of four types of plant sources, mutation plants with different gamma ray levels (0Gy, 200Gy, 300Gy and 400Gy). Plant tillers was analyzed with a complete randomized design with 3 replications, 20 plants per replication. Growth capability, leaf color, flowering time and pest attack level were analyzed descriptively. The results showed that alfalfa irradiated with 300 Gy significantly (p<0.05) produced highest tillers. Irradiated 300 Gy plant gave better result on growth capability, flowering capability, and number of not attack plant from pests. The higher level of gamma ray irradiation showed the changed in leaf color levels from dark green to light green. Keywords: alfalfa (Medicago sativa L.), mutation, gamma ray irradiation, field scale


1994 ◽  
Vol 142 ◽  
pp. 899-903
Author(s):  
Matthew G. Baring

AbstractThe principal discovery of the ComptonGamma-Ray Observatory(GRO) concerning gamma-ray bursts is that these sources are isotropic but with a comparative deficiency of fainter sources, suggesting that they are probably cosmological in origin. If they are at such large distances from Earth then they are extremely luminous and compact. A consequence of this is that two-photon pair production attenuation of the gamma-ray continuum cannot be avoided unless the source radiation is substantially beamed. Most sources do not display gamma-ray turnovers although a few GRB detected byGROexhibit distinct spectral breaks in the MeV range. A derivation of the relationship defining of the degree of beaming in burst sources with spectral breaks due toγ-γattenuation, as a function of source spectral index and break energy, is presented. It is found that sources at distances of ~1 Gpc must typically be beamed with bulk Lorentz factors of around 103-104, indicating powerful bulk acceleration in bursts, although these Lorentz factors are reduced markedly for steep source spectra. Since the source spectra are not strongly Comptonized, such beaming will blueshift the γ-γ attenuation breaks to energies much higher than 1 MeV; an absolute lower bound to the source bulk Lorentz factor is determined from this additional constraint. This blueshifting suggests that those sources with MeV breaks may not be cosmological, or that their breaks are produced by a mechanism that dominates γ-γ attenuation at these energies.Subject headings:gamma-rays: bursts — radiation mechanisms: nonthermal


2016 ◽  
Vol 43 (3) ◽  
pp. 235
Author(s):  
Arrin Rosmala ◽  
Nurul Khumaida ◽  
Dewi Sukma

<p>ABSTRACT</p><p>Handeuleum (Graptophyllum pictum L.Griff) is a medicinal plant widely used as a traditional medicine due to its benefecial content. Therefore, it should be developed as one of the leading Indonesian medicinal plants. The purpose of this research was to study the effect of gamma ray irradiation on morphological alteration and growth of Handeuleum accession from Bogor. The doses of gamma rays were 0, 15, 30, 45, 60, 75, 90, and 105 Gy. The results of the research showed that gamma-ray irradiation induced morphological changes and influences the growth of Handeuleum. Irradiation dose at rate of 105 Gy produced new leaf morphology in Handeuleum, namely cordate. Doses of 60, 75, 90, and 105 Gy produce stunted plants with stiff and yellowish-green leaves. The dose of 45 Gy produced relative green color index which was higher than the control plants.</p><p>Keywords: handeuleum, gamma irradiations</p>


2021 ◽  
Vol 12 ◽  
Author(s):  
Sang Woo Lee ◽  
Yu-Jeong Kwon ◽  
Inwoo Baek ◽  
Hong-Il Choi ◽  
Joon-Woo Ahn ◽  
...  

Protons may have contributed to the evolution of plants as a major component of cosmic-rays and also have been used for mutagenesis in plants. Although the mutagenic effect of protons has been well-characterized in animals, no comprehensive phenotypic and genomic analyses has been reported in plants. Here, we investigated the phenotypes and whole genome sequences of Arabidopsis M2 lines derived by irradiation with proton beams and gamma-rays, to determine unique characteristics of proton beams in mutagenesis. We found that mutation frequency was dependent on the irradiation doses of both proton beams and gamma-rays. On the basis of the relationship between survival and mutation rates, we hypothesized that there may be a mutation rate threshold for survived individuals after irradiation. There were no significant differences between the total mutation rates in groups derived using proton beam or gamma-ray irradiation at doses that had similar impacts on survival rate. However, proton beam irradiation resulted in a broader mutant phenotype spectrum than gamma-ray irradiation, and proton beams generated more DNA structural variations (SVs) than gamma-rays. The most frequent SV was inversion. Most of the inversion junctions contained sequences with microhomology and were associated with the deletion of only a few nucleotides, which implies that preferential use of microhomology in non-homologous end joining was likely to be responsible for the SVs. These results show that protons, as particles with low linear energy transfer (LET), have unique characteristics in mutagenesis that partially overlap with those of low-LET gamma-rays and high-LET heavy ions in different respects.


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