JOPSS - Search Results

Journal Articles

Characterization of bremsstrahlung and -rays of fuel debris

Matsumura, Taichi; Okumura, Keisuke; Fujita, Manabu*; Sakamoto, Masahiro; Terashima, Kenichi; Riyana, E. S.

Radiation Physics and Chemistry, 199, p.110298_1 - 110298_8, 2022/10

https://doi.org/10.1016/j.radphyschem.2022.110298

Times Cited Count：1 Percentile：31.61(Chemistry, Physical)

Journal Articles

Yields of strand breaks and base lesions induced by soft X-rays in plasmid DNA

Yokoya, Akinari; Fujii, Kentaro; Ushigome, Takeshi; Shikazono, Naoya; Urushibara, Ayumi; Watanabe, Ritsuko

Radiation Protection Dosimetry, 122(1-4), p.86 - 88, 2006/12

https://doi.org/10.1093/rpd/ncl408

Times Cited Count：11 Percentile：60.27(Environmental Sciences)

We have studied yields of DNA damages induced by soft X-rays obtained from a conventional soft X-ray machine in a LET region between -rays and ultrasoft X-rays. Practically soft X-rays with a broad energy spectrum emitted from a target of heavy metal, such as tungsten, have been widely used not only for radiobiological experiments but also for medical application such as mammography. Radiation weighting factors for these soft X-rays have been assigned to be 1 by ICRP. However, the fraction of a large number of low energy photons in the spectrum (below several tens keV) provided by bremsstrahlung is expected to be more effective for DNA damage induction than -rays since low energy photo- and Auger electrons predominantly ejected in consequence of a photoelectric effect can produce dense clusters of ionization/excitation on DNA molecules. We have examined the yield of DNA strand breaks induced by white soft X-rays (150 kVp, tungsten target). Yields of base lesions revealed by base excision repair enzymes will be also presented.

Journal Articles

Role of bremsstrahlung radiation in limiting the energy of runaway electrons in Tokamaks

Bakhtiari, M.; Kramer, G. J.*; Takechi, Manabu; Tamai, Hiroshi; Miura, Yukitoshi; Kusama, Yoshinori; Kamada, Yutaka

Physical Review Letters, 94(21), p.215003_1 - 215003_4, 2005/06

https://doi.org/10.1103/PhysRevLett.94.215003

Times Cited Count：45 Percentile：82.81(Physics, Multidisciplinary)

Bremsstrahlung radiation of runaway electrons is found to be an energy limit for runaway electrons in tokamaks. The minimum and maximum energy of runaway electron beams is shown to be limited by collisions and Bremsstrahlung radiation, respectively. It is also found that a massive injection of a high-Z gas such as Xenon can terminate a disruption-generated runaway current before the runaway electrons hit the walls.

Journal Articles

Measurement of depth distributions of $^{3}$ H and $^{14}$ C induced in concrete shielding of an electron accelerator facility

Endo, Akira; Harada, Yasunori; Kawasaki, Katsuya; Kikuchi, Masamitsu

Applied Radiation and Isotopes, 60(6), p.955 - 958, 2004/06

https://doi.org/10.1016/j.apradiso.2004.01.010

Times Cited Count：7 Percentile：45.11(Chemistry, Inorganic & Nuclear)

no abstracts in English

Journal Articles

Applicability study on existing dosimetry systems to high-power Bremsstrahlung irradiation

Mehta, K.*; Kojima, Takuji; Sunaga, Hiromi

Radiation Physics and Chemistry, 68(6), p.959 - 962, 2003/12

https://doi.org/10.1016/j.radphyschem.2003.08.007

Times Cited Count：3 Percentile：25.79(Chemistry, Physical)

Applicability of the existing dosimetry systems to high-power Bremsstrahlung irradiation was investigated through a dose intercomparison study, where several dosimeters were irradiated in the dose range 4-12 kGy in identical polyethylene phantoms in a Bremsstrahlung beam obtained from a 5-MeV electron accelerator. Included in the study were alanine dosimeters molded by three different binders, three types of liquid dosimeters:ceric-cerous, dichromate and ethanol-chlorobenzen (ECB), and glutamine powder. The dosimeter responses for Bremsstrahlung radiation were analyzed at the issuing laboratories, and the dose values determined using calibration based on cobalt-60 -ray irradiation. Dose values for all the three dose levels for all dosimetry systems were in good agreement of better than 3%. The results of the study demonstrate that these existing dosimetry systems have a potential for application to high-power Bremsstrahlung irradiation.

JAEA Reports

Inferring $Z_{eff}$ spatial profile from background light in incoherent Thomson scattering diagnostic

Naito, Osamu; Hatae, Takaki

JAERI-Research 2002-033, 9 Pages, 2003/03

JAERI-Research-2002-033.pdf:0.46MB

A simulation study on the feasibility of inferring spatial $Z_{eff}$ profile along with electron temperature and density in Thomson scattering diagnostic is presented. The background signal, which is usually discarded after subtracted from the Thomson scattered signal, is used in the reconstruction procedure. If the contribution from line radiation to the background signal is by one order of magnitude smaller than that from bremsstrahlung, a fairly accurate $Z_{eff}$ profile can be reconstructed.

Journal Articles

Photofission of $^{209}$ Bi at intermediate energies

Haba, Hiromitsu; Kasaoka, Makoto*; Igarashi, Manabu*; Washiyama, Koshin*; Matsumura, Hiroshi*; Oura, Yasuji*; Shibata, Seiichi*; Sakamoto, Ko*; Furukawa, Michiaki*; Fujiwara, Ichiro*

Radiochimica Acta, 90(7), p.371 - 382, 2002/08

https://doi.org/10.1524/ract.2002.90.7_2002.371

Times Cited Count：2 Percentile：17.03(Chemistry, Inorganic & Nuclear)

The reaction yields of 63 radionuclides with the mass number A = 56-135 produced in the photofission of $^{209}$ Bi by bremsstrahlung of end-point energies (E $_{0}$ ) from 450 to 1100 MeV have been measured using a catcher foil technique. The charge distribution was well reproduced by a Gaussian function with the most probable charge (Z $_{p}$ ) expressed by Z $_{p}$ = RA + S, and with the A-independent FWHME $_{CD}$ . The charge distribution parameters R, S and FWHM $_{CD}$ were independent of E $_{0}$ above 600 MeV. The weighted mean values at E $_{0}$ 600 MeV were R = 0.421 0.001, S = 0.6 0.1 and FWHM $_{CD}$ = 2.1 0.1 charge unit (c.u.). Based on the charge distribution parameters, the symmetric mass yield distributions with the most probable mass A $_{p}$ of 96 1 mass unit (m.u.) and the width FWHM $_{MD}$ of 33 1 m.u. were also obtained. The characteristics of the charge and mass yield distributions are discussed by referring to those for $^{197}$ Au based on the results of calculations using PICA3/GEM.