Impact of reactor neutron spectrum on measured spectrum averaged cross sections

Košťál, Michal; Losa, Evžen; Simakov, S.P.; Schulc, Martin; Šimon, Jan; Rypar, Vojtěch; Mareček, Martin; Uhlíř, Jan; Czakoj, Tomáš; Trkov, A.; Capote, R.

doi:10.1016/j.anucene.2022.109418

Cited by 5 publications

(5 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It was shown experimentally that the neutron spectrum in the used neutron field is identical with 235 U(n th , f) prompt fission neutron spectrum (PFNS) in the 6-14 MeV region , while calculation confirmed this in the 6-20 MeV region (Kostal et al 2022b). However, due to the design of the driver reference core and variations in water level or even vertical positioning of the cylindrical volume containing samples, shifts in neutron spectrum have been observed among three consecutive irradiation sets.…”

Section: Irradiation Setupmentioning

confidence: 77%

“…It is interesting to note that a similar dominance effect of photo-over neutron-induced reactions on gold was observed in the VR-1 reactor. In this environment, the effect reached ≈ 50 % outside the fission core, where the neutron flux decreased stronger than γ-flux, see (Kostal et al 2022b). Inside the VR-1 core, fraction of (γ,p)/(n,2n) on 197 Au was estimated to be 0.61 %, a value comparable to that obtained inside LR-0.…”

Section: Correction To Sections 235 U(n Th F) Pfnsmentioning

confidence: 86%

“…It is worth noting that the difference between the shapes of the VR-1 reactor (another zero power light water moderated reactor, more details are in Kostal et al 2021) neutron spectrum and 235 U(n th ,f) fission neutron spectrum was found to be significantly larger, which was explained by the greater thickness of cooling water between the uranium fuel rods and foil irradiation point (Kostal et al 2022b 27 Al and 238 U (note the downward direction). Abscissa: The median n-SACS energies E50% for the studied reactions are indicated by vertical bars with the reaction shorthand labels adopted in IRDFF (Trkov et al, 2020).…”

Section: Neutron and Gamma Fluxesmentioning

confidence: 95%

“…The prominent discrete γ-lines observed between 7 and 10 MeV are primary γ-ray transitions to the ground states from thermal neutron capture on the iron isotopes 56 Fe, 54 Fe, and 57 Fe. At higher energies, from 10 up to 20 MeV, the relatively smooth energy spectrum of γ-rays is mostly stem from caused by neutron induced fission of U isotopes and high energy neutron inelastic scattering (the detailed analysis of these issues but for the case of the VR-1 reactor is given in (Kostal et al 2022b).…”

Section: Correction To Sections 235 U(n Th F) Pfnsmentioning

confidence: 99%

See 3 more Smart Citations

Special Issue: Research Center Řež: Nuclear-Engineering Activities in 2020

Košťál¹,

Schulc²

2021

Journal of Nuclear Engineering and Radiation Science

View full text Add to dashboard Cite

This special issue is dedicated primarily to research performed in the Research Centre Rež (CVR, Centrum výzkumu Rež Fig. 1) during the Research for SUSEN (R4S) project, which is the follow-up of the (SUSEN) project, that was successfully completed at the end of 2020. Research Centre Rež is a research organization founded in 2002. It is a member of the UJV Group, and it is focused on the pre-commercial research in power-generation technologies, predominantly, but not exclusively, in the nuclear field. The R4S project comprised many topics, including the research and development of new technologies for current and future generations of nuclear reactor systems and nuclear fusion reactors. It was carried out within the CVR, in close partnership with the University of West Bohemia, and was funded by the Ministry of Education, Youth and Sports of the Czech Republic.

show abstract

Section: Irradiation Setupmentioning

confidence: 77%

Section: Correction To Sections 235 U(n Th F) Pfnsmentioning

confidence: 86%

Section: Neutron and Gamma Fluxesmentioning

confidence: 95%

Section: Correction To Sections 235 U(n Th F) Pfnsmentioning

confidence: 99%

See 2 more Smart Citations

Special Issue: Research Center Řež: Nuclear-Engineering Activities in 2020

Košťál¹,

Schulc²

2021

Journal of Nuclear Engineering and Radiation Science

View full text Add to dashboard Cite

show abstract

“…[1,5] Fast neutrons from the reference field of the LR-0 reactor were used for uniform lifetime reduction. [6] Diodes were irradiated at room temperature with fluences ranging from 5.6 Â 10 10 to 5.9 Â 10 12 cm À2 (1 MeV SiC equivalent). The local lifetime reduction was realized by irradiation with 800 keV or 1 MeV protons using the 3 MeV tandetron accelerator.…”

Section: Methodsmentioning

confidence: 99%

Radiation Defects and Carrier Lifetime in 4H‐SiC Bipolar Devices

Hazdra

Smrkovský

Popelka

2021

Physica Status Solidi (a)

View full text Add to dashboard Cite

The effect of radiation damage on the minority carrier lifetime in the 4 H‐SiC epilayers forming the n‐base of the power p–i–n diodes is presented. Irradiation with fast neutrons and MeV protons is used for uniform and local lifetime reduction. Deep‐level transient spectroscopy in combination with open‐circuit voltage decay measurement shows that the carrier lifetime is reduced by increased carrier recombination on Z1/Z2, EH3, and possibly RD4 levels. The lifetime degrades swiftly and the ON‐state carrier modulation capability of high‐voltage devices can be easily lost already at very low fluences. The results further show that the proton irradiation provides an excellent tool for local lifetime tailoring. The carrier lifetime can be easily set by proton fluence and localized by proton energy. The proper local lifetime reduction speeds up diode recovery without an undesirable increase in the forward voltage drop. However, attention must be taken to properly locate the damage maximum so as not to increase device leakage.

show abstract