Studies of the behavior of a reactor neutron beam at the sample position of a diffractometer using silicon monochromators

The neutron beam facility at NCSR “Demokritos” is driven by a 5.5 MV tandem T11/25 Van De Graff accelerator that provides continuous, high intensity ion beams. Depending on the neutron production reaction, different energy regions of neutron beams are available. Neutron fields with well defined energies are produced by means of nuclear reactions such as: 7Li(p,n)7Be, 3H(p,n)3He, 2H(d,n)3He and 3H(d,n)4He, delivering neutrons up to the energy of ~28 MeV. In order to fully characterize the neutron beam at NCSR “Demokritos”, in the framework of the present work, the CONY C++ computer code has been developed. The implementation of the code for the 7Li(p,n)7Be and 3H(d,n)4He reactions is discussed. The method of calculation of differential neutron yields by thin and thick targets is described. Specifically, for the reaction 7Li(p,n)7Be the mathematical singularity at near threshold energies is discussed along with the method that was used as to overcome this issue. Finally, the results of the code including the double differential neutron yields, the neutron beam energy distribution at the sample position and the total neutron yields have been compared with experimental data as well as with the results of the NeuSDesc software (JRC-IRMM: Neutron Source Description).

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Combined reactor neutron beam and 60Co γ-ray radiation effects on CMOS APS image sensors

AIP Advances ◽

10.1063/1.4913373 ◽

2015 ◽

Vol 5 (2) ◽

pp. 027128 ◽

Cited By ~ 3

Author(s):

Zujun Wang ◽

Wei Chen ◽

Jiangkun Sheng ◽

Yan Liu ◽

Zhigang Xiao ◽

...

Keyword(s):

Neutron Beam ◽

Radiation Effects ◽

Image Sensors ◽

Reactor Neutron ◽

Γ Ray

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Determination of the Neutron Beam Spatial Profile at n_TOF EAR-2 using the CR-39 Track Detectors

HNPS Proceedings ◽

10.12681/hnps.1903 ◽

2019 ◽

Vol 23 ◽

pp. 28

Author(s):

Z. Eleme ◽

M. Alexandropoulou ◽

A. Georgiadou ◽

K. G. Ioannides ◽

M. Kokkoris ◽

...

Keyword(s):

Neutron Beam ◽

Optical Microscope ◽

Fast Neutrons ◽

Hydrogen Atoms ◽

Spatial Profile ◽

Naoh Solution ◽

Sample Position ◽

Cr 39 Detectors

Within the present work the neutron beam spatial profile was determined at the sample position in EAR-2 at the n_TOF facility at CERN. The CR-39 detectors were coupled with a 2mm PE foil serving as neutron-to-proton converter. Two irradiations were performed in the 10x5 cm surface of CR-39 detectors. Proton tracks were revealed in the CR-39 detectors resulting from the elastic scattering of fast neutrons on the hydrogen atoms in the PE converter. Afterwards, the CR-39 detectors were chemically etched in aqueous NaOH solution and latent tracks were considerably enlarged to become visible under an optical microscope. After the scanning of the detectors surface, the acquired images were analyzed using the ImageJ program. In the present work, the experimental setup and procedure will be presented along with the results concerning the characterization of the neutron beam spatial profile at the sample position in the n_TOF EAR-2.

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