Computer simulation of (n, p) modifications in silicon nitride (Si3N4) nanoparticles

2020 ◽  
Vol 34 (32) ◽  
pp. 2050318
Author(s):  
T. G. Naghiyev
Keyword(s):  
Computer Simulation ◽  
Silicon Nitride ◽  
Stable Isotope ◽  
Cross Section ◽  
Cross Sections ◽  
Effective Cross Section

(n, p) transmutations in the silicon nitride (Si3N4) nanoparticles by the neutrons at different energies have been studied by computer simulation. The transmutations by neutrons in the nanomaterial were separately investigated for silicon and nitrogen atoms in the Si3N4 particles. Since the effective cross-section of the possible probability of transmutation is different in the various types of silicon and nitrogen atoms, the modeling was performed separately for each stable isotope. The spectra of the effective cross-sections of the (n, p) transmutations for silicon and nitrogen atoms have been studied in relation to each other.

An investigation of silicon nitride (Si3N4) nanoparticles interaction with neutrons

2020 ◽  
pp. 2150104
Author(s):  
T. G. Naghiyev
Keyword(s):  
Silicon Nitride ◽  
Stable Isotope ◽  
Computer Modeling ◽  
Cross Section ◽  
Effective Cross Section ◽  
Different Types

The absorption of neutrons in nano-[Formula: see text] particles at different energies has been studied by computer modeling. The investigation was carried out separately for the silicon and nitrogen atoms that contain [Formula: see text] nanoparticles. Since the effective cross-section of absorption in different types of isotopes of silicon and nitrogen atoms is different, the modeling was performed separately for each stable isotope. Simultaneously, the effective cross-section spectra of neutrons for silicon and nitrogen atoms were studied.

Effect of Electrostatic Interactions on Effective Cross-Sections for Collision of Small Particles With Neutral Molecules

1993 ◽  
Vol 46 (1) ◽  
pp. 13 ◽  
Author(s):  
LF Phillips
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Atmospheric Aerosols ◽  
Electrostatic Interactions ◽  
Interstellar Dust ◽  
Effective Cross Section ◽  
Classical Trajectory ◽  
Polar Molecules ◽  
Interstellar Dust Grains ◽  
Geometrical Cross Section

Quasi-classical trajectory calculations have been used to calculate effective collision cross-sections for polar and non-polar molecules with charged and neutral conducting spheres of radius 0.001-0.1 μm over the temperature range 10-400 K. In general the effective cross-section is much larger than the geometrical cross-section, especially for small, highly charged, particles colliding with highly polar molecules at low temperatures. The results may have a bearing on the growth of atmospheric aerosols and of interstellar dust grains.

Neutron-alpha reactions in nano α-Si3N4 particles by neutrons

2021 ◽  
Vol 36 (24) ◽  
pp. 2150181
Author(s):  
T. G. Naghiyev
Keyword(s):  
Stable Isotope ◽  
Computer Modeling ◽  
Cross Section ◽  
Effective Cross Section ◽  
Different Types

Computer modeling was applied to the study of [Formula: see text] transmutations in [Formula: see text] nanoparticles under the influence of neutrons at different energies. The modeling was separately performed for each Si and N atoms in the [Formula: see text] nanoparticles and the effect of neutrons on transmutations was investigated. The simulations were conducted individually for each stable isotope due to different effective cross-section of the probability of transmutation in the different types of isotopes of silicon and nitrogen atoms. Effective cross-section spectra of [Formula: see text] transmutation in Si and N atoms were comparatively studied.

EXCITATION CURVES FOR THE REACTIONS Fe56(n, p)Mn56 AND Co59(n, α)Mn56

1964 ◽  
Vol 42 (6) ◽  
pp. 1030-1036 ◽  
Author(s):  
D. C. Santry ◽  
J. P. Butler
Keyword(s):  
Cross Section ◽  
Neutron Spectrum ◽  
Neutron Energy ◽  
Cross Sections ◽  
Effective Cross Section ◽  
Fission Neutron ◽  
Reaction Cross ◽  
Fission Neutron Spectrum ◽  
Threshold Energies ◽  
Reaction Cross Sections

Excitation curves for the reactions Fe56(n, p)Mn56 and Co59(n, α)Mn56 have been measured by the activation method from near threshold energies to 20.3 Mev. The measurements are relative to the known cross section for the S32(n, p)P32 reaction. Cross sections for both reactions increase smoothly with neutron energy and reach maximum values of 119 ± 4 mb for the Fe56(n, p) reaction at 13.6 Mev and 30.0 ± 0.9 mb for the Co59(n, α) reaction at 14.5 Mev. Above 15 Mev both cross sections decrease with neutron energy. From the excitation curves effective cross-section values for a fission-neutron spectrum have been calculated as 1.04 ± 0.05 mb for the (n, p) reaction and 0.140 ± 0.007 mb for the (n, α) reaction.

Cross Section Measurements for the 103Rh(n,n′)103Rhm Reaction from 0.122 to 14.74 MeV

1974 ◽  
Vol 52 (15) ◽  
pp. 1421-1428 ◽  
Author(s):  
D. C. Santry ◽  
J. P. Butler
Keyword(s):  
Neutron Flux ◽  
Cross Section ◽  
Neutron Spectrum ◽  
Cross Sections ◽  
Energy Levels ◽  
Effective Cross Section ◽  
Fission Neutron ◽  
Activation Method ◽  
Excitation Curve ◽  
Fission Neutron Spectrum

Cross sections for the production of 103Rhm were measured by the activation method. At energies below 5.3 MeV the neutron flux was measured with a calibrated neutron long counter, while at higher energies, measurements were made relative to the known cross section for the 32S(n,p)32P reaction. The shape of the Rh excitation curve is discussed in terms of known energy levels in 103Rh. An effective cross section for a 235U fission neutron spectrum calculated from the measured excitation curve is 724 ± 43 mb.

scholarly journals DPS mechanism for associated $$c\bar{c} b\bar{b}$$ production in AA UPCs

2020 ◽  
Vol 80 (8) ◽  
Author(s):  
Edgar Huayra ◽  
Emmanuel G. de Oliveira ◽  
Roman Pasechnik
Keyword(s):  
Production Process ◽  
Cross Section ◽  
Photon Energy ◽  
Cross Sections ◽  
Effective Cross Section ◽  
Double Parton Scattering ◽  
Quark Pairs ◽  
Numerical Predictions ◽  
Energy Dependent ◽  
Parton Scattering

Abstract We discuss the associated $$c\bar{c}$$cc¯ and $$b\bar{b}$$bb¯ quark pairs production in the double-parton scattering (DPS) process in ultraperipheral (UPCs) AA collisions. We derive an analogue of the inclusive DPS pocket formula and the photon-energy dependent effective cross section considering an overlap between the hard SPS scatterings. We provide numerical predictions for the DPS cross sections for the $$c\bar{c}b\bar{b}$$cc¯bb¯ production process at the typical energies of AA UPCs at the LHC and FCC colliders and also characterize the A dependence of the total UPC DPS cross section.

EXCITATION CURVES FOR THE REACTIONS Al27(n, α)Na24 AND Mg24(n, p)Na24

1963 ◽  
Vol 41 (2) ◽  
pp. 372-383 ◽  
Author(s):  
J. P. Butler ◽  
D. C. Santry
Keyword(s):  
Cross Section ◽  
Neutron Spectrum ◽  
Cross Sections ◽  
Effective Cross Section ◽  
Fission Neutron ◽  
Activation Method ◽  
Graaff Accelerator ◽  
Fission Neutron Spectrum ◽  
Van De Graaff ◽  
Threshold Energies

Excitation curves for the reactions Al27(n, α)Na24 and Mg24(n, p)Na24 have been measured by the activation method from near threshold energies to 20.3 Mev. The measurements are relative to the known cross section for the reaction S32(n, p)P32. Monoenergetic neutrons were obtained from the D(d, n)He3, T(d, n)He4, and the T(p, n)He3 reactions employing a Tandem Van de Graaff accelerator or 125-kev accelerator. Cross sections for both reactions rise above the minimum detectable value of 0.02 mb near 5 Mev and reach maximum values of 126 mb for the Al(n, α)Na24 reaction and 205 mb for the Mg24(n, p)Na24 reaction at 13.5 Mev. Above this energy both cross sections decrease. From the excitation curves effective cross-section values for a fission-neutron spectrum have been calculated as 0.61 ± 0.03 mb for the (n, α) reaction and 1.34 ± 0.07 mb for the (n, p) reaction.

Cross sections for the 93Nb(n,2n)92mNb reaction

1990 ◽  
Vol 68 (7-8) ◽  
pp. 582-586 ◽  
Author(s):  
D. C. Santry ◽  
R. D. Werner
Keyword(s):  
Cross Section ◽  
Neutron Spectrum ◽  
Cross Sections ◽  
Threshold Energy ◽  
Effective Cross Section ◽  
Fission Neutron ◽  
Transfer Standard ◽  
Fission Neutron Spectrum ◽  
Maximum Value ◽  
The Cross

The cross section of the 93Nb(n,2n)92mNb reaction has been studied by use of the activation method from the threshold energy of 8.8–19.8 MeV. Measurements are relative to the known cross-section values for the reactions H(n,n)H, 32S(n,p)32p, and 27Al(n,α)24Na. The cross-section value increases smoothly with energy and reaches a maximum value of 444 ± 18 mb at about 14.5 MeV then decreases to values of 293 ± 14 mb at 19.8 MeV. An effective cross-section value for a fission neutron spectrum calculated from the results is 0.321 ± 0.019 mb. The activation of Nb as a transfer standard for 14 MeV neutrons is discussed.

MEASUREMENT OF RADIATIVE CAPTURE RESONANCE INTEGRALS IN A THERMAL REACTOR SPECTRUM, AND THE THERMAL CROSS SECTION OF Pu-240

1960 ◽  
Vol 38 (1) ◽  
pp. 57-77 ◽  
Author(s):  
W. H. Walker ◽  
C. H. Westcott ◽  
T. K. Alexander
Keyword(s):  
Cross Section ◽  
Neutron Beam ◽  
Cross Sections ◽  
Radiative Capture ◽  
Effective Cross Section ◽  
Mean Value ◽  
Resonance Integral ◽  
Thermal Reactor ◽  
Thermal Cross Section ◽  
Radiative Neutron Capture

An apparatus is described which detects γ-rays emitted by a thin target placed in a well-denned neutron beam. It has been used to determine the Cd ratios of Au and Pu-240, from which the ratio of the resonance integral to the 2200 m/s cross section for radiative neutron capture in Pu-240 has been deduced, using Au as a reference standard. Using this ratio and previously measured values of the resonance integral of Pu-240 and its effective cross section in two positions in the NRX reactor, three separate estimates of the 2200 m/s cross section of Pu-240 have been made. The mean value is 270 ± 17 barns.In an auxiliary experiment to indicate the shape of the epithermal spectrum of the neutron beam, the activation Cd ratios of Mn and In were compared with that of Au. These results, combined with the known 2200 m/s capture cross sections of these nuclides, yield new values of the radiative capture resonance integrals for both Mn and In.

EXCITATION CURVES FOR THE (n, 2n), (n, p), AND (n, nα) REACTIONS OF 65Cu

1966 ◽  
Vol 44 (5) ◽  
pp. 1183-1193 ◽  
Author(s):  
D. C. Santry ◽  
J. P. Butler
Keyword(s):  
Cross Section ◽  
Neutron Spectrum ◽  
Cross Sections ◽  
Effective Cross Section ◽  
Fission Neutron ◽  
A Value ◽  
Fission Neutron Spectrum ◽  
Maximum Value ◽  
Section Curve ◽  
Threshold Energies

Cross sections for the reactions 65Cu (n, 2n)64Cu, 65Cu(n, p)65Ni, and 65Cu(n, nα)61Co have been measured by the activation method from threshold energies up to 20.2 MeV. The measurements are relative to the known cross section for the reaction 32S(n, p)32P. The (n, 2n) cross-section curve increases smoothly with energy and reaches a maximum value of 1 085 ± 60 mb at about 18 MeV. The (n, p) reaction reaches a maximum value of 21.7 ± 1.2 mb at 13.9 MeV. The (n, nα) reaction has a minimum detectable value of 0.3 ± 0.1 mb near 14 MeV and increases to a value of 18.9 ± 0.9 mb at 19.8 MeV. Effective cross-section values for a fission-neutron spectrum calculated from these results are 0.251 ± 0.018 mb for the (n, 2n) reaction and 0.523 ± 0.030 mb for the (n, p) reaction.

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