Research of influence of detector load at cross-section determination after transmission method by the filtered reactor beams

2011 ◽  
Vol 30 (0) ◽  
pp. 135-141
Author(s):  
О. О. Грицай ◽  
С. П. Волковецький ◽  
В. А. Лібман
Keyword(s):  
Cross Section ◽  
Transmission Method

scholarly journals Resonance phenomena in the interaction of fast neutrons with beryllium and aluminium

1947 ◽  
Vol 192 (1028) ◽  
pp. 114-127 ◽  
Keyword(s):  
Energy Level ◽  
Cross Section ◽  
Neutron Energy ◽  
Cross Sections ◽  
Accurate Determination ◽  
Fast Neutrons ◽  
Transmission Method ◽  
The Cross ◽  
Scattering Cross Sections

The total scattering cross-sections of beryllium and aluminium have been measured by a transmission method for neutrons of energies between 0∙35 and 0∙55 MeV and 1∙8 and 4∙0 MeV. Resonances have been found in the scattering by beryllium at a neutron energy of 2∙6 MeV and in the scattering by aluminium at neutron energies of 2∙4 and 2∙9 MeV. It has been shown that the cross-section for the reaction 9 Be ( n , α ) 6 He also has a resonance at 2∙6 MeV, and an accurate determination of the cross-section for this reaction has been made. A discussion is given of the properties of the energy level in 10 Be responsible for the resonances in the case of beryllium.

POSSIBLE EXOTIC STRUCTURE IN LIGHT PROTON-RICH NUCLEI

2003 ◽  
Vol 18 (02n06) ◽  
pp. 151-161 ◽  
Author(s):  
H. Y. ZHANG ◽  
W. Q. SHEN ◽  
Y. G. MA ◽  
X. Z. CAI ◽  
D. Q. FANG ◽  
...  
Keyword(s):  
Cross Section ◽  
Reaction Cross Section ◽  
Reaction Cross ◽  
Drip Line ◽  
Projectile Fragmentation ◽  
Transmission Method ◽  
Carbon Target ◽  
Halo Structure ◽  
Intermediate Energies ◽  
Proton Halo

Radioactive ion beams were produced through the projectile fragmentation induced by 69MeV/nucleon 36 Ar primary beam on a 9 Be target. Measurements of reaction cross section (σR) for some proton-rich nuclei on carbon target at intermediate energies around 30MeV/nucleon have been performed on RIBLL of HIRFL by transmission method and transmission plus transportation method. The experimental σR values for 23Al and 27P are abnormally large compared with their neighboring nuclei and that of 17F has an enhancement compared with the neighboring isotopes. It suggests anomalously large matter root-mean-square radii and proton halo structure in 23 Al and 27 P . The experimental σR values and momentum distribution of fragmentation reaction product for 31 Cl , 32 Cl , 33 Cl , 28 S , 29 S were performed also on RIBLL by transmission and transportation method. These data are in analyzing. The calculation of relativistic density-dependent Hartree shows that the nuclei 23 Al , 27 P , 31 Cl may have proton-halo structure and 17F, 32Cl may have proton-skin structure. New experiment on the search for new nuclides 25 P and 26 S in proton drip line is also described. The significance of these measurements and possible proton halo and skin for light proton-rich nuclei has been discussed.

Evaluation of incoherent scattering intensity by transmission and sample thickness

2009 ◽  
Vol 42 (4) ◽  
pp. 621-628 ◽  
Author(s):  
Mitsuhiro Shibayama ◽  
Takuro Matsunaga ◽  
Michihiro Nagao
Keyword(s):  
Cross Section ◽  
Heavy Water ◽  
Small Angle Neutron Scattering ◽  
Unit Volume ◽  
Polymer Gels ◽  
Incoherent Scattering ◽  
Sample Thickness ◽  
Transmission Method ◽  
Aqueous Dispersions ◽  
Scattering Intensity

The H atom has a large incoherent scattering cross section and is a major source of incoherent scattering intensity, (dΣ/dΩ)inc, in small-angle neutron scattering. By taking account of multiple scattering from H atoms, a useful method (the transmission method orTmethod) is proposed for the estimation of (dΣ/dΩ)incfor various types of hydrogen-containing systems. The incoherent scattering intensity is calculated simply from the transmission,T, and the thickness of the sample,t,i.e.(dΣ/dΩ)inc≅ [exp(Σtott) − 1]/(4πt) = (1 −T)/(4πtT), where Σtot≡ −(lnT)/tis the macroscopic total cross section per unit volume. This method provides a reasonably accurate value of incoherent scattering intensity for various systems. The validity and the extent of applicability of theTmethod are examined for several samples, including light/heavy water mixtures, polymer gels and surfactant aqueous dispersions.

scholarly journals Measurement of Total Electronic Cross-Section, Total Atomic Cross-Section, Effective Atomic Numbers, Effective Electron Densities and Kerma for Some Br Compounds

2021 ◽  
Vol 2 (1) ◽  
pp. 024-029
Author(s):  
Tekerek Saniye ◽  
Küçükönder Adnan
Keyword(s):  
Electron Density ◽  
Attenuation Coefficient ◽  
Cross Section ◽  
Atomic Number ◽  
Gamma Ray ◽  
Effective Atomic Number ◽  
Mass Attenuation Coefficient ◽  
Transmission Method ◽  
Effective Electron ◽  
Mass Attenuation

The aim of this study is to calculate the experimental and theoretical the mass attenuation coefficient some Br compounds by using transmission method. Also using these values were determined the total electronic section, total atomic section, effective atomic number, effective electron density and Kerma. We performed the calculations of these values in attenuation by using direct excitation experimental geometry. The total attenuation cross sections of some halogene Br compounds were measured in a narrow beam good geometry using a high resolution Si(Li) detector in the energy with γ photons at 59.543 keV from Am-241 annular source. Theoretical mass attenuation coefficient values were computed from the XCOM data programme, based on mixture rule method. This study provide new insight into the literature since the values of effective atomic number, electron density and Kerma for some Br compounds have not been determined before. According to the results shown in mass attenuation coefficient, Zeff and Neff of Br compounds are closely associated with chemical structure. This research were undertaken to explore how Bromine compounds is gamma ray shielding material.

XUV Absorption Spectra of Carbon Ions

1988 ◽  
Vol 102 ◽  
pp. 71-73
Author(s):  
E. Jannitti ◽  
P. Nicolosi ◽  
G. Tondello
Keyword(s):  
Absorption Spectra ◽  
Cross Section ◽  
Theoretical Calculations ◽  
Photoionization Cross Section ◽  
Carbon Ions

AbstractThe photoabsorption spectra of the carbon ions have been obtained by using two laser-produced plasmas. The photoionization cross-section of the CV has been absolutely measured and the value at threshold, σ=(4.7±0.5) × 10−19cm2, as well as its behaviour at higher energies agrees quite well with the theoretical calculations.

Elastic Scattering in Electron Microscopy

1973 ◽  
Vol 31 ◽  
pp. 252-253
Author(s):  
J. Langmore ◽  
M. Isaacson ◽  
J. Wall ◽  
A. V. Crewe
Keyword(s):  
Electron Microscopy ◽  
Elastic Scattering ◽  
Cross Section ◽  
Quantum Noise ◽  
Dark Field ◽  
Elastic Cross Section ◽  
Biological Molecules ◽  
Dark Field Microscopy ◽  
Field Systems ◽  
Effects Of Radiation

High resolution dark field microscopy is becoming an important tool for the investigation of unstained and specifically stained biological molecules. Of primary consideration to the microscopist is the interpretation of image Intensities and the effects of radiation damage to the specimen. Ignoring inelastic scattering, the image intensity is directly related to the collected elastic scattering cross section, σɳ, which is the product of the total elastic cross section, σ and the eficiency of the microscope system at imaging these electrons, η. The number of potentially bond damaging events resulting from the beam exposure required to reduce the effect of quantum noise in the image to a given level is proportional to 1/η. We wish to compare η in three dark field systems.

A New Approach to the Demonstration of Oxidase-Localization Using Tannic Acid Or Catechin

1973 ◽  
Vol 31 ◽  
pp. 698-699
Author(s):  
V. Mizuhira ◽  
Y. Futaesaku
Keyword(s):  
Cross Section ◽  
Tannic Acid ◽  
Elastic Fiber ◽  
The Other ◽  
New Approach ◽  
Tissue Block ◽  
Active Reaction ◽  
The Cross

Previously we reported that tannic acid is a very effective fixative for proteins including polypeptides. Especially, in the cross section of microtubules, thirteen submits in A-tubule and eleven in B-tubule could be observed very clearly. An elastic fiber could be demonstrated very clearly, as an electron opaque, homogeneous fiber. However, tannic acid did not penetrate into the deep portion of the tissue-block. So we tried Catechin. This shows almost the same chemical natures as that of proteins, as tannic acid. Moreover, we thought that catechin should have two active-reaction sites, one is phenol,and the other is catechole. Catechole site should react with osmium, to make Os- black. Phenol-site should react with peroxidase existing perhydroxide.

Electron Irradiation Effects in Polyoxymethylene Crystals Grown Inside Trioxane Crystals

1971 ◽  
Vol 29 ◽  
pp. 78-79
Author(s):  
J. P. Colson ◽  
D. H. Reneker
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Detailed Examination ◽  
The Other ◽  
Electron Micrograph ◽  
Irradiation Effects ◽  
Threefold Axis ◽  
Typical Sample ◽  
Polymer Crystals ◽  
Chain Axis

Polyoxymethylene (POM) crystals grow inside trioxane crystals which have been irradiated and heated to a temperature slightly below their melting point. Figure 1 shows a low magnification electron micrograph of a group of such POM crystals. Detailed examination at higher magnification showed that three distinct types of POM crystals grew in a typical sample. The three types of POM crystals were distinguished by the direction that the polymer chain axis in each crystal made with respect to the threefold axis of the trioxane crystal. These polyoxymethylene crystals were described previously.At low magnifications the three types of polymer crystals appeared as slender rods. One type had a hexagonal cross section and the other two types had rectangular cross sections, that is, they were ribbonlike.

Freeze-Fracture Replication of Frozen Outer Segments of Rat Retinal Rods

1969 ◽  
Vol 27 ◽  
pp. 392-393
Author(s):  
Thomas S. Leeson ◽  
C. Roland Leeson
Keyword(s):  
Electron Microscopy ◽  
Cross Section ◽  
Outer Segment ◽  
Freeze Fracture ◽  
X Ray Diffraction ◽  
X Ray ◽  
Outer Segments ◽  
Retinal Rods ◽  
Temperature Electron ◽  
Freeze Etching

Numerous previous studies of outer segments of retinal receptors have demonstrated a complex internal structure of a series of transversely orientated membranous lamellae, discs, or saccules. In cones, these lamellae probably are invaginations of the covering plasma membrane. In rods, however, they appear to be isolated and separate discs although some authors report interconnections and some continuities with the surface near the base of the outer segment, i.e. toward the inner segment. In some species, variations have been reported, such as longitudinally orientated lamellae and lamellar whorls. In cross section, the discs or saccules show one or more incisures. The saccules probably contain photolabile pigment, with resulting potentials after dipole formation during bleaching of pigment. Continuity between the lamina of rod saccules and extracellular space may be necessary for the detection of dipoles, although such continuity usually is not found by electron microscopy. Particles on the membranes have been found by low angle X-ray diffraction, by low temperature electron microscopy and by freeze-etching techniques.

A quantitative approach to inner shell losses

1978 ◽  
Vol 36 (1) ◽  
pp. 526-527 ◽  
Author(s):  
R.D. Leapman ◽  
P. Rez ◽  
D.F. Mayers
Keyword(s):  
Energy Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Accurate Determination ◽  
Background Intensity ◽  
Core Excitation ◽  
Quantitative Basis ◽  
Cross Section Differential ◽  
Bound Electrons

Microanalysis by EELS has been developing rapidly and though the general form of the spectrum is now understood there is a need to put the technique on a more quantitative basis (1,2). Certain aspects important for microanalysis include: (i) accurate determination of the partial cross sections, σx(α,ΔE) for core excitation when scattering lies inside collection angle a and energy range ΔE above the edge, (ii) behavior of the background intensity due to excitation of less strongly bound electrons, necessary for extrapolation beneath the signal of interest, (iii) departures from the simple hydrogenic K-edge seen in L and M losses, effecting σx and complicating microanalysis. Such problems might be approached empirically but here we describe how computation can elucidate the spectrum shape.The inelastic cross section differential with respect to energy transfer E and momentum transfer q for electrons of energy E0 and velocity v can be written as

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