scholarly journals Radiative Correction to e+e-->e+e- in the Electroweak Theory. II: Corrected Elastic Cross Section and Positron Energy Spectrum

1986 ◽  
Vol 75 (4) ◽  
pp. 905-913 ◽  
Author(s):  
K. Tobimatsu ◽  
Y. Shimizu
Author(s):  
J. Langmore ◽  
M. Isaacson ◽  
J. Wall ◽  
A. V. Crewe

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.


1987 ◽  
Vol 77 (1) ◽  
pp. 118-131 ◽  
Author(s):  
J. Fujimoto ◽  
M. Igarashi ◽  
Y. Shimizu

2021 ◽  
Author(s):  
Sviatoslav Iuras ◽  
Samira Ahmad ◽  
Chiara Cavalleri ◽  
Yernur Akashev

Abstract Ukraine ranks the third largest gas reserves in Europe. Gas production is carried out mainly from the Dnieper-Donets Basin (DDB). A gradual decline in reserves is forcing Ukraine to actively search for possible sources to increase reserves by finding bypassed gas intervals in existing wells or exploration of new prospects. This paper describes 3 case studies, where advanced pulsed neutron logging technology has shown exceptional value in gas-bearing layer identification in different scenarios. The logging technology was applied for formation evaluation. The technology is based on the neutron interaction with the minerals and the fluids contained in the pore space. The logging tool combines measurements from multiple detectors and spacing for self-compensated neutron cross-capture section (sigma) and hydrogen index (HI), and the Fast Neutron Cross Section (FNXS) high-energy neutron elastic cross section rock property. Comprehensive capture and inelastic elemental spectroscopy are simultaneously recorded and processed to describe the elemental composition and the matrix properties, reducing the uncertainties related to drilling cuttings analysis, and overall, the petrophysical evaluation combined with other log outputs. The proposed methodology was tested in several wells, both in open hole and behind casing. In the study we present its application in three wells from different fields of the DDB. The log data acquisition and analysis were performed across several sandstone beds and carbonates formation with low porosities (<10%), in various combinations of casing and holes sizes. The results showed the robustness and effectiveness of using the advanced pulsed neutron logging (PNL) technologies in multiple cases: Case Study A: Enabling a standalone cased hole evaluation and highlighting new potential reservoir zones otherwise overlooked due to absence of open hole logs. Case Study B: Finding by-passed hydrocarbon intervals that were missed from log analysis based on conventional open hole logs for current field operator. Case Study C: Identifying gas saturated reservoirs and providing solid lithology identification that previously was questioned from drilling cuttings in an unconventional reservoir.


2018 ◽  
Vol 172 ◽  
pp. 06005
Author(s):  
Jan Kašpar

This contribution reviews and compares various LHC results on soft diffraction, in particular elastic scattering, total, inelastic and elastic cross-section, single and double diffraction.


2020 ◽  
pp. 39-46
Author(s):  
О. Kukhotska ◽  
I. Ovdiienko ◽  
M. Ieremenko

The paper presents the results of uncertainty analysis of WWER‑1000 core macroscopic cross sections due to spectral effects during WWER‑1000 fuel burnup and the analysis of cross section sensitivity from thermophysical parameters of the calculated cell, which affect energy spectrum of neutron flux density. The calculation of changes in the isotopic composition during burnup and the preparation of macroscopic cross sections used the developed HELIOS computer model [1] for TVSA, which is currently operated at most Ukrainian WWER‑1000 units. The GRS approach applying Software for Uncertainty and Sensitivity Analyses (SUSA) [2] was chosen to assess the uncertainty of the macroscopic cross sections due to spectral effects and analysis of cross section sensitivity from thermophysical parameters. The spectral effect on macroscopic cross sections was taken into account by calculating the fuel burnup for variational sets of thermophysical parameters (fuel temperature, coolant temperature and density, boric acid concentration) prepared in advance by the SUSA program, as a result of which fuel isotopic composition vectors were obtained. After that, neutronic constants for the reference state were developed for each of the sets of isotopic composition, which corresponded to a certain set of thermophysical parameters. At the next stage, the uncertainty of macroscopic cross sections of the interaction due to the spectral effects on the isotopic composition of the fuel was analyzed using SUSA 4, followed by the analysis of cross section sensitivity from thermophysical parameters of the calculated cell affecting energy spectrum of neutron flux density. In the future, the uncertainty of two-group macroscopic diffusion constants can be used to estimate the overall uncertainty of neutronic characteristics in large-grid core calculations, in particular, in the safety analysis.


Sign in / Sign up

Export Citation Format

Share Document