scholarly journals Determination of the cross sections for the production of fragments from relativistic nucleus-nucleus interactions. I. Measurements

1990 ◽  
Vol 42 (6) ◽  
pp. 2508-2529 ◽  
Author(s):  
J. R. Cummings ◽  
W. R. Binns ◽  
T. L. Garrard ◽  
M. H. Israel ◽  
J. Klarmann ◽  
...  
Keyword(s):  
Cross Sections ◽  
Relativistic Nucleus ◽  
The Cross

scholarly journals Determination of the cross sections for the production of fragments from relativistic nucleus-nucleus interactions. II. Parametric fits

1990 ◽  
Vol 42 (6) ◽  
pp. 2530-2545 ◽  
Author(s):  
J. R. Cummings ◽  
W. R. Binns ◽  
T. L. Garrard ◽  
M. H. Israel ◽  
J. Klarmann ◽  
...  
Keyword(s):  
Cross Sections ◽  
Relativistic Nucleus ◽  
The Cross

The determination of the cross sections for the reactions 27 Al( n , α ) and 56 Fe( n , p ) for 14 MeV neutrons by an absolute method

1966 ◽  
Vol 292 (1429) ◽  
pp. 180-192 ◽  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Standard Error ◽  
Particle Method ◽  
Systematic Errors ◽  
Aluminium Foil ◽  
The Mean ◽  
The Cross ◽  
Experimental Values

Measurements of the cross sections for the reactions 27 Al( n , α ) 24 Na and 56 Fe( n, p ) 56 Mn for neutrons of energy 13.5 ± 0.1 MeV have been made by a radioactivation method. The neutron flux was determined by a variant of the 'associated particle’ method, in which the α -particles produced concurrently with the neutrons from the D + T reaction were estimated in terms of the volume of helium which accumulated when they were brought to rest in an aluminium foil. Cross section values obtained at 13.5 MeV were: for 27 Al( n , α ): 118.1 ± 6.0 mb : for 56 Fe( n, p ): 106.7 ± 4.7 mb. The errors quoted include both the standard error on the mean of the experimental values and an estimate of possible residual systematic errors. The excitation functions for both reactions in the energy region 13.5 to 14.8 MeV have also been investigated, in order to provide secondary cross section values over this range of energies. At 14.8 MeV the values found were: 27 Al( n , α )103.6 ± 5.5 mb; 56 Fe( n, p )96.7 ± 4.5 mb.

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.

The determination of cross sections for quenching of resonance radiation of metal atoms III. Results for thallium

1968 ◽  
Vol 303 (1475) ◽  
pp. 467-475 ◽  
Keyword(s):  
Carbon Dioxide ◽  
Cross Section ◽  
Cross Sections ◽  
Rate Constants ◽  
Resonance Radiation ◽  
Metal Atoms ◽  
The Cross

The intensity of fluorescence of thallium has been measured in hydrogen-oxygen flames diluted with each of the gases, argon, helium, nitrogen and carbon dioxide and the measurements used to obtain the following values for the quenching cross section (Å 2 ) for the 7 s 2 S ½ state of thallium σ 2 H 2 = 0.03, σ 2 O 2 = 13.2 ± 1.5, σ 2 N 2 = 6.4 ± 0.2, σ 2 H 2 O = 1.75 ± 0.2, σ 2 CO = 13.6 ± 0.8, σ 2 CO 2 = 32.5 ± 1.5, σ 2 Ar ≤ 0.1, σ 2 He ≤ 0.12. These values for the cross sections have been used to re-calculate the rate constants of the reactions, Tl + H + X → H X + Tl*, where X = H, OH, Cl or Br, from the data obtained by Phillips & Sugden (1961). The re-calculated values are lower than the original ones by a factor of 2.2.

scholarly journals Design and Diagnostics of High-Precision Accelerator Neutrino Beams

2021 ◽  
Vol 11 (4) ◽  
pp. 1644
Author(s):  
Nikolaos Charitonidis ◽  
Andrea Longhin ◽  
Michelangelo Pari ◽  
Elisabetta Giulia Parozzi ◽  
Francesco Terranova
Keyword(s):  
Ab Initio ◽  
Neutrino Oscillation ◽  
High Precision ◽  
Cross Sections ◽  
Neutrino Energy ◽  
Event Reconstruction ◽  
Cent Level ◽  
The Cross

Neutrino oscillation physics has entered a new precision era, which poses major challenges to the level of control and diagnostics of the neutrino beams. In this paper, we review the design of high-precision beams, their current limitations, and the latest techniques envisaged to overcome such limits. We put emphasis on “monitored neutrino beams” and advanced diagnostics to determine the flux and flavor of the neutrinos produced at the source at the per-cent level. We also discuss ab-initio measurements of the neutrino energy–i.e., measurements performed without relying on the event reconstruction at the ν detector–to remove any flux induced bias in the determination of the cross sections.

Absolute determination of the cross sections of ozone in the wavelength region 339-355 nm at temperatures 220-293 K

1989 ◽  
Vol 94 (D6) ◽  
pp. 8485-8490 ◽  
Author(s):  
Marco Cacciani ◽  
Alcide di Sarra ◽  
Giorgio Fiocco ◽  
Antonella Amoruso
Keyword(s):  
Cross Sections ◽  
Wavelength Region ◽  
Absolute Determination ◽  
The Cross

Decomposition-Based Assembly Synthesis of Space Frame Structures Using Joint Library

2004 ◽  
Author(s):  
Naesung Lyu ◽  
Kazuhiro Saitou
Keyword(s):  
Finite Element ◽  
Cross Sections ◽  
Structural Characteristics ◽  
Finite Element Analyses ◽  
Space Frame ◽  
Multi Objective Genetic Algorithm ◽  
Joint Location ◽  
The Cross

This paper presents a method for identifying the optimal designs of components and joints in the space frame body structures of passenger vehicles considering structural characteristics, manufacturability and assembleability. Dissimilar to our previous work based on graph decomposition, the problem is posed as a simultaneous determination of the locations and types of joints in a structure and the cross sections of the joined structural frames, selected from a predefined joint library. The joint library is a set of joint designs containing the geometry of the feasible joints at each potential joint location and the cross sections of the joined frames, associated with their structural characteristics as equivalent torsional springs obtained from the finite element analyses of the detailed joint geometry. Structural characteristics of the entire structure are evaluated by finite element analyses of a beam-spring model constructed from the selected joints and joined frames. Manufacturability and assembleability are evaluated as the manufacturing and assembly costs estimated from the geometry of the components and joints, respectively. The optimization problem is solved by a multi-objective genetic algorithm using a direct crossover. A case study on an aluminum space frame (ASF) of a middle size passenger vehicle is discussed.

The determination of cross sections for the quenching of resonance radiation of metal atoms I. Experimental method and results for sodium

1966 ◽  
Vol 293 (1435) ◽  
pp. 493-511 ◽  
Keyword(s):  
Experimental Method ◽  
Cross Sections ◽  
Resonance Radiation ◽  
Line Broadening ◽  
Compound Formation ◽  
Metal Atoms ◽  
Sodium Atoms ◽  
The Cross ◽  
Oxygen Flame

A method of determining the cross sections for the quenching of excited metal atoms by molecules and atoms which may be present in flames is described. The method has been applied to the quenching of sodium atoms in the 3 p 2 P state and the following results (in Å 2 ) for the square of the distance between the centres of colliding species, σ 2 , obtained: σ 2 H 2 = 2.87 ± 0.1; σ 2 N 2 = 6.95 ± 0.15; σ 2 CO = 11.9 ± 0.4; σ 2 CO 2 = 17.0 ± 0.4; σ 2 H 2 O = 0.5 ± 0.3; σ 2 O 2 = 12.3 ± 0.5; σ 2 Ar < 0.1; σ 2 He < 0.1. These cross sections have been measured at temperatures in the range 1400°K to about 1800°K and found to be independent of the temperature. The values for the cross sections are derived from measurements of the fluorescence of sodium in hydrogen-oxygen flame diluted with various other gases. This method is believed to be free of uncertainties due to self-absorption, compound formation, line broadening effects and uncertain velocity distributions. Where values for cross sections have been obtained by other workers they are compared with these results and possible reasons for the discrepancies are discussed.

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