Experimental results on the cross section for π− πo → π− ωo

1963 ◽  
Vol 5 (3) ◽  
pp. 209-211 ◽  
Author(s):  
L. Bondàr ◽  
E. Keppel ◽  
G. Kraus ◽  
W.P. Dodd ◽  
B. Tallini ◽  
...  
1968 ◽  
Vol 46 (10) ◽  
pp. S377-S380 ◽  
Author(s):  
A. A. Petrukhin ◽  
V. V. Shestakov

The cross section for the muon bremsstrahlung process is calculated as a function of the nuclear form factor in the Born approximation following the Bethe and Heitler theory. The influence of the nuclear form factor is greater than that taken by Christy and Kusaka. The simple analytical expression for the effect of the screening of the atomic electrons is found. The influence of a decrease in the cross section upon the interpretation of some experimental results is estimated.


2019 ◽  
Vol 116 (6) ◽  
pp. 607 ◽  
Author(s):  
Rong Cheng ◽  
Jiongming Zhang ◽  
Liangjin Zhang ◽  
Haitao Ma

Unlike traditional rolling processes, reduction of rolling process of rail is along two vertical directions and the broadening of rolled piece is controlled. In this study, industrial experiments and a simulation model of the rolling process of rail were conducted to investigate the behaviors of porosities in billet during the rolling process of rail. The experimental and simulated results revealed that porosities moved toward the center on the cross section of the rolled piece and the porosities region reduced from a rectangle with the size (76.7 × 93.3 mm) to an isosceles trapezoid with the size {(12.8 + 18.5 mm) × 47.2 mm} during the rolling process of rail. The shapes of the porosities changed from circles with the diameters smaller than 6 mm to short cracks with the lengths shorter than 10 mm on the cross section. The two vertical reduction directions and the controlled broadening of rolled piece both counted against the closure of porosity. The simulated results were mostly in agreement with the experimental results.


1986 ◽  
Vol 1 (20) ◽  
pp. 155
Author(s):  
Hitoshi Murakami ◽  
Yoshihiko Hosoi ◽  
Yoshitaka Goda

This paper discusses the characteristics of hydraulic and water exchange due to the wave action against vertical slit-type breakwaters. The theoretical solution of the reflection and the transmission coefficients for the breakwater models is compared with the experimental results. Furthermore, the water exchange discharge and the water concentration change through the gap of the permeable breakwater are examined experimentally. Finally the most effective geometry of the cross section is suggested for the breakwaters used here.


2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Manahel Sh. Khalaf ◽  
Amer M. Ibrahim

This paper investigates the ovalisation behavior of the Steel Circular Hollow Sections (CHSs) when subjected to bending moment. The experimental program included testing of ten specimens in four groups in order to examine the influence of changing the diameter, thickness, length and the presence of openings on the ovalisation phenomenon of these specimens.The experimental results showed that the ovalisation of the specimen cross-section appears clearly when the diameter to thickness ratio (D/t) is ranging from 17 to 50, while the ovalisation of the specimens that have D/t ratio greater than 50 is very little or unclear because the instability of these specimens are controlled by the local buckling. In addition, the change of the specimen length and the presence of openings didn’t cause the cross-section ovalisation


1964 ◽  
Vol 6 (3) ◽  
pp. 211-218 ◽  
Author(s):  
A. D. S. Barr ◽  
T. Duthie

Approximate differential equations describing the bending vibration of beams of thin-walled H section, in which the distortion of the cross-section in its own plane is taken into account, are derived from Hamilton's principle using an assumed form for the cross-section deformation. Only the simplest of the cross-sectional deformation configurations which will couple with ordinary bending is considered. The variation with wavelength of the two spectra of frequencies which result from this coupling of the bending and cross-sectional motions is shown for several section geometries. Theoretical curves show reasonable agreement with experimental results from free beams.


The cross-sections have been measured for reactions produced by deuterons in platinum, gold, mercury, thallium, lead, bismuth, thorium and uranium, using deuterons of 9 MeV energy from the Cavendish cyclotron. The observed values of σ for the ( d, p ) reaction vary from 30 x 10 -27 cm. 2 for platinum to 5 x 10 -27 cm. 2 for uranium. The values for the ( d, n ) reaction are about one-fifth of those for the ( d, p ) reaction. Calculations of the cross-sections to be expected on theoretical grounds, have been made for two different values of the standard nuclear radius R 0 , namely, 2.0 x 10 -13 and 1.47 x 10 -13 cm. The experimental results are shown to favour the lower of these values.


1979 ◽  
Vol 91 (3) ◽  
pp. 401-414 ◽  
Author(s):  
E. J. Hinch ◽  
A. Acrivos

The recent analysis by Acrivos & Lo (1978) concerning the breakup of a long slender droplet in an axisymmetric straining motion is extended to the case of a two-dimensional hyperbolic flow. It is found that, although the cross-section of the droplet becomes significantly non-circular, the theoretical criterion for breakup is effectively the same as in the axisymmetric case. The theoretical predictions are in good agreement with the available experimental results.


1989 ◽  
Vol 04 (09) ◽  
pp. 2273-2281
Author(s):  
MARTIN ZERNER

We study the lattice approximation to Reggeon Field Theory. An approximate computation of the renormalized Pomeron intercept is proposed and shows that it is equal to one as required for the theory to be consistent with experimental results and with Froissart’s bound. A stricter derivation of this requirement is also given. At fixed impact parameter the cross section seems to be asymptotically bounded.


2018 ◽  
Vol 5 (4) ◽  
pp. 382-390 ◽  
Author(s):  
S.H. Lee ◽  
E.S. Kim ◽  
J.Y. Park ◽  
J. Choi

Abstract In the automotive industry, metal inert gas (MIG) of welding technology is widely used for automotive muffler fabrication. However, the muffler is distorted by thermal deformation during the welding process. In this paper, the prediction of MIG welding-induced deformation and residual stress are simulated by SYSWELD software. The cross-section shapes of the molten pool predicted by the numerical analysis are compared to the experimental results. In the results of the stress, while compressive stresses are produced in regions away from the weld, high tensile stresses are produced in regions near the weld. Deformation values are calculated as 2.5 mm. The location of the actual welding deformation was similar to the experimental results. Based on the results, the methods to optimize the welding procedure will be provided by SYSWELD to improve muffler productivity. Highlights The prediction of MIG welding-induced deformation and residual stress are simulated by SYSWELD software. The cross-section shapes of the molten pool predicted by the numerical analysis are compared to the experimental results. The location of the actual welding deformation are similar to the experimental results. Based on the results, the methods will be provided by SYSWELD to improve muffler productivity.


Atoms ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 5
Author(s):  
Raúl O. Barrachina ◽  
Francisco Navarrete ◽  
Marcelo F. Ciappina

In the study of collision processes, a series of conditions is usually assumed. One of them is that the beam of projectiles is coherent in lengths greater than those of the targets against which it strikes. However, recent experimental results and theoretical analyzes have shown that this assumption can not only fail, but that it is possible to manipulate the coherence length experimentally to go from a coherent situation to an incoherent one. The most conspicuous and studied manifestation of such loss of coherence is the disappearance of interference effects. However, in the present work we show that a strong decrease can also occur in the magnitude of the cross section, not only differential but also total, due to an atomic concealment effect.


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