Photoproduction of Gravitational Radiation in Static Electromagnetic Fields. Radiative Corrections

1975 ◽  
Vol 53 (20) ◽  
pp. 2315-2320 ◽  
Author(s):  
G. Papini ◽  
S. -R. Valluri

The radiative corrections of second and third order for the process of photoproduction of gravitons in Coulomb and magnetic dipole fields have been calculated.All divergences have been removed either by charge renormalization or regularization. No approximations have been made in the calculation of the second order cross section. In the third order calculation only the extreme relativistic approximation is given. The forms of the effective Lagrangian, corresponding to the low energy approximations have been determined.

The expression for the cross-section obtained from the second Born approximation by including only terms to the third order in the interaction energy is employed to calculate cross-sections for the electron impact excitation of the 2 s level of atomic hydrogen, allow­ance being made for distortion and polarization due to the 1 s , 2 s and 2 p 0.± 1 intermediate states. These cross-sections are compared with the available experimental data.


2006 ◽  
Vol 19 (1) ◽  
pp. 133-141 ◽  
Author(s):  
Georgeta Budura ◽  
C. Botoca

Nonlinear adaptive filtering techniques are widely used for the nonlinearities identification in many applications. This paper proposes a new implementation of the third order RLS Volterra filter based on the decomposition of the input vector. Its performances are evaluated in a typical nonlinear system identification application. Different degrees of nonlinearity for the nonlinear system are considered. Comparations, based on the adaptive filter error, are made in all cases with a linear identifier. The experimental results show that the proposed nonlinear identifier has better performances than the linear one.


2001 ◽  
Vol 90 (2) ◽  
pp. 1064-1066 ◽  
Author(s):  
J. Olivares ◽  
J. Requejo-Isidro ◽  
R. del Coso ◽  
R. de Nalda ◽  
J. Solis ◽  
...  

1996 ◽  
Vol 74 (7-8) ◽  
pp. 554-558 ◽  
Author(s):  
Jack C. Straton ◽  
J. Wang ◽  
J. H. McGuire ◽  
L. Nagy

Techniques the authors developed to include correlation in the double-excitation of atoms are applied to a second two-electron process, excitation–ionization by proton versus antiproton impact. The second-order cross section, in the closure approximation and using pseudostates for the unbound electron, reproduces only a small percentage of the experimental factor of 2 difference for positively versus negatively charged projectiles. Inclusion of a portion of the third-order term yields a significant contribution near 0.5 MeV.


2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Cemil Tunç

This paper considers nonautonomous functional differential equations of the third order with multiple constant deviating arguments. Using the Lyapunov-Krasovskii functional approach, we find certain sufficient conditions for the solutions to be stable and bounded. We give an example to illustrate the theoretical analysis made in this work and to show the effectiveness of the method utilized here.


Author(s):  
Zhifeng Shao

A small electron probe has many applications in many fields and in the case of the STEM, the probe size essentially determines the ultimate resolution. However, there are many difficulties in obtaining a very small probe.Spherical aberration is one of them and all existing probe forming systems have non-zero spherical aberration. The ultimate probe radius is given byδ = 0.43Csl/4ƛ3/4where ƛ is the electron wave length and it is apparent that δ decreases only slowly with decreasing Cs. Scherzer pointed out that the third order aberration coefficient always has the same sign regardless of the field distribution, provided only that the fields have cylindrical symmetry, are independent of time and no space charge is present. To overcome this problem, he proposed a corrector consisting of octupoles and quadrupoles.


Author(s):  
Imre Pozsgai ◽  
Klara Erdöhalmi-Torok

The paintings by the great Hungarian master Mihaly Munkacsy (1844-1900) made in an 8-9 years period of his activity are deteriorating. The most conspicuous sign of the deterioration is an intensive darkening. We have made an attempt by electron beam microanalysis to clarify the causes of the darkening. The importance of a study like this is increased by the fact that a similar darkening can be observed on the paintings by Munkacsy’s contemporaries e.g Courbet and Makart. A thick brown mass the so called bitumen used by Munkacsy for grounding and also as a paint is believed by the art historians to cause the darkening.For this study, paint specimens were taken from the following paintings: “Studio”, “Farewell” and the “Portrait of the Master’s Wife”, all of them are the property of the Hungarian National Gallery. The paint samples were embedded in a polyester resin “Poly-Pol PS-230” and after grinding and polishing their cross section was used for x-ray mapping.


1973 ◽  
Vol 16 (2) ◽  
pp. 201-212 ◽  
Author(s):  
Elizabeth Carrow ◽  
Michael Mauldin

As a general index of language development, the recall of first through fourth order approximations to English was examined in four, five, six, and seven year olds and adults. Data suggested that recall improved with age, and increases in approximation to English were accompanied by increases in recall for six and seven year olds and adults. Recall improved for four and five year olds through the third order but declined at the fourth. The latter finding was attributed to deficits in semantic structures and memory processes in four and five year olds. The former finding was interpreted as an index of the development of general linguistic processes.


1971 ◽  
Vol 25 (02) ◽  
pp. 354-378 ◽  
Author(s):  
R Gottlob ◽  
L Stockinger ◽  
U Pötting ◽  
G Schattenmann

SummaryIn vitro whole blood clots of various ages, experimental thrombi produced in the jugular vein of rabbits and human thrombi from arteries and veins were examined in semi-thin sections and by means of electron microscopy.In all types of clots examined a typical course of retraction was found. Retraction starts with a dense excentrical focus which grows into a densification ring. After 24 hours the entire clot becomes almost homogeneously dense; later a secondary swelling sets in.Shortly after coagulation the erythrocytes on the rim of the clot are bi-concave discs. They then assume the shape of crenate spheres, turn into smooth spheres and finally become indented ghosts which have lost the largest part of their contents. In the inner zone, which makes up the bulk of the clot, we observed bi-concave discs prior to retraction. After retraction we see no crenations but irregularly shaped erythrocytes. Once the secondary swelling sets in, the cross-section becomes polygonal and later spherical. After extensive hemolysis we observe the “retiform thrombus” made up of ghosts.Experimental and clinical thrombi present the same morphology but are differentiated from in vitro clots by: earlier hemolysis, immigration of leukocytes, formation of a rim layer consisting of fibrin and thrombocytes, and the symptoms of organization. Such symptoms of organization which definitely will prevent lysis with streptokinase were found relatively late in experimental and clinical thrombi. Capillary buds and capillary loops were never found in clinical thrombi prior to the third month.The morphological findings agree with earlier physical and enzymatic investigations. The observation that phenomena of reorganization occur relatively late and frequently only in the rim areas of large thrombi explains why lytic therapy is possible in some of the chronic obliterations.


Sign in / Sign up

Export Citation Format

Share Document