Atomic Disintegration Research Articles

Holonomies for foliations with extreme disintegration behavior

Given a foliation, we say that it displays “extreme disintegration behavior” if either it has atomic disintegration or if it is leafwise absolutely continuous and its conditional measures are uniformly equivalent to the leaf volume, which we call UDB property. Both concepts are related to the decomposition of volume with respect to the foliation. We relate these behaviors to the measure-theoretical regularity of the holonomies, by proving that a foliation with atomic disintegration has holonomies taking full volume sets to zero volume sets, and we characterize the UBD property with the holonomies having uniformly bounded Jacobians. Both extreme phenomena appear in invariant foliations for dynamical systems.

The molecular dynamics simulation of coronavirus- based compound (6OHW structure) interaction with interferon beta-1a protein at different temperatures and pressures: Virus destruction process

The Interferon beta-1a protein is a cytokine in the Interferon family that is used to treat a variety of ailments. Molecular Dynamics simulation was used to characterize the atomic disintegration of 6OHW structure of a corona virus-based compound with Interferon beta-1a protein in this computational study. Molecular Dynamics simulation results on the atomic evolution of the 6OHW structure were presented with estimating physical variables. Physically, our simulations showed the attraction forces between the virus and the atomic protein in the presence of H2O molecules, resulting in viral annihilation after t = 10 ns. The molecular dynamics package's initial pressure and temperature (Temp) changes were important for virus-protein system evolution. Numerically, increasing primary T and P from 300 K and 1 bar to 350 K and 5 bar reduced the atomic distance between virus and protein structures from 10 Å to 2.71 Å and 2.45 Å. Bonding energy was another reported physical quantity in our Molecular Dynamics simulation work. The atomic parameter ranged from 152.57 kcal/mol to 148.54 kcal/mol due to changes in initial Temp and pressure. Ultimately, the diffusion coefficient of protein being simulated inside the atomic virus changed from 0.48 μm2/s to 0.59 μm2/s. This calculation demonstrated the suitable conduct of simulated protein throughout virus destruction process.

Conditions for Atomic Disintegration to be Monoatomic

Conditions for Atomic Disintegration to be Monoatomic

Possible relationship of meteor disintegration in the mesosphere and enhancement of sodium atoms: A case study on july 05, 2013

• Possible relationship of meteor disintegration and enhancement of sodium atoms. • The sodium cloud was carried away by the horizontal wind and suggest that the increase in sodium density at São José dos Campos is a dynamical process. • The all-sky images show that the sodium cloud around 90 km was formed along the bright part of the fireball. Our observations show that on some occasions an influx of meteor ablation possibly contributes to appearance of a sudden enhancement in mesospheric sodium density. On July 05, 2013, all-sky images with a narrow sodium filter in the 589 nm emission, operating at Cachoeira Paulista (22.7° S, 45° W) and lidar observations of the mesospheric sodium layer, operating at São José dos Campos (23.1° S, 45.9° W), both observatories in Brazil, show a possible relationship of meteor disintegration and appearance of sodium enhancements on the background layer. After the meteor impact, the all-sky images showed a sodium cloud that was seen for about 10 min through the images in the NaD 589 nm emission, with initial dimensions of approximately 36 km × 9 km and initial speed of about 90 m/s southward. In addition, our observations show that the movement of sodium cloud in the horizontal plane around 90 km is relatively anisotropic and change the dimensions with time.

Response of free-standing graphene monolayer exposed to ultrashort intense XUV pulse from free-electron laser.

The response of a free-standing graphene monolayer exposed to a few tens of femtoseconds long extreme ultraviolet (XUV) pulse was studied theoretically in order to analyze and compare contributions of various mechanisms to the graphene damage, understood here as a global atomic disintegration. Our simulation results indicate that nonthermal disintegration of the atomic structure is the predominant damage mechanism for a free-standing graphene layer. Only at high absorbed doses, charge-induced disintegration of the graphene structure prevails. We also demonstrate that the progressing damage can be probed by femtosecond optical pulses in the soft UV regime (4eV photon energy). The achieved quantitative understanding of the damage mechanisms may enable a better control of graphene-based devices when they are exposed to x-ray radiation, as well as an efficient processing of graphene layers with ultrashort intense XUV pulses.

Ernest Rutherford’s ambitions

One of the pioneers of radioactivity research, Rutherford feared his work would be overlooked—and changed his publishing strategies to make sure it wasn’t.

Effect of ionizing radiation towards human health: A review

This paper reviews the properties, process and effect of ionizing radiation towards human health. The fetus and human embryo are much sensitive to ionizing radiation. The health consequences of exposure can be vary even at low radiation and as a result it will affect the mother. Such consequences can include cancer, malformations, growth retardation and impaired brain function. There are two types of biological effects which is deterministic and stochastic effect. Biological effect of radiation results from both direct and indirect action of radiation. Radiation exposure may be external or internal and can be acquired through various exposure pathways. Different organs have different sensitivity to ionizing radiation. Ionizing radiation is a radiation that carries enough energy to liberate electrons from atoms or molecules, thereby ionizing them. Ionizing radiation is made up of energetic subatomic particles, ions or atoms moving at high speeds such as alpha, beta, gamma, neutron particles and X-rays. The spontaneous disintegration of atoms is known as radioactivity and the excess energy emitted is a form of ionizing radiation. As the use of ionizing radiation increases, so does the potential for health hazards.

Atomic disintegrations for partially hyperbolic diffeomorphisms

Shub and Wilkinson and Ruelle and Wilkinson studied a class of volume preserving diffeomorphisms on the three dimensional torus that are stably ergodic. The diffeomorphisms are partially hyperbolic and admit an invariant central foliation of circles. The foliation is not absolutely continuous; in fact, Ruelle and Wilkinson established that the disintegration of volume along central leaves is atomic. We show that in such a class of volume preserving diffeomorphisms the disintegration of volume along central leaves is a single delta measure. We also formulate a general result for conservative three dimensional skew product like diffeomorphisms on circle bundles, providing conditions for delta measures as disintegrations of the smooth invariant measure.

Center foliation: absolute continuity, disintegration and rigidity

In this paper we address the issues of absolute continuity for the center foliation, as well as the disintegration on the non-absolute continuous case and rigidity of volume-preserving partially hyperbolic diffeomorphisms isotopic to a linear Anosov automorphism on $\mathbb{T}^{3}$. It is shown that the disintegration of volume on center leaves for these diffeomorphisms may be neither atomic nor Lebesgue, in contrast to the dichotomy (Lebesgue or atomic) obtained by Avila, Viana and Wilkinson [Absolute continuity, Lyapunov exponents and rigidity I: Geodesic flows. Preprint, 2012, arXiv:1110.2365v2] for perturbations of time-one of geodesic flow. In the case of atomic disintegration of volume on the center leaves of an Anosov diffeomorphism on $\mathbb{T}^{3}$, we show that it has to be one atom per leaf. Moreover, we show that not even a $C^{1}$ center foliation implies a rigidity result. However, for a volume-preserving partially hyperbolic diffeomorphism isotopic to a linear Anosov automorphism, assuming the center foliation is $C^{1}$ and transversely absolutely continuous with bounded Jacobians, we obtain smooth conjugacy to its linearization.

Minimal yet measurable foliations

In this paper we mainly address the problem of disintegration of Lebesgue measure along the central foliation of volume-preserving diffeomorphisms isotopic to hyperbolic automorphisms of 3-torus. We prove that atomic disintegration of the Lebesgue measure (ergodic case) along the central foliation has the peculiarity of being mono-atomic (one atom per leaf). This implies the measurability of the central foliation. As a corollary we provide open and nonempty subset of partially hyperbolic diffeomorphisms with minimal yet measurable central foliation.

Compton upconversion of twisted photons: backscattering of particles with non-planar wave functions

Twisted photons are not plane waves, but superpositions of plane waves with a defined projection hbar m of the orbital angular momentum onto the propagation axis (m is integer and may attain values m >> 1). Here, we describe in detail the possibility to produce high-energy twisted photons by backward Compton scattering of twisted laser photons on ultra-relativistic electrons with a Lorentz-factor gamma=E/(m_e c^2) >> 1. When a twisted laser photon with the energy hbar omega ~ 1 eV performs a collision with an electron and scatters backward, the final twisted photon conserves the angular momentum m, but its energy hbar omega' is increased considerably: omega'/omega=4 gamma^2/(1+x), where x=4E hbar omega/(m_e c^2)^2. The S matrix formalism for the description of scattering processes is particularly simple for plane waves with definite 4-momenta. However, in the considered case, this formalism must be enhanced because the quantum state of twisted particles cannot be reduced to plane waves. This implies that the usual notion of a cross section is inapplicable, and we introduce and calculate an averaged cross section for a quantitative description of the process. The energetic upconversion of twisted photons may be of interest for experiments with the excitation and disintegration of atoms and nuclei, and for studying the photo-effect and pair production off nuclei in previously unexplored regimes.

Generation of High-Energy Photons with Large Orbital Angular Momentum by Compton Backscattering

Usually, photons are described by plane waves with a definite 4-momentum. In addition to plane-wave photons, "twisted photons" have recently entered the field of modern laser optics; these are coherent superpositions of plane waves with a defined projection hm of the orbital angular momentum onto the propagation axis, where m is an integer. In this Letter, we show that it is possible to produce high-energy twisted photons by Compton backscattering of twisted laser photons off ultrarelativistic electrons. Such photons may be of interest for experiments related to the excitation and disintegration of atoms and nuclei, and for studying the photoeffect and pair production off nuclei in previously unexplored experimental regimes.

STILL BLAZING TRAILS AT 75

IT MIGHT BE THE TEST OF A TRUE scientist: Is your idea of the perfect summer trip a week relaxing on a sun-kissed beach or a week holed up in an otherwise deserted prep school campus in New England, debatingyour latest results with 100 of your colleagues and competitors? Despite their reputation for cafeteria food and dorm-style accommodations, the Gordon Research Conferences (GRC) remain the highlight of many a scientist's summer. Now in their 75th year, these much-loved conferences continue to shape both the lives of scientists and the frontiers of scientific research. The conferences have a long and storied history at the leading edge of science. Enrico Fermi described the slow-neutron process of atomic disintegration to a Gordon conference audience in 1936, a decade before the atomic bomb was unleashed on the world. The implications of recombinant DNA technology first came to the fore at the 1973 Gordon conference on nucleic acids. More recently, ...

EUCLIDEAN RESONANCE: APPLICATION TO PHYSICAL AND CHEMICAL EXPERIMENTS

The phenomenon of Euclidean resonance (a strong enhancement of quantum tunneling through a nonstationary potential barrier) is applied to disintegration of atoms and molecules through tunnel barriers formed by applied constant and time-dependent electric fields. There are two different channels for such disintegration, electronic and ionic. The electronic mechanism is associated with the ionization of a molecule into an electron and a positive ion. The required frequencies are in a wide range between 100 MHZ and infrared. This mechanism may constitute a method of selective destruction of chemical bonds. The ionic mechanism consists of dissociation of a molecule into two ions. Since an ion is more massive than an electron, the necessary frequency is about 1 MHZ. This provides a theoretical possibility of a different method of isotope separation by radio frequency waves. The small sub-barrier tunneling probability of nuclear processes can be dramatically enhanced by collision with incident charged particles. Semiclassical methods of theory of complex trajectories have been applied to nuclear tunneling, and conditions for the effect have been obtained. The enhancement of α particle decay by incident proton with energy of about 0.25 MeV has been demonstrated. The general features of this process are common for other sub-barrier nuclear processes and can be applied to nuclear fission.

Positronium Atom in Solids -Peculiarities of Formation and Interconnection with Free Volume Nanostructure-

l. Introduction to new atoms One feature of the vehement growth of physics in the 20th century is, undoubtedly, the correlation of this science with other fields of human endeavor, their mutual enrichment. The recent several decades have seen the spectacular advances, for example, in a new area at the junction of elementary-particle physics and chemistry, the so-called chemistry of new atoms, in which either an electron is replaced by another negative particle or a proton by another positive particle. This area of research does not confine itself to chemical studies alone. External influences on the properties of new atoms, and also those of mesons and positrons, provide useful, sometimes unique, information about the structure of solids. Therefore, unlike other reviews on positron annihilation, this paper includes a special part, describing intrinsic properties of positronium in comparison with properties and composition of other new atoms, so that this part can be considered as a general introduction into the field of new atoms. On example of positronium, the main part of this paper demonstrates external influences of the surrounding matter on properties and characteristics of one of the new atoms and the use of this effect for structural studies in solids. Correspondingly, a newcomer will find in this paper a little more than one of the special applications of the positron annihilation method. Atoms with an electron replaced by a negative meson are called mesoatoms. When chemically bound to conventional molecules and radicals they form mesomolecules. Typical examples are µ- and π-mesoatoms. Also possible in principle are E-mesoatoms, in which an electron is replaced by a negative hyperon, antiproton, or antihyperon. Atoms with a proton replaced by a positive particle are called by the name of that particle with an ending ‘ium’. Since a penetration of any positive particle into a nucleus is hindered by Coulomb repulsion (which can be compensated for by the nuclear forces alone), for light positive particles not involved in nuclear interactions, such as positrons e + and µ + -mesons, the atoms of this type cannot have nuclei consisting of many nucleons. These atoms only form when a positive lepton replaces a single nucleon, namely, a proton. In that case, an atom of a positron and an electron is called positronium (Ps). A bound system of µ + -meson (positive muon) and an electron is known as muonium (Mu). Both atoms can be treated as light isotopes of hydrogen. What is more, positronium is the lightest of all known new atoms, the only atom without a nucleus. In fact, since both constituent particles have the same mass, the centre of mass does not coincide with any of them (otherwise such a particle could be regarded as a nucleus), but lies strictly in between them. A nuclear proton can also be replaced by a positively charged hyperon in much the same way as a neutron by a neutral hyperon. The result is the so-called hypernuclei, and the corresponding atoms are referred to as hyperatoms. The structure of their electron shells and their chemical properties are, however, essentially the same as in conventional atoms with the same nuclear charge. Therefore, hyperatoms are generally not included into the list of new atoms. Interest in new atoms chiefly comes from the fact that their characteristics are appreciably influenced by the chemical properties and the structure of their environment. We will be looking at them in more detail in the next section. Examination of the characteristics of new atoms can supply unique evidence concerning the properties of the environment. One important characteristic of new atoms is their lifetime (all of them unstable). The decay characteristics of new atoms are studied using the apparatus of nuclear physics. The first stage of new atom research is the study of the laws by which the environment affects the characteristics and fate of new atoms. The second stage, more important for other research fields, consists in obtaining more complete and new structural and chemical data or data on the kinetics of certain processes based on observations of characteristics of formation, transformation, and disintegration of various new atoms. At the present time both the investigations into annihilation (death) of positrons and positronium and the mesochemical studies of µ- and π-mesoatoms and muonium have attained the second stage and started to yield information of general chemical significance. The field is very extensively promising. The aim of this review is not to embrace the whole problem of “new atoms” or the most of directions of positron annihilation studies. Instead, after general introduction into physics and methodology, detailed discussion is given of so called positronium pick-off annihilation and application of this effect for the studies of the free volume nanostructure in solids, in polymers particularly.

A history of nuclear transmutations by natural alpha particles

A systematic account of the use of alpha particles up to the 1930s for promoting the disintegration of atoms is here provided. As will be shown, a number of different radium family alpha sources were used in the experiments that led to the discoveries of the proton (Rutherford E 1919 Phil. Mag. 37 581–7) and neutron (Chadwick J 1932 Nature 129 312). The reasons leading to the employment of a particular alpha particle source, as well as the relationship between these sources and the available methods of recording, will be closely addressed.

Optimal Parameter Determination for Tritiated Water Storage in Polyacrylic Networks

Due to the remarkable capacity of water retaining, croslinked polyacrylic acids (PAA) represent an interesting alternative for tritiated water trapping. The study was developed on radiolytical processes in PAA:HTO systems derivated from irradiation of polymeric network by disintegration of tritium atoms from HTO. The aim of these studies is the identification of polymeric structures and optimal storage conditions.Sol and gel fractions were determinated by radiometrical methods using PAA labeled with 14-C at carboxylic groups and T at main chains of the polymer. Simulation of radiolytical processes was realized using γ radiation field emitted by a irradiation source of 60-Co which ensures a maximum of absorbed dose rate of 3 kGy/h. Self-radiolytical effects were investigated using labeled PAA in HTO with great radioactive concentration (37-185 GBq/mL). The experiment suggests as optimum for HTO storage as tritium liquid wastes a 1:30 PAA:HTO swelling degree at 18.5-37 MBqL. HTO radioactive concentration.RES studies of radiolytical processes were also realized on dry polyacrylic acid (PAA) and polyacrylic based hydrogels irradiated and determined at 77 K. In the study we observed the effect of swelling capacity of hydrogel o the formation of free radicals.

Explosive Propositions: Artists React to the Atomic Age

Argument“How should a modern artist react to the atomic age?” Time magazine posed this question in 1952 to open a review of an exhibition of paintings inspired by the “explosion of the atomic bomb” and by the “discovery of nuclear energy.” The energetic paintings of the Italian Spatial Movement were, according to Time, “almost as explosive as the bomb itself.” “Explosiveness” was a defining feature of much 1950s art, whose main impulse, gestural abstraction, has previously been understood as the urgent expression of the artist's subjectivity. This paper argues that explosiveness in art can also be seen as an “expression” of the realities of the nuclear era. Postwar artists were ambivalent about the explosive forces, both liberating and devastating, that lay within the atom. Toward the end of the 1950s, no longer content merely to represent atomic disintegration, some artists went so far as to propose the outright self-destruction of the work of art as the only fitting means of expression in the atomic age.One must – and this is not an exaggeration – keep in mind that we are living in the atomic age, where everything material and physical could disappear from one day to another, to be replaced by nothing but the ultimate abstraction imaginable.– Yves Klein 1958 (Klein 1973, 10)

Szilard’s Inventions Patently Halted

Valentine L. Telegdi wonders (Physics Today, October 2000, page 25) why Leo Szilard abandoned his early patent applications on the linear accelerator, cyclotron, betatron and synchrocyclotron. Perhaps, he suggests, Szilard “lost interest in pursuing them,” or the patent examiners “may have raised questions of novelty” if they knew the work of Gustaf Ising or others.This has been one of the mysteries of Szilard’s life. Why did he seemingly abandon so many astonishing and career-making inventions? Was it erratic and eccentric behavior, as is usually assumed?In my talk at the Szilard Centenary in Budapest in 1998, 1 1. G. Dannen, http://www.dannen.com/budatalk.html. I argued just the opposite—that Szilard was a logical and determined man who has been misjudged. I published an account of his refrigeration inventions with Albert Einstein, 2 2. G. Dannen, Sci. Am., January 1997, p. https://doi.org/10.1038/scientificamerican0197-90 and I am grateful to Telegdi for this occasion to discuss Szilard’s accelerators.The German patent examiner’s response to Szilard’s 1928 application on the linear accelerator still exists. Szilard gave a copy to Einstein, and it is preserved in the Einstein Archives. The examiner rejected the invention as unpatentable with this classic statement: Patents can be given only for inventions that permit a commercial use. However, the submitted procedure apparently has only a scientific value. Whether, in accordance with the invention, any commercially useful material can be produced by accelerating artificially-produced positively-charged corpuscles, appears from our present knowledge ruled out. In the whole application, no hint is found that the applicant has produced, or can produce, such material. Obviously the yield would be so tiny, as with atomic disintegration from the natural alpha rays of radioactive substances, that even in the future the prospect of using the invention in commerce has the highest degree of improbability. 3 3. Reichspatentamt [German patent office] to L. Szilard, 27 February 1929, document no. 35–611 p. 11. (The Albert Einstein Archives, Jewish National and University Library, Hebrew University of Jerusalem, Israel; Albert Einstein Duplicate Archive, Department of Rare Books and Special Collections, Princeton University Libraries.) Trans. G. Dannen, M. Healy. Priceless! What was Szilard to do? To prove the patent office wrong, he needed to build the devices. But without a patent, what company would support such a project? Szilard turned to his friend Dennis Gabor, as Szilard recalled in an unpublished letter: It was my intention to build some of the machines and I turned over my patent applications to a colleague, Dr. D. Gabor, who at that time was with the Siemens Company and who thought that he might enlist the support of that company for this task. Nothing came of this, however. 4 4. L. Szilard to W. B. Mann, 27 February 1952, box 19, folder 13, Leo Szilard Papers (MSS 0032). (Mandeville Special Collections Library, University of California, San Diego.) Szilard could have stopped there, but he did not. Telegdi notes that in 1934, after fleeing Germany, Szilard filed an application in the UK on betatron and synchrocyclotron designs that were even more sophisticated. Telegdi suggests that this was Szilard’s last work on accelerators, but that is not so.At Oxford University, while searching for an element that might sustain a nuclear chain reaction, Szilard collaborated with James Tuck to build such a betatron. Frederick Lindemann, director of Oxford’s Clarendon Laboratory, agreed to fund betatron construction, and plans were moving forward when history intervened. Donald Kerst, who built the first successful betatron, later called the Szilard–Tuck design the “most promising and most complete in technical detail” of early designs. Kerst believed it “would surely have succeeded were it not for the war in Europe.” 5 5. D. W. Kerst, Nature 157, 94 (1946) https://doi.org/10.1038/157090a0. REFERENCESSection:ChooseTop of pageREFERENCES <<CITING ARTICLES1. G. Dannen, http://www.dannen.com/budatalk.html. Google Scholar2. G. Dannen, Sci. Am., January 1997, p. https://doi.org/10.1038/scientificamerican0197-90 , Google ScholarCrossref, ISI3. Reichspatentamt [German patent office] to L. Szilard, 27 February 1929, document no. 35–611 p. 11. (The Albert Einstein Archives, Jewish National and University Library, Hebrew University of Jerusalem, Israel; Google ScholarAlbert Einstein Duplicate Archive, Department of Rare Books and Special Collections, Princeton University Libraries.) Trans. G. Dannen, M. Healy. Google Scholar4. L. Szilard to W. B. Mann, 27 February 1952, box 19, folder 13, Leo Szilard Papers (MSS 0032). (Mandeville Special Collections Library, University of California, San Diego.) Google Scholar5. D. W. Kerst, Nature 157, 94 (1946) https://doi.org/10.1038/157090a0. Google ScholarCrossref, ISI© 2001 American Institute of Physics.

Soddy at Oxford

Frederick Soddy's productive pure research ended with the outbreak of World War I. Before that time Soddy was internationally acknowledged as a great scientist. He had, with Rutherford, produced the atomic disintegration theory and, in association with Ramsay, had proved it experimentally. He had been one of the first men to elucidate the nature of isotopes, and it was he who gave them their name. After the war he was dismissed as a man who had forsaken his science to propound wild theories of monetary reform.