Luminescence of Molecular Nitrogen and Molecular Oxygen in the Earth’s Middle Atmosphere During the Precipitation of High-Energy Protons

2021 ◽  
Vol 61 (6) ◽  
pp. 864-870
Author(s):  
A. S. Kirillov ◽  
V. B. Belakhovsky ◽  
E. A. Maurchev ◽  
Yu. V. Balabin ◽  
A. V. Germanenko ◽  
...  
Keyword(s):  
Molecular Oxygen ◽  
Middle Atmosphere ◽  
Molecular Nitrogen ◽  
High Energy

scholarly journals The simulation of vibrational populations of electronically excited N2and O2molecules in the middle atmosphere of the Earth during precipitations of high-energetic particles.

2020 ◽  
Author(s):  
A.S. Kirillov ◽  
◽  
R. Werner ◽  
V. Guineva ◽  
◽  
...  
Keyword(s):  
Molecular Oxygen ◽  
Electronic Excitation ◽  
Middle Atmosphere ◽  
Molecular Nitrogen ◽  
Inelastic Collisions ◽  
Transfer Processes ◽  
The Earth ◽  
Electronically Excited ◽  
Kinetics Of

We study the electronic kinetics of molecular nitrogen and molecular oxygen in the middle atmosphere of the Earth during precipitations of high-energetic protons and electrons.The role of molecular inelastic collisions in intermolecularelectron energy transfer processes is investigated.It is shown that inelastic molecular collisions influence on vibrational populations of electronically excited molecular oxygen. It is pointed out on very important role of the collisions of N2(A3u+) with O2molecules on the electronic excitation of Herzberg states of molecular oxygenat the altitudes of the middle atmosphere.

scholarly journals Polar Middle Atmospheric Responses to Medium Energy Electron (MEE) Precipitation Using Numerical Model Simulations

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 133
Author(s):  
Ji-Hee Lee ◽  
Geonhwa Jee ◽  
Young-Sil Kwak ◽  
Heejin Hwang ◽  
Annika Seppälä ◽  
...  
Keyword(s):  
Climate Model ◽  
Middle Atmosphere ◽  
Meridional Circulation ◽  
Stratospheric Ozone ◽  
High Energy ◽  
Chemical Changes ◽  
Temperature Changes ◽  
Mesospheric Temperature ◽  
High Energy Electrons ◽  
Circulation Changes

Energetic particle precipitation (EPP) is known to be an important source of chemical changes in the polar middle atmosphere in winter. Recent modeling studies further suggest that chemical changes induced by EPP can also cause dynamic changes in the middle atmosphere. In this study, we investigated the atmospheric responses to the precipitation of medium-to-high energy electrons (MEEs) over the period 2005–2013 using the Specific Dynamics Whole Atmosphere Community Climate Model (SD-WACCM). Our results show that the MEE precipitation significantly increases the amounts of NOx and HOx, resulting in mesospheric and stratospheric ozone losses by up to 60% and 25% respectively during polar winter. The MEE-induced ozone loss generally increases the temperature in the lower mesosphere but decreases the temperature in the upper mesosphere with large year-to-year variability, not only by radiative effects but also by adiabatic effects. The adiabatic effects by meridional circulation changes may be dominant for the mesospheric temperature changes. In particular, the meridional circulation changes occasionally act in opposite ways to vary the temperature in terms of height variations, especially at around the solar minimum period with low geomagnetic activity, which cancels out the temperature changes to make the average small in the polar mesosphere for the 9-year period.

scholarly journals Middle atmosphere response to the solar cycle in irradiance and ionizing particle precipitation

2011 ◽  
Vol 11 (10) ◽  
pp. 5045-5077 ◽  
Author(s):  
K. Semeniuk ◽  
V. I. Fomichev ◽  
J. C. McConnell ◽  
C. Fu ◽  
S. M. L. Melo ◽  
...  
Keyword(s):  
Solar Cycle ◽  
Radiative Forcing ◽  
Climate Model ◽  
Middle Atmosphere ◽  
High Energy ◽  
Galactic Cosmic Rays ◽  
Particle Precipitation ◽  
Solar Cycle Variation ◽  
Cycle Variation ◽  
The Impact

Abstract. The impact of NOx and HOx production by three types of energetic particle precipitation (EPP), auroral zone medium and high energy electrons, solar proton events and galactic cosmic rays on the middle atmosphere is examined using a chemistry climate model. This process study uses ensemble simulations forced by transient EPP derived from observations with one-year repeating sea surface temperatures and fixed chemical boundary conditions for cases with and without solar cycle in irradiance. Our model results show a wintertime polar stratosphere ozone reduction of between 3 and 10 % in agreement with previous studies. EPP is found to modulate the radiative solar cycle effect in the middle atmosphere in a significant way, bringing temperature and ozone variations closer to observed patterns. The Southern Hemisphere polar vortex undergoes an intensification from solar minimum to solar maximum instead of a weakening. This changes the solar cycle variation of the Brewer-Dobson circulation, with a weakening during solar maxima compared to solar minima. In response, the tropical tropopause temperature manifests a statistically significant solar cycle variation resulting in about 4 % more water vapour transported into the lower tropical stratosphere during solar maxima compared to solar minima. This has implications for surface temperature variation due to the associated change in radiative forcing.

scholarly journals The emission of the negative system of nitrogen from the upper atmosphere and the significance of the twilight flash in the theory of the ionosphere

1949 ◽  
Vol 196 (1047) ◽  
pp. 562-591 ◽  
Keyword(s):  
Transition Probability ◽  
Molecular Nitrogen ◽  
Charged Particles ◽  
High Energy ◽  
Upper Atmosphere ◽  
Ionization Mechanisms ◽  
Direct Excitation ◽  
Negative Band ◽  
Resonance Emission ◽  
Excitation Mechanisms

The cause of the emission of the negative band system of nitrogen from the upper atmosphere during twilight is investigated. A study is made of the two possible excitation mechanisms, N 2 ( X 1 Ʃ g + ) + hv →N 2 + ( B 2 Ʃ u + ) + e and N 2 + ( X 2 Ʃ g + ) + hv →N 2 + ( B 2 Ʃ u + ). It is shown that the latter is far more effective than the former, irrespective of the assumptions adopted regarding the solar flux in the unobservable spectral region. From the transition probability associated with it (which is evaluated in the appendix) combined with various intensity estimates, an upper limit is obtained for the number of N 2 + ions normally present in the E and F layers during twilight. It appears that N 2 + ions form but a minute fraction of the total ion content. The significance of this in the theory of the formation of the ionized layers is discussed. The simplest interpretation is that ionization of molecular nitrogen is unimportant; and a reasonable scheme that invokes only the ionization of oxygen atoms and molecules is available. However, by introducing certain arbitrary assumptions a more elaborate interpretation is conceivable so that the view that the E layer arises from the action of high-energy coronal photons, which ionize all atmospheric constituents, cannot be finally rejected. Various aspects of the layers are discussed, and observational and experimental work, which might yield evidence on the ionization mechanisms operative, is suggested. It is pointed out that the remarkable rarity of N 2 + ions proves conclusively that recombination between the charged particles present in the ionosphere cannot be the origin of the nocturnal radiation of the nitrogen band systems. On some occasions the resonance emission at twilight is of unusually high intensity. It is presumed that this is due to incident charged particles increasing the concentration of N 2 + ions. The possible contribution that these charged particles may make to the night-sky light by direct excitation collisions is briefly examined. Sunlit aurorae (which are essentially similar to the twilight flash) are also discussed.

Chronic Granulomatous Disease and Pneumocystis carinii Pneumonia

PEDIATRICS ◽  
1982 ◽  
Vol 69 (1) ◽  
pp. 133-134
Author(s):  
Allen D. Adinoff ◽  
Richard B. Johnston ◽  
Jale Dolen ◽  
Mary Ann South
Keyword(s):  
Chronic Granulomatous Disease ◽  
Molecular Oxygen ◽  
Pneumocystis Carinii Pneumonia ◽  
Pneumocystis Carinii ◽  
Enteric Bacteria ◽  
High Energy ◽  
Granulomatous Disease ◽  
Energy Metabolites

Chronic granulomatous disease (CGD) is a syndrome characterized by recurrent purulent infections of the skin, lungs, and reticuloendothelial organs. The underlying defect is an inability of phagocytes to convert molecular oxygen into high-energy metabolites that contribute to microbial death. Infections are primarily due to staphylococci, enteric bacteria, fungi, and occasionally mycobacteria.1 An 11-year-old girl with CGD was reported to have pneumonia due to P carinii.2 We have found a second case of CGD with pneumonia due to P carinii.

scholarly journals Mechanism of the Formation of Electronically Excited Species by Oxidative Metabolic Processes: Role of Reactive Oxygen Species

Biomolecules ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 258 ◽  
Author(s):  
Pavel Pospíšil ◽  
Ankush Prasad ◽  
Marek Rác
Keyword(s):  
Reactive Oxygen Species ◽  
Molecular Oxygen ◽  
Reactive Oxygen ◽  
High Energy ◽  
Oxygen Species ◽  
Human Beings ◽  
Metabolic Processes ◽  
Excited Species ◽  
Electronically Excited

It is well known that biological systems, such as microorganisms, plants, and animals, including human beings, form spontaneous electronically excited species through oxidative metabolic processes. Though the mechanism responsible for the formation of electronically excited species is still not clearly understood, several lines of evidence suggest that reactive oxygen species (ROS) are involved in the formation of electronically excited species. This review attempts to describe the role of ROS in the formation of electronically excited species during oxidative metabolic processes. Briefly, the oxidation of biomolecules, such as lipids, proteins, and nucleic acids by ROS initiates a cascade of reactions that leads to the formation of triplet excited carbonyls formed by the decomposition of cyclic (1,2-dioxetane) and linear (tetroxide) high-energy intermediates. When chromophores are in proximity to triplet excited carbonyls, the triplet-singlet and triplet-triplet energy transfers from triplet excited carbonyls to chromophores result in the formation of singlet and triplet excited chromophores, respectively. Alternatively, when molecular oxygen is present, the triplet-singlet energy transfer from triplet excited carbonyls to molecular oxygen initiates the formation of singlet oxygen. Understanding the mechanism of the formation of electronically excited species allows us to use electronically excited species as a marker for oxidative metabolic processes in cells.

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