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Results for “COSMIC RADIATION”

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PubMed1998

Amino acid formation in gas mixtures by high energy particle irradiation.

Amino acids were formed from carbon monoxide, nitrogen and water, which are possible constituents of the primitive earth's atmosphere, by irradiation with high energy particles (components of cosmic rays). Glycine yield was proportional to the total energy deposited to the gas mixture, and its G-value was as high as 0.02 when the carbon monoxide/nitrogen ratio was 1. Based on an estimate of the effective energies of various types of energy sources available in the primitive earth's atmosphere for amino acid synthesis, it is suggested that cosmic rays were one of the most important energy sources for the synthesis of amino acids on the primitive earth.

Amino Acids↗
PubMed2005

Suicide-homicide temporal interrelationship, links with other fatalities, and environmental physical activity.

UNLABELLED: Homicide and suicide are extremes in human behavior. The aim of this study is to investigate the connection by time between suicide and homicide, between them and other fatalities, and their links with the level of cosmophysical activity. METHODS: Using the national database of Lithuania (1990-2002) we found that 547,875 deaths, 4,638 homicides (3,374 male) and 19,527 (16,019 male) suicides were registered in that period. Their temporal distribution over 156 months was compared with solar and cosmic-ray activity. Pearson correlation coefficients and their probabilities were established. RESULTS: There was a correlation between monthly rates of homicide and male groups. Female suicide rates correlated with male and total homicide numbers. Both homicide and suicide rates were inversely correlated with solar and cosmic-ray activity. Suicide numbers, but not homicides, were inversely related to geomagnetic activity. Suicide rates were inversely correlated with total, cardiovascular, traffic accident, and sudden deaths; homicide with total, traffic accident, and sudden deaths. CONCLUSION: Temporal distribution of homicide and suicide is significantly interrelated. Both are linked to parameters of cosmophysical activity. The influence of cosmic rays deserves special attention.

Cosmic Radiation↗
PubMed2000

Characterizing the nonlinear growth of large-scale structure in the Universe

The local Universe displays a rich hierarchical pattern of galaxy clusters and superclusters. The early Universe, however, was almost smooth, with only slight 'ripples' as seen in the cosmic microwave background radiation. Models of the evolution of cosmic structure link these observations through the effect of gravity, because the small initially overdense fluctuations are predicted to attract additional mass as the Universe expands. During the early stages of this expansion, the ripples evolve independently, like linear waves on the surface of deep water. As the structures grow in mass, they interact with each other in nonlinear ways, more like waves breaking in shallow water. We have recently shown how cosmic structure can be characterized by phase correlations associated with these nonlinear interactions, but it was not clear how to use that information to obtain quantitative insights into the growth of structures. Here we report a method of revealing phase information, and show quantitatively how this relates to the formation of filaments, sheets and clusters of galaxies by nonlinear collapse. We develop a statistical method based on information entropy to separate linear from nonlinear effects, and thereby are able to disentangle those aspects of galaxy clustering that arise from initial conditions (the ripples) from the subsequent dynamical evolution.

Journal Article↗
PubMed2005

Astrophysics: is a doomsday catastrophe likely?

The risk of a doomsday scenario in which high-energy physics experiments trigger the destruction of the Earth has been estimated to be minuscule. But this may give a false sense of security: the fact that the Earth has survived for so long does not necessarily mean that such disasters are unlikely, because observers are, by definition, in places that have avoided destruction. Here we derive a new upper bound of one per billion years (99.9% confidence level) for the exogenous terminal-catastrophe rate that is free of such selection bias, using calculations based on the relatively late formation time of Earth.

Cosmic Radiation↗
PubMed2003

A median redshift of 2.4 for galaxies bright at submillimetre wavelengths.

A significant fraction of the energy emitted in the early Universe came from very luminous galaxies that are largely hidden at optical wavelengths (because of interstellar dust grains); this energy now forms part of the cosmic background radiation at wavelengths near 1 mm (ref. 1). Some submillimetre (submm) galaxies have been resolved from the background radiation, but they have been difficult to study because of instrumental limitations. This has impeded the determination of their redshifts (z), which is a crucial element in understanding their nature and evolution. Here we report spectroscopic redshifts for ten submm galaxies that were identified using high-resolution radio observations. The median redshift for our sample is 2.4, with a quartile range of 1.9-2.8. This population therefore coexists with the peak activity of quasars, suggesting a close relationship between the growth of massive black holes and luminous dusty galaxies. The space density of submm galaxies at redshifts over 2 is about 1,000 times greater than that of similarly luminous galaxies in the present-day Universe, so they represent an important component of star formation at high redshifts.

Journal Article↗
PubMed1994

The evolution of the universe.

Some 15 billion years ago the universe emerged from a hot, dense sea of matter and energy. As the cosmos expanded and cooled, it spawned galaxies, stars, planets and life.

Astronomical Phenomena↗