Equatorial secondary cosmic ray observatory to study space weather and terrestrial events

Science.gov (United States)

Vichare, Geeta; Bhaskar, Ankush; Datar, Gauri; Raghav, Anil; Nair, K. U.; Selvaraj, C.; Ananthi, M.; Sinha, A. K.; Paranjape, M.; Gawade, T.; Anil Kumar, C. P.; Panneerselvam, C.; Sathishkumar, S.; Gurubaran, S.

2018-05-01

Recently, equatorial secondary cosmic ray observatory has been established at Equatorial Geophysical Research Laboratory (EGRL), Tirunelveli, (Geographic Coordinates: 8.71°N, 77.76°E), to study secondary cosmic rays (SCR) produced due to the interaction of primary cosmic rays with the Earth's atmosphere. EGRL is a regional center of Indian Institute of Geomagnetism (IIG), located near the equator in the Southern part of India. Two NaI(Tl) scintillation detectors are installed inside the temperature controlled environment. One detector is cylindrical in shape of size 7.62 cm × 7.62 cm and another one is rectangular cuboid of 10.16 cm × 10.16 cm × 40.64 cm size. Besides NaI(Tl) detectors, various other research facilities such as the Geomagnetic observatory, Medium Frequency Radar System, Digital Ionosonde, All-sky airglow imager, Atmospheric electricity laboratory to measure the near-Earth atmospheric electric fields are also available at EGRL. With the accessibility of multi- instrument facilities, the objective is set to understand the relationship between SCR and various atmospheric and ionospheric processes, during space weather and terrestrial events. For gamma-ray spectroscopy, it is important to test the performance of the NaI(Tl) scintillation detectors and to calibrate the gamma-ray spectrum in terms of energy. The present article describes the details of the experimental setup installed near the equator to study cosmic rays, along with the performance testing and calibration of the detectors under various conditions. A systematic shift in the gain is observed with varying temperature of the detector system. It is found that the detector's response to the variations in the temperature is not just linear or non-linear type, but it depends on the history of the variation, indicating temperature hysteresis effects on NaI detector and PMT system. This signifies the importance of isothermal environment while studying SCR flux using NaI(Tl) detectors

Cosmic Explosions, Life in the Universe, and the Cosmological Constant

Science.gov (United States)

Piran, Tsvi; Jimenez, Raul; Cuesta, Antonio J.; Simpson, Fergus; Verde, Licia

2016-02-01

Gamma-ray bursts (GRBs) are copious sources of gamma rays whose interaction with a planetary atmosphere can pose a threat to complex life. Using recent determinations of their rate and probability of causing massive extinction, we explore what types of universes are most likely to harbor advanced forms of life. We use cosmological N -body simulations to determine at what time and for what value of the cosmological constant (Λ ) the chances of life being unaffected by cosmic explosions are maximized. Life survival to GRBs favors Lambda-dominated universes. Within a cold dark matter model with a cosmological constant, the likelihood of life survival to GRBs is governed by the value of Λ and the age of the Universe. We find that we seem to live in a favorable point in this parameter space that minimizes the exposure to cosmic explosions, yet maximizes the number of main sequence (hydrogen-burning) stars around which advanced life forms can exist.

Cosmic Explosions, Life in the Universe, and the Cosmological Constant.

Science.gov (United States)

Piran, Tsvi; Jimenez, Raul; Cuesta, Antonio J; Simpson, Fergus; Verde, Licia

2016-02-26

Gamma-ray bursts (GRBs) are copious sources of gamma rays whose interaction with a planetary atmosphere can pose a threat to complex life. Using recent determinations of their rate and probability of causing massive extinction, we explore what types of universes are most likely to harbor advanced forms of life. We use cosmological N-body simulations to determine at what time and for what value of the cosmological constant (Λ) the chances of life being unaffected by cosmic explosions are maximized. Life survival to GRBs favors Lambda-dominated universes. Within a cold dark matter model with a cosmological constant, the likelihood of life survival to GRBs is governed by the value of Λ and the age of the Universe. We find that we seem to live in a favorable point in this parameter space that minimizes the exposure to cosmic explosions, yet maximizes the number of main sequence (hydrogen-burning) stars around which advanced life forms can exist.

Evolution of matter and energy on a cosmic and planetary scale

International Nuclear Information System (INIS)

Taube, M.

1985-01-01

This book covers the following topics: matter and energy; the interplay of elementary particles and elementary forces; the universe; how is it observed here and now; its past and possible future; the origin and nuclear evolution of matter; chemical evolution and the evolution of life; the cosmic phenomena; the eternal cycle of matter on the earth; the flow of energy on the earth; the biosphere; the coupling of matter and the flow of free energy; is the future development of mankind on this planet possible, and the distant future of mankind: terrestrial or cosmic

The beginnings of life as a cosmic phenomenon

Science.gov (United States)

Wickramasinghe, N. C.

2015-09-01

The emerging consensus that comets carry the biochemical seeds of life coincides with the first step that was reached as early as 1977 in the historical development of the Hoyle-Wickramasinghe theory of cosmic life. To mark the centenary of the birth of Sir Fred Hoyle on 24 June 2015 this brief article retraces early developments that essentially heralded the new science of astrobiology.

DNA Sequencing and Predictions of the Cosmic Theory of Life

Science.gov (United States)

Wickramasinghe, N. Chandra

The theory of cometary panspermia, developed by the late Sir Fred Hoyle and the present author argues that life originated cosmically as a unique event in one of a great multitude of comets or planetary bodies in the Universe. Life on Earth did not originate here but was introduced by impacting comets, and its further evolution was driven by the subsequent acquisition of cosmically derived genes. Explicit predictions of this theory published in 1979-1981, stating how the acquisition of new genes drives evolution, are compared with recent developments in relation to horizontal gene transfer, and the role of retroviruses in evolution. Precisely-stated predictions of the theory of cometary panspermia are shown to have been verified.

Analytical Model for Estimating Terrestrial Cosmic Ray Fluxes Nearly Anytime and Anywhere in the World: Extension of PARMA/EXPACS.

Directory of Open Access Journals (Sweden)

Tatsuhiko Sato

Full Text Available By extending our previously established model, here we present a new model called "PHITS-based Analytical Radiation Model in the Atmosphere (PARMA version 3.0," which can instantaneously estimate terrestrial cosmic ray fluxes of neutrons, protons, ions with charge up to 28 (Ni, muons, electrons, positrons, and photons nearly anytime and anywhere in the Earth's atmosphere. The model comprises numerous analytical functions with parameters whose numerical values were fitted to reproduce the results of the extensive air shower (EAS simulation performed by Particle and Heavy Ion Transport code System (PHITS. The accuracy of the EAS simulation was well verified using various experimental data, while that of PARMA3.0 was confirmed by the high R2 values of the fit. The models to be used for estimating radiation doses due to cosmic ray exposure, cosmic ray induced ionization rates, and count rates of neutron monitors were validated by investigating their capability to reproduce those quantities measured under various conditions. PARMA3.0 is available freely and is easy to use, as implemented in an open-access software program EXcel-based Program for Calculating Atmospheric Cosmic ray Spectrum (EXPACS. Because of these features, the new version of PARMA/EXPACS can be an important tool in various research fields such as geosciences, cosmic ray physics, and radiation research.

Generation of terrestrial radiation database in the Larsemann Hills, Antarctica

International Nuclear Information System (INIS)

Pal, Rupali; Dhabekar, Bhushan; Jose, Jis Romal; Chinnaesakki, S.; Bakshi, A.K.; Datta, D.; Pradeepkumar, K.S.

2018-01-01

Natural background radiation in the environment includes terrestrial radiation, cosmic radiation from space and air activity due to radon/thoron. It is known that cosmic contribution increases near the poles. The terrestrial component is largely due to 232 Th and 238 U series and 40 K. BARC under the cosmic ray dosimetry project with National Centre for Antarctic and Ocean Research (NCAOR) has taken up measurement of natural background radiation at Larsemann Hills, Antarctica. The project includes generation of baseline data on terrestrial radioactivity in water, soil and rock and estimation of cosmic ray doses. Extensive radiation surveys were carried out by the BARC team in the 35 th and 36 th expedition in and around Larsemann hills in East Antarctica where the third Indian station 'Bharati' is situated. This paper presents mapping of terrestrial radiation levels in Antarctica which will help in strengthening the background radiation database and develop a Radiation Informatics System (RIS)

The beta(+) decay and cosmic-ray half-life of Mn-54

Science.gov (United States)

Dacruz, M. T. F.; Norman, E. B.; Chan, Y. D.; Garcia, A.; Larimer, R. M.; Lesko, K. T.; Stokstad, R. G.; Wietfeldt, F. E.

1993-03-01

We performed a search for the beta(+) branch of Mn-54 decay. As a cosmic ray, Mn-54, deprived of its atomic electrons, can decay only via beta(+) and beta(-) decay, with a half-life of the order of 106 yr. This turns Mn-54 into a suitable cosmic chronometer for the study of cosmic-ray confinement times. We searched for coincident back-to-back 511-keV gamma-rays using two germanium detectors inside a Nal(Tl) annulus. An upper limit of 2 x 10-8 was found for the beta(+) decay branch, corresponding to a lower limit of 13.7 for the log ft value.

A cosmic microwave background feature consistent with a cosmic texture.

Science.gov (United States)

Cruz, M; Turok, N; Vielva, P; Martínez-González, E; Hobson, M

2007-12-07

The Cosmic Microwave Background provides our most ancient image of the universe and our best tool for studying its early evolution. Theories of high-energy physics predict the formation of various types of topological defects in the very early universe, including cosmic texture, which would generate hot and cold spots in the Cosmic Microwave Background. We show through a Bayesian statistical analysis that the most prominent 5 degrees -radius cold spot observed in all-sky images, which is otherwise hard to explain, is compatible with having being caused by a texture. From this model, we constrain the fundamental symmetry-breaking energy scale to be (0) approximately 8.7 x 10(15) gigaelectron volts. If confirmed, this detection of a cosmic defect will probe physics at energies exceeding any conceivable terrestrial experiment.

On the possibility of galactic cosmic ray-induced radiolysis-powered life in subsurface environments in the Universe.

Science.gov (United States)

Atri, Dimitra

2016-10-01

Photosynthesis is a mechanism developed by terrestrial life to utilize the energy from photons of solar origin for biological use. Subsurface regions are isolated from the photosphere, and consequently are incapable of utilizing this energy. This opens up the opportunity for life to evolve alternative mechanisms for harvesting available energy. Bacterium Candidatus Desulforudis audaxviator, found 2.8 km deep in a South African mine, harvests energy from radiolysis, induced by particles emitted from radioactive U, Th and K present in surrounding rock. Another radiation source in the subsurface environments is secondary particles generated by galactic cosmic rays (GCRs). Using Monte Carlo simulations, it is shown that it is a steady source of energy comparable to that produced by radioactive substances, and the possibility of a slow metabolizing life flourishing on it cannot be ruled out. Two mechanisms are proposed through which GCR-induced secondary particles can be utilized for biological use in subsurface environments: (i) GCRs injecting energy in the environment through particle-induced radiolysis and (ii) organic synthesis from GCR secondaries interacting with the medium. Laboratory experiments to test these hypotheses are also proposed. Implications of these mechanisms on finding life in the Solar System and elsewhere in the Universe are discussed. © 2016 The Author(s).

Life as a Cosmic Phenomenon: 2. the Panspermic Trajectory of Homo Sapiens

Science.gov (United States)

Tokoro, Gensuke; Wickramasinghe, N. Chandra

We discuss the origin and evolution of Homo sapiens in a cosmic context, and in relation to the Hoyle-Wickramasinghe theory of panspermia for which there is now overwhelming evidence. It is argued that the first bacteria (archea) incident on the Earth via the agency of comets 3.8-4 billion years ago continued at later times to be augmented by viral genes (DNA, RNA) from space that eventually led to the evolutionary patterns we see in present-day biology. We argue that the current evolutionary status of Homo sapiens as well as its future trajectory is circumscribed by evolutionary processes that were pre-determined on a cosmic scale -- over vast distances and enormous spans of cosmic time. Based on this teleological hypothesis we postulate that two distinct classes of cosmic viruses (cosmic viral genes) are involved in accounting for the facts relating to the evolution of life.

Amphibians at risk? Susceptibility of terrestrial amphibian life stages to pesticides.

Science.gov (United States)

Brühl, Carsten A; Pieper, Silvia; Weber, Brigitte

2011-11-01

Current pesticide risk assessment does not specifically consider amphibians. Amphibians in the aquatic environment (aquatic life stages or postmetamorphic aquatic amphibians) and terrestrial living juvenile or adult amphibians are assumed to be covered by the risk assessment for aquatic invertebrates and fish, or mammals and birds, respectively. This procedure has been evaluated as being sufficiently protective regarding the acute risk posed by a number of pesticides to aquatic amphibian life stages (eggs, larvae). However, it is unknown whether the exposure and sensitivity of terrestrial living amphibians are comparable to mammalian and avian exposure and sensitivity. We reviewed the literature on dermal pesticide absorption and toxicity studies for terrestrial life stages of amphibians, focusing on the dermal exposure pathway, that is, through treated soil or direct overspray. In vitro studies demonstrated that cutaneous absorption of chemicals is significant and that chemical percutaneous passage, P (cm/h), is higher in amphibians than in mammals. In vivo, the rapid and substantial uptake of the herbicide atrazine from treated soil by toads (Bufo americanus) has been described. Severe toxic effects on various amphibian species have been reported for field-relevant application rates of different pesticides. In general, exposure and toxicity studies for terrestrial amphibian life stages are scarce, and the reported data indicate the need for further research, especially in light of the global amphibian decline. Copyright © 2011 SETAC.

Radionuclide biological half-life values for terrestrial and aquatic wildlife

International Nuclear Information System (INIS)

Beresford, N.A.; Beaugelin-Seiller, K.; Burgos, J.; Cujic, M.; Fesenko, S.; Kryshev, A.; Pachal, N.; Real, A.; Su, B.S.; Tagami, K.; Vives i Batlle, J.; Vives-Lynch, S.; Wells, C.; Wood, M.D.

2015-01-01

The equilibrium concentration ratio is typically the parameter used to estimate organism activity concentrations within wildlife dose assessment tools. Whilst this is assumed to be fit for purpose, there are scenarios such as accidental or irregular, fluctuating, releases from licensed facilities when this might not be the case. In such circumstances, the concentration ratio approach may under- or over-estimate radiation exposure depending upon the time since the release. To carrying out assessments for such releases, a dynamic approach is needed. The simplest and most practical option is representing the uptake and turnover processes by first-order kinetics, for which organism- and element-specific biological half-life data are required. In this paper we describe the development of a freely available international database of radionuclide biological half-life values. The database includes 1907 entries for terrestrial, freshwater, riparian and marine organisms. Biological half-life values are reported for 52 elements across a range of wildlife groups (marine = 9, freshwater = 10, terrestrial = 7 and riparian = 3 groups). Potential applications and limitations of the database are discussed. - Highlights: • 1907 biological half-life values have been collated for wildlife species. • Data cover 52 elements. • 27 marine, freshwater, riparian and terrestrial organisms are included.

Bryophyte in the Beginning of Terrestrial Life

Directory of Open Access Journals (Sweden)

Özcan ŞİMŞEK

2016-12-01

Full Text Available The beginning of life has been wondered by human beings since ancient ages. The widely accepted opinion is that life began in water and after that landed. In this process, the landing of plants and adapting to terrestrial life of plants are important stages. The last 20 years it’s been done many researches to find out the relationship of bryophytes and tracheophytes. The results of these researches revealed that in evolutionary development process bryophytes and tracheophytes are sister groups. Thesis about earliest land plants are bryophytes is widely accepted recent years. To understand evolutionary process and plants of today’s better, researches about bryophytes must increase.

Study of cosmic rays reveals secrets of solar-terrestrial science

Science.gov (United States)

Jokipii, J. R.

For many years cosmic rays provided the most important source of energetic particles for studies of subatomic physics. Today, cosmic rays are being studied as a natural phenomenon that can tell us much about both the Earth's environment in space and distant astrophysical processes. Cosmic rays are naturally occurring energetic particles—mainly ions—with kinetic energies extending from just above thermal energies to more than 1020 electron volts (eV). They constantly bombard the Earth from all directions, with more than 1018 particles having energies >1 MeV striking the top of the Earth's atmosphere each second. Figure 1 illustrates the continuous cosmic ray energy spectrum.

Risk assessment considerations for plant protection products and terrestrial life-stages of amphibians.

Science.gov (United States)

Weltje, Lennart; Ufer, Andreas; Hamer, Mick; Sowig, Peter; Demmig, Sandra; Dechet, Friedrich

2018-04-28

Some amphibians occur in agricultural landscapes during certain periods of their life cycle and consequently might be exposed to plant protection products (PPPs). While the sensitivity of aquatic life-stages is considered to be covered by the standard assessment for aquatic organisms (especially fish), the situation is less clear for terrestrial amphibian life-stages. In this paper, considerations are presented on how a risk assessment for PPPs and terrestrial life-stages of amphibians could be conducted. It discusses available information concerning the toxicity of PPPs to terrestrial amphibians, and their potential exposure to PPPs in consideration of aspects of amphibian biology. The emphasis is on avoiding additional vertebrate testing as much as possible by using exposure-driven approaches and by making use of existing vertebrate toxicity data, where appropriate. Options for toxicity testing and risk assessment are presented in a flowchart as a tiered approach, progressing from a non-testing approach, to simple worst-case laboratory testing, to extended laboratory testing, to semi-field enclosure tests and ultimately to full-scale field testing and monitoring. Suggestions are made for triggers to progress to higher tiers. Also, mitigation options to reduce the potential for exposure of terrestrial life-stages of amphibians to PPPs, if a risk were identified, are discussed. Finally, remaining uncertainties and research needs are considered by proposing a way forward (road map) for generating additional information to inform terrestrial amphibian risk assessment. Copyright © 2018 Elsevier B.V. All rights reserved.

High efficiency, long life terrestrial solar panel

Science.gov (United States)

Chao, T.; Khemthong, S.; Ling, R.; Olah, S.

1977-01-01

The design of a high efficiency, long life terrestrial module was completed. It utilized 256 rectangular, high efficiency solar cells to achieve high packing density and electrical output. Tooling for the fabrication of solar cells was in house and evaluation of the cell performance was begun. Based on the power output analysis, the goal of a 13% efficiency module was achievable.

Proceedings of the 21. European Cosmic Ray Symposium

International Nuclear Information System (INIS)

Kiraly, P.; Kudela, K.; Wolfendale, A. W.

2008-09-01

Scientific symposium deals with problems of cosmic ray. The Symposium included the following sessions: (1): Relationship of cosmic rays to the environment; (2) Energetic particles and the magnetosphere of the Earth; (3) Energetic particles in the heliosphere; (4) Solar-terrestrial effects on different time scales; (5) Cosmic rays below the knee; (6) Cosmic rays above the knee (7) High energy interactions; (8) GeV and TeV gamma ray astronomy; (9) European projects related to cosmic rays; Future perspectives. Proceedings contains 122 papers dealing with the scope of INIS.

Mupasi as cosmic s(Spirit: The universe as a community of life

Directory of Open Access Journals (Sweden)

Kuzipa M.B. Nalwamba

2017-08-01

Full Text Available Mupasi recalls the belief that humans form part of the community of life within the realm of the cosmic spirit. The assertion seems like a truism that requires no further enunciation. However, belief in the Creator-Spirit, a pneuma-theological understanding of creation, is relatively young in the Christian tradition. In Colossians 1:15-20, Christ is presented as instrumental to creation. Christian tradition therefore tends to present creation in Christological terms. The foundational belief in Spirit-Creator-God has not historically undergirded Christian belief about creation. The Christian faith could therefore benefit from ‘companion’ views of creation in terms of the cosmic spirit. Mupasi is understood as cosmic spirit, the axis of the universe apprehended as an organic whole. The web of life was brought into being, is sustained by, and inhabited by Mupasi. This retrieval has continuities and discontinuities with Christian belief as Spirit-Creator-God. It is presented here as a notion that calls the Christian faith back to its originating intuitions about creation. Mupasi is appropriated within a pneuma-theological framework that addressed a pressing issue of our time, the global ecological crisis. Mupasi presents an ecological critique that is meaningful for a renewed appreciation of community beyond an anthropocentric focus. The cosmic relatedness brings a renewed vision of the universe as a cosmic community of the s(Spirit. The cultural and intellectual milieu of Mupasi is undergirded by a relational conception of reality. It provides a critical lens with implications for ecclesiology that challenges the church’s self-understanding and ways of being.

The search for our cosmic ancestry

CERN Document Server

Wickramasinghe, Chandra

2015-01-01

The idea that life is a cosmic, rather than a purely terrestrial phenomenon, has progressed from scientific heresy to mainstream science within the short timespan of a few decades. The theory of cometary panspermia developed by Fred Hoyle and the present author in the 1970's has been vindicated by a spate of new discoveries in astronomy and biology, and also with startling new evidence of microbial fossils in meteorites and micrometeorites. The recent Kepler Telescope searches for exoplanets have indicated the presence of over 100 billion habitable planets separated by only a few light years, thus making panspermia and the transfer of microbial life between such planets an inevitable fact. The book presents a comprehensive and up-to-date account of the Hoyle-Wickramasinghe theory of cometary panspermia in a manner accessible to a wide general readership.

Cosmic Biology How Life Could Evolve on Other Worlds

CERN Document Server

Irwin, Louis Neil

2011-01-01

It is very unlikely that little green humanoids are living on Mars. But what are the possible life forms that might exist in our Solar System and how might they have evolved? This uniquely authoritative and imaginative book on the possibilties for alien life addresses the intrinsic interest that we have about life on other worlds - reinforcing some of our assumptions and reshaping others. It introduces new possibilties that will enlarge our understanding of the issue overall, in particular the enormous range of environments and planetary conditions within which life might evolve. Cosmic Biology -discusses a broad range of possible environments where alien life might have evolved; -explains why carbon-based, water-borne life is more likely that its alternatives, but is not the only possiblity; -applies the principles of planetary science and modern biology to evolutionary scenarios on other worlds; -looks at the future fates of living systems, including those on Earth.

Terrestrial Zone Exoplanets and Life

Science.gov (United States)

Matthews, Brenda

2018-01-01

One of the most exciting results from ALMA has been the detection of significant substructure within protoplanetary disks that can be linked to planet formation processes. For the first time, we are able to observe the process of assembly of material into larger bodies within such disks. It is not possible, however, for ALMA to probe the growth of planets in protoplanetary disks at small radii, i.e., in the terrestrial zone, where we expect rocky terrestrial planets to form. In this regime, the optical depths prohibit observation at the high frequencies observed by ALMA. To probe the effects of planet building processes and detect telltale gaps and signatures of planetary mass bodies at such small separations from the parent star, we require a facility of superior resolution and sensitivity at lower frequencies. The ngVLA is just such a facility. We will present the fundamental science that will be enabled by the ngVLA in protoplanetary disk structure and the formation of planets. In addition, we will discuss the potential for an ngVLA facility to detect the molecules that are the building blocks of life, reaching limits well beyond those reachable with the current generation of telescopes, and also to determine whether such planets will be habitable based on studies of the impact of stars on their nearest planetary neighbours.

Acute oral toxicity of chemicals in terrestrial life stages of amphibians: Comparisons to birds and mammals.

Science.gov (United States)

Crane, Mark; Finnegan, Meaghean; Weltje, Lennart; Kosmala-Grzechnik, Sylwia; Gross, Melanie; Wheeler, James R

2016-10-01

Amphibians are currently the most threatened and rapidly declining group of vertebrates and this has raised concerns about their potential sensitivity and exposure to plant protection products and other chemicals. Current environmental risk assessment procedures rely on surrogate species (e.g. fish and birds) to cover the risk to aquatic and terrestrial life stages of amphibians, respectively. Whilst a recent meta-analysis has shown that in most cases amphibian aquatic life stages are less sensitive to chemicals than fish, little research has been conducted on the comparative sensitivity of terrestrial amphibian life stages. Therefore, in this paper we address the questions "What is the relative sensitivity of terrestrial amphibian life stages to acute chemical oral exposure when compared with mammals and birds?" and "Are there correlations between oral toxicity data for amphibians and data for mammals or birds?" Identifying a relationship between these data may help to avoid additional vertebrate testing. Acute oral amphibian toxicity data collected from the scientific literature and ecotoxicological databases were compared with toxicity data for mammals and birds. Toxicity data for terrestrial amphibian life stages are generally sparse, as noted in previous reviews. Single-dose oral toxicity data for terrestrial amphibian life stages were available for 26 chemicals and these were positively correlated with LD50 values for mammals, while no correlation was found for birds. Further, the data suggest that oral toxicity to terrestrial amphibian life stages is similar to or lower than that for mammals and birds, with a few exceptions. Thus, mammals or birds are considered adequate toxicity surrogates for use in the assessment of the oral exposure route in amphibians. However, there is a need for further data on a wider range of chemicals to explore the wider applicability of the current analyses and recommendations. Copyright © 2016 Elsevier Inc. All rights reserved.

RESPONSE OF THE GREEK EARLY WARNING SYSTEM REUTER-STOKES IONIZATION CHAMBERS TO TERRESTRIAL AND COSMIC RADIATION EVALUATED IN COMPARISON WITH SPECTROSCOPIC DATA AND TIME SERIES ANALYSIS.

Science.gov (United States)

Leontaris, F; Clouvas, A; Xanthos, S; Maltezos, A; Potiriadis, C; Kiriakopoulos, E; Guilhot, J

2018-02-01

The Telemetric Early Warning System Network of the Greek Atomic Energy Commission consists mainly of a network of 24 Reuter-Stokes high-pressure ionization chambers (HPIC) for gamma dose rate measurements and covers all Greece. In the present work, the response of the Reuter-Stokes HPIC to terrestrial and cosmic radiation was evaluated in comparison with spectroscopic data obtained by in situ gamma spectrometry measurements with portable hyper pure Germanium detectors (HPGe), near the Reuter-Stokes detectors and time series analysis. For the HPIC detectors, a conversion factor for the measured absorbed dose rate in air (in nGy h-1) to the total ambient dose equivalent rate Ḣ*(10), due to terrestrial and cosmic component, was deduced by the field measurements. Time series analysis of the mean monthly dose rate (measured by the Reuter-Stokes detector in Thessaloniki, northern Greece, from 2001 to 2016) was performed with advanced statistical methods (Fast Fourier Analysis and Zhao Atlas Marks Transform). Fourier analysis reveals several periodicities (periodogram). The periodogram of the absorbed dose rate in air values was compared with the periodogram of the values measured for the same period (2001-16) and in the same location with a NaI (Tl) detector which in principle is not sensitive to cosmic radiation. The obtained results are presented and discussed. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Radio Astronomy Explorer /RAE/. I - Observations of terrestrial radio noise.

Science.gov (United States)

Herman, J. R.; Caruso, J. A.; Stone, R. G.

1973-01-01

Radio Astronomy Explorer (RAE) I data are analyzed to establish characteristics of HF terrestrial radio noise at an altitude of about 6000 km. Time and frequency variations in amplitude of the observed noise well above cosmic noise background are explained on the basis of temporal and spatial variations in ionospheric critical frequency coupled with those in noise source distributions. It is shown that terrestrial radio noise regularly breaks through the ionosphere and reaches RAE with magnitudes 15 dB and more above cosmic noise background, on frequencies above the F-layer critical frequency.

An estimate of cosmic dose component around Kudankulam site

International Nuclear Information System (INIS)

Vijayakumar, B.; Thomas, G.; Rajan, P.S.; Selvi, B.S.; Balamurugan, M.; Ravi, P.M.; Tripathi, R.M.

2015-01-01

Natural ionizing radiation pervades the whole environment and enters human lives in a wide variety of ways. It arises from natural processes such as the decay of terrestrially deposited radionuclides in the earth, and artificial processes like the use of X-rays in medicine. Thus, radiation can be classified as natural and artificial depending on its origin. Natural sources include cosmic rays, terrestrial gamma radiation, radon and its decay products in air and various radio nuclides found naturally in food and drink. Cosmic rays reach the earth from outer space. Artificial sources include medical X-rays, therapeutic use of radioisotopes, fallout from past weapon tests, discharges from nuclear industry, industrial gamma rays and use of radioisotopes in consumer products. This paper attempts to estimate the natural cosmic dose component around Kudankulam Nuclear Power Plant site in the south eastern coast of India. (author)

Radio Astronomy Explorer (RAE) 1 observations of terrestrial radio noise

Science.gov (United States)

Herman, J. R.; Caruso, J. A.

1971-01-01

Radio Astonomy Explorer (RAE) 1 data are analyzed to establish characteristics of HF terrestrial radio noise at an altitude of about 6000 km. Time and frequency variations in amplitude of the observed noise well above cosmic noise background are explained on the basis of temporal and spatial variations in ionospheric critical frequency coupled with those in noise source distributions. It is shown that terrestrial noise regularly breaks through the ionosphere and reaches RAE with magnitudes 15 or more db higher than cosmic noise background. Maximum terrestrial noise is observed when RAE is over the dark side of the Earth in the neighborhood of equatorial continental land masses where thunderstorms occur most frequently. The observed noise level is 30-40 db lower with RAE over oceans.

Cosmic-ray interactions and dating of meteorite stranding surfaces with cosmogenic nuclides

International Nuclear Information System (INIS)

Reedy, R.C.

1988-01-01

A wide variety of products from cosmic-ray interactions have been measured in terrestrial or extraterrestrial samples. These ''cosmogenic'' products include radiation damage tracks and rare nuclides that are made by nuclear reactions. They often have been used to determine the fluxes and composition of cosmic-ray particles in the past, but they are usually used to study the history of the ''target'' (such as the time period that it was exposed to cosmic-ray particles). Products made by both the high-energy galactic cosmic rays and energetic particles emitted irregularly from the Sun have been extensively studied. Some of these cosmogenic products, especially nuclides, have been or can be applied to studies of Antarctic meteorite stranding surfaces, the ice surfaces in Antarctica where meteorites have been found. Cosmogenic nuclides studied in samples from Antarctica and reported by others elsewhere in this volume include those in meteorites, especially radionuclides used to determine terrestrial ages, and those made in situ in terrestrial rocks. Cosmogenic nuclides made in the Earth's atmosphere or brought in with cosmic dust have also been studied in polar ice, and it should also be possible to measure nuclides made in situ in ice. As an introduction to cosmogenic nuclides and their applications, cosmic rays and their interactions will be presented below and production systematics of cosmogenic nuclides in these various media will be discussed later. 20 refs., 2 tabs

Cosmic-ray interactions and dating of meteorite stranding surfaces with cosmogenic nuclides

Energy Technology Data Exchange (ETDEWEB)

Reedy, R.C.

1988-01-01

A wide variety of products from cosmic-ray interactions have been measured in terrestrial or extraterrestrial samples. These ''cosmogenic'' products include radiation damage tracks and rare nuclides that are made by nuclear reactions. They often have been used to determine the fluxes and composition of cosmic-ray particles in the past, but they are usually used to study the history of the ''target'' (such as the time period that it was exposed to cosmic-ray particles). Products made by both the high-energy galactic cosmic rays and energetic particles emitted irregularly from the Sun have been extensively studied. Some of these cosmogenic products, especially nuclides, have been or can be applied to studies of Antarctic meteorite stranding surfaces, the ice surfaces in Antarctica where meteorites have been found. Cosmogenic nuclides studied in samples from Antarctica and reported by others elsewhere in this volume include those in meteorites, especially radionuclides used to determine terrestrial ages, and those made in situ in terrestrial rocks. Cosmogenic nuclides made in the Earth's atmosphere or brought in with cosmic dust have also been studied in polar ice, and it should also be possible to measure nuclides made in situ in ice. As an introduction to cosmogenic nuclides and their applications, cosmic rays and their interactions will be presented below and production systematics of cosmogenic nuclides in these various media will be discussed later. 20 refs., 2 tabs.

Atmospheric ions and pollution. Ions of the cosmic radiation

International Nuclear Information System (INIS)

Cachon, A.

1977-01-01

The principal historical steps before the so-called 'cosmic radiation' was known as an extra-terrestrial radiation are described. The origin, nature and energy of the radiation are discussed together with its evolution all along its path through atmosphere, in view of the interaction that occurs between the radiation and the atmosphere. The mechanism of the ionization induced by cosmic radiation is analyzed, the corresponding energy balance is established and the possible singularities in air ionization induced by cosmic rays are discussed [fr

[Extrasolar terrestrial planets and possibility of extraterrestrial life].

Science.gov (United States)

Ida, Shigeru

2003-12-01

Recent development of research on extrasolar planets are reviewed. About 120 extrasolar Jupiter-mass planets have been discovered through the observation of Doppler shift in the light of their host stars that is caused by acceleration due to planet orbital motions. Although the extrasolar planets so far observed may be limited to gas giant planets and their orbits differ from those of giant planets in our Solar system (Jupiter and Saturn), the theoretically predicted probability of existence of extrasolar terrestrial planets that can have liquid water ocean on their surface is comparable to that of detectable gas giant planets. Based on the number of extrasolar gas giants detected so far, about 100 life-sustainable planets may exist within a range of 200 light years. Indirect observation of extrasolar terrestrial planets would be done with space telescopes within several years and direct one may be done within 20 years. The latter can detect biomarkers on these planets as well.

The origin of life in a cosmic context

Science.gov (United States)

Sagan, C.

1974-01-01

It is shown that there is at present no aspect of contemporary biology where the contingent can be distinguished from the necessary, or the evolutionary accident from the biological sine qua non; and no amount of terrestrial experimentation alone is likely to make such distinctions possible. Hence, biology suffers from a deadening parochialism, much like the physics of falling bodies before Newton showed that the same laws applied to the motion of apples in England and to the planets about the sun. The deparochialization of biology can only come in the same way and must therefore await the search for extraterrestrial life. It is in this sense that the significance of explorations of the planets and their satellites, asteroids, comets, and the interplanetary medium for the origin of life is assessed.

Multi-spectra Cosmic Ray Flux Measurement

Science.gov (United States)

He, Xiaochun; Dayananda, Mathes

2010-02-01

The Earth's upper atmosphere is constantly bombarded by rain of charged particles known as primary cosmic rays. These primary cosmic rays will collide with the atmospheric molecules and create extensive secondary particles which shower downward to the surface of the Earth. In recent years, a few studies have been done regarding to the applications of the cosmic ray measurements and the correlations between the Earth's climate conditions and the cosmic ray fluxes [1,2,3]. Most of the particles, which reach to the surface of the Earth, are muons together with a small percentage of electrons, gammas, neutrons, etc. At Georgia State University, multiple cosmic ray particle detectors have been constructed to measure the fluxes and energy distributions of the secondary cosmic ray particles. In this presentation, we will briefly describe these prototype detectors and show the preliminary test results. Reference: [1] K.Borozdin, G.Hogan, C.Morris, W.Priedhorsky, A.Saunders, L.Shultz, M.Teasdale, Nature, Vol.422, 277 (2003). [2] L.V. Egorova, V. Ya Vovk, O.A. Troshichev, Journal of Atmospheric and Terrestrial Physics 62, 955-966 (2000). [3] Henrik Svensmark, Phy. Rev. Lett. 81, 5027 (1998). )

Alteration of Organic Compounds in Small Bodies and Cosmic Dusts by Cosmic Rays and Solar Radiation

Science.gov (United States)

Kobayashi, Kensei; Kaneko, Takeo; Mita, Hajime; Obayashi, Yumiko; Takahashi, Jun-ichi; Sarker, Palash K.; Kawamoto, Yukinori; Okabe, Takuto; Eto, Midori; Kanda, Kazuhiro

2012-07-01

A wide variety of complex organic compounds have been detected in extraterrestrial bodies like carbonaceous chondrites and comets, and their roles in the generation of terrestrial life are discussed. It was suggested that organics in small bodies were originally formed in ice mantles of interstellar dusts in dense cloud. Irradiation of frozen mixture of possible interstellar molecules including CO (or CH _{3}OH), NH _{3} and H _{2}O with high-energy particles gave complex amino acid precursors with high molecular weights [1]. Such complex organic molecules were taken in planetesimals or comets in the early solar system. In prior to the generation of the terrestrial life, extraterrestrial organics were delivered to the primitive Earth by such small bodies as meteorites, comets and space dusts. These organics would have been altered by cosmic rays and solar radiation (UV, X-rays) before the delivery to the Earth. We examined possible alteration of amino acids, their precursors and nucleic acid bases in interplanetary space by irradiation with high energy photons and heavy ions. A mixture of CO, NH _{3} and H _{2}O was irradiated with high-energy protons from a van de Graaff accelerator (TIT, Japan). The resulting products (hereafter referred to as CAW) are complex precursors of amino acids. CAW, amino acids (dl-Isovaline, glycine), hydantoins (amino acid precursors) and nucleic acid bases were irradiated with continuous emission (soft X-rays to IR; hereafter referred to as soft X-rays irradiation) from BL-6 of NewSUBARU synchrotron radiation facility (Univ. Hyogo). They were also irradiated with heavy ions (eg., 290 MeV/u C ^{6+}) from HIMAC accelerator (NIRS, Japan). After soft X-rays irradiation, water insoluble materials were formed. After irradiation with soft X-rays or heavy ions, amino acid precursors (CAW and hydantoins) gave higher ratio of amino acids were recovered after hydrolysis than free amino acids. Nucleic acid bases showed higher stability than free

Signatures of cosmic-ray interactions on the solar surface

Science.gov (United States)

Seckel, D.; Stanev, Todor; Gaisser, T. K.

1991-01-01

The fluxes of neutrinos, gamma rays, antiprotons, neutrons, and antineutrons that result from collisions of high-energy Galactic cosmic rays with the solar atmosphere are estimated. The results are sensitive to assumptions about cosmic-ray transport in the magnetic fields of the inner solar system. The high-energy photon flux should be observable by the Gamma Ray Observatory. The neutrino flux should produce less than one event per year in the next generation of neutrino telescopes. The antiproton flux is unobservable against the Galactic background. The neutron and antineutron fluxes are detectable only if neutrons produced in terrestrial cosmic-ray events may be discriminated against.

Do pioneers have r-selected traits? Life history patterns among colonizing terrestrial gastropods.

Science.gov (United States)

Bengtsson, J; Baur, B

1993-05-01

We examine whether pioneer species of terrestrial gastropods (snails and slugs) possess particular life history traits commonly associated with r-selection, using data on gastropod colonization in four areas in north-west Europe (the Kvarken and Tvärminne archipelagos in the Baltic, polder woods in IJsselmeer, and a rehabilitated quarry near Maastricht). Data on age at first reproduction, longevity, clutch size, egg size and lifetime fecundity were gathered from the literature. In order to control for potentially confounding effects of body size on life history traits, we compared the residuals from the allometric relations between life history traits and body size for pioneers and non-pioneers. In snails, all life history traits examined were related to body size. In slugs, all traits except age at first reproduction scaled with body size. Body sizes did not differ between pioneers and non-pioneers in any area. In all four areas, there were no significant differences between pioneers and non-pioneers in any of the life history traits examined, after body size had been taken into account. This indicates that pioneer terrestrial gastropods generally cannot be regarded as r-selected. Pioneer species may possess any of several life history strategies, and the combinations of traits shown by them may have little in common with the r-K selection concept.

The Cosmic Zoo: The (Near) Inevitability of the Evolution of Complex, Macroscopic Life

Science.gov (United States)

Bains, William; Schulze-Makuch, Dirk

2016-01-01

Life on Earth provides a unique biological record from single-cell microbes to technologically intelligent life forms. Our evolution is marked by several major steps or innovations along a path of increasing complexity from microbes to space-faring humans. Here we identify various major key innovations, and use an analytical toolset consisting of a set of models to analyse how likely each key innovation is to occur. Our conclusion is that once the origin of life is accomplished, most of the key innovations can occur rather readily. The conclusion for other worlds is that if the origin of life can occur rather easily, we should live in a cosmic zoo, as the innovations necessary to lead to complex life will occur with high probability given sufficient time and habitat. On the other hand, if the origin of life is rare, then we might live in a rather empty universe. PMID:27376334

Inconstant sun: how solar evolution has affected cosmic and ultraviolet radiation exposure over the history of life on Earth.

Science.gov (United States)

Karam, P Andrew

2003-03-01

Four billion years ago, sea-level UV exposure was more than 400 times as intense as today, the dose from solar cosmic rays was five times present levels, and galactic cosmic rays accounted for only about 10% their current contribution to sea-level radiation doses. Exposure to cosmic radiation accounts for about 10% of natural background radiation exposure today and includes dose from galactic cosmic rays and solar charged particles. There is little exposure to ionizing wavelengths of UV due to absorption by ozone. The sun has evolved significantly over its life; in the past there were higher levels of particulate radiation and lower UV emissions from the sun, and a stronger solar wind reduced radiation dose in the inner solar system from galactic cosmic rays. Finally, since the early atmosphere contained little to no oxygen, surface levels of UV radiation were far higher in the past.

Simulating Terrestrial Gamma Ray Flashes due to cosmic ray shower electrons and positrons

Science.gov (United States)

Connell, Paul

2017-04-01

The University of Valencia has developed a software simulator LEPTRACK to simulate the relativistic runaway electron avalanches, RREA, that are presumed to be the cause of Terrestrial Gamma Ray Flashes and their powerful accompanying Ionization/Excitation Flashes. We show here results of LEPTRACK simulations of RREA by the interaction of MeV energy electrons/positrons and photons in cosmic ray showers traversing plausible electric field geometries expected in storm clouds. The input beams of MeV shower products were created using the CORSIKA software package from the Karlsruhe Institute of Technology. We present images, videos and plots showing the different Ionization, Excitation and gamma-ray photon density fields produced, along with their time and spatial profile evolution, which depend critically on where the line of shower particles intercept the electric field geometry. We also show a new effect of incoming positrons in the shower, which make up a significant fraction of shower products, in particular their apparent "orbiting" within a high altitude negative induced shielding charge layer, which has been conjectured to produce a signature microwave emission, as well as a short range 511 keV annihilation line. The interesting question posed is if this conjectured positron emission can be observed and correlated with TGF orbital observations to show if a TGF originates in the macro E-fields of storm clouds or the micro E-fields of lightning leaders where this positron "orbiting" is not likely to occur.

The Cosmic Zoo: The (Near Inevitability of the Evolution of Complex, Macroscopic Life

Directory of Open Access Journals (Sweden)

William Bains

2016-06-01

Full Text Available Life on Earth provides a unique biological record from single-cell microbes to technologically intelligent life forms. Our evolution is marked by several major steps or innovations along a path of increasing complexity from microbes to space-faring humans. Here we identify various major key innovations, and use an analytical toolset consisting of a set of models to analyse how likely each key innovation is to occur. Our conclusion is that once the origin of life is accomplished, most of the key innovations can occur rather readily. The conclusion for other worlds is that if the origin of life can occur rather easily, we should live in a cosmic zoo, as the innovations necessary to lead to complex life will occur with high probability given sufficient time and habitat. On the other hand, if the origin of life is rare, then we might live in a rather empty universe.

In situ measurements of dose rates from terrestrial gamma rays

International Nuclear Information System (INIS)

Horng, M.C.; Jiang, S.H.

2002-01-01

A portable, high purity germanium (HPGe) detector was employed for the performance of in situ measurements of radionuclide activity concentrations in the ground in Taiwan, at altitudes ranging from sea level to 3900 m. The absolute peak efficiency of the HPGe detector for a gamma-ray source uniformly distributed in the semi-infinite ground was determined using a semi-empirical method. The gamma-ray dose rates from terrestrial radionuclides were calculated from the measured activity levels using recently published dose rate conversion factors. The absorbed dose rate in air due to cosmic rays was derived by subtracting the terrestrial gamma-ray dose rate from the overall absorbed dose rate in air measured using a high-pressure ionization chamber. The cosmic-ray dose rate calculated as a function of altitude, was found to be in good agreement with the data reported by UNSCEAR. (orig.)

Analytical Model for Estimating the Zenith Angle Dependence of Terrestrial Cosmic Ray Fluxes.

Directory of Open Access Journals (Sweden)

Tatsuhiko Sato

Full Text Available A new model called "PHITS-based Analytical Radiation Model in the Atmosphere (PARMA version 4.0" was developed to facilitate instantaneous estimation of not only omnidirectional but also angular differential energy spectra of cosmic ray fluxes anywhere in Earth's atmosphere at nearly any given time. It consists of its previous version, PARMA3.0, for calculating the omnidirectional fluxes and several mathematical functions proposed in this study for expressing their zenith-angle dependences. The numerical values of the parameters used in these functions were fitted to reproduce the results of the extensive air shower simulation performed by Particle and Heavy Ion Transport code System (PHITS. The angular distributions of ground-level muons at large zenith angles were specially determined by introducing an optional function developed on the basis of experimental data. The accuracy of PARMA4.0 was closely verified using multiple sets of experimental data obtained under various global conditions. This extension enlarges the model's applicability to more areas of research, including design of cosmic-ray detectors, muon radiography, soil moisture monitoring, and cosmic-ray shielding calculation. PARMA4.0 is available freely and is easy to use, as implemented in the open-access EXcel-based Program for Calculating Atmospheric Cosmic-ray Spectrum (EXPACS.

Biogeochemical signals from deep microbial life in terrestrial crust.

Directory of Open Access Journals (Sweden)

Yohey Suzuki

Full Text Available In contrast to the deep subseafloor biosphere, a volumetrically vast and stable habitat for microbial life in the terrestrial crust remains poorly explored. For the long-term sustainability of a crustal biome, high-energy fluxes derived from hydrothermal circulation and water radiolysis in uranium-enriched rocks are seemingly essential. However, the crustal habitability depending on a low supply of energy is unknown. We present multi-isotopic evidence of microbially mediated sulfate reduction in a granitic aquifer, a representative of the terrestrial crust habitat. Deep meteoric groundwater was collected from underground boreholes drilled into Cretaceous Toki granite (central Japan. A large sulfur isotopic fractionation of 20-60‰ diagnostic to microbial sulfate reduction is associated with the investigated groundwater containing sulfate below 0.2 mM. In contrast, a small carbon isotopic fractionation (<30‰ is not indicative of methanogenesis. Except for 2011, the concentrations of H2 ranged mostly from 1 to 5 nM, which is also consistent with an aquifer where a terminal electron accepting process is dominantly controlled by ongoing sulfate reduction. High isotopic ratios of mantle-derived 3He relative to radiogenic 4He in groundwater and the flux of H2 along adjacent faults suggest that, in addition to low concentrations of organic matter (<70 µM, H2 from deeper sources might partly fuel metabolic activities. Our results demonstrate that the deep biosphere in the terrestrial crust is metabolically active and playing a crucial role in the formation of reducing groundwater even under low-energy fluxes.

Measurement of cosmic-ray muons with the Distributed Electronic Cosmic-ray Observatory, a network of smartphones

International Nuclear Information System (INIS)

Vandenbroucke, J.; Bravo, S.; Karn, P.; Meehan, M.; Plewa, M.; Schultz, D.; Tosi, D.; BenZvi, S.; Jensen, K.; Peacock, J.; Ruggles, T.; Santander, M.; Simons, A.L.

2016-01-01

Solid-state camera image sensors can be used to detect ionizing radiation in addition to optical photons. We describe the Distributed Electronic Cosmic-ray Observatory (DECO), an app and associated public database that enables a network of consumer devices to detect cosmic rays and other ionizing radiation. In addition to terrestrial background radiation, cosmic-ray muon candidate events are detected as long, straight tracks passing through multiple pixels. The distribution of track lengths can be related to the thickness of the active (depleted) region of the camera image sensor through the known angular distribution of muons at sea level. We use a sample of candidate muon events detected by DECO to measure the thickness of the depletion region of the camera image sensor in a particular consumer smartphone model, the HTC Wildfire S. The track length distribution is fit better by a cosmic-ray muon angular distribution than an isotropic distribution, demonstrating that DECO can detect and identify cosmic-ray muons despite a background of other particle detections. Using the cosmic-ray distribution, we measure the depletion thickness to be 26.3 ± 1.4 μm. With additional data, the same method can be applied to additional models of image sensor. Once measured, the thickness can be used to convert track length to incident polar angle on a per-event basis. Combined with a determination of the incident azimuthal angle directly from the track orientation in the sensor plane, this enables direction reconstruction of individual cosmic-ray events using a single consumer device. The results simultaneously validate the use of cell phone camera image sensors as cosmic-ray muon detectors and provide a measurement of a parameter of camera image sensor performance which is not otherwise publicly available

The role of cosmic rays in the atmospheric processes

Energy Technology Data Exchange (ETDEWEB)

Stozhkov, Y I [Lebedev Physical Institute, Russian Academy of Sciences, 119991, Leninsky Prospect, 53, Moscow (Russian Federation)

2003-05-01

The energy flux of galactic cosmic rays falling on the earth's atmosphere is small in comparison with solar electromagnetic irradiation (by 10{sup 8} times). But at altitudes of h {approx} 3 to 35 km in the atmosphere, cosmic rays are the only ionization source (from the ground level up to h {approx} 3 km, natural radioactivity is an additional source of ionization). Solar activity modulates cosmic ray flux. The cosmic rays produce atmospheric ions that define the electrical properties of the atmosphere. The electric charges play a very important role in the processes of cloud and thundercloud formation in the operation of the global electric circuit. The changes in electric properties of the atmosphere influence weather and climate. Thus, we have the following chain of the solar terrestrial relationship: solar activity - cosmic ray modulation - changes in the global electric properties of the atmosphere - changes in weather and climate. The following questions are discussed in this paper: light ion production in the atmosphere, role of electric charges in the formation of clouds and thunderclouds, experimental evidences of the relationships between cosmic ray flux and atmospheric current and lightning.

The role of cosmic rays in the atmospheric processes

International Nuclear Information System (INIS)

Stozhkov, Y I

2003-01-01

The energy flux of galactic cosmic rays falling on the earth's atmosphere is small in comparison with solar electromagnetic irradiation (by 10 8 times). But at altitudes of h ∼ 3 to 35 km in the atmosphere, cosmic rays are the only ionization source (from the ground level up to h ∼ 3 km, natural radioactivity is an additional source of ionization). Solar activity modulates cosmic ray flux. The cosmic rays produce atmospheric ions that define the electrical properties of the atmosphere. The electric charges play a very important role in the processes of cloud and thundercloud formation in the operation of the global electric circuit. The changes in electric properties of the atmosphere influence weather and climate. Thus, we have the following chain of the solar terrestrial relationship: solar activity - cosmic ray modulation - changes in the global electric properties of the atmosphere - changes in weather and climate. The following questions are discussed in this paper: light ion production in the atmosphere, role of electric charges in the formation of clouds and thunderclouds, experimental evidences of the relationships between cosmic ray flux and atmospheric current and lightning

MARS A Cosmic Stepping Stone Uncovering Humanity’s Cosmic Context

CERN Document Server

Nolan, Kevin

2008-01-01

The questions of our origin and cosmic abundance of life are among the most compelling facing humanity. We have determined much about the nature and origin of the Universe and our place in it, but with virtually all evidence of our origin long since gone from our world and an unimaginably vast Universe still to explore, defining answers are difficult to obtain. For all of the difficulties facing us however, the planet Mars may act as a ‘cosmic stepping stone’ in uncovering some of the answers. Although different today, the origin and early history of both Earth and Mars may have been similar enough to consider an origin to life on both. But because Mars’ planetary processes collapsed over three billion years ago – just as life was beginning to flourish on Earth – a significant and unique record of activity from that era perhaps relevant to the origin of life still resides there today. In recognition of this, both the US and Europe are currently engaged in one of the most ambitious programs of explor...

Spatial and temporal variability across life's hierarchies in the terrestrial Antarctic.

Science.gov (United States)

Chown, Steven L; Convey, Peter

2007-12-29

Antarctica and its surrounding islands lie at one extreme of global variation in diversity. Typically, these regions are characterized as being species poor and having simple food webs. Here, we show that terrestrial systems in the region are nonetheless characterized by substantial spatial and temporal variations at virtually all of the levels of the genealogical and ecological hierarchies which have been thoroughly investigated. Spatial variation at the individual and population levels has been documented in a variety of genetic studies, and in mosses it appears that UV-B radiation might be responsible for within-clump mutagenesis. At the species level, modern molecular methods have revealed considerable endemism of the Antarctic biota, questioning ideas that small organisms are likely to be ubiquitous and the taxa to which they belong species poor. At the biogeographic level, much of the relatively small ice-free area of Antarctica remains unsurveyed making analyses difficult. Nonetheless, it is clear that a major biogeographic discontinuity separates the Antarctic Peninsula and continental Antarctica, here named the 'Gressitt Line'. Across the Southern Ocean islands, patterns are clearer, and energy availability is an important correlate of indigenous and exotic species richness, while human visitor numbers explain much of the variation in the latter too. Temporal variation at the individual level has much to do with phenotypic plasticity, and considerable life-history and physiological plasticity seems to be a characteristic of Antarctic terrestrial species. Environmental unpredictability is an important driver of this trait and has significantly influenced life histories across the region and probably throughout much of the temperate Southern Hemisphere. Rapid climate change-related alterations in the range and abundance of several Antarctic and sub-Antarctic populations have taken place over the past several decades. In many sub-Antarctic locations, these

Data processing in cosmic rays at the Institute of Physical and Chemical Research

International Nuclear Information System (INIS)

Wada, Masami

1980-01-01

Data processing performed by the World Data Center for Cosmic Rays, installed at the Institute of Physical and Chemical Research (IPCR) is reported. The Center was set up as a member of the World Data Center for Solar and Terrestrial Physics and performs assigned services. There are several C-level World Data Centers in Japan, and the DC for Cosmic Rays, IPCR, is described in detail, in the context of cosmic ray research itself. As to the future of the Center, IPCR, personal opinions and expectations are made. Thus a glimpse on a century of International Cooperative Observation and a quarter century of world data center operations are made from cosmic ray research side. (author)

Terrestrial and exposure histories of Antarctic meteorites

International Nuclear Information System (INIS)

Nishiizumi, K.

1986-01-01

Records of cosmogenic effects were studied in a large suite of Antarctic meteorites. The cosmogenic nuclide measurements together with cosmic ray track measurements on Antartic meteorites provide information such as exposure age, terrestrial age, size and depth in meteoroid or parent body, influx rate in the past, and pairing. The terrestrail age is the time period between the fall of the meteorite on the Earth and the present. To define terrestrial age, two or more nuclides with different half-lives and possibly noble gases are required. The cosmogenic radionuclides used are C-14, Kr-81, Cl-36, Al-26, Be-10, Mn-53, and K-40

Terrestrial and exposure histories of Antarctic meteorites

Science.gov (United States)

Nishiizumi, K.

1986-01-01

Records of cosmogenic effects were studied in a large suite of Antarctic meteorites. The cosmogenic nuclide measurements together with cosmic ray track measurements on Antartic meteorites provide information such as exposure age, terrestrial age, size and depth in meteoroid or parent body, influx rate in the past, and pairing. The terrestrail age is the time period between the fall of the meteorite on the Earth and the present. To define terrestrial age, two or more nuclides with different half-lives and possibly noble gases are required. The cosmogenic radionuclides used are C-14, Kr-81, Cl-36, Al-26, Be-10, Mn-53, and K-40.

Multitaper spectral analysis of cosmic rays Sao Martinho da Serra's muon telescope and Newark's neutron monitor data

Energy Technology Data Exchange (ETDEWEB)

Silva, Marlos Rockenbach da; Alarcon, Walter Demetrio Gonzalez; Echer, Ezequiel; Lago, Alisson dal; Lucas, Aline de [National Institute for Space Research - INPE-MCT, Sao Jose dos Campos, SP (Brazil); Vieira, Luis Eduardo Antunes; Guarnieri, Fernando Luis [Universidade do Vale do Paraiba - UNIVAP, Sao Jose dos Campos, SP (Brazil); Schuch, Nelson Jorge [Southern Regional Space Research Center - CRSPE/INPE-MCT, Santa Maria, RS (Brazil); Munakata, Kazuoki, E-mail: marlos@dge.inpe.br, E-mail: gonzalez@dge.inpe.br, E-mail: eecher@dge.inpe.br, E-mail: dallago@dge.inpe.br, E-mail: delucas@dge.inpe.br, E-mail: levieira@univap.br, E-mail: guarnieri@univap.br, E-mail: njschuch@lacesm.ufsm.br, E-mail: kmuna00@gipac.shinshu-u.ac.jp [Physics Department, Shinshu University, Matsumoto (Japan)

2007-07-01

In this work we present an analysis on the correction efficiency of atmospheric effects on cosmic ray Sao Martinho da Serra's muon telescope and Newark's neutron monitor data. We use a Multitaper spectral analysis of cosmic rays time series to show the main periodicities present in the corrected and uncorrected data for the atmospheric effects. This kind of correction is very important when intends to study cosmic rays variations of extra-terrestrial origin. (author)

Radiative hazard of solar flares in the nearterrestrial cosmic space

International Nuclear Information System (INIS)

Kolomenskij, A.V.; Petrov, V.M.; Zil', M.V.; Eremkina, T.M.

1978-01-01

Simulation of radiation enviroment due to solar cosmic rays was carried out in the near-terrestrial space. Systematized are the data on cosmic ray flux and spectra detected during 19-th and 20-th cycles of solar activity. 127 flares are considered with proton fluxes of more than 10 proton/cm 2 at energies higher than 30 MeV. Obtained are distribution functions of intervals between flares, flux distribution of flares and characteristic rigidity, and also distribution of magnetic disturbances over Dsub(st)-variation amplitude. The totality of these distributions presents the statistic model of radiation enviroment caused by solar flare protons for the period of maximum solar .activity. This model is intended for estimation of radiation hazard at manned cosmic flights

Testing Cosmic Inflation

Science.gov (United States)

Chuss, David

2010-01-01

The Cosmic Microwave Background (CMB) has provided a wealth of information about the history and physics of the early Universe. Much progress has been made on uncovering the emerging Standard Model of Cosmology by such experiments as COBE and WMAP, and ESA's Planck Surveyor will likely increase our knowledge even more. Despite the success of this model, mysteries remain. Currently understood physics does not offer a compelling explanation for the homogeneity, flatness, and the origin of structure in the Universe. Cosmic Inflation, a brief epoch of exponential expansion, has been posted to explain these observations. If inflation is a reality, it is expected to produce a background spectrum of gravitational waves that will leave a small polarized imprint on the CMB. Discovery of this signal would give the first direct evidence for inflation and provide a window into physics at scales beyond those accessible to terrestrial particle accelerators. I will briefly review aspects of the Standard Model of Cosmology and discuss our current efforts to design and deploy experiments to measure the polarization of the CMB with the precision required to test inflation.

Galactic cosmic ray-induced radiation dose on terrestrial exoplanets.

Science.gov (United States)

Atri, Dimitra; Hariharan, B; Grießmeier, Jean-Mathias

2013-10-01

This past decade has seen tremendous advancements in the study of extrasolar planets. Observations are now made with increasing sophistication from both ground- and space-based instruments, and exoplanets are characterized with increasing precision. There is a class of particularly interesting exoplanets that reside in the habitable zone, which is defined as the area around a star where the planet is capable of supporting liquid water on its surface. Planetary systems around M dwarfs are considered to be prime candidates to search for life beyond the Solar System. Such planets are likely to be tidally locked and have close-in habitable zones. Theoretical calculations also suggest that close-in exoplanets are more likely to have weaker planetary magnetic fields, especially in the case of super-Earths. Such exoplanets are subjected to a high flux of galactic cosmic rays (GCRs) due to their weak magnetic moments. GCRs are energetic particles of astrophysical origin that strike the planetary atmosphere and produce secondary particles, including muons, which are highly penetrating. Some of these particles reach the planetary surface and contribute to the radiation dose. Along with the magnetic field, another factor governing the radiation dose is the depth of the planetary atmosphere. The higher the depth of the planetary atmosphere, the lower the flux of secondary particles will be on the surface. If the secondary particles are energetic enough, and their flux is sufficiently high, the radiation from muons can also impact the subsurface regions, such as in the case of Mars. If the radiation dose is too high, the chances of sustaining a long-term biosphere on the planet are very low. We have examined the dependence of the GCR-induced radiation dose on the strength of the planetary magnetic field and its atmospheric depth, and found that the latter is the decisive factor for the protection of a planetary biosphere.

Planetary Habitability over Cosmic-Time Based on Cosmic-Ray Levels

Science.gov (United States)

Mason, Paul A.; Biermann, Peter L.

2016-01-01

Extreme cosmic-ray (CR) fluxes have a negative effect on life when flux densities are high enough to cause excessive biological, especially DNA, damage. The CR history of a planet plays an important role in its potential surface habitation. Both global and local CR conditions determine the ability of life to survive for astrobiologically relevant time periods. We highlight two CR life-limiting factors: 1) General galactic activity, starburst and AGN, was up by about a factor of 30 at redshift 1 - 2, per comoving frame, averaged over all galaxies. And 2) AGN activity is highly intermittent, so extreme brief but powerful bursts (Her A for example) can be detrimental at great distances. This means that during such brief bursts of AGN activity the extragalactic CRs might even overpower the local galactic CRs. But as shown by the starburst galaxy M82, the local CRs in a starburst can also be quite high. Moreover, in our cosmic neighborhood we have several super-massive black holes. These are in M31, M32, M81, NGC5128 (Cen A), and in our own Galaxy, all within about 4 Mpc today. Within about 20 Mpc today there are many more super-massive black holes. Cen A is of course the most famous one now, since it may be a major source of the ultra-high-energy CRs (UHECRs). Folding in what redshift means in terms of cosmic time, this implies that there may have been little chance for life to survive much earlier than Earth's starting epoch. We speculate, on whether the very slow start oflife on Earth is connected to the decay of disturbing CR activity.

Contribution to the study of the accretion of cosmic dust on earth

International Nuclear Information System (INIS)

Grjebine, Tovy

1971-01-01

The study of the accretion of cosmic dust has been carried out by different ways and techniques. The measurements of the presently falling cosmic dust must be limited to that stratospheric contribution which has spent only a short time in the stratosphere, otherwise it can be mixed with a possible terrestrial dust of very small size. The discrimination between those different components can be made by studying the geographical and time distribution, correlated or anti-correlated with other phenomena such as radio-meteor statistics, meteorological phenomena statistics (rain or nuclear bomb debris fallout). It is impossible to measure directly the weight of the falling dust but the weight must be deduced from the measurements of some other characteristics such as magnetism, which are not characteristic of terrestrial dust. The 'magnetism ratio/weight' or 'chemical iron/weight' has therefore been established for stratospheric collection, and then used for soil level collection. The collection of spherules is another approach to measure the accretion in the size range of some micron particles. Spherules are considered as cosmic for their non-terrestrial type average chemical composition, non terrestrial association of elements and presence of cosmogenic nuclei. The knowledge of their average chemical composition enables their utilisation as a geochemical model to calculate the total weight of matter which should be associated with the content of nickel and cobalt found in the deep sea bottoms. Depending on the collection method, the total mass accreted yearly by the earth is estimated around 10 4 if only microscopic spherules are considered, around 10 8 if all size collection is performed or if deep sea sediments nickel and cobalt are used with spherules as a geochemical model. (author) [fr

A journey with Fred Hoyle. The search for cosmic life

Science.gov (United States)

Wickramasinghe, Chandra; Wickramasinghe, Kamala

2005-01-01

This is the story of the author's unique scientific journey with one of the most remarkable men of 20th century science. The journey begins in Sri Lanka, the author's native country, with his childhood acquaintance with Fred Hoyle's writings. The action then moves to Cambridge, where the famous Hoyle-Wickramasinghe collaborations begin. A research programme which was started in 1962 on the carbonaceous nature of interstellar dust leads, over the next two decades, to developments that are continued in both Cambridge and Cardiff. These developments prompt Hoyle and the author to postulate the organic theory of cosmic dust (which is now generally accepted), and then to challenge one of the most cherished paradigms of contemporary science - the theory that life originated on Earth in a warm primordial soup.

Is there a link between cancer and cosmic rays?

International Nuclear Information System (INIS)

Astbury, A.

2000-06-01

Conventional wisdom on the carcinogenic effects of ionizing radiation predicts that only a very small percentage of human deaths from cancer can be attributed to cosmic rays. The intensity of the hadronic component of terrestrial cosmic rays, in particular neutrons, is well measured as a function of vertical threshold rigidity (M, in GeV/c). The crude death rates from malignant neoplasms for countries of the world and states of the US reveal a correlation with M. A close examination of eight US states with M ≤ 1.5 GeV/c over the period 1947-1997 shows systematic time variations with periodicities reminiscent of sunspot cycles (∼11 years). A very simple model linking the death rate from cancer to the count rate in a cosmic ray neutron monitor reproduces the gross features of the data. The evidence suggests that conventional wisdom could well be challenged. The situation may only be resolved by a series of detailed measurements of the genetic impact of hadronic cosmic rays on cells. (author)

Extrapolating cosmic ray variations and impacts on life: Morlet wavelet analysis

Science.gov (United States)

Zarrouk, N.; Bennaceur, R.

2009-07-01

Exposure to cosmic rays may have both a direct and indirect effect on Earth's organisms. The radiation may lead to higher rates of genetic mutations in organisms, or interfere with their ability to repair DNA damage, potentially leading to diseases such as cancer. Increased cloud cover, which may cool the planet by blocking out more of the Sun's rays, is also associated with cosmic rays. They also interact with molecules in the atmosphere to create nitrogen oxide, a gas that eats away at our planet's ozone layer, which protects us from the Sun's harmful ultraviolet rays. On the ground, humans are protected from cosmic particles by the planet's atmosphere. In this paper we give estimated results of wavelet analysis from solar modulation and cosmic ray data incorporated in time-dependent cosmic ray variation. Since solar activity can be described as a non-linear chaotic dynamic system, methods such as neural networks and wavelet methods should be very suitable analytical tools. Thus we have computed our results using Morlet wavelets. Many have used wavelet techniques for studying solar activity. Here we have analysed and reconstructed cosmic ray variation, and we have better depicted periods or harmonics other than the 11-year solar modulation cycles.

Radio-wave detection of ultra-high-energy neutrinos and cosmic rays

Science.gov (United States)

Huege, Tim; Besson, Dave

2017-12-01

Radio waves, perhaps because our terrestrial atmosphere and the cosmos beyond are uniquely transparent to them, or perhaps because they are macroscopic, so the basic instruments of detection (antennas) are easily constructible, arguably occupy a privileged position within the electromagnetic spectrum, and, correspondingly, receive disproportionate attention experimentally. Detection of radio-frequency radiation, at macroscopic wavelengths, has blossomed within the last decade as a competitive method for the measurement of cosmic particles, particularly charged cosmic rays and neutrinos. Cosmic-ray detection via radio emission from extensive air showers has been demonstrated to be a reliable technique that has reached a reconstruction quality of the cosmic-ray parameters competitive with more traditional approaches. Radio detection of neutrinos in dense media seems to be the most promising technique to achieve the gigantic detection volumes required to measure neutrinos at energies beyond the PeV-scale flux established by IceCube. In this article, we review radio detection both of cosmic rays in the atmosphere, as well as neutrinos in dense media.

Heliospheric Modulation of Galactic Cosmic Rays; Diurnal Variability Abstract Details

Science.gov (United States)

Kalu, D. F.; Okpala, K. C.

2017-12-01

We have studied the variability of Cosmic rays flux during solar quiet days at mid and high latitudes in the Northern Hemisphere. By using the five (5) quietest days for each month and the five disturbed days for each month, the monthly mean diurnal variation of cosmic ray anisotropy have been derived for the period 1999-2015, which covers part of cycles 23, and cycle 24. This study seeks to understand the heliospheric contribution to the variation of these Cosmic rays on quietest days, three stations (Inuvik, Moscow, Rome) Neutron Monitors were employed. This study seeks to understand the important features of the high latitude and mid latitude diurnal wave, and how solar and geomagnetic activity may be influencing the wave characteristics. Cosmic ray wave characteristics were obtained by discrete Fourier transform (DFT). The mean, diurnal amplitude, phase and dispersion for each month's diurnal wave were calculated and profiled. There was clear indication that the terrestrial effect on the variability of the monthly mean was more associated with geomagnetic activity rather than rigidity of the cosmic rays. Correlation of the time series of these wave characteristic with solar and geomagnetic activity index showed better association with solar activity.

Correlation between ionospheric potential and the intensity of cosmic rays

International Nuclear Information System (INIS)

Meyerott, R.E.; Reagan, J.B.; Evans, J.E.

1983-01-01

Ionospheric potential variations with a period of about 10 yr have been observed in the data that have been acquired to date. Previous studies have shown that these variations appear to be correlated inversely with sunspot number and with solar wind velocity, and directly with cosmic ray intensity. Since the cosmic ray intensity is inversely correlated with sunspot number and solar wind velocity, these correlations all suggest that the long period variations are of solar origin. In this report it is shown that, over the limited period for which ionospheric potential measurements exist, the long period variations are better correlated with the aerosol burden injected into the stratosphere by large volcanic eruptions than with the intensity of cosmic rays. This result indicates that the long period variations in ionospheric potential are of terrestrial rather than solar origin. 20 references

Cosmic disposal of radioactive waste

Energy Technology Data Exchange (ETDEWEB)

Inoue, Y; Morisawa, S [Kyoto Univ. (Japan). Faculty of Engineering

1975-03-01

The technical and economical possibility and safety of the disposal of highly radioactive waste into cosmos are reviewed. The disposal of highly radioactive waste is serious problem to be solved in the near future, because it is produced in large amounts by the reprocessing of spent fuel. The promising methods proposed are (i) underground disposal, (ii) ocean disposal, (iii) cosmic disposal and (iv) extinguishing disposal. The final disposal method is not yet decided internationally. The radioactive waste contains very long life nuclides, for example transuranic elements and actinide elements. The author thinks the most perfect and safe disposal method for these very long life nuclides is the disposal into cosmos. The space vehicle carrying radioactive waste will be launched safely into outer space with recent space technology. The selection of orbit for vehicles (earth satellite or orbit around planets) or escape from solar system, selection of launching rocket type pretreatment of waste, launching weight, and the cost of cosmic disposal were investigated roughly and quantitatively. Safety problem of cosmic disposal should be examined from the reliable safety study data in the future.

The Universe: a Cryogenic Habitat for Microbial Life

Science.gov (United States)

Wickramasinghe, Chandra

Panspermia, an ancient idea, posits that microbial life is ubiquitous in the Universe. After several decades of almost irrational rejection, panspermia is at last coming to be regarded as a serious contender for the beginnings of life on our planet. Astronomical data is shown to be consistent with the widespread distribution of complex organic molecules and dust particles that may have a biological provenance. A minuscule (10-21) survival rate of freeze-dried bacteria in space is all that is needed to ensure the continual recycling of cosmic microbial life in the galaxy. Evidence that terrestrial life may have come from elsewhere in the solar system has accumulated over the past decade. Mars is seen by some as a possible source of terrestrial life, but some hundreds of billions of comets that enveloped the entire solar system, are a far more likely primordial reservoir of life. Comets would then have seeded Earth, Mars, and indeed all other habitable planetary bodies in the inner regions of the solar system. The implications of this point of view, which was developed in conjunction with the late Sir Fred Hoyle since the 1970's, are now becoming amenable to direct empirical test by studies of pristine organic material in the stratosphere. The ancient theory of panspermia may be on the verge of vindication, in which case the entire universe would be a grand crucible of cryomicrobiology.

Ultra-High Energy Cosmic Rays (2/3)

CERN Multimedia

CERN. Geneva

2012-01-01

The origin of the highest energy cosmic rays (UHECR) with energies above 1000 TeV, is still unknown. The discovery of their sources will reveal the engines of the most energetic astrophysical accelerators in the universe. In these lectures we present the recent observational results from HiRes, Telescope Array and Pierre Auger Observatory as well as (some of) the possible astrophysical origins of UHECR. These experiments deal with particle interactions at energies orders of magnitude higher than achieved in terrestrial accelerators.

Ultra-High Energy Cosmic Rays (1/3)

CERN Multimedia

CERN. Geneva

2012-01-01

The origin of the highest energy cosmic rays (UHECR) with energies above 1000 TeV, is still unknown. The discovery of their sources will reveal the engines of the most energetic astrophysical accelerators in the universe. In these lectures we present the recent observational results from HiRes, Telescope Array and Pierre Auger Observatory as well as (some of) the possible astrophysical origins of UHECR. These experiments deal with particle interactions at energies orders of magnitude higher than achieved in terrestrial accelerators.

Ultra-High Energy Cosmic Rays (3/3)

CERN Multimedia

CERN. Geneva

2012-01-01

The origin of the highest energy cosmic rays (UHECR) with energies above 1000 TeV, is still unknown. The discovery of their sources will reveal the engines of the most energetic astrophysical accelerators in the universe. In these lectures we present the recent observational results from HiRes, Telescope Array and Pierre Auger Observatory as well as (some of) the possible astrophysical origins of UHECR. These experiments deal with particle interactions at energies orders of magnitude higher than achieved in terrestrial accelerators.

Towards a Unified Source-Propagation Model of Cosmic Rays

Science.gov (United States)

Taylor, M.; Molla, M.

2010-07-01

report that the entire spectrum, spanning cosmic rays of local solar origin and those eminating from galactic and extra-galactic sources can be explained using a new diagnostic — the gradient of the log-log plot. This diagnostic reveals the known Boltmann statistics in the solar-terrestrial neighbourhood but at the highest energies — presumably at the cosmic ray source, with clearly separated fractal scales in between. We interpret this as modulation at the source followed by Fermi acceleration facilitated by galactic and extra-galactic magnetic fields with a final modulation in the solar-terrestrial neighbourhood. We conclude that the gradient of multifractal curves appears to be an excellent detector of fractality.

Characterizing Terrestrial Exoplanets

Science.gov (United States)

Meadows, V. S.; Lustig-Yaeger, J.; Lincowski, A.; Arney, G. N.; Robinson, T. D.; Schwieterman, E. W.; Deming, L. D.; Tovar, G.

2017-11-01

We will provide an overview of the measurements, techniques, and upcoming missions required to characterize terrestrial planet environments and evolution, and search for signs of habitability and life.

DNDO Report: Predicting Solar Modulation Potentials for Modeling Cosmic Background Radiation

Energy Technology Data Exchange (ETDEWEB)

Behne, Patrick Alan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-08-08

The modeling of the detectability of special nuclear material (SNM) at ports and border crossings requires accurate knowledge of the background radiation at those locations. Background radiation originates from two main sources, cosmic and terrestrial. Cosmic background is produced by high-energy galactic cosmic rays (GCR) entering the atmosphere and inducing a cascade of particles that eventually impact the earth’s surface. The solar modulation potential represents one of the primary inputs to modeling cosmic background radiation. Usosokin et al. formally define solar modulation potential as “the mean energy loss [per unit charge] of a cosmic ray particle inside the heliosphere…” Modulation potential, a function of elevation, location, and time, shares an inverse relationship with cosmic background radiation. As a result, radiation detector thresholds require adjustment to account for differing background levels, caused partly by differing solar modulations. Failure to do so can result in higher rates of false positives and failed detection of SNM for low and high levels of solar modulation potential, respectively. This study focuses on solar modulation’s time dependence, and seeks the best method to predict modulation for future dates using Python. To address the task of predicting future solar modulation, we utilize both non-linear least squares sinusoidal curve fitting and cubic spline interpolation. This material will be published in transactions of the ANS winter meeting of November, 2016.

A theory of ionospheric dynamo for complete model of terrestrial space at high and medium latitudes

International Nuclear Information System (INIS)

Vardanyan, Yu.S.

1992-01-01

A multi-layer model of terrestrial cosmic space at high and medium latitudes is considered in the approximation of infinite conductivity of the Earth taking into account the ambipolar diffusion processes in upper layers of ionosphere. 14 refs

From the solar system fo hidden cosmic structures

Energy Technology Data Exchange (ETDEWEB)

Benes, K

1987-01-01

The development of experimental astrophysics showed that in the evolution of planets, natural processes of a common nature take place. They include, e.g., radiogenic heat, the production of magmas, volcanic activity, degassing, etc. The solar system is a cosmic formation in an advanced stage of development and it is a realistic assumption that in the Galaxy other hidden planetary systems in various stages of development exist. The views on the possibility of the origination of life in other systems differ; life, however, is seen as a hidden property of cosmic matter. (M.D.).

Natural and man-made terrestrial electromagnetic noise: an outlook

Directory of Open Access Journals (Sweden)

A. Meloni

2007-06-01

Full Text Available The terrestrial environment is continuously exposed to electromagnetic radiations which set up a «background» electromagnetic noise. Within the Non Ionizing Radiation band (NIR, i.e. for frequencies lower than 300 GHz, this background can have a natural or an artificial origin. Natural origins of electromagnetic radiations are generally atmospheric or cosmic while artificial origins are technological applications, power transmission, communications, etc. This paper briefly describes the natural and man-made electromagnetic noise in the NIR band. Natural noise comes from a large variety of sources involving different physical phenomena and covering a wide range of frequencies and showing various propagation characteristics with an extremely broad range of power levels. Due to technological growth man-made electromagnetic noise is nowadays superimposed on natural noise almost everywhere on Earth. In the last decades man-made noise has increased dramatically over and above the natural noise in residential and business areas. This increase has led some scientists to consider possible negative effects of electromagnetic waves on human life and living systems in general. Accurate measurements of natural and man-made electromagnetic noise are necessary to understand the relative power levels in the different bands and their influence on life.

Muon Production in Relativistic Cosmic-Ray Interactions

International Nuclear Information System (INIS)

Klein, Spencer

2009-01-01

Cosmic-rays with energies up to 3 x 10 20 eV have been observed. The nuclear composition of these cosmic rays is unknown but if the incident nuclei are protons then the corresponding center of mass energy is √s nn = 700 TeV. High energy muons can be used to probe the composition of these incident nuclei. The energy spectra of high-energy (> 1 TeV) cosmic ray induced muons have been measured with deep underground or under-ice detectors. These muons come from pion and kaon decays and from charm production in the atmosphere. Terrestrial experiments are most sensitive to far-forward muons so the production rates aresensitive to high-x partons in the incident nucleus and low-x partons in the nitrogen/oxygen targets. Muon measurements can complement the central-particle data collected at colliders. This paper will review muon production data and discuss some non-perturbative (soft) models that have been used to interpret the data. I will show measurements of TeV muon transverse momentum (p T ) spectra in cosmic-ray air showers from MACRO, and describe how the IceCube neutrino observatory and the proposed Km3Net detector will extend these measurements to a higher p T region where perturbative QCD should apply. With a 1 km 2 surface area, the full IceCube detector should observe hundreds of muons/year with p T in the pQCD regime.

Muon Production in Relativistic Cosmic-Ray Interactions

International Nuclear Information System (INIS)

Klein, Spencer R.

2009-01-01

Cosmic-rays with energies up to 3x10 20 eV have been observed. The nuclear composition of these cosmic rays is unknown but if the incident nuclei are protons then the corresponding center of mass energy is √(s nn )=700TeV. High energy muons can be used to probe the composition of these incident nuclei. The energy spectra of high-energy (>1TeV) cosmic ray induced muons have been measured with deep underground or under-ice detectors. These muons come from pion and kaon decays and from charm production in the atmosphere. Terrestrial experiments are most sensitive to far-forward muons so the production rates are sensitive to high-x partons in the incident nucleus and low-x partons in the nitrogen/oxygen targets. Muon measurements can complement the central-particle data collected at colliders. This paper will review muon production data and discuss some non-perturbative (soft) models that have been used to interpret the data. I will show measurements of TeV muon transverse momentum (p T ) spectra in cosmic-ray air showers from MACRO, and describe how the IceCube neutrino observatory and the proposed Km3Net detector will extend these measurements to a higher p T region where perturbative QCD should apply. With a 1 km 2 surface area, the full IceCube detector should observe hundreds of muons/year with p T in the pQCD regime.

Cosmic rays in space

International Nuclear Information System (INIS)

Fujitaka, Kazunobu

2005-01-01

Cosmos is a mysterious space by which many researchers are fascinated for many years. But, going into space means that we will receive extra exposure due to existence of cosmic rays. Cosmic rays are mainly composed of highly energetic protons. It was born in the last stage of stellar life. Understanding of cosmos will certainly bring right understanding of radiation energy, or energy itself. As no one could see the very early stage of cosmic rays, there is only a speculation. But it is better to speculate something based on certain side evidences, than to give up the whole. Such attitude shall be welcomed in the space researches. Anyway, cosmic rays were born in the last explosion of a star, which is called as Super Nova. After cosmic rays are emitted from the Super Nova, it will reach to the human surroundings. To indicate its intensity, special unit of ''dose rate'' is used. When a man climbs a mountain, cosmic ray intensity surely increases. It doubles as he goes up every 1500m elevation. It was ascertained by our own measurements. Then what happens when the goes up more? At aviation altitude, where airplanes fly, the dose rate will be increased up to 100times the high mountain cases. And what is expected when he goes up further more, up to space orbit altitude? In this case, the dose rate increases up to 10times the airplane cases. Geomagnetism affects the dose rate very much. As primary cosmic ray particles are charged particles, they cannot do well with existence of the magnetic field. In effect, cosmic rays can penetrate into the polar atmosphere along geomagnetic lines of forces which stand almost vertical, but penetration of low energy cosmic rays will be banned when they intend to penetrate crossing the geomagnetic lines of forces in equatorial region. Therefore, exposure due to cosmic rays will become large in polar region, while it remains small in equatorial region. In effect, airplanes which fly over the equator. Only, we have to know that the cosmos

On scaling cosmogenic nuclide production rates for altitude and latitude using cosmic-ray measurements

Science.gov (United States)

Desilets, Darin; Zreda, Marek

2001-11-01

The wide use of cosmogenic nuclides for dating terrestrial landforms has prompted a renewed interest in characterizing the spatial distribution of terrestrial cosmic rays. Cosmic-ray measurements from neutron monitors, nuclear emulsions and cloud chambers have played an important role in developing new models for scaling cosmic-ray neutron intensities and, indirectly, cosmogenic production rates. Unfortunately, current scaling models overlook or misinterpret many of these data. In this paper, we describe factors that must be considered when using neutron measurements to determine scaling formulations for production rates of cosmogenic nuclides. Over the past 50 years, the overwhelming majority of nucleon flux measurements have been taken with neutron monitors. However, in order to use these data for scaling spallation reactions, the following factors must be considered: (1) sensitivity of instruments to muons and to background, (2) instrumental biases in energy sensitivity, (3) solar activity, and (4) the way of ordering cosmic-ray data in the geomagnetic field. Failure to account for these factors can result in discrepancies of as much as 7% in neutron attenuation lengths measured at the same location. This magnitude of deviation can result in an error on the order of 20% in cosmogenic production rates scaled from 4300 m to sea level. The shapes of latitude curves of nucleon flux also depend on these factors to a measurable extent, thereby causing additional uncertainties in cosmogenic production rates. The corrections proposed herein significantly improve our ability to transfer scaling formulations based on neutron measurements to scaling formulations applicable to spallation reactions, and, therefore, constitute an important advance in cosmogenic dating methodology.

Comets and the origin of life

Energy Technology Data Exchange (ETDEWEB)

Delsemme, A H

1981-01-01

Current understandings of the nature and evolution of the universe and of the earth are summarized as a background to the discussion of the origin of life on earth as the result of the transport of the necessary materials to earth by comets. Evidence for the origin of the universe in the Big Bang supplied by observations of the expansion of the universe and the cosmic microwave background is discussed, and the condensation of primordial matter into galaxies and stars and the chemical processes in stars converting primordial hydrogen and helium into heavy elements as the stars evolve giving rise to an interstellar medium are considered. Attention is then given to the birth of the solar system from the contraction of a dark interstellar cloud containing gas, dust and interstellar molecules, and in particular to the origin of the terrestrial planets and the cometary contributions to the terrestrial crust, oceans and atmosphere. Finally, the chronology of the universe from the Big Bang to the present and that of the earth from its formation to the present are reviewed.

Cosmic strings and cosmic structure

International Nuclear Information System (INIS)

Albrecht, A.; Brandenberger, R.; Turok, N.

1987-01-01

The paper concerns the application of the theory of cosmic strings to explain the structure of the Universe. The formation of cosmic strings in the early Universe is outlined, along with the Big Bang theory, Grand Unified theories, and the first three minutes after the Big Bang. A description is given of the shaping of the Universe by cosmic strings, including the evolution of the string. The possibility for direct observation of cosmic strings is discussed. (U.K.)

Astronomers Unveiling Life's Cosmic Origins

Science.gov (United States)

2009-02-01

Processes that laid the foundation for life on Earth -- star and planet formation and the production of complex organic molecules in interstellar space -- are yielding their secrets to astronomers armed with powerful new research tools, and even better tools soon will be available. Astronomers described three important developments at a symposium on the "Cosmic Cradle of Life" at the annual meeting of the American Association for the Advancement of Science in Chicago, IL. Chemistry Cycle The Cosmic Chemistry Cycle CREDIT: Bill Saxton, NRAO/AUI/NSF Full Size Image Files Chemical Cycle Graphic (above image, JPEG, 129K) Graphic With Text Blocks (JPEG, 165K) High-Res TIFF (44.2M) High-Res TIFF With Text Blocks (44.2M) In one development, a team of astrochemists released a major new resource for seeking complex interstellar molecules that are the precursors to life. The chemical data released by Anthony Remijan of the National Radio Astronomy Observatory (NRAO) and his university colleagues is part of the Prebiotic Interstellar Molecule Survey, or PRIMOS, a project studying a star-forming region near the center of our Milky Way Galaxy. PRIMOS is an effort of the National Science Foundation's Center for Chemistry of the Universe, started at the University of Virginia (UVa) in October 2008, and led by UVa Professor Brooks H. Pate. The data, produced by the NSF's Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, came from more than 45 individual observations totalling more than nine GigaBytes of data and over 1.4 million individual frequency channels. Scientists can search the GBT data for specific radio frequencies, called spectral lines -- telltale "fingerprints" -- naturally emitted by molecules in interstellar space. "We've identified more than 720 spectral lines in this collection, and about 240 of those are from unknown molecules," Remijan said. He added, "We're making available to all scientists the best collection of data below 50 GHz ever produced for

Life sciences on the moon

Science.gov (United States)

Horneck, G.

Despite of the fact that the lunar environment lacks essential prerequisites for supporting life, lunar missions offer new and promising opportunities to the life sciences community. Among the disciplines of interest are exobiology, radiation biology, ecology and human physiology. In exobiology, the Moon offers an ideal platform for studies related to the understanding of the principles, leading to the origin, evolution and distribution of life. These include the analysis of lunar samples and meteorites in relatively pristine conditions, radioastronomical search for other planetary systems or Search for Extra-Terrestrial Intelligence (SETI), and studies on the role of radiation in evolutionary processes and on the environmental limits for life. For radiation biology, the Moon provides an unique laboratory with built-in sources for optical as well as ionising radiation to investigate the biological importance of the various components of cosmic and solar radiation. Before establishing a lunar base, precursor missions will provide a characterisation of the radiation field, determination of depth dose distributions in different absorbers, the installation of a solar flare alert system, and a qualification of the biological efficiency of the mixed radiation environment. One of the most challenging projects falls into the domain of ecology with the establishment for the first time of an artificial ecosystem on a celestial body beyond the Earth. From this venture, a better understanding of the dynamics regulating our terrestrial biosphere is expected. It will also serve as a precursor of bioregenerative life support systems for a lunar base. The establishment of a lunar base with eventually long-term human presence will raise various problems in the fields of human physiology and health care, psychology and sociology. Protection guidelines for living in this hostile environment have to be established.

Jupiter: Cosmic Jekyll and Hyde.

Science.gov (United States)

Grazier, Kevin R

2016-01-01

It has been widely reported that Jupiter has a profound role in shielding the terrestrial planets from comet impacts in the Solar System, and that a jovian planet is a requirement for the evolution of life on Earth. To evaluate whether jovians, in fact, shield habitable planets from impacts (a phenomenon often referred to as the "Jupiter as shield" concept), this study simulated the evolution of 10,000 particles in each of the jovian inter-planet gaps for the cases of full-mass and embryo planets for up to 100 My. The results of these simulations predict a number of phenomena that not only discount the "Jupiter as shield" concept, they also predict that in a Solar System like ours, large gas giants like Saturn and Jupiter had a different, and potentially even more important, role in the evolution of life on our planet by delivering the volatile-laden material required for the formation of life. The simulations illustrate that, although all particles occupied "non-life threatening" orbits at their onset of the simulations, a significant fraction of the 30,000 particles evolved into Earth-crossing orbits. A comparison of multiple runs with different planetary configurations revealed that Jupiter was responsible for the vast majority of the encounters that "kicked" outer planet material into the terrestrial planet region, and that Saturn assisted in the process far more than has previously been acknowledged. Jupiter also tends to "fix" the aphelion of planetesimals at its orbit irrespective of their initial starting zones, which has the effect of slowing their passages through the inner Solar System, and thus potentially improving the odds of accretion of cometary material by terrestrial planets. As expected, the simulations indicate that the full-mass planets perturb many objects into the deep outer Solar System, or eject them entirely; however, planetary embryos also did this with surprising efficiency. Finally, the simulations predict that Jupiter's capacity to

Imprints to the terrestrial environment at galactic arm crossings of the solar system

Science.gov (United States)

Fahr, H. J.; Fichtner, H.; Scherer, K.; Stawicki, O.

At its itinerary through our milky way galaxy the solar system moves through highly variable interstellar environments. Due to its orbital revolution around the galactic center, the solar system also crosses periodically the spiral arms of our galactic plane and thereby expe riences pronounced enviromental changes. Gas densities, magnetic fields and galactic cosmic ray intensities are substantially higher there compared to interarm conditions. Here we present theoretical calculations describing the SN-averaged galactic cosmic ray spectrum for regions inside and outside of galactic arms which then allow to predict how periodic passages of the solar system through galactic arms should be reflected by enhanced particle irradiations of the earth`s atmosphere and by correlated terrestrial Be-10 production rates.

Direct cosmic ray muons and atmospheric neutrinos

International Nuclear Information System (INIS)

Ryazhskaya, O.G.; Volkova, L.V.; Zatsepin, G.T.

2005-01-01

A possible contribution of very short living particles (particles with life-time much shorter than that of charmed particles), for example, resonances, into cosmic ray muon and atmospheric neutrino fluxes (direct muons and neutrinos) is estimated. This contribution could become of the same order of magnitude as that from pions and kaons (conventional) already at energies of hundreds TeV and tens TeV for muons and muon neutrinos coming to the sea level in the vertical direction correspondingly. Of course, the estimation has quite a qualitative character and even it is quite arbitrary but it is necessary to keep this contribution in mind when studying EAS, cosmic ray muon component or trying to interpret data of experiments on cosmic neutrino searching at high energies

Cosmic transcendence, loneliness, and exchange of emotional support with adult children: a study among older parents in The Netherlands.

Science.gov (United States)

Sadler, E A; Braam, A W; Broese van Groenou, M I; Deeg, D J H; van der Geest, S

2006-09-01

Gerotranscendence defines a shift in meta-perspective from earlier materialistic and pragmatic concerns, toward more cosmic and transcendent ones in later life. Population-based studies that have empirically examined this concept using Tornstam's gerotranscendence scale, highlight cosmic transcendence as a core component, which includes a sense of belongingness with past and future generations. Such generative concerns may increase expectations regarding the quality of the bond with one's children in later life. This study examined whether the association between emotional support exchanged with children and feelings of loneliness later in life varied by the degree of cosmic transcendence of the older parent. Data from 1,845 older parents participating in a population-based study living in The Netherlands were analyzed from the 1995/1996 cycle of the Longitudinal Aging Study Amsterdam. Interviews included self-report measures of cosmic transcendence, loneliness, emotional support exchanged with children, health indicators, and marital status. Results indicated that a negative association between loneliness and level of emotional support exchanged with children was more pronounced among older parents with higher cosmic transcendence scores, in particular among the married. It is argued that cosmic transcendence reflects a sense of generativity and an increased emotional dependency on children in later life. Under favorable social conditions (supportive relationships with children and being married) cosmic transcendent views had a positive impact on social well-being in later life. When children no longer met emotional needs of older parents, cosmic transcendence increased feelings of loneliness.

Ultra-High-Energy Cosmic Rays

CERN Document Server

Dova, M.T.

2015-05-22

The origin of the ultra high energy cosmic rays (UHECR) with energies above E > 10 17 eV, is still unknown. The discovery of their sources will reveal the engines of the most energetic astrophysical accelerators in the universe. This is a written version of a series of lectures devoted to UHECR at the 2013 CERN-Latin-American School of High-Energy Physics. We present anintroduction to acceleration mechanisms of charged particles to the highest energies in astrophysical objects, their propagation from the sources to Earth, and the experimental techniques for their detection. We also discuss some of the relevant observational results from Telescope Array and Pierre Auger Observatory. These experiments deal with particle interactions at energies orders of magnitude higher than achieved in terrestrial accelerators.

An effective hierarchical model for the biomolecular covalent bond: an approach integrating artificial chemistry and an actual terrestrial life system.

Science.gov (United States)

Oohashi, Tsutomu; Ueno, Osamu; Maekawa, Tadao; Kawai, Norie; Nishina, Emi; Honda, Manabu

2009-01-01

Under the AChem paradigm and the programmed self-decomposition (PSD) model, we propose a hierarchical model for the biomolecular covalent bond (HBCB model). This model assumes that terrestrial organisms arrange their biomolecules in a hierarchical structure according to the energy strength of their covalent bonds. It also assumes that they have evolutionarily selected the PSD mechanism of turning biological polymers (BPs) into biological monomers (BMs) as an efficient biomolecular recycling strategy We have examined the validity and effectiveness of the HBCB model by coordinating two complementary approaches: biological experiments using existent terrestrial life, and simulation experiments using an AChem system. Biological experiments have shown that terrestrial life possesses a PSD mechanism as an endergonic, genetically regulated process and that hydrolysis, which decomposes a BP into BMs, is one of the main processes of such a mechanism. In simulation experiments, we compared different virtual self-decomposition processes. The virtual species in which the self-decomposition process mainly involved covalent bond cleavage from a BP to BMs showed evolutionary superiority over other species in which the self-decomposition process involved cleavage from BP to classes lower than BM. These converging findings strongly support the existence of PSD and the validity and effectiveness of the HBCB model.

Terrestrial Analogs to Mars

Science.gov (United States)

Farr, T. G.; Arcone, S.; Arvidson, R. W.; Baker, V.; Barlow, N. G.; Beaty, D.; Bell, M. S.; Blankenship, D. D.; Bridges, N.; Briggs, G.; Bulmer, M.; Carsey, F.; Clifford, S. M.; Craddock, R. A.; Dickerson, P. W.; Duxbury, N.; Galford, G. L.; Garvin, J.; Grant, J.; Green, J. R.; Gregg, T. K. P.; Guinness, E.; Hansen, V. L.; Hecht, M. H.; Holt, J.; Howard, A.; Keszthelyi, L. P.; Lee, P.; Lanagan, P. D.; Lentz, R. C. F.; Leverington, D. W.; Marinangeli, L.; Moersch, J. E.; Morris-Smith, P. A.; Mouginis-Mark, P.; Olhoeft, G. R.; Ori, G. G.; Paillou, P.; Reilly, J. F., II; Rice, J. W., Jr.; Robinson, C. A.; Sheridan, M.; Snook, K.; Thomson, B. J.; Watson, K.; Williams, K.; Yoshikawa, K.

2002-08-01

It is well recognized that interpretations of Mars must begin with the Earth as a reference. The most successful comparisons have focused on understanding geologic processes on the Earth well enough to extrapolate to Mars' environment. Several facets of terrestrial analog studies have been pursued and are continuing. These studies include field workshops, characterization of terrestrial analog sites, instrument tests, laboratory measurements (including analysis of Martian meteorites), and computer and laboratory modeling. The combination of all these activities allows scientists to constrain the processes operating in specific terrestrial environments and extrapolate how similar processes could affect Mars. The Terrestrial Analogs for Mars Community Panel has considered the following two key questions: (1) How do terrestrial analog studies tie in to the Mars Exploration Payload Assessment Group science questions about life, past climate, and geologic evolution of Mars, and (2) How can future instrumentation be used to address these questions. The panel has considered the issues of data collection, value of field workshops, data archiving, laboratory measurements and modeling, human exploration issues, association with other areas of solar system exploration, and education and public outreach activities.

Hazards of cosmic radiation

International Nuclear Information System (INIS)

Bonnet-Bidaud, J.M.; Dzitko, H.

2000-06-01

The main limitations on long-distance space transport is neither the energy source nor the propulsion system but appears to be the protection of cosmonauts from radiation. Cosmic radiation is made up of protons (87%), alpha particles (12%) and heavy nuclei (1%), all these particles travel through interstellar space and come from the explosion of stars at the end of their life. The earth is protected from cosmic radiation by 3 natural shields: i) the magnetic field generated by the solar wind, ii) the earth magnetic field (magnetosphere), and iii) the earth atmosphere, this elusive layer of air is equivalent to a 10 meter-high volume of water. Magnetosphere and atmosphere reduce the radiation dose by a factor 4000. According to a European directive (1996) air crews must be considered as radiation workers. (A.C.)

Uptake and transformation of arsenic during the vegetative life stage of terrestrial fungi

International Nuclear Information System (INIS)

Nearing, Michelle M.; Koch, Iris; Reimer, Kenneth J.

2015-01-01

Many species of terrestrial fungi produce fruiting bodies that contain high proportions of arsenobetaine (AB), an arsenic compound of no known toxicity. It is unknown whether fungi produce or accumulate AB from the surrounding environment. The present study targets the vegetative life stage (mycelium) of fungi, to examine the role of this stage in arsenic transformations and potential formation of AB. The mycelia of three different fungi species were cultured axenically and exposed to AB, arsenate (As(V)) and dimethylarsinoyl acetic acid for 60 days. Agaricus bisporus was additionally exposed to hypothesized precursors for AB and the exposure time to As(V) and dimethlyarsinic acid was also extended to 120 days. The mycelia of all fungi species accumulated all arsenic compounds with two species accumulating significantly more AB than other compounds. Few biotransformations were observed in these experiments indicating that it is unlikely that the mycelium of the fungus is responsible for biosynthesizing AB. - Highlights: • Mycelia of terrestrial fungi were exposed to arsenobetaine (AB) and potential precursors. • Mycelium may be selectively accumulating AB and transporting it to fruiting bodies. • Mycelium did not biosynthesize AB. - Mycelia of edible mushrooms preferentially accumulate arsenobetaine but do not biosynthesize this non-toxic arsenical

Yaku-cedar tells cosmic outbursts in ancient times. Anomalies of cosmic ray intensity in AD 774-775 and AD 993-994

International Nuclear Information System (INIS)

Miyake, Fusa; Masuda, Kimiaki

2014-01-01

Measurements of cosmogenic nuclides, which are radioisotopes produced by cosmic rays in the atmosphere, provide important information regarding extraterrestrial high-energy events. We present 14 C measurements in annual rings of Japanese cedar trees with 1- and 2-year resolutions, and a finding of two sudden increases of 14 C content by significant amount from AD 774 to 775 and AD 993 to 994. The short-term increases of radioactive nuclide production were also found in tree rings of Europe and Antarctic ice core. This strongly indicates that the anomalies were not due to local terrestrial events, but triggered by cosmic outbursts that affected the whole planet. Several conjectures have been made upon the origin of the events, e.g. nearby supernovae (∼200 pc), Galactic short gamma-ray bursts, and violent solar mass ejections like SPEs (solar proton events) or super flares. We investigated energetics and the frequencies of occurrence of the phenomena, and demonstrate that SPE is likely to be the origin of the two 14 C increase events. Astrophysical significances and impact to modern human society are also discussed. (author)

The Global Survey Method Applied to Ground-level Cosmic Ray Measurements

Science.gov (United States)

Belov, A.; Eroshenko, E.; Yanke, V.; Oleneva, V.; Abunin, A.; Abunina, M.; Papaioannou, A.; Mavromichalaki, H.

2018-04-01

The global survey method (GSM) technique unites simultaneous ground-level observations of cosmic rays in different locations and allows us to obtain the main characteristics of cosmic-ray variations outside of the atmosphere and magnetosphere of Earth. This technique has been developed and applied in numerous studies over many years by the Institute of Terrestrial Magnetism, Ionosphere and Radiowave Propagation (IZMIRAN). We here describe the IZMIRAN version of the GSM in detail. With this technique, the hourly data of the world-wide neutron-monitor network from July 1957 until December 2016 were processed, and further processing is enabled upon the receipt of new data. The result is a database of homogeneous and continuous hourly characteristics of the density variations (an isotropic part of the intensity) and the 3D vector of the cosmic-ray anisotropy. It includes all of the effects that could be identified in galactic cosmic-ray variations that were caused by large-scale disturbances of the interplanetary medium in more than 50 years. These results in turn became the basis for a database on Forbush effects and interplanetary disturbances. This database allows correlating various space-environment parameters (the characteristics of the Sun, the solar wind, et cetera) with cosmic-ray parameters and studying their interrelations. We also present features of the coupling coefficients for different neutron monitors that enable us to make a connection from ground-level measurements to primary cosmic-ray variations outside the atmosphere and the magnetosphere. We discuss the strengths and weaknesses of the current version of the GSM as well as further possible developments and improvements. The method developed allows us to minimize the problems of the neutron-monitor network, which are typical for experimental physics, and to considerably enhance its advantages.

Cosmic radiation

Energy Technology Data Exchange (ETDEWEB)

Capdevielle, J N

1984-01-01

First, the different instruments and techniques of cosmic particle detection are presented. Then the passage of the cosmic particles through the atmosphere is studied: electrons, photons, muons. The collective behavior of the different categories is also studied, the electromagnetic cascade is distinguished from the hadron cascade. Through the principal physical properties of the radiation and the medium, the ''mean'' aspects of the radiation are then successively dealt with out of the atmosphere, at different altitudes until the sea level, then at great depths. A chapter is devoted to cosmic radiation of more than 10,000 GeV, studied separately. Then solar radiation in universe is studied through their propagation in solar system and their origin. At last, the cosmic radiation effects are studied in environment (cosmic biophysics) and some applications of cosmic radiation are presented.

Snowpack snow water equivalent measurement using the attenuation of cosmic gamma radiation

International Nuclear Information System (INIS)

Osterhuber, R.; Condreva, K.

1998-01-01

Incoming, background cosmic radiation constantly fluxes through the earth's atmosphere. The high energy gamma portion of this radiation penetrates many terrestrial objects, including the winter snowpack. The attenuation of this radiation is exponentially related to the mass of the medium through which it penetrates. For the past three winters, a device measuring cosmic gamma radiation--and its attenuation through snow--has been installed at the Central Sierra Snow Laboratory, near Donner Pass, California. This gamma sensor, measuring energy levels between 5 and 15 MeV, has proved to be an accurate, reliable, non-invasive, non-mechanical instrument with which to measure the total snow water equivalent of a snowpack. This paper analyzes three winters' worth of data and discusses the physics and practical application of the sensor for the collection of snow water equivalent data from a remote location

Cosmic Education: Formation of a Planetary and Cosmic Personality

Directory of Open Access Journals (Sweden)

Bazaluk Oleg

2012-04-01

Full Text Available The major stages of development of cosmic pedagogy have been researched. Based on the achievements of the modern neurosciences as well as of psychology, cosmology, and philosophy, the authors provide their reasoning for the cosmic education and its outlooks for the educational systems of the world. Through the studies of how important human mind is for the Earth and the cosmos and by researching the evolution of human mind within the structure of the Universe, the authors create a more advanced scientific and philosophic basis for the cosmic education where the subject is a comprehensive process of formation and directed progress of both an individual mind and a conglomerate of minds called the "psychospace". The cosmic education researches the permanent progress of the intelligent matter of the Earth. The purpose of the cosmic education has been determined as formation of a planetary and cosmic personality. According to the authors, a planetary and cosmic personality is a harmony of mind, soul, and body, and such harmony is directed to use the internal creative potential of mind to the benefit of the intelligent matter of the entire Earth and the cosmos. The properties of such a planetary and cosmic personality are being improved continuously; they are a sample (the ideal of the cosmic pedagogy and the image of a human being of the future. Through the usage of the entire potential and art of upbringing and educating, the cosmic pedagogy is called to embody the major properties of the image of a human being of the future in the new generations of minds and to form a planetary and cosmic personality capable of self-actualization to the benefit of the permanent progress of the intelligent matter.

Key scientific problems from Cosmic Ray History

Science.gov (United States)

Lev, Dorman

2016-07-01

young scientist from the Graz University, started to investigate how γ-radiations change their intensity with the distance from their sources, i.e. from the ground. When he performed his historical experiments on balloons in 1911-1912, it was found that at the beginning (up to approximately one km) ionization did not change, but with increase of the altitude for up to 4 - 5 km, the ionization rate escalates several times. Victor Hess drew a conclusion that some new unknown source of ionization of extra terrestrial origin exists. He named it 'high altitude radiation'. 5. Many scientists did not agree with this conclusion and tried to prove that the discovered new radiation has terrestrial origin (e.g., radium and other emanations from radioactive substances in the ground, particle acceleration up to high energies during thunderstorms, and so on). However, a lot of experiments showed that Victor Hess's findings are right: the discovered new radiation has extra terrestrial origin. 6. In 1926 the great American scientist Robert Millikan named them 'cosmic rays': cosmic as coming from space, and rays because it was generally wrongly accepted at those time that the new radiation mostly consisted of γ-rays. Robert Millikan believed that God exists and continues to work: in space God has creates He atoms from four atoms of H with the generation high energy gamma rays (in contradiction with physical laws, as this reaction can occur only at very high temperature and great density, e.g., as inside stars). 7. On this problem, interesting to many people, there was a famous public discussion between two Nobel laureates Arthur Compton and Robert Millikan, widely reported in newspapers. Only after a lot of latitude surveys in the 1930s, organized mostly by Compton and Millikan, it became clear that 'cosmic rays' are mostly not γ-rays, but rather charged particles (based on Störmer's theory about behavior of charged energetic particles in the geomagnetic field, developed in 1910

Solar activity and terrestrial climate: an analysis of some purported correlations

DEFF Research Database (Denmark)

Laut, Peter

2003-01-01

claimed to support solar hypotheses. My analyses show that the apparent strong correlations displayed on these graphs have been obtained by an incorrect handling of the physical data. Since the graphs are still widely referred to in the literature and their misleading character has not yet been generally......The last decade has seen a revival of various hypotheses claiming a strong correlation between solar activity and a number of terrestrial climate parameters: Links between cosmic rays and cloud cover, first total cloud cover and then only low clouds, and between solar cycle lengths and Northern...... the existence of important links between solar activity and terrestrial climate. Such links have over the years been demonstrated by many authors. The sole objective of the present analysis is to draw attention to the fact that some of the widely publicized, apparent correlations do not properly reflect...

Observation of terrestrial orbital motion using the cosmic-ray Compton-Getting effect

International Nuclear Information System (INIS)

Cutler, D.J.; Groom, D.E.

1986-01-01

Using underground observations, the authors have found a small diurnal amplitude modulation of the cosmic-ray muon intensity which agrees in amplitude and phase with a first-order relativistic effect due to the Earth's motion, as discussed by Compton and Getting :1935, Phys. Rev., 47, 817:. Analysis of the arrival times of 5x10 8 muons during a period of 5.4 yr yields a fractional amplitude variation of 2.5sub(-0.6) sup(+0.7) x 10 -4 , with a maximum near dawn, at 08:18+-1.0 h local mean solar time (LT). The expected amplitude is 3.40 x 10 -4 , with the maximum at 06:00LT. (author)

The puzzle of the ultra-high energy cosmic rays

CERN Document Server

Tkachev, I I

2003-01-01

In early years the cosmic ray studies were ahead of accelerator research, starting from the discovery of positrons, through muons, to that of pions and strange particles. Today we are facing the situation that the puzzling saga of cosmic rays of the highest energies may again unfold in the discovery of new physics, now beyond the Standard Model; or it may bring to life an "extreme" astrophysics. After a short review of the Greisen-Zatsepin-Kuzmin puzzle, I discuss different models which were suggested for its resolution. Are there any hints pointing to the correct model? I argue that the small-scale clustering of arrival directions of cosmic rays gives a clue, and BL Lacs are the probable sources of the observed events. (58 refs).

Does terrestrial epidemiology apply to marine systems?

Science.gov (United States)

McCallum, Hamish I.; Kuris, Armand M.; Harvell, C. Drew; Lafferty, Kevin D.; Smith, Garriet W.; Porter, James

2004-01-01

Most of epidemiological theory has been developed for terrestrial systems, but the significance of disease in the ocean is now being recognized. However, the extent to which terrestrial epidemiology can be directly transferred to marine systems is uncertain. Many broad types of disease-causing organism occur both on land and in the sea, and it is clear that some emergent disease problems in marine environments are caused by pathogens moving from terrestrial to marine systems. However, marine systems are qualitatively different from terrestrial environments, and these differences affect the application of modelling and management approaches that have been developed for terrestrial systems. Phyla and body plans are more diverse in marine environments and marine organisms have different life histories and probably different disease transmission modes than many of their terrestrial counterparts. Marine populations are typically more open than terrestrial ones, with the potential for long-distance dispersal of larvae. Potentially, this might enable unusually rapid propagation of epidemics in marine systems, and there are several examples of this. Taken together, these differences will require the development of new approaches to modelling and control of infectious disease in the ocean.

Impact of cosmic rays and solar energetic particles on the Earth’s ionosphere and atmosphere

Czech Academy of Sciences Publication Activity Database

Velinov, P. I. Y.; Asenovski, S.; Kudela, K.; Laštovička, Jan; Mateev, L.; Mishev, A.; Tonev, P.

2013-01-01

Roč. 3, 26 March (2013), A14/1-A14/17 ISSN 2115-7251 Grant - others:European COST Action(XE) ES0803 Institutional support: RVO:68378289 Keywords : cosmic rays * solar energetic particles * ionization * ionosphere * atmosphere * solar activity * solar-terrestrial relationships Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 2.519, year: 2013 http://www.swsc-journal.org/articles/swsc/abs/2013/01/swsc120040/swsc120040.html

Carl Sagan's Cosmic Connection

Science.gov (United States)

Sagan, Carl; Agel, Jerome

2000-08-01

Foreword Freeman Dyson; Personal reflections Ann Druyan; Preface; Part I. Cosmic Perspective: 1. A transitional animal; 2. The Unicorn of Cetus; 3. A message from earth; 4. A message to earth; 5. Experiments in utopias; 6. Chauvinism; 7. Space exploration as a human enterprise I. The scientific interest; 8. Space exploration as a human enterprise II. The public interest; 9. Space exploration as a human enterprise III. The historical interest; Part II. The Solar System: 10. On teaching the first grade; 11. 'The ancient and legendary Gods of old'; 12. The Venus detective story; 13. Venus is hell; 14. Science and 'intelligence'; 15. The moons of Barsoom; 16. The mountains of Mars I. Observations from earth; 17. The mountains of Mars II. Observations from space; 18. The canals of Mars; 19. The lost pictures of Mars; 20. The Ice Age and the cauldron; 21. Beginnings and ends of the Earth; 22. Terraforming the plants; 23. The exploration and utlization of the solar system; Part III. Beyond the Solar System: 24. Some of my best friends are dolphins; 25. 'Hello, central casting? Send me twenty extraterrestrials'; 26. The cosmic connection; 27. Extraterrestrial life: an idea whose time has come; 28. Has the Earth been visited?; 29. A search strategy for detecting extraterrestrial intelligence; 30. If we succeed 31. Cables, drums, and seashells; 32. The night freight to the stars; 33. Astroengineering; 34. Twenty questions: a classification of cosmic civilisations; 35. Galactic cultural exchanges; 36. A passage to elsewhere; 37. Starfolk I. A Fable; 38. Starfolk II. A future; 39. Starfolk III. The cosmic Cheshire cats; Epilog David Morrison; Index.

Our cosmic habitat

CERN Document Server

Rees, Martin

2001-01-01

Our universe seems strangely 'biophilic,' or hospitable to life. Is this providence or coincidence? According to Martin Rees, the answer depends on the answer to another question, the one posed by Einstein's famous remark: 'What interests me most is whether God could have made the world differently.' This highly engaging book centres on the fascinating consequences of the answer being 'yes'. Rees explores the notion that our universe is just part of a vast 'multiverse,' or ensemble of universes, in which most of the other universes are lifeless. What we call the laws of nature would then be local by laws, imposed in the aftermath of our own Big Bang. In this scenario, our cosmic habitat would be a special, possibly unique universe where the prevailing laws of physics allowed life to emerge.

The potential of detecting intermediate-scale biomass and canopy interception in a coniferous forest using cosmic-ray neutron intensity measurements and neutron transport modeling

Science.gov (United States)

Andreasen, M.; Looms, M. C.; Bogena, H. R.; Desilets, D.; Zreda, M. G.; Sonnenborg, T. O.; Jensen, K. H.

2014-12-01

The water stored in the various compartments of the terrestrial ecosystem (in snow, canopy interception, soil and litter) controls the exchange of the water and energy between the land surface and the atmosphere. Therefore, measurements of the water stored within these pools are critical for the prediction of e.g. evapotranspiration and groundwater recharge. The detection of cosmic-ray neutron intensity is a novel non-invasive method for the quantification of continuous intermediate-scale soil moisture. The footprint of the cosmic-ray neutron probe is a hemisphere of a few hectometers and subsurface depths of 10-70 cm depending on wetness. The cosmic-ray neutron method offers measurements at a scale between the point-scale measurements and large-scale satellite retrievals. The cosmic-ray neutron intensity is inversely correlated to the hydrogen stored within the footprint. Overall soil moisture represents the largest pool of hydrogen and changes in the soil moisture clearly affect the cosmic-ray neutron signal. However, the neutron intensity is also sensitive to variations of hydrogen in snow, canopy interception and biomass offering the potential to determine water content in such pools from the signal. In this study we tested the potential of determining canopy interception and biomass using cosmic-ray neutron intensity measurements within the framework of the Danish Hydrologic Observatory (HOBE) and the Terrestrial Environmental Observatories (TERENO). Continuous measurements at the ground and the canopy level, along with profile measurements were conducted at towers at forest field sites. Field experiments, including shielding the cosmic-ray neutron probes with cadmium foil (to remove lower-energy neutrons) and measuring reference intensity rates at complete water saturated conditions (on the sea close to the HOBE site), were further conducted to obtain an increased understanding of the physics controlling the cosmic-ray neutron transport and the equipment used

Acceleration of galactic cosmic rays in shock waves

International Nuclear Information System (INIS)

Lagage, P.O.

1981-06-01

The old problem of the origin of cosmic rays has triggered off fresh interest owing to the discovery of a new model which enables a lot of energy to be transferred to a small number of particles on the one hand and the discovery of the coronal environment in which this transfer occurs, on the other. In this paper, interest is taken in the galactic cosmic rays and an endeavour is made to find out if the model can reveal the existence of cosmic rays over a wide energy range. The existence of an energy break, predicted by the model, was recognized fairly early but, in the literature, it varies from 30 GeV ro 10 6 GeV according to the authors. A study has been made of the two main causes of an energy break: the sphericity of the shock and the life time of the shock wave [fr

Technologies for Low Frequency Radio Observations of the Cosmic Dawn

Science.gov (United States)

Jones, Dayton L.

2014-01-01

The Jet Propulsion Laboratory (JPL) is developing concepts and technologies for low frequency radio astronomy space missions aimed at observing highly redshifted neutral Hydrogen from the Dark Ages. This is the period of cosmic history between the recombination epoch when the microwave background radiation was produced and the re-ionization of the intergalactic medium by the first generation of stars (Cosmic Dawn). This period, at redshifts greater than about 20, is a critical epoch for the formation and evolution of large-scale structure in the universe. The 21-cm spectral line of Hydrogen provides the most promising method for directly studying the Dark Ages, but the corresponding frequencies at such large redshifts are only tens of MHz and thus require space-based observations to avoid terrestrial RFI and ionospheric absorption and refraction. This paper reports on the status of several low frequency technology development activities at JPL, including deployable bi-conical dipoles for a planned lunar-orbiting mission, and both rover-deployed and inflation-deployed long dipole antennas for use on the lunar surface.

Garden of cosmic speculation

CERN Document Server

Jencks, Charles

2005-01-01

This book tells the story of one of the most important gardens in Europe, created by the architectural critic and designer Charles Jencks and his late wife, the landscape architect and author Maggie Keswick. The Garden of Cosmic Speculation is a landscape that celebrates the new sciences of complexity and chaos theory and consists of a series of metaphors exploring the origins, the destiny and the substance of the Universe. The book is illustrated with year-round photography, bringing the garden's many dimensions vividly to life.

Constraints on a potential aerial biosphere on Venus: I. Cosmic rays

Science.gov (United States)

Dartnell, Lewis R.; Nordheim, Tom Andre; Patel, Manish R.; Mason, Jonathon P.; Coates, Andrew J.; Jones, Geraint H.

2015-09-01

While the present-day surface of Venus is certainly incompatible with terrestrial biology, the planet may have possessed oceans in the past and provided conditions suitable for the origin of life. Venusian life may persist today high in the atmosphere where the temperature and pH regime is tolerable to terrestrial extremophile microbes: an aerial habitable zone. Here we argue that on the basis of the combined biological hazard of high temperature and high acidity this habitable zone lies between 51 km (65 °C) and 62 km (-20 °C) altitude. Compared to Earth, this potential venusian biosphere may be exposed to substantially more comic ionising radiation: Venus has no protective magnetic field, orbits closer to the Sun, and the entire habitable region lies high in the atmosphere - if this narrow band is sterilised there is no reservoir of deeper life that can recolonise afterwards. Here we model the propagation of particle radiation through the venusian atmosphere, considering both the background flux of high-energy galactic cosmic rays and the transient but exceptionally high-fluence bursts of extreme solar particle events (SPE), such as the Carrington Event of 1859 and that inferred for AD 775. We calculate the altitude profiles of both energy deposition into the atmosphere and the absorbed radiation dose to assess this astrophysical threat to the potential high-altitude venusian biosphere. We find that at the top of the habitable zone (62 km altitude; 190 g/cm2 shielding depth) the radiation dose from the modelled Carrington Event with a hard spectrum (matched to the February 1956 SPE) is over 18,000 times higher than the background from GCR, and 50,000 times higher for the modelled 775 AD event. However, even though the flux of ionising radiation can be sterilizing high in the atmosphere, the total dose delivered at the top of the habitable zone by a worst-case SPE like the 775 AD event is 0.09 Gy, which is not likely to present a significant survival challenge

Oscillations in the open solar magnetic flux with a period of 1.68 years: imprint on galactic cosmic rays and implications for heliospheric shielding

Directory of Open Access Journals (Sweden)

A. Rouillard

2004-12-01

Full Text Available An understanding of how the heliosphere modulates galactic cosmic ray (GCR fluxes and spectra is important, not only for studies of their origin, acceleration and propagation in our galaxy, but also for predicting their effects (on technology and on the Earth's environment and organisms and for interpreting abundances of cosmogenic isotopes in meteorites and terrestrial reservoirs. In contrast to the early interplanetary measurements, there is growing evidence for a dominant role in GCR shielding of the total open magnetic flux, which emerges from the solar atmosphere and enters the heliosphere. In this paper, we relate a strong 1.68-year oscillation in GCR fluxes to a corresponding oscillation in the open solar magnetic flux and infer cosmic-ray propagation paths confirming the predictions of theories in which drift is important in modulating the cosmic ray flux. Key words. Interplanetary physics (Cosmic rays, Interplanetary magnetic fields

Observation of superheavy primary cosmic ray nuclei with solid state track detectors and x-ray films

International Nuclear Information System (INIS)

Doke, Tadayoshi; Hayashi, Takayoshi; Ito, Kensai; Yanagimachi, Tomoki; Kobayashi, Shigeru.

1977-01-01

The measurements of energy spectra and the nuclear charge distribution of superheavy nuclei heavier than iron in primary cosmic ray can provide information on the origin, propagation and life time of the cosmic ray. Since incident particles are in the region of relativistic velocity (the low energy cosmic ray below the cutoff energy is forbidden from entering), the charges of cosmic ray nuclei can be determined without knowing the energy of particles. The balloon-borne solid state track detector and plastic and X-ray films were employed for the detection of superheavy cosmic ray, and the five events were detected with the cellulose nitrate film. The flux of superheavy nuclei is predicted from the present analysis. (Yoshimori, M.)

Cosmic void clumps

Science.gov (United States)

Lares, M.; Luparello, H. E.; Garcia Lambas, D.; Ruiz, A. N.; Ceccarelli, L.; Paz, D.

2017-10-01

Cosmic voids are of great interest given their relation to the large scale distribution of mass and the way they trace cosmic flows shaping the cosmic web. Here we show that the distribution of voids has, in consonance with the distribution of mass, a characteristic scale at which void pairs are preferentially located. We identify clumps of voids with similar environments and use them to define second order underdensities. Also, we characterize its properties and analyze its impact on the cosmic microwave background.

Application of the idea of morphism in solar-terrestrial physics and space weather

International Nuclear Information System (INIS)

Mateev, Lachezar; Tassev, Yordan; Velinov, Peter

2016-01-01

The actual problems of solar-terrestrial physics, in particular of space weather are related to the prediction of the space environment state and are solved by means of different analyses and models. In the present work we introduce a new mathematical approach to the study of physical processes in the system Sun-Earth. For example, in the ionization of the ionosphere and atmosphere under the influence of cosmic rays a model is used that applies the principle of homomorphism. When calculating the parameters of space weather such as solar wind, interplanetary magnetic fields, Earth’s magnetosphere, geomagnetic storms and others, the introduction and application of mathematical objects is appropriate: morphisms, groups, categories, monads, functors, natural transformations and others. Such an approach takes into account the general laws of physical processes in the system Sun – Earth and helps in their testing and calculation. It is useful for such complex systems and processes as these in the solar-terrestrial physics and space weather. Some methods for algebraic structures can be introduced. These methods give the possibility for axiomatization of the physical data reality and the application of algebraic methods for their processing. Here we give the base for the transformation from the algebraic theory of categories and morphisms to the physical structure of concepts and data. Such problems are principally considered in the proposed work. Key words: pace weather, space radiation environment, solar effects, forecasting, energetic solar particles, cosmic rays

Cosmic rays

International Nuclear Information System (INIS)

Tkachev, I.I.

2014-01-01

In this talk I will review results of cosmic ray observations at the highest energies. This year the new results on energy spectra, composition and the study of arrival directions of cosmic ray primaries came from the Telescope Array collaboration. I present these results in comparison with measurements done by other recent experiments and discuss their implications for the search of cosmic ray sources. Some related results in gamma-ray astronomy and selected recent advances in theory are also covered. (author)

The Importance of Water for Life

Science.gov (United States)

Westall, Frances; Brack, André

2018-03-01

Liquid water is essential for life as we know it, i.e. carbon-based life. Although other compound-solvent pairs that could exist in very specific physical environments could be envisaged, the elements essential to carbon and water-based life are among the most common in the universe. Carbon molecules and liquid water have physical and chemical properties that make them optimised compound-solvent pairs. Liquid water is essential for important prebiotic reactions. But equally important for the emergence of life is the contact of carbon molecules in liquid water with hot rocks and minerals. We here review the environmental conditions of the early Earth, as soon as it had liquid water at its surface and was habitable. Basing our approach to life as a "cosmic phenomenon" (de Duve 1995), i.e. a chemical continuum, we briefly address the various hypotheses for the origin of life, noting their relevance with respect to early environmental conditions. It appears that hydrothermal environments were important in this respect. We continue with the record of early life noting that, by 3.5 Ga, when the sedimentary environment started being well-preserved, anaerobic life forms had colonised all habitable microenvironments from the sea floor to exposed beach environments and, possibly, in the photic planktonic zone of the sea. Life on Earth had also evolved to the relatively sophisticated stage of anoxygenic photosynthesis. We conclude with an evaluation of the potential for habitability and colonisation of other planets and satellites in the Solar System, noting that the most common life forms in the Solar System and probably in the Universe would be similar to terrestrial chemotrophs whose carbon source is either reduced carbon or CO2 dissolved in water and whose energy would be sourced from oxidized carbon, H2, or other transition elements.

Cosmic transcendence, loneliness and exchange of emotional support with adult children: A study among older parents in the Netherlands

NARCIS (Netherlands)

Sadler, E.; Braam, A.J.; Broese Van Groenou, M.I.; Deeg, D.J.H.; van der Geest, S.

2006-01-01

Gerotranscendence defines a shift in meta-perspective from earlier materialistic and pragmatic concerns, toward more cosmic and transcendent ones in later life. Population-based studies that have empirically examined this concept using Tornstam's gerotranscendence scale, highlight cosmic

TERRESTRIAL EFFECTS OF NEARBY SUPERNOVAE IN THE EARLY PLEISTOCENE

Energy Technology Data Exchange (ETDEWEB)

Thomas, B. C.; Engler, E. E. [Department of Physics and Astronomy, Washburn University, Topeka, KS 66621 (United States); Kachelrieß, M. [Institutt for fysikk, NTNU, Trondheim (Norway); Melott, A. L. [Department of Physics and Astronomy, University of Kansas, Lawrence, KS 66045 (United States); Overholt, A. C. [Department of Science and Mathematics, MidAmerica Nazarene University, Olathe, KS 66062 (United States); Semikoz, D. V., E-mail: brian.thomas@washburn.edu [APC, Universite Paris Diderot, CNRS/IN2P3, CEA/IRFU, Observatoire de Paris, Sorbonne Paris Cite, F-119 75205 Paris (France)

2016-07-20

Recent results have strongly confirmed that multiple supernovae happened at distances of ∼100 pc, consisting of two main events: one at 1.7–3.2 million years ago, and the other at 6.5–8.7 million years ago. These events are said to be responsible for excavating the Local Bubble in the interstellar medium and depositing {sup 60}Fe on Earth and the Moon. Other events are indicated by effects in the local cosmic ray (CR) spectrum. Given this updated and refined picture, we ask whether such supernovae are expected to have had substantial effects on the terrestrial atmosphere and biota. In a first look at the most probable cases, combining photon and CR effects, we find that a supernova at 100 pc can have only a small effect on terrestrial organisms from visible light and that chemical changes such as ozone depletion are weak. However, tropospheric ionization right down to the ground, due to the penetration of ≥TeV CRs, will increase by nearly an order of magnitude for thousands of years, and irradiation by muons on the ground and in the upper ocean will increase twentyfold, which will approximately triple the overall radiation load on terrestrial organisms. Such irradiation has been linked to possible changes in climate and increased cancer and mutation rates. This may be related to a minor mass extinction around the Pliocene-Pleistocene boundary, and further research on the effects is needed.

Community Decadal Panel for Terrestrial Analogs to Mars

Science.gov (United States)

Barlow, N. G.; Farr, T.; Baker, V. R.; Bridges, N.; Carsey, F.; Duxbury, N.; Gilmore, M. S.; Green, J. R.; Grin, E.; Hansen, V.; Keszthelyi, L.; Lanagan, P.; Lentz, R.; Marinangeli, L.; Morris, P. A.; Ori, G. G.; Paillou, P.; Robinson, C.; Thomson, B.

2001-11-01

It is well recognized that interpretations of Mars must begin with the Earth as a reference. The most successful comparisons have focused on understanding geologic processes on the Earth well enough to extrapolate to Mars' environment. Several facets of terrestrial analog studies have been pursued and are continuing. These studies include field workshops, characterization of terrestrial analog sites for Mars, instrument tests, laboratory measurements (including analysis of martian meteorites), and computer and laboratory modeling. The combination of all these activities allows scientists to constrain the processes operating in specific terrestrial environments and extrapolate how similar processes could affect Mars. The Terrestrial Analogs for Mars Community Panel is considering the following two key questions: (1) How do terrestrial analog studies tie in to the MEPAG science questions about life, past climate, and geologic evolution of Mars, and (2) How can future instrumentation be used to address these questions. The panel is considering the issues of data collection, value of field workshops, data archiving, laboratory measurements and modeling, human exploration issues, association with other areas of solar system exploration, and education and public outreach activities.

The weak force and SETH: The search for Extra-Terrestrial Homochirality

Science.gov (United States)

MacDermott, Alexandra J.

1996-07-01

We propose that a search for extra-terrestrial life can be approached as a Search for Extra-Terrestrial Homochirality-SETH. Homochirality is probably a pre-condition for life, so a chiral influence may be required to get life started. We explain how the weak force mediated by the Z0 boson gives rise to a small parity-violating energy difference (PVED) between enantiomers, and discuss how the resulting small excess of the more stable enantiomer may be amplified to homochirality. Titan and comets are good places to test for emerging pre-biotic homochirality, while on Mars there may be traces of homochirality as a relic of extinct life. Our calculations of the PVED show that the natural L-amino acids are indeed more stable than their enantiomers, as are several key D-sugars and right-hand helical DNA. Thiosubstituted DNA analogues show particularly large PVEDs. L-quartz is also more stable than D-quartz, and we believe that further crystal counts should be carried out to establish whether reported excesses of L quartz are real. Finding extra-terrestrial molecules of the same hand as on Earth would lend support to the universal chiral influence of the weak force. We describe a novel miniaturized space polarimeter, called the SETH Cigar, which we hope to use to detect optical rotation on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. Even if we do not find the same hand as on Earth, finding extra-terrestrial optical rotation would be of enormous importance as it would still be the homochiral signature of life.

The Concept of Cosmic Tree in Armenian and Iranian Cosmologies

Science.gov (United States)

Farmanyan, S. V.; Mickaelian, A. M.

2016-09-01

Cosmic Tree or Tree of Life is a common motif in various world theologies, mythologies, and philosophies. In the present study we focus on Armenian and Iranian Cosmic Tree. In ancient Armenia, the Tree of Life (Կենաց Ծառ) is a religious symbol and is drawn on walls of fortresses and carved on the armour of warriors. According to ancient Armenians the center of the Universe is located at the crown of the tree or the column, which is the closest to the sky. We explore the idea of cosmic tree in the riddles, prayers, medieval rituals and miniatures. In the riddles, the tree mostly symbolizes the celestial phenomena (Sun, Stars, and Heavens), different units of time (years, months, weeks, days, and seasons), the people, Jerusalem, the apostles and Jesus Christ. The branches of the tree were equally divided on the right and left sides of the stem, with each branch having one leaf, and one leaf on the apex of the tree. Servants stood on each side of the tree with one of their hands up as if they are taking care of the tree. In pre-Islamic Persian mythology, the Gaokerena world tree is a large, sacred Haoma tree which bears all seeds. Ahriman created a frog to invade the tree and destroy it, aiming at preventing all trees from growing on the Earth. As a reaction, God (Ahura Mazda) created two kar fish staring at the frog to guard the tree. The concept of world tree in Persian Mythology is very closely related to the concept of the Tree of Life. Another related issue in ancient mythology of Iran is the myth of Mashya and Mashyane, two trees who were the ancestors of all living beings. This myth can be considered as a prototype for the creation myth where living beings are created by Gods (who have human forms). We come to the conclusion that in both cultures, no matter of the present different religions, the perception of Cosmic Tree is interconnected to the life on our planet and served as a metaphor for common descent in the evolutionary sense.

Cosmic Evolution: The History of an Idea

Science.gov (United States)

Dick, S. J.

2004-12-01

Cosmic evolution has become the conceptual framework within which modern astronomy is undertaken, and is the guiding principle of major NASA programs such as Origins and Astrobiology. While there are 19th- and early 20th century antecedents, as in the work of Robert Chambers, Herbert Spencer and Lawrence Henderson, it was only at mid-20th century that full-blown cosmic evolution began to be articulated and accepted as a research paradigm extending from the Big Bang to life, intelligence and the evolution of culture. Harlow Shapley was particularly important in spreading the idea to the public in the 1950s, and NASA embraced the idea in the 1970s as part of its SETI program and later its exobiology and astrobiology programs. Eric Chaisson, Carl Sagan and others were early proponents of cosmic evolution, and it continues to be elaborated in ever more subtle form as a research program and a philosophy. It has even been termed "Genesis for the 21st century." This paper documents the origin and development of the idea and offers a glimpse of where it could lead if cultural evolution is taken seriously, possibly leading to the concept of a postbiological universe.

Linking animals aloft with the terrestrial landscape

Science.gov (United States)

Buler, Jeffrey J.; Barrow, Wylie; Boone, Matthew; Dawson, Deanna K.; Diehl, Robert H.; Moore, Frank R.; Randall, Lori A.; Schreckengost, Timothy; Smolinsky, Jaclyn A.

2018-01-01

Despite using the aerosphere for many facets of their life, most flying animals (i.e., birds, bats, some insects) are still bound to terrestrial habitats for resting, feeding, and reproduction. Comprehensive broad-scale observations by weather surveillance radars of animals as they leave terrestrial habitats for migration or feeding flights can be used to map their terrestrial distributions either as point locations (e.g., communal roosts) or as continuous surface layers (e.g., animal densities in habitats across a landscape). We discuss some of the technical challenges to reducing measurement biases related to how radars sample the aerosphere and the flight behavior of animals. We highlight a recently developed methodological approach that precisely and quantitatively links the horizontal spatial structure of birds aloft to their terrestrial distributions and provides novel insights into avian ecology and conservation across broad landscapes. Specifically, we present case studies that (1) elucidate how migrating birds contend with crossing ecological barriers and extreme weather events, (2) identify important stopover areas and habitat use patterns of birds along their migration routes, and (3) assess waterfowl response to wetland habitat management and restoration. These studies aid our understanding of how anthropogenic modification of the terrestrial landscape (e.g., urbanization, habitat management), natural geographic features, and weather (e.g., hurricanes) can affect the terrestrial distributions of flying animals.

Effects of climate change on terrestrial animals [Chapter 9

Science.gov (United States)

Megan M. Friggens; Mary I. Williams; Karen E. Bagne; Tosha T. Wixom; Samuel A. Cushman

2018-01-01

The Intermountain Adaptation Partnership (IAP) region encompasses a high diversity of grassland, shrubland, and forest habitats across a broad range of elevational gradients, supporting high biodiversity in the interior western United States. Terrestrial species comprise a wide range of life forms, each expressing varying levels of habitat specialization and life...

Our Cosmic Insignificance

Science.gov (United States)

Kahane, Guy

2014-01-01

The universe that surrounds us is vast, and we are so very small. When we reflect on the vastness of the universe, our humdrum cosmic location, and the inevitable future demise of humanity, our lives can seem utterly insignificant. Many philosophers assume that such worries about our significance reflect a banal metaethical confusion. They dismiss the very idea of cosmic significance. This, I argue, is a mistake. Worries about cosmic insignificance do not express metaethical worries about objectivity or nihilism, and we can make good sense of the idea of cosmic significance and its absence. It is also possible to explain why the vastness of the universe can make us feel insignificant. This impression does turn out to be mistaken, but not for the reasons typically assumed. In fact, we might be of immense cosmic significance—though we cannot, at this point, tell whether this is the case. PMID:25729095

George's cosmic treasure hunt

CERN Document Server

Hawking, Lucy; Parsons, Gary

2009-01-01

George and Annie explore the galaxy in this cosmic adventure from Stephen Hawking and Lucy Hawking, complete with essays from Professor Hawking about the latest in space travel. George is heartbroken when he learns that his friend Annie and her father are moving to the US. Eric has a new job working for the space program, looking for signs of life in the Universe. Eric leaves George with a gift—a book called The User’s Guide to the Universe. But Annie and Eric haven’t been gone for very long when Annie believes that she is being contacted by aliens, who have a terrible warning for her. George joins her in the US to help her with her quest—and before he knows it, he, Annie, Cosmos, and Annie’s annoying cousin Emmett have been swept up in a cosmic treasure hunt, spanning the whole galaxy and beyond. Lucy Hawking's own experiences in zero-gravity flight and interviews with astronauts at Cape Kennedy and the Johnson Space Center lend the book a sense of realism and excitement that is sure to fire up ima...

Stardust the cosmic seeds of life

CERN Document Server

Kwok, Sun

2013-01-01

How did life originate on Earth? For over 50 years, scientists believed that life was the result of a chemical reaction involving simple molecules such as methane and ammonia cooking in a primordial soup. Recent space observations have revealed that old stars are capable of making very complex organic compounds. At some point in their evolution, stars eject those organics and spread them all over the Milky Way galaxy. There is evidence that these organic dust particles actually reached the early Solar System. Through bombardments by comets and asteroids, the young Earth inherited significant amounts of stardust. Was the development of life assisted by the arrival of these extraterrestrial materials?   In this book, the author describes stunning discoveries in astronomy and solar system science made over the last 10 years that have yielded a new perspective on the origin of life.   Other interesting topics discussed in this book   The discovery of diamonds and other gemstones in space The origin of oil Neon...

A grey incidence algorithm to detect high-Z material using cosmic ray muons

Science.gov (United States)

He, W.; Xiao, S.; Shuai, M.; Chen, Y.; Lan, M.; Wei, M.; An, Q.; Lai, X.

2017-10-01

Muon scattering tomography (MST) is a method for using cosmic muons to scan cargo containers and vehicles for special nuclear materials. However, the flux of cosmic ray muons is low, in the real life application, the detection has to be done a short timescale with small numbers of muons. In this paper, we present a novel approach to detection of special nuclear material by using cosmic ray muons. We use the degree of grey incidence to distinguish typical waste fuel material, uranium, from low-Z material, medium-Z material and other high-Z materials of tungsten and lead. The result shows that using this algorithm, it is possible to detect high-Z materials with an acceptable timescale.

Cosmic Microwave Background Timeline

Science.gov (United States)

Cosmic Microwave Background Timeline 1934 : Richard Tolman shows that blackbody radiation in an will have a blackbody cosmic microwave background with temperature about 5 K 1955: Tigran Shmaonov anisotropy in the cosmic microwave background, this strongly supports the big bang model with gravitational

Light scattering by cosmic particles

NARCIS (Netherlands)

Hovenier, J.W.; Min, M.

2008-01-01

We define cosmic particles as particles outside the Earth. Two types of cosmic particles can be distinguished, namely liquid and solid particles. The solid particles are often called grains or cosmic dust particles. Cosmic particles occur in a great variety of astronomical objects and environments.

Cosmic Origins Program Annual Technology Report

Science.gov (United States)

Pham, Bruce Thai; Neff, Susan Gale

2015-01-01

What is the Cosmic Origins (COR) Program? From ancient times, humans have looked up at the night sky and wondered: Are we alone? How did the universe come to be? How does the universe work? COR focuses on the second question. Scientists investigating this broad theme seek to understand the origin and evolution of the universe from the Big Bang to the present day, determining how the expanding universe grew into a grand cosmic web of dark matter enmeshed with galaxies and pristine gas, forming, merging, and evolving over time. COR also seeks to understand how stars and planets form from clouds in these galaxies to create the heavy elements that are essential to life starting with the first generation of stars to seed the universe, and continuing through the birth and eventual death of all subsequent generations of stars. The COR Programs purview includes the majority of the field known as astronomy, from antiquity to the present.

The weak force and SETH: The search for Extra-Terrestrial Homochirality

International Nuclear Information System (INIS)

MacDermott, A.J.

1996-01-01

We propose that a search for extra-terrestrial life can be approached as a Search for Extra-Terrestrial Homochirality emdash SETH. Homochirality is probably a pre-condition for life, so a chiral influence may be required to get life started. We explain how the weak force mediated by the Z 0 boson gives rise to a small parity-violating energy difference (PVED) between enantiomers, and discuss how the resulting small excess of the more stable enantiomer may be amplified to homochirality. Titan and comets are good places to test for emerging pre-biotic homochirality, while on Mars there may be traces of homochirality as a relic of extinct life. Our calculations of the PVED show that the natural L-amino acids are indeed more stable than their enantiomers, as are several key D-sugars and right-hand helical DNA. Thiosubstituted DNA analogues show particularly large PVEDs. L-quartz is also more stable than D-quartz, and we believe that further crystal counts should be carried out to establish whether reported excesses of L quartz are real. Finding extra-terrestrial molecules of the same hand as on Earth would lend support to the universal chiral influence of the weak force. We describe a novel miniaturized space polarimeter, called the SETH Cigar, which we hope to use to detect optical rotation on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. Even if we do not find the same hand as on Earth, finding extra-terrestrial optical rotation would be of enormous importance as it would still be the homochiral signature of life. copyright 1996 American Institute of Physics

Cosmic strings and galaxy formation

International Nuclear Information System (INIS)

Bertschinger, E.

1989-01-01

Cosmic strings have become increasingly popular candidates as seeds for the formation of structure in the universe. This scenario, remains a serious cosmogonical model despite close scrutiny. In constrast, magnetic monopoles and domain walls - relic topological defects as are cosmic strings - are disastrous for cosmology if they are left over from the early universe. The production of heavy cosmic strings is speculative, as it depends on the details of ultrahigh energy physics. Fortunately, speculation about cosmic strings is not entirely idle because, if they exist and are heavy enough to seed galaxy formation, cosmic strings can be detected astronomically. Failure to detect cosmic strings would impose some constraints on grand unified theories (GUTs); their discovery would have exciting consequences for high energy physics and cosmology. This article reviews the basic physics of nonsuperconducting cosmic strings, highlighting the field theory aspects, and provides a progress report on calculations of structure formation with cosmic strings

The study of light phenomena in the planetary atmosphere and the properties of water as a scintillator under the action of cosmic rays

International Nuclear Information System (INIS)

Caramete, Laurentiu-Ioan; Stere, Oana; Haiduc, Maria; Rusu, Mircea Victor

2004-01-01

Few scientific fields are so attractive and have an interdisciplinary nature like nuclear astrophysics. It covers the study of the synthesis of the elements and the evolution of cosmic sites where such synthesis takes place. The systems like early universe, interstellar medium, giant red stars, supernovae and the birth of new stars are considerable problems and modern science research themes. Huge amount of data is gathered daily, by astronomical observatories, satellites and orbital stations which have more and more complex equipment. For explaining and understanding these data, theories and very complex computerized models are used. Our proposed installation will be used for obtaining a large variety of data, parameters and values of some dimensions which make part of theoretical and simulation models for observed processes in astrophysics and astronomy. We will study the scintillation phenomena from atmosphere with applications in the study of cosmic rays, applications regarding some aspects of flash or sparking observed in the high altitude of terrestrial atmosphere and which are due to small drops of water or ice. On the other side, cosmic radiation causes a continuous bombardment of high atmosphere and such phenomena could be produced if the drops of water, in special conditions, are the place for scintillation. The fundamental interest is that a simple inorganic system, like water, could provide scintillation in pure conditions, in contamination conditions or in solid state. For this purpose we will study the following items: the possible energy levels in the water molecule in different conditions and the way in which the position of levels are changed in solution, the influence of different impurities in water, which form (in contact with water molecules) structures and different molecular groups in water which can have energy levels able to act like scintillation centers. Our purposes are the following: - making new scintillators, cheaper and more

Terrestrial Permafrost Models of Martian Habitats and Inhabitants

Science.gov (United States)

Gilichinsky, D.

2011-12-01

The terrestrial permafrost is the only rich depository of viable ancient microorganisms on Earth, and can be used as a bridge to possible Martian life forms and shallow subsurface habitats where the probability of finding life is highest. Since there is a place for water, the requisite condition for life, the analogous models are more or less realistic. If life ever existed on Mars, traces might have been preserved and could be found at depth within permafrost. The age of the terrestrial isolates corresponds to the longevity of the frozen state of the embedding strata, with the oldest known dating back to the late Pliocene in Arctic and late Miocene in Antarctica. Permafrost on Earth and Mars vary in age, from a few million years on Earth to a few billion years on Mars. Such a difference in time scale would have a significant impact on the possibility of preserving life on Mars, which is why the longevity of life forms preserved within terrestrial permafrost can only be an approximate model for Mars. 1. A number of studies indicate that the Antarctic cryosphere began to develop on the Eocene-Oligocene boundary, after the isolation of the continent. Permafrost degradation is only possible if mean annual ground temperature, -28°C now, rise above freezing, i.e., a significant warming to above 25°C is required. There is no evidence of such sharp temperature increase, which indicates that the climate and geological history was favorable to persistence of pre-Pliocene permafrost. These oldest relics (~30Myr) are possibly to be found at high hypsometric levels of ice-free areas (Dry Valleys and nearby mountains). It is desirable to test the layers for the presence of viable cells. The limiting age, if one exists, within this ancient permafrost, where the viable organisms were no longer present, could be established as the limit for life preservation below 0oC. Positive results will extend the known temporal limits of life in permafrost. 2. Even in this case, the age of

Origins fourteen billion years of cosmic evolution

CERN Document Server

Tyson, Neil deGrasse

2004-01-01

Origins explores cosmic science's stunning new insights into the formation and evolution of our universe--of the cosmos, of galaxies and galaxy clusters, of stars within galaxies, of planets that orbit those stars, and of different forms of life that take us back to the first three seconds and forward through three billion years of life on Earth to today's search for life on other planets. Drawing on the current cross-pollination of geology, biology and astrophysics, Origins explains the thrilling daily breakthroughs in our knowledge of the universe from dark energy to life on Mars to the mysteries of space and time. Distilling complex science in clear and lively prose, co-authors Neil deGrasse Tyson and Donald Goldsmith conduct a galvanising tour of the cosmos revealing what the universe has been up to while turning part of itself into us.

Calculation of cosmic ray induced single event upsets: Program CRUP (Cosmic Ray Upset Program)

Science.gov (United States)

Shapiro, P.

1983-09-01

This report documents PROGRAM CRUP, COSMIC RAY UPSET PROGRAM. The computer program calculates cosmic ray induced single-event error rates in microelectronic circuits exposed to several representative cosmic-ray environments.

Harlow Shapley's Biological Universe: Cosmic Evolution and its Uses

Science.gov (United States)

Palmeri, J.

2002-12-01

Harlow Shapley was an astronomer with a lifelong interest in biological questions. An early fascination with ants acquired at Mount Wilson became a continuing avocation. During his years in California, Shapley made frequent trips to La Jolla biological station and interacted with prominent biologists. At Harvard in the 1920s Shapley initiated a series of interdisciplinary seminars, one of which was on "The Origin of Life." At this time he also displayed an interest in the question of life in the universe. In response to an inquiry from Charles Abbot of the Smithsonian, Shapley identified "life in the universe" as one of the most important scientific questions of the day. Shapley's continuing interest in these questions found expression in his many popularizations - articles, books, lectures, and other media. (A decade before Sagan's memorable appearances on the Johnny Carson show, Shapley was engaging in his own dialogue with the American public on life in the universe, through Tonight Show host Jack Paar). Evolution was the idea that underlay Shapley's discussions of these biological themes and the vehicle through which he popularized science as well as his own vision of the wider significance of science for humanity. As an astronomer with a profound interest in biological subjects, Shapley was uniquely positioned to popularize cosmic evolution, and to use this theme to promote his belief that science could serve as a kind of "stellar theology." Shapley's case illustrates how cosmic evolution, like biological evolution, has served as more than a scientific account of nature; it has become an idea invested with moral and cultural significance. Shapley's promotion of cosmic evolution throughout the 1950s and 1960s can be understood against the backdrop of developments in the sciences as well as the historical and personal factors that shaped his career as a spokesman for science. This research was supported by grants from the American Institute of Physics and the

Cosmic ray diffusion: report of the workshop in cosmic ray diffusion theory

International Nuclear Information System (INIS)

Birmingham, T.J.; Jones, F.C.

1975-02-01

A workshop in cosmic ray diffusion theory was held at Goddard Space Flight Center on May 16-17, 1974. Topics discussed and summarized are: (1) cosmic ray measurements as related to diffusion theory; (2) quasi-linear theory, nonlinear theory, and computer simulation of cosmic ray pitch-angle diffusion; and (3) magnetic field fluctuation measurements as related to diffusion theory. (auth)

11. European cosmic ray symposium

International Nuclear Information System (INIS)

1989-03-01

The biannual Symposium includes all aspects of cosmic ray research. The scientific programme was organized under three main headings: Cosmic rays in the heliosphere, Cosmic rays in the interstellar and extragalactic space, Properties of high-energy interactions as studied by cosmic rays. Seven invited talks were indexed seprately for the INIS database. (R.P.)

A COSMIC VARIANCE COOKBOOK

International Nuclear Information System (INIS)

Moster, Benjamin P.; Rix, Hans-Walter; Somerville, Rachel S.; Newman, Jeffrey A.

2011-01-01

Deep pencil beam surveys ( 2 ) are of fundamental importance for studying the high-redshift universe. However, inferences about galaxy population properties (e.g., the abundance of objects) are in practice limited by 'cosmic variance'. This is the uncertainty in observational estimates of the number density of galaxies arising from the underlying large-scale density fluctuations. This source of uncertainty can be significant, especially for surveys which cover only small areas and for massive high-redshift galaxies. Cosmic variance for a given galaxy population can be determined using predictions from cold dark matter theory and the galaxy bias. In this paper, we provide tools for experiment design and interpretation. For a given survey geometry, we present the cosmic variance of dark matter as a function of mean redshift z-bar and redshift bin size Δz. Using a halo occupation model to predict galaxy clustering, we derive the galaxy bias as a function of mean redshift for galaxy samples of a given stellar mass range. In the linear regime, the cosmic variance of these galaxy samples is the product of the galaxy bias and the dark matter cosmic variance. We present a simple recipe using a fitting function to compute cosmic variance as a function of the angular dimensions of the field, z-bar , Δz, and stellar mass m * . We also provide tabulated values and a software tool. The accuracy of the resulting cosmic variance estimates (δσ v /σ v ) is shown to be better than 20%. We find that for GOODS at z-bar =2 and with Δz = 0.5, the relative cosmic variance of galaxies with m * >10 11 M sun is ∼38%, while it is ∼27% for GEMS and ∼12% for COSMOS. For galaxies of m * ∼ 10 10 M sun , the relative cosmic variance is ∼19% for GOODS, ∼13% for GEMS, and ∼6% for COSMOS. This implies that cosmic variance is a significant source of uncertainty at z-bar =2 for small fields and massive galaxies, while for larger fields and intermediate mass galaxies, cosmic

The conceptual design of a hybrid life support system based on the evaluation and comparison of terrestrial testbeds

Science.gov (United States)

Czupalla, M.; Horneck, G.; Blome, H. J.

This report summarizes a trade study of different options of a bioregenerative Life Support System (LSS) and a subsequent conceptual design of a hybrid LSS. The evaluation was based mainly on the terrestrial testbed projects MELISSA (ESA) and BIOS (Russia). In addition, some methods suggested by the Advanced Life Support Project (NASA) were considered. Computer models, including mass flows were established for each of the systems with the goal of closing system loops to the extent possible. In order to cope with the differences in the supported crew size and provided nutrition, all systems were scaled for supporting a crew of six for a 780 day Mars mission (180 days transport to Mars; 600 days surface period) as given in the NASA Design Reference Mission Scenario [Hoffman, S.J., Kaplan, D.L. Human exploration of Mars: the Reference Mission of the NASA Mars Exploratory Study, 1997]. All models were scaled to provide the same daily allowances, as of calories, to the crew. Equivalent System Mass (ESM) analysis was used to compare the investigated system models against each other. Following the comparison of the terrestrial systems, the system specific subsystem options for Food Supply, Solid Waste Processing, Water Management and Atmosphere Revitalization were evaluated in a separate trade study. The best subsystem technologies from the trade study were integrated into an overall design solution based on mass flow relationships. The optimized LSS is mainly a bioregenerative system, complemented by a few physico-chemical elements, with a total ESM of 18,088 kg, which is about 4 times higher than that of a pure physico-chemical LSS, as designed in an earlier study.

Cosmic Accelerators: An Introduction

International Nuclear Information System (INIS)

Kanbach, Gottfried

2005-01-01

High energy, relativistic, particles are an essential component of the Universe and play a major role in astrophysics. In a few years we will reach the centennial of the discovery of cosmic rays; all through this century the properties, origin, and effects of this radiation have intrigued researchers in astrophysics and elementary particles alike. We briefly review the history, current status, and future perspectives of cosmic ray research. Emphasis will be placed on the multitude of cosmic accelerators, direct observations of these objects, and the effects of cosmic rays in the Galaxy and beyond

High energy cosmic rays

CERN Document Server

Stanev, Todor

2010-01-01

Offers an accessible text and reference (a cosmic-ray manual) for graduate students entering the field and high-energy astrophysicists will find this an accessible cosmic-ray manual Easy to read for the general astronomer, the first part describes the standard model of cosmic rays based on our understanding of modern particle physics. Presents the acceleration scenario in some detail in supernovae explosions as well as in the passage of cosmic rays through the Galaxy. Compares experimental data in the atmosphere as well as underground are compared with theoretical models

High Energy Cosmic Electrons: Messengers from Nearby Cosmic Ray Sources or Dark Matter?

Science.gov (United States)

Moiseev, Alexander

2011-01-01

This slide presentation reviews the recent discoveries by the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM) on board the Fermi Gamma-Ray Telescope in reference to high energy cosmic electrons, and whether their source is cosmic rays or dark matter. Specific interest is devoted to Cosmic Ray electrons anisotropy,

Cosmic strings

International Nuclear Information System (INIS)

Bennett, D.P.

1988-07-01

Cosmic strings are linear topological defects that are predicted by some grand unified theories to form during a spontaneous symmetry breaking phase transition in the early universe. They are the basis for the only theories of galaxy formation aside from quantum fluctuations from inflation that are based on fundamental physics. In contrast to inflation, they can also be observed directly through gravitational lensing and their characteristic microwave background anistropy. It has recently been discovered by F. Bouchet and myself that details of cosmic string evolution are very different from the so-called ''standard model'' that has been assumed in most of the string induced galaxy formation calculations. Therefore, the details of galaxy formation in the cosmic string models are currently very uncertain. 29 refs., 9 figs

Cosmic-Ray Extremely Distributed Observatory: a global cosmic ray detection framework

Science.gov (United States)

Sushchov, O.; Homola, P.; Dhital, N.; Bratek, Ł.; Poznański, P.; Wibig, T.; Zamora-Saa, J.; Almeida Cheminant, K.; Alvarez Castillo, D.; Góra, D.; Jagoda, P.; Jałocha, J.; Jarvis, J. F.; Kasztelan, M.; Kopański, K.; Krupiński, M.; Michałek, M.; Nazari, V.; Smelcerz, K.; Smolek, K.; Stasielak, J.; Sułek, M.

2017-12-01

The main objective of the Cosmic-Ray Extremely Distributed Observatory (CREDO) is the detection and analysis of extended cosmic ray phenomena, so-called super-preshowers (SPS), using existing as well as new infrastructure (cosmic-ray observatories, educational detectors, single detectors etc.). The search for ensembles of cosmic ray events initiated by SPS is yet an untouched ground, in contrast to the current state-of-the-art analysis, which is focused on the detection of single cosmic ray events. Theoretical explanation of SPS could be given either within classical (e.g., photon-photon interaction) or exotic (e.g., Super Heavy Dark Matter decay or annihilation) scenarios, thus detection of SPS would provide a better understanding of particle physics, high energy astrophysics and cosmology. The ensembles of cosmic rays can be classified based on the spatial and temporal extent of particles constituting the ensemble. Some classes of SPS are predicted to have huge spatial distribution, a unique signature detectable only with a facility of the global size. Since development and commissioning of a completely new facility with such requirements is economically unwarranted and time-consuming, the global analysis goals are achievable when all types of existing detectors are merged into a worldwide network. The idea to use the instruments in operation is based on a novel trigger algorithm: in parallel to looking for neighbour surface detectors receiving the signal simultaneously, one should also look for spatially isolated stations clustered in a small time window. On the other hand, CREDO strategy is also aimed at an active engagement of a large number of participants, who will contribute to the project by using common electronic devices (e.g., smartphones), capable of detecting cosmic rays. It will help not only in expanding the geographical spread of CREDO, but also in managing a large manpower necessary for a more efficient crowd-sourced pattern recognition scheme to

Comparative analyses of olfactory systems in terrestrial crabs (Brachyura: evidence for aerial olfaction?

Directory of Open Access Journals (Sweden)

Jakob Krieger

2015-12-01

Full Text Available Adaptations to a terrestrial lifestyle occurred convergently multiple times during the evolution of the arthropods. This holds also true for the “true crabs” (Brachyura, a taxon that includes several lineages that invaded land independently. During an evolutionary transition from sea to land, animals have to develop a variety of physiological and anatomical adaptations to a terrestrial life style related to respiration, reproduction, development, circulation, ion and water balance. In addition, sensory systems that function in air instead of in water are essential for an animal’s life on land. Besides vision and mechanosensory systems, on land, the chemical senses have to be modified substantially in comparison to their function in water. Among arthropods, insects are the most successful ones to evolve aerial olfaction. Various aspects of terrestrial adaptation have also been analyzed in those crustacean lineages that evolved terrestrial representatives including the taxa Anomala, Brachyura, Amphipoda, and Isopoda. We are interested in how the chemical senses of terrestrial crustaceans are modified to function in air. Therefore, in this study, we analyzed the brains and more specifically the structure of the olfactory system of representatives of brachyuran crabs that display different degrees of terrestriality, from exclusively marine to mainly terrestrial. The methods we used included immunohistochemistry, detection of autofluorescence- and confocal microscopy, as well as three-dimensional reconstruction and morphometry. Our comparative approach shows that both the peripheral and central olfactory pathways are reduced in terrestrial members in comparison to their marine relatives, suggesting a limited function of their olfactory system on land. We conclude that for arthropod lineages that invaded land, evolving aerial olfaction is no trivial task.

Super-long Anabiosis of Ancient Microorganisms in Ice and Terrestrial Models for Development of Methods to Search for Life on Mars, Europa and other Planetary Bodies

Science.gov (United States)

Abyzov, S. S.; Duxbury, N. S.; Bobin, N. E.; Fukuchi, M.; Hoover, R. B.; Kanda, H.; Mitskevich, I. N.; Mulyukin, A. L.; Naganuma, T.; Poglazova, M. N.;

Cosmic ray: Studying the origin

International Nuclear Information System (INIS)

Szabelski, J.

1997-01-01

Investigations of the origin of cosmic rays are presented. Different methods are discussed: studies of cosmic gamma rays of energy from 30 MeV to about 10 15 eV (since photons point to their places of origin), studies of the mass composition of cosmic rays (because it reflects source morphology), and studies of cosmic rays with energy above 1O 19 eV (for these are the highest energies observed in nature). (author)

Constraints on cosmic strings due to black holes formed from collapsed cosmic string loops

International Nuclear Information System (INIS)

Caldwell, R.R.; Gates, E.

1993-05-01

The cosmological features of primordial black holes formed from collapsed cosmic string loops are studied. Observational restrictions on a population of primordial black holes are used to restrict f, the fraction of cosmic string loops which collapse to form black holes, and μ, the cosmic string mass-per-unit-length. Using a realistic model of cosmic strings, we find the strongest restriction on the parameters f and μ is due to the energy density in 100MeV photons radiated by the black holes. We also find that inert black hole remnants cannot serve as the dark matter. If earlier, crude estimates of f are reliable, our results severely restrict μ, and therefore limit the viability of the cosmic string large-scale structure scenario

Galactic cosmic rays and tropical ozone asymmetries

International Nuclear Information System (INIS)

Kilifarska, Natalya; Bakhmutov, Volodymyr; Melnyk, Galyna

2017-01-01

Lower stratospheric ozone O_3 is of special interest to climatic studies due to its direct influence on the tropopause temperature, and correspondingly on Earth’s radiation balance. By reason of the suppressed dissociation of molecular oxygen by solar UV radiation and the long life span of the lower stratospheric O_3 , its temporal variability is usually attributed to atmospheric circulation. Here we report about latitudinal-longitudinal differences in a centennial evolution of the tropical O_3 at 70 hPa. These asymmetries are hardly explicable within the concept of the ozone’s dynamical control alone. Analysis of ozone, energetic particles and the geomagnetic records from the last 111 years has revealed that they all evolve synchronously with time. This coherence motivates us to propose a mechanism explaining the geomagnetic and galactic cosmic ray influence on the near tropopause O_3 , allowing for an understanding of its spatial-temporal variability during the past century. Key words: galactic cosmic rays, asymmetries of tropical ozone distribution, geomagnetic filed

D-term inflation, cosmic strings, and consistency with cosmic microwave background measurements.

Science.gov (United States)

Rocher, Jonathan; Sakellariadou, Mairi

2005-01-14

Standard D-term inflation is studied in the framework of supergravity. D-term inflation produces cosmic strings; however, it can still be compatible with cosmic microwave background (CMB) measurements without invoking any new physics. The cosmic strings contribution to the CMB data is not constant, nor dominant, contrary to some previous results. Using current CMB measurements, the free parameters (gauge and superpotential couplings, as well as the Fayet-Iliopoulos term) of D-term inflation are constrained.

Cosmic ray modulation

International Nuclear Information System (INIS)

Ueno, Hirosachi

1974-01-01

It is important to know the physical state of solar plasma region by the observation of intensity variation of cosmic ray which passed through the solar plasma region, because earth magnetosphere is formed by the interaction between geomagnetic field and solar plasma flow. The observation of cosmic ray intensity is useful to know the average condition of the space of 0.1--3 A.U., and gives the structure of the magnetic field in solar wind affecting the earth magnetosphere. The observation of neutron component in cosmic ray has been carried out at Norikura, Tokyo, Fukushima and Morioka. The lower limit of the energy of incident cosmic ray which can be observed at each station is different, and the fine structure of the variation can be known by comparison. The intensity of meson component in cosmic ray has been measured in underground, and the state of solar plasma region 2--3 A.U. from the earth can be known. The underground measurement has been made at Takeyama and Matsumoto, and a new station at Sakashita is proposed. The measurement at Sakashita will be made by proportional counters at the depth of 100m (water equivalent). Arrangement of detectors is shown. (Kato, T.)

Cosmic Humanity: Utopia, Realities, Prospects

OpenAIRE

Sergey Krichevsky

2017-01-01

The philosophical foundations of the theory and practice of the creation of cosmic humanity as a process of the evolution of human civilization, the emergence into space, with the prospect of resettlement outside the Earth are considered. There is a connection between myths, fantasies, ideas, concepts and projects aimed at the exploration of outer space, the creation of cosmic humanity. A new and voluminous definition of cosmic humanity in the evolutionary paradigm is given. Cosmic humanity i...

Cosmic-ray-veto detector system

International Nuclear Information System (INIS)

Miller, D.W.; Menlove, H.O.

1992-12-01

To reduce the cosmic-ray-induced neutron background, we are testing a cosmic-ray veto option with a neutron detector system that uses plastic scintillator slabs mounted on the outside of a 3 He-tube detector. The scintillator slabs eliminate unwanted cosmic-ray events, enabling the detector to assay low-level plutonium samples, for which a low-background coincident signature is critical. This report describes the design and testing of the prototype cosmic-ray-veto detector system

Terrestrial microorganisms at an altitude of 20,000 m in Earth's atmosphere

Science.gov (United States)

Griffin, Dale W.

2004-01-01

A joint effort between the U.S. Geological Survey's (USGS) Global Desert Dust and NASA's Stratospheric and Cosmic Dust Programs identified culturable microbes from an air sample collected at an altitude of 20,000 m. A total of 4 fungal (Penicillium sp.) and 71 bacteria colonyforming units (70 colonies of Bacillus luciferensis believed to have originated from a single cell collected at altitude and one colony of Bacillus sphaericus) were enumerated, isolated and identified using a morphological key and 16S rDNA sequencing respectively. All of the isolates identified were sporeforming pigmented fungi or bacteria of terrestrial origin and demonstrate that the presence of viable microorganisms in Earth's upper atmosphere may not be uncommon.

Test particle trajectories near cosmic strings

Indian Academy of Sciences (India)

We present a detailed analysis of the motion of test particle in the gravitational field of cosmic strings in different situations using the Hamilton–Jacobi (H–J) formalism. We have discussed the trajectories near static cosmic string, cosmic string in Brans–Dicke theory and cosmic string in dilaton gravity.

Cosmic ray: Studying the origin

Energy Technology Data Exchange (ETDEWEB)

Szabelski, J. [Cosmic Ray Laboratory, Soltan Institute for Nuclear Studies, Lodz (Poland)

1997-12-31

Investigations of the origin of cosmic rays are presented. Different methods are discussed: studies of cosmic gamma rays of energy from 30 MeV to about 10{sup 15} eV (since photons point to their places of origin), studies of the mass composition of cosmic rays (because it reflects source morphology), and studies of cosmic rays with energy above 1O{sup 19} eV (for these are the highest energies observed in nature). (author) 101 refs, 19 figs, 7 tabs

Department of Cosmic Radiation Physics: Overview

International Nuclear Information System (INIS)

Gawin, J.

1999-01-01

Full text: The Department of Cosmic Ray Physics in Lodz is involved in basic research in the area of high energy physics and cosmic ray physics related to: - Studies of asymptotic properties of hadronic interactions based on the analysis of cosmic ray propagation in the atmosphere. - Experimental and phenomenological studies of Extensive Air Showers induced by cosmic ray particles. - Search for point sources of high energy cosmic rays. - Studies of cosmic ray propagation in the Galaxy and mechanisms of particle acceleration. - Studies of mass composition of cosmic rays in the energy range 10 15 - 10 17 eV. Theoretical and experimental studies of Extensive Air Shower properties are performed mostly based on the results obtained by the Lodz Extensive Air Shower Array. We analysed nearly 100,000 events of energies above 10 15 eV registered by the Lodz hodoscope. We have developed the method of data analysis which allows us to verify different models of cosmic ray mass composition. In our research in high energy cosmic rays we also used experimental data from other collaborating experiments in Karlsruhe, Baksan and THEMISTOCLE. The Lodz group collaborates with many foreign institutes and laboratories in construction and data interpretation of cosmic ray experiments. Our most important partners are: Forschungszentrum in Karlsruhe (Germany), College de France, Institute for Nuclear Studies of the Russian Academy of Science, University of Perpignan and Uppsala University (Sweden). (author)

Department of Cosmic Radiation Physics - Overview

International Nuclear Information System (INIS)

Gawin, J.

1997-01-01

Full text: The Department of Cosmic Ray Physics in Lodz is involved in basic research in the area of high energy physics and cosmic ray physics related to: -Studies of the asymptotic properties of hadronic interactions from the analysis of cosmic ray propagation in the atmosphere. -Studies of structure and properties of Extensive Air Showers induced by cosmic ray particles. -Search for point sources of high energy cosmic rays. -Studies of cosmic ray propagation in the Galaxy and mechanisms of particle acceleration. -Studies of the mass composition of cosmic rays in the energy range 10 15 -10 17 eV. Theoretical and experimental studies of nuclear interactions for energies exceeding those obtained by modern particle accelerators are performed employing results obtained by the Lodz Extensive Air Shower Array. The Lodz hodoscope can register electromagnetic components of cosmic ray showers in the atmosphere as well as muons at two energy thresholds. Data collected by the Lodz array are also used to study mass composition of cosmic rays in the energy range 10 15 - 10 17 eV. The Lodz group collaborates with foreign institutes and laboratories on construction and data interpretation of cosmic ray experiments. Our most important partners are: Forschungszentrum Karlsruhe (Germany), College de France, the Institute for Nuclear Studies of the Russian Academy of Sciences, the University of Durham, and the University of Perpignan. (author)

Deepening Cosmic Education

Science.gov (United States)

Leonard, Gerard

2013-01-01

This article is a special blend of research, theory, and practice, with clear insight into the origins of Cosmic Education and cosmic task, while recalling memories of student explorations in botany, in particular, episodes from Mr. Leonard's teaching. Mr. Leonard speaks of a storytelling curriculum that eloquently puts perspective into dimensions…

Department of Cosmic Radiation Physics: Overview

International Nuclear Information System (INIS)

Szabelski, J.

2000-01-01

Full text: Department of Cosmic Ray Physics in Lodz is involved in basic research in the area of high-energy physics and cosmic ray physics related to: -Studies of asymptotic properties of hadronic interactions based on the analysis of cosmic ray propagation through the atmosphere. -Experimental and phenomenological studies of Extensive Air Showers induced by cosmic ray particles. - Search for high-energy cosmic ray point sources. - Studies of cosmic ray propagation in the Galaxy and particle acceleration mechanisms. -Studies of mass composition of cosmic rays in the energy range 10 15 -10 17 eV. Theoretical and experimental studies of Extensive Air Shower properties are performed mainly on the basis of the results obtained by the Lodz Extensive Air Shower Array. We have analysed nearly 100,000 events of energies above 10 15 eV registered in the Lodz hodoscope. We have developed a method to verify different models of cosmic ray mass composition. The Lodz group collaborates with many foreign institutes and laboratories in construction and data interpretation of cosmic ray experiments. Our most important partners are: Forschungszentrum in Karlsruhe (Germany), College de France, Institute for Nuclear Studies of the Russian Academy of Sciences and Uppsala University (Sweden). (author)

Robust constraint on cosmic textures from the cosmic microwave background.

Science.gov (United States)

Feeney, Stephen M; Johnson, Matthew C; Mortlock, Daniel J; Peiris, Hiranya V

2012-06-15

Fluctuations in the cosmic microwave background (CMB) contain information which has been pivotal in establishing the current cosmological model. These data can also be used to test well-motivated additions to this model, such as cosmic textures. Textures are a type of topological defect that can be produced during a cosmological phase transition in the early Universe, and which leave characteristic hot and cold spots in the CMB. We apply bayesian methods to carry out a rigorous test of the texture hypothesis, using full-sky data from the Wilkinson Microwave Anisotropy Probe. We conclude that current data do not warrant augmenting the standard cosmological model with textures. We rule out at 95% confidence models that predict more than 6 detectable cosmic textures on the full sky.

Department of Cosmic Radiation Physics: Overview

International Nuclear Information System (INIS)

Gawin, J.

1998-01-01

(full text) The Department of Cosmic Ray Physics in Lodz is involved in basic research in the area of high energy physics and cosmic ray physics related to: -Studies of asymptotic properties of hadronic interactions based on the analysis of cosmic ray propagation in the atmosphere. -Studies of the structure and properties of Extensive Air Showers induced by cosmic ray particles. - Search for point sources of high energy cosmic rays. - Studies of cosmic ray propagation in the Galaxy and mechanisms of particle acceleration. - Studies of mass composition of cosmic rays in the energy range l0 15 -10 17 eV. Theoretical and experimental studies of nuclear interactions for energies exceeding those obtained by modern particle accelerators are performed based on the results obtained by the Lodz Extensive Air Shower Array. The Lodz hodoscope can register the electromagnetic component of cosmic ray showers developing in the atmosphere as well as muons of two energy thresholds. Data collected by the Lodz array are also used to study the mass composition of cosmic rays in the energy range 10 15 -10 17 eV. The Lodz group collaborates with many foreign institutes and laboratories in construction and data interpretation of cosmic ray experiments. Our most important partners are: Forschungszentrum Karlsruhe (Germany), College de' France, the Institute for Nuclear Studies of the Russian Academy of Science, the University of Perpignan (France) and Uppsala University (Sweden). (author)

Polyphenism in social insects: insights from a transcriptome-wide analysis of gene expression in the life stages of the key pollinator, Bombus terrestris

Directory of Open Access Journals (Sweden)

Colgan Thomas J

2011-12-01

Full Text Available Abstract Background Understanding polyphenism, the ability of a single genome to express multiple morphologically and behaviourally distinct phenotypes, is an important goal for evolutionary and developmental biology. Polyphenism has been key to the evolution of the Hymenoptera, and particularly the social Hymenoptera where the genome of a single species regulates distinct larval stages, sexual dimorphism and physical castes within the female sex. Transcriptomic analyses of social Hymenoptera will therefore provide unique insights into how changes in gene expression underlie such complexity. Here we describe gene expression in individual specimens of the pre-adult stages, sexes and castes of the key pollinator, the buff-tailed bumblebee Bombus terrestris. Results cDNA was prepared from mRNA from five life cycle stages (one larva, one pupa, one male, one gyne and two workers and a total of 1,610,742 expressed sequence tags (ESTs were generated using Roche 454 technology, substantially increasing the sequence data available for this important species. Overlapping ESTs were assembled into 36,354 B. terrestris putative transcripts, and functionally annotated. A preliminary assessment of differences in gene expression across non-replicated specimens from the pre-adult stages, castes and sexes was performed using R-STAT analysis. Individual samples from the life cycle stages of the bumblebee differed in the expression of a wide array of genes, including genes involved in amino acid storage, metabolism, immunity and olfaction. Conclusions Detailed analyses of immune and olfaction gene expression across phenotypes demonstrated how transcriptomic analyses can inform our understanding of processes central to the biology of B. terrestris and the social Hymenoptera in general. For example, examination of immunity-related genes identified high conservation of important immunity pathway components across individual specimens from the life cycle stages while

Polyphenism in social insects: Insights from a transcriptome-wide analysis of gene expression in the life stages of the key pollinator, Bombus terrestris

LENUS (Irish Health Repository)

Colgan, Thomas J

2011-12-20

Abstract Background Understanding polyphenism, the ability of a single genome to express multiple morphologically and behaviourally distinct phenotypes, is an important goal for evolutionary and developmental biology. Polyphenism has been key to the evolution of the Hymenoptera, and particularly the social Hymenoptera where the genome of a single species regulates distinct larval stages, sexual dimorphism and physical castes within the female sex. Transcriptomic analyses of social Hymenoptera will therefore provide unique insights into how changes in gene expression underlie such complexity. Here we describe gene expression in individual specimens of the pre-adult stages, sexes and castes of the key pollinator, the buff-tailed bumblebee Bombus terrestris. Results cDNA was prepared from mRNA from five life cycle stages (one larva, one pupa, one male, one gyne and two workers) and a total of 1,610,742 expressed sequence tags (ESTs) were generated using Roche 454 technology, substantially increasing the sequence data available for this important species. Overlapping ESTs were assembled into 36,354 B. terrestris putative transcripts, and functionally annotated. A preliminary assessment of differences in gene expression across non-replicated specimens from the pre-adult stages, castes and sexes was performed using R-STAT analysis. Individual samples from the life cycle stages of the bumblebee differed in the expression of a wide array of genes, including genes involved in amino acid storage, metabolism, immunity and olfaction. Conclusions Detailed analyses of immune and olfaction gene expression across phenotypes demonstrated how transcriptomic analyses can inform our understanding of processes central to the biology of B. terrestris and the social Hymenoptera in general. For example, examination of immunity-related genes identified high conservation of important immunity pathway components across individual specimens from the life cycle stages while olfactory

Seasonal variation in the environmental background level of cosmic ray produced 22Na

International Nuclear Information System (INIS)

Tokuyama, Hideki; Igarashi, Shuichi

1998-01-01

22 Na (half life 2.6 year) is produced by cosmic rays, nuclear test and reactor. 7 Be (half life 53.3 day) is produced in atmosphere by reaction. 7 Be/ 22 Na activity ratio is good factor to observe the mixing process between stratosphere and troposphere atmosphere. The seasonal variation of 7 Be and 22 Na deposition, the ratio and the background level of 22 Na deposition were observed in Fukui city and reported in this paper. Very large reasonable change of 22 Na deposition was observed, especially the largest peak in winter. Because the concentration of cosmic-ray-produced nuclear in precipitation and the amount of precipitation were large in winter. 22 Na produced by the previous nuclear test was attenuated. The present 22 Na is only produced by cosmic rays, indicating the background level. 22 Na deposition at Fukui was 0.42Bq m -2 y -1 , one ten-thousandth of 7 Be deposition. 7 Be/ 22 Na activity ratio was changed in season and the largest peak was shown in autumn. In this reason, atmosphere showed relatively short residence time in the lower part of stratosphere, Mixture and exchange of atmosphere between stratosphere and troposphere were the most active in autumn. (S.Y.)

Cosmic Ether

CERN Document Server

Tomaschitz, R

1998-01-01

A prerelativistic approach to particle dynamics is explored in an expanding Robertson-Walker cosmology. The receding galactic background provides a distinguished frame of reference and a unique cosmic time. In this context the relativistic, purely geometric space-time concept is criticized. Physical space is regarded as a permeable medium, the cosmic ether, which effects the world-lines of particles and rays. We study in detail a Robertson-Walker universe with linear expansion factor and negatively curved, open three-space; we choose the permeability tensor of the ether in such a way that the semiclassical approximation is exact. Galactic red-shifts depend on the refractive index of the ether. In the local Minkowskian limit the ether causes a time variation of mass, which scales inversely proportional to cosmic time. In the globally geodesic rest frames of galactic observers the ether manifests itself in an unbounded speed of signal transfer, in bifurcations of world-lines, and in time inversion effects.

Cosmic vacuum

International Nuclear Information System (INIS)

Chernin, Artur D

2001-01-01

Recent observational studies of distant supernovae have suggested the existence of cosmic vacuum whose energy density exceeds the total density of all the other energy components in the Universe. The vacuum produces the field of antigravity that causes the cosmological expansion to accelerate. It is this accelerated expansion that has been discovered in the observations. The discovery of cosmic vacuum radically changes our current understanding of the present state of the Universe. It also poses new challenges to both cosmology and fundamental physics. Why is the density of vacuum what it is? Why do the densities of the cosmic energy components differ in exact value but agree in order of magnitude? On the other hand, the discovery made at large cosmological distances of hundreds and thousands Mpc provides new insights into the dynamics of the nearby Universe, the motions of galaxies in the local volume of 10 - 20 Mpc where the cosmological expansion was originally discovered. (reviews of topical problems)

Cosmic vacuum

Energy Technology Data Exchange (ETDEWEB)

Chernin, Artur D [P.K. Shternberg State Astronomical Institute at the M.V. Lomonosov Moscow State University, Moscow (Russian Federation)

2001-11-30

Recent observational studies of distant supernovae have suggested the existence of cosmic vacuum whose energy density exceeds the total density of all the other energy components in the Universe. The vacuum produces the field of antigravity that causes the cosmological expansion to accelerate. It is this accelerated expansion that has been discovered in the observations. The discovery of cosmic vacuum radically changes our current understanding of the present state of the Universe. It also poses new challenges to both cosmology and fundamental physics. Why is the density of vacuum what it is? Why do the densities of the cosmic energy components differ in exact value but agree in order of magnitude? On the other hand, the discovery made at large cosmological distances of hundreds and thousands Mpc provides new insights into the dynamics of the nearby Universe, the motions of galaxies in the local volume of 10 - 20 Mpc where the cosmological expansion was originally discovered. (reviews of topical problems)

Beyond the principle of plentitude: a review of terrestrial planet habitability.

Science.gov (United States)

Gaidos, E; Deschenes, B; Dundon, L; Fagan, K; Menviel-Hessler, L; Moskovitz, N; Workman, M

2005-04-01

We review recent work that directly or indirectly addresses the habitability of terrestrial (rocky) planets like the Earth. Habitability has been traditionally defined in terms of an orbital semimajor axis within a range known as the habitable zone, but it is also well known that the habitability of Earth is due to many other astrophysical, geological, and geochemical factors. We focus this review on (1) recent refinements to habitable zone calculations; (2) the formation and orbital stability of terrestrial planets; (3) the tempo and mode of geologic activity (e.g., plate tectonics) on terrestrial planets; (4) the delivery of water to terrestrial planets in the habitable zone; and (5) the acquisition and loss of terrestrial planet carbon and nitrogen, elements that constitute important atmospheric gases responsible for habitable conditions on Earth's surface as well as being the building blocks of the biosphere itself. Finally, we consider recent work on evidence for the earliest habitable environments and the appearance of life itself on our planet. Such evidence provides us with an important, if nominal, calibration point for our search for other habitable worlds.

Closing CMS to hunt cosmic rays

CERN Multimedia

Claudia Marcelloni

2006-01-01

Every second the Earth is bombarded by billions of cosmic rays and occasionally one of these cosmic particles will collide with the Earth's atmosphere generating a shower of particles known as an 'air shower'. This is similiar to the collisions and subsequent particle showers observed in accelerators such as the LHC. Here the CMS detector is closed so that systems can be tested using muon cosmic rays in the 'Cosmic Challenge'.

Radiobiological studies on eggs of the rice weevil (Tribolium confusum) after exposure to heavy primary particles of the cosmic radiation

International Nuclear Information System (INIS)

Geyer, B.

1982-01-01

The thesis explains the radiation effects observed during the holometabolism of Tribolium confusum after exposure of the eggs to heavy primary particles of cosmic radiation, i.e. to atomic nuclei of relatively high energy with a mass greater than helium atoms. The first section describes the technical layout of the BIOSTACK experiment and the fixation of the Tribolium eggs and the positioning of the nuclear track detectors. This part is followed by the description of methods used to detect the eggs hit by the heavy nuclei, and their isolation and subsequent growth. Terrestrial irradiation of eggs with x-rays served as a control, as well as unirradiated egg cultures. The amount of larvae produced from incubated eggs hit by heavy nuclei was 66%, that of eggs exposed to cosmic background radiation was 69%, and that produced by the control culture kept on the earth was 87%. Investigations of egg samples during various stages of embryogenesis showed differences in the histological findings of the various groups, especially between the two groups of the BIOSTACK experiment. The letality of larvae in the period from emergence up to pupal stage was relatively high (50%) in the group hit by heavy nuclei, especially when compared to the other BIOSTACK experimental group, where this percentage was 10%, and to the terrestrial control group (3%). Also, vitality of larvae of the first group was considerably reduced. In the pupal stage, the letality observed in all three test groups was relatively low with 2-4%. From the animals produced from eggs hit by heavy nuclei, only 25% were still alive after 4 months, from the other space flight group these were 75%, and from the terrestrial control group 93%. Also, the animals from the first group showed a significant increase in bodily anomalies. (orig./MG) [de

Program Annual Technology Report: Cosmic Origins Program Office

Science.gov (United States)

Pham, Thai; Neff, Susan

2017-01-01

What is the Cosmic Origins (COR) Program? From ancient times, humans have looked up at the night sky and wondered: Are we alone? How did the universe come to be? How does the universe work? COR focuses on the second question. Scientists investigating this broad theme seek to understand the origin and evolution of the universe from the Big Bang to the present day, determining how the expanding universe grew into a grand cosmic web of dark matter enmeshed with galaxies and pristine gas, forming, merging, and evolving over time. COR also seeks to understand how stars and planets form from clouds in these galaxies to create the heavy elements that are essential to life, starting with the first generation of stars to seed the universe, and continuing through the birth and eventual death of all subsequent generations of stars. The COR Programs purview includes the majority of the field known as astronomy.

Hazards of cosmic radiation; Radiation cosmique: danger dans l'espace

Energy Technology Data Exchange (ETDEWEB)

Bonnet-Bidaud, J M; Dzitko, H

2000-06-01

The main limitations on long-distance space transport is neither the energy source nor the propulsion system but appears to be the protection of cosmonauts from radiation. Cosmic radiation is made up of protons (87%), alpha particles (12%) and heavy nuclei (1%), all these particles travel through interstellar space and come from the explosion of stars at the end of their life. The earth is protected from cosmic radiation by 3 natural shields: (i) the magnetic field generated by the solar wind, (ii) the earth magnetic field (magnetosphere), and (iii) the earth atmosphere, this elusive layer of air is equivalent to a 10 meter-high volume of water. Magnetosphere and atmosphere reduce the radiation dose by a factor 4000. According to a European directive (1996) air crews must be considered as radiation workers. (A.C.)

Interplanetary cosmic-ray scintillations

Energy Technology Data Exchange (ETDEWEB)

Toptygin, I N; Vasiliev, V N [Kalininskij Sel' skokhozyajstvennyj Inst. (USSR)

1977-05-01

The equation for the two-particles cosmic-ray distribution function is derived by means of the Boltzmann kinetic equation averaging. This equation is valid for arbitrary ratio of regular and random parts of the magnetic field. For small energy particles the guiding-center approximation is used. On the basis of the derived equation the dependence between power spectra of cosmic-ray intensity and random magnetic field is obtained. If power spectra are degree functions for high energy particles (approximately 10 GeV nucleon/sup -1/), then the spectral exponent ..gamma.. of magnetic field lies between rho and rho-2, where rho is the spectral exponent of cosmic-ray power spectra. The experimental data concerning moderate energy particles are in accordance with ..gamma..=rho, which demonstrates that the magnetic fluctuations are isotropic or cosmic-ray space gradient is small near the Earth orbit.

Microalgal and terrestrial transport biofuels to displace fossil fuels

NARCIS (Netherlands)

Reijnders, L.

2009-01-01

Terrestrial transport biofuels differ in their ability to replace fossil fuels. When both the conversion of solar energy into biomass and the life cycle inputs of fossil fuels are considered, ethanol from sugarcane and biodiesel from palm oil do relatively well, if compared with ethanol from corn,

ALICE Cosmic Ray Detector

CERN Multimedia

Fernandez Tellez, A; Martinez Hernandez, M; Rodriguez Cahuantzi, M

2013-01-01

The ALICE underground cavern provides an ideal place for the detection of high energy atmospheric muons coming from cosmic ray showers. ACORDE detects cosmic ray showers by triggering the arrival of muons to the top of the ALICE magnet.

Stochastic population dynamics in populations of western terrestrial garter snakes with divergent life histories.

Science.gov (United States)

Miller, David A; Clark, William R; Arnold, Stevan J; Bronikowski, Anne M

2011-08-01

Comparative evaluations of population dynamics in species with temporal and spatial variation in life-history traits are rare because they require long-term demographic time series from multiple populations. We present such an analysis using demographic data collected during the interval 1978-1996 for six populations of western terrestrial garter snakes (Thamnophis elegans) from two evolutionarily divergent ecotypes. Three replicate populations from a slow-living ecotype, found in mountain meadows of northeastern California, were characterized by individuals that develop slowly, mature late, reproduce infrequently with small reproductive effort, and live longer than individuals of three populations of a fast-living ecotype found at lakeshore locales. We constructed matrix population models for each of the populations based on 8-13 years of data per population and analyzed both deterministic dynamics based on mean annual vital rates and stochastic dynamics incorporating annual variation in vital rates. (1) Contributions of highly variable vital rates to fitness (lambda(s)) were buffered against the negative effects of stochastic variation, and this relationship was consistent with differences between the meadow (M-slow) and lakeshore (L-fast) ecotypes. (2) Annual variation in the proportion of gravid females had the greatest negative effect among all vital rates on lambda(s). The magnitude of variation in the proportion of gravid females and its effect on lambda(s) was greater in M-slow than L-fast populations. (3) Variation in the proportion of gravid females, in turn, depended on annual variation in prey availability, and its effect on lambda(s) was 4 23 times greater in M-slow than L-fast populations. In addition to differences in stochastic dynamics between ecotypes, we also found higher mean mortality rates across all age classes in the L-fast populations. Our results suggest that both deterministic and stochastic selective forces have affected the evolution of

Cosmic Humanity: Utopia, Realities, Prospects

Directory of Open Access Journals (Sweden)

Sergey Krichevsky

2017-07-01

Full Text Available The philosophical foundations of the theory and practice of the creation of cosmic humanity as a process of the evolution of human civilization, the emergence into space, with the prospect of resettlement outside the Earth are considered. There is a connection between myths, fantasies, ideas, concepts and projects aimed at the exploration of outer space, the creation of cosmic humanity. A new and voluminous definition of cosmic humanity in the evolutionary paradigm is given. Cosmic humanity is (essence and 4 stages of evolution: 1. Humanity living on Earth, sensing, knowing, understanding its cosmic origin, relationship with the cosmos and cosmic destiny. 2. Humanity living on Earth, leading aerospace activity for the purposes of exploration and use of aerospace space (Heaven, Space for survival and development. 3. Humanity living on Earth and outside the Earth — in the solar system, preserving the Earth and mastering the Cosmos for survival and development. 4. Humanity, settled and living in the Cosmos. Now humanity is in the process of transition from the second to the third stage. In the process of this evolution, a complex transformation of man and society takes place. The problem-semantic field of cosmic humanity is described and its general model is presented. The meta-goal-setting is the justification of cosmic humanity with the application of the anthropic principle and its “active” super (post anthropic supplement: “Cosmic humanity has an evolutionary purpose to actively manage evolution: change man, humanity and the universe.” The evolution of the “cosmic dream”, goals and technologies of space activities is formalized in the form of a conceptual model. Challenges and negative trends are considered in connection with the crisis of space activity, criticism and attempts to limit the flights of people into space. The prototype of cosmic humanity, its basis and acting model is the cosmonauts’ community. The main

The cosmic zoo complex life on many worlds

CERN Document Server

Schulze-Makuch, Dirk

2017-01-01

Are humans a galactic oddity, or will complex life with human abilities develop on planets with environments that remain habitable for long enough? In a clear, jargon-free style, two leading researchers in the burgeoning field of astrobiology critically examine the major evolutionary steps that led us from the distant origins of life to the technologically advanced species we are today. Are the key events that took life from simple cells to astronauts unique occurrences that would be unlikely to occur on other planets? By focusing on what life does - it's functional abilities - rather than specific biochemistry or anatomy, the authors provide plausible answers to this question. Systematically exploring the various pathways that led to the complex biosphere we experience on planet Earth, they show that most of the steps along that path are likely to occur on any world hosting life, with only two exceptions: One is the origin of life itself – if this is a highly improbable event, then we live in a rather “e...

Cosmic Connections:. from Cosmic Rays to Gamma Rays, Cosmic Backgrounds and Magnetic Fields

Science.gov (United States)

Kusenko, Alexander

2013-12-01

Combined data from gamma-ray telescopes and cosmic-ray detectors have produced some new surprising insights regarding intergalactic and galactic magnetic fields, as well as extragalactic background light. We review some recent advances, including a theory explaining the hard spectra of distant blazars and the measurements of intergalactic magnetic fields based on the spectra of distant sources. Furthermore, we discuss the possible contribution of transient galactic sources, such as past gamma-ray bursts and hypernova explosions in the Milky Way, to the observed ux of ultrahigh-energy cosmicrays nuclei. The need for a holistic treatment of gamma rays, cosmic rays, and magnetic fields serves as a unifying theme for these seemingly unrelated phenomena.

Fitting cosmic microwave background data with cosmic strings and inflation.

Science.gov (United States)

Bevis, Neil; Hindmarsh, Mark; Kunz, Martin; Urrestilla, Jon

2008-01-18

We perform a multiparameter likelihood analysis to compare measurements of the cosmic microwave background (CMB) power spectra with predictions from models involving cosmic strings. Adding strings to the standard case of a primordial spectrum with power-law tilt ns, we find a 2sigma detection of strings: f10=0.11+/-0.05, where f10 is the fractional contribution made by strings in the temperature power spectrum (at l=10). CMB data give moderate preference to the model ns=1 with cosmic strings over the standard zero-strings model with variable tilt. When additional non-CMB data are incorporated, the two models become on a par. With variable ns and these extra data, we find that f10<0.11, which corresponds to Gmicro<0.7x10(-6) (where micro is the string tension and G is the gravitational constant).

Some characteristics and effects of natural radiation

International Nuclear Information System (INIS)

Mc Laughlin, J.P.

2015-01-01

Since life first appeared on the Earth, it has, in all its subsequent evolved forms including human, been exposed to natural radiation in the environment both from terrestrial and extra-terrestrial sources. Being an environmental mutagen, ionising natural radiation may have played a role of some significance in the evolution of early life forms on Earth. It has been estimated by United Nations Scientific Committee on the Effects of Atomic Radiation that at the present time, exposure to natural radiation globally results in an annual average individual effective dose of about 2.4 mSv. This represents about 80 % of the total dose from all sources. The three most important components of natural radiation exposure are cosmic radiation, terrestrial radioactivity and indoor radon. Each of these components exhibits both geographical and temporal variabilities with indoor radon exposure being the most variable and also the largest contributor to dose for most people. In this account, an overview is given of the characteristics of the main components of the natural radiation environment and some of their effects on humans. In the case of cosmic radiation, these range from radiation doses to aircrew and astronauts to the controversial topic of its possible effect on climate change. In the case of terrestrial natural radiation, accounts are given of a number of human exposure scenarios. (author)

Cosmogenic Radionuclides in Antarctic Meteorites: Preliminary Results on Terrestrial Ages and Temporal Phenomena

Science.gov (United States)

Michlovich, E.; Vogt, S.; Wolf, S. F.; Elmore, D.; Lipschutz, M. E.

1993-07-01

Since 1969, more than 15,000 meteorites have been recovered from various sites in Antarctica. Differences have been reported between the Antarctic populations and the population of non-Antarctic meteorites in volatile trace- element content, thermoluminescence properties, physical size, and relative distribution of meteorite type [1]. Lipschutz and Samuels [2] developed a method based upon multivariate linear and logistic regression that they applied to interpret trace-element content in Antarctic and non-Antarctic meteorites, showing that the two populations can be chemically distinguished. Since Antarctic meteorites have, on the whole, much longer terrestrial ages than non-Antarctic falls, such differences have been used to support the notion that the flux of meteorites sampled by the Earth has changed in the recent past. A subsequent study [3] showed a statistically significant difference in trace-element content between meteorites from Victoria Land and those found in Queen Maud Land, two groups that seem to have different terrestrial age distributions. Changes in meteorite flux patterns on the order of 60 yr are indicated from a study of Cluster 1 vs. non-Cluster 1 falls [4]. Rapid fluctuations would almost certainly require the existence of co-orbital meteoroid streams, an idea that has been criticized by some [5] on dynamical grounds. To quantify the discussion of a temporal dependence of meteorite flux patterns, and to continue systematic study of Antarctic meteorites, we have measured the contents of the cosmogenic radionuclides ^10Be and ^26Al in the bulk phase, and ^36Cl in the metal phase, of 40 Antarctic specimens that are from the same suite of samples analyzed in the trace-element studies and that were chosen to minimize any chances of paired meteorites. The means and standard deviations of ^10Be and ^26Al activities are 16.4 +/- 3.5 and 48 +/- 8 dpm/kg respectively. Correction for cosmic ray exposure [6,7] and terrestrial ages allows us to estimate

Department of Cosmic Ray Physics: Overview

International Nuclear Information System (INIS)

Szabelski, J.

2001-01-01

Full text: The Department of Cosmic Ray Physics in Lodz is involved in basic research in the area of high-energy physics and cosmic ray physics related to: Experimental and phenomenological studies of Extensive Air Showers induced by cosmic ray particles. Studies of ultra-high energy (above 10 19 eV) cosmic rays: determination of energy and primary particle mass composition. Studies of asymptotic properties of hadronic interactions based on the analysis of cosmic ray propagation through the atmosphere. Studies of mass composition of cosmic rays in the energy range 10 15 -10 17 eV. Registration of cosmic ray intensity variation correlated with solar activity. Theoretical and experimental studies of Extensive Air Shower properties are performed mostly based on the results obtained by the Lodz Extensive Air Shower Array. We have noticed unexplainable delayed signals registered about 500-900 microseconds after the main EAS pulse. We prepared hardware for further experimental study of this effect. In September we have started registration of 5 GeV muon flux with the underground muon telescope. We registered 3 decreases of muon intensity correlated with Forbush decreases registered at lower energies. Variations of primary cosmic ray of energies up to about 100 GeV were responsible for our registrations. These set the upper limits for geometrical size of geomagnetic disturbances in interplanetary space. In construction and data interpretation of cosmic ray experiments, the Lodz group collaborates with many foreign institutes and laboratories: Forschungszentrum in Karlsruhe (Germany), College de France, Institute for Nuclear Studies of the Russian Academy of Sciences and Uppsala University (Sweden). We have organised (together with the Physics Department of the University of Lodz) the 17 th European Cosmic Ray Symposium (24-?8 July 2000) in which about 150 physicists participated (about 100 from abroad). (author)

Impact of an asteroid or comet in the ocean and extinction of terrestrial life

Science.gov (United States)

Ahrens, T. J.; Okeefe, J. D.

1982-01-01

Finite difference calculations describing the impact mechanics associated with a 10 to 30 km diameter silicate or water object impacting a 5 km deep ocean overlying a silicate solid planet demonstrate that from 12 to 15% of the bolide energy resides in the water. It is speculated that minimal global tsunami run-up heights on the continents would be 300-400 meters, and that such waves would inundate all low altitude continental areas, and strip and silt-over virtually all vegetation. As a result the terrestrial animal food chain would be seriously perturbed. This could in turn cause extinction of large terrestrial animals.

Cosmic physics: the high energy frontier

International Nuclear Information System (INIS)

Stecker, F W

2003-01-01

Cosmic rays have been observed up to energies 10 8 times larger than those of the best particle accelerators. Studies of astrophysical particles (hadrons, neutrinos and photons) at their highest observed energies have implications for fundamental physics as well as astrophysics. Thus, the cosmic high energy frontier is the nexus to new particle physics. This overview discusses recent advances being made in the physics and astrophysics of cosmic rays and cosmic γ-rays at the highest observed energies as well as the related physics and astrophysics of very high energy cosmic neutrinos. These topics touch on questions of grand unification, violations of Lorentz invariance as well as Planck scale physics and quantum gravity. (topical review)

Cosmic rays and global warming

Energy Technology Data Exchange (ETDEWEB)

Erlykin, A.D. [P.N. Lebedev Physical Institute, Moscow (Russian Federation); Sloan, T. [Lancaster University (United Kingdom); Wolfendale, A.W. [Durham University (United Kingdom)

2010-07-01

The possible effects of cosmic rays on clouds could contribute to global warming. The argument is that the observed increased solar activity during the last century caused a decrease in the ionization due to cosmic rays since the lower energy cosmic particles are deflected by the magnetic field created by the increasing solar wind. This would lead to a decrease in cloud cover allowing more heating of the earth by the sun. Meteorological data combined to solar activity observations and simulations show that any effect of solar activity on clouds and the climate is likely to be through irradiance rather than cosmic rays. Since solar irradiance transfers 8 orders of magnitude more energy to the atmosphere than cosmic rays it is more plausible that this can produce a real effect. The total contribution of variable solar activity to global warming is shown to be less than 14% of the total temperature rise. (A.C.)

Impact of Cosmic-Ray Transport on Galactic Winds

Science.gov (United States)

Farber, R.; Ruszkowski, M.; Yang, H.-Y. K.; Zweibel, E. G.

2018-04-01

The role of cosmic rays generated by supernovae and young stars has very recently begun to receive significant attention in studies of galaxy formation and evolution due to the realization that cosmic rays can efficiently accelerate galactic winds. Microscopic cosmic-ray transport processes are fundamental for determining the efficiency of cosmic-ray wind driving. Previous studies modeled cosmic-ray transport either via a constant diffusion coefficient or via streaming proportional to the Alfvén speed. However, in predominantly cold, neutral gas, cosmic rays can propagate faster than in the ionized medium, and the effective transport can be substantially larger; i.e., cosmic rays can decouple from the gas. We perform three-dimensional magnetohydrodynamical simulations of patches of galactic disks including the effects of cosmic rays. Our simulations include the decoupling of cosmic rays in the cold, neutral interstellar medium. We find that, compared to the ordinary diffusive cosmic-ray transport case, accounting for the decoupling leads to significantly different wind properties, such as the gas density and temperature, significantly broader spatial distribution of cosmic rays, and higher wind speed. These results have implications for X-ray, γ-ray, and radio emission, and for the magnetization and pollution of the circumgalactic medium by cosmic rays.

Cosmic Topology

Science.gov (United States)

Luminet, Jean-Pierre

2015-08-01

Cosmic Topology is the name given to the study of the overall shape of the universe, which involves both global topological features and more local geometrical properties such as curvature. Whether space is finite or infinite, simply-connected or multi-connected like a torus, smaller or greater than the portion of the universe that we can directly observe, are questions that refer to topology rather than curvature. A striking feature of some relativistic, multi-connected "small" universe models is to create multiples images of faraway cosmic sources. While the most recent cosmological data fit the simplest model of a zero-curvature, infinite space model, they are also consistent with compact topologies of the three homogeneous and isotropic geometries of constant curvature, such as, for instance, the spherical Poincaré Dodecahedral Space, the flat hypertorus or the hyperbolic Picard horn. After a "dark age" period, the field of Cosmic Topology has recently become one of the major concerns in cosmology, not only for theorists but also for observational astronomers, leaving open a number of unsolved issues.

Cosmic ray physics goes to school

CERN Multimedia

2002-01-01

With the help of a CERN physicist, German Schools bring the Largest Cosmic Ray Detector in Europe one step closer to reality   Eric Berthier and Robert Porret (CERN, ST/HM), Frej Torp and Christian Antfolk from the Polytechnics Arcada in Finland, and Karsten Eggert, physicist at CERN who initiated this project, during the installation of cosmic ray detectors in the Pays de Gex, at point 4. Niina Patrikainen and Frej Torp, Finnish students from Rovaniemi and Arcada Polytechnics, installing cosmic ray counters at the Fachhochschule in Duesseldorf. The science of cosmic ray detection is growing, literally. Cosmic rays, energetic particles from space, strike our planet all the time. They collide with the air molecules in our upper atmosphere and initiate large showers of elementary particles (mainly electrons, photons, hadrons and muons) which rain down upon the earth. The shower size and the particle density in the showers reflect the initial energy of the cosmic ray particle, a detail which makes d...

Evaluation of meteorites as habitats for terrestrial microorganisms: Results from the Nullarbor Plain, Australia, a Mars analogue site

Science.gov (United States)

Tait, Alastair W.; Wilson, Siobhan A.; Tomkins, Andrew G.; Gagen, Emma J.; Fallon, Stewart J.; Southam, Gordon

2017-10-01

Unambiguous identification of biosignatures on Mars requires access to well-characterized, long-lasting geochemical standards at the planet's surface that can be modified by theoretical martian life. Ordinary chondrites, which are ancient meteorites that commonly fall to the surface of Mars and Earth, have well-characterized, narrow ranges in trace element and isotope geochemistry compared to martian rocks. Given that their mineralogy is more attractive to known chemolithotrophic life than the basaltic rocks that dominate the martian surface, exogenic rocks (e.g., chondritic meteorites) may be good places to look for signs of prior life endemic to Mars. In this study, we show that ordinary chondrites, collected from the arid Australian Nullarbor Plain, are commonly colonized and inhabited by terrestrial microorganisms that are endemic to this Mars analogue site. These terrestrial endolithic and chasmolithic microbial contaminants are commonly found in close association with hygroscopic veins of gypsum and Mg-calcite, which have formed within cracks penetrating deep into the meteorites. Terrestrial bacteria are observed within corrosion cavities, where troilite (FeS) oxidation has produced jarosite [KFe3(SO4)2(OH)6]. Where terrestrial microorganisms have colonized primary silicate minerals and secondary calcite, these mineral surfaces are heavily etched. Our results show that inhabitation of meteorites by terrestrial microorganisms in arid environments relies upon humidity and pH regulation by minerals. Furthermore, microbial colonization affects the weathering of meteorites and production of sulfate, carbonate, Fe-oxide and smectite minerals that can preserve chemical and isotopic biosignatures for thousands to millions of years on Earth. Meteorites are thus habitable by terrestrial microorganisms, even under highly desiccating environmental conditions of relevance to Mars. They may therefore be useful as chemical and isotopic ;standards; that preserve evidence of

Separation of gravitational-wave and cosmic-shear contributions to cosmic microwave background polarization.

Science.gov (United States)

Kesden, Michael; Cooray, Asantha; Kamionkowski, Marc

2002-07-01

Inflationary gravitational waves (GW) contribute to the curl component in the polarization of the cosmic microwave background (CMB). Cosmic shear--gravitational lensing of the CMB--converts a fraction of the dominant gradient polarization to the curl component. Higher-order correlations can be used to map the cosmic shear and subtract this contribution to the curl. Arcminute resolution will be required to pursue GW amplitudes smaller than those accessible by the Planck surveyor mission. The blurring by lensing of small-scale CMB power leads with this reconstruction technique to a minimum detectable GW amplitude corresponding to an inflation energy near 10(15) GeV.

Terrestrial Analogs to Mars: NRC Community Panel Decadal Report

Science.gov (United States)

Farr, T. G.

2002-12-01

A report was completed recently by a Community Panel for the NRC Decadal Study of Solar System Exploration. The desire was for a review of the current state of knowledge and for recommendations for action over the next decade. The topic of this panel, Terrestrial Analogs to Mars, was chosen to bring attention to the need for an increase in analog studies in support of the increased pace of Mars exploration. It is well recognized that interpretations of Mars must begin with the Earth as a reference. The most successful comparisons have focused on understanding geologic processes on the Earth well enough to extrapolate to Mars' environment. Several facets of terrestrial analog studies have been pursued and are continuing. These studies include field workshops, characterization of terrestrial analog sites, instrument tests, laboratory measurements (including analysis of martian meteorites), and computer and laboratory modeling. The combination of all of these activities allows scientists to constrain the processes operating in specific terrestrial environments and extrapolate how similar processes could affect Mars. The Terrestrial Analogs for Mars Community Panel has considered the following two key questions: (1) How do terrestrial analog studies tie in to the overarching science questions about life, past climate, and geologic evolution of Mars, and (2) How can future instrumentation be used to address these questions. The panel considered the issues of data collection and archiving, value of field workshops, laboratory measurements and modeling, human exploration issues, association with other areas of solar system exploration, and education and public outreach activities. Parts of this work were performed under contract to NASA.

Cosmic rays and the interstellar medium

International Nuclear Information System (INIS)

Wolfendale, A.W.

1986-01-01

It is inevitable that there is a close connection between cosmic rays and the ISM insofar as the propagation of cosmic rays is conditioned by the magnetic field in the ISM and the cosmic rays interact with the gas (and photon fluxes) in this medium. This paper deals with both topics. Propagation effects manifest themselves as an anisotropy in arrival directions and a review is given of anisotropy measurements and their interpretation. The status of studies of cosmic ray interactions is examined whit particular reference to the information about the ISM itself which comes from observations of the flux of secondary γ-rays produced by cosmic ray interactions with gas, the situation regarding molecular as in the Inner Galaxy being of particular concern

Looking for Cosmic Neutrino Background

Directory of Open Access Journals (Sweden)

Chiaki eYanagisawa

2014-06-01

Full Text Available Since the discovery of neutrino oscillation in atmospheric neutrinos by the Super-Kamiokande experiment in 1998, study of neutrinos has been one of exciting fields in high-energy physics. All the mixing angles were measured. Quests for 1 measurements of the remaining parameters, the lightest neutrino mass, the CP violating phase(s, and the sign of mass splitting between the mass eigenstates m3 and m1, and 2 better measurements to determine whether the mixing angle theta23 is less than pi/4, are in progress in a well-controlled manner. Determining the nature of neutrinos, whether they are Dirac or Majorana particles is also in progress with continuous improvement. On the other hand, although the ideas of detecting cosmic neutrino background have been discussed since 1960s, there has not been a serious concerted effort to achieve this goal. One of the reasons is that it is extremely difficult to detect such low energy neutrinos from the Big Bang. While there has been tremendous accumulation of information on Cosmic Microwave Background since its discovery in 1965, there is no direct evidence for Cosmic Neutrino Background. The importance of detecting Cosmic Neutrino Background is that, although detailed studies of Big Bang Nucleosynthesis and Cosmic Microwave Background give information of the early Universe at ~a few minutes old and ~300 k years old, respectively, observation of Cosmic Neutrino Background allows us to study the early Universe at $sim$ 1 sec old. This article reviews progress made in the past 50 years on detection methods of Cosmic Neutrino Background.

A method of detector correction for cosmic ray muon radiography

International Nuclear Information System (INIS)

Liu Yuanyuan; Zhao Ziran; Chen Zhiqiang; Zhang Li; Wang Zhentian

2008-01-01

Cosmic ray muon radiography which has good penetrability and sensitivity to high-Z materials is an effective way for detecting shielded nuclear materials. The problem of data correction is one of the key points of muon radiography technique. Because of the influence of environmental background, environmental yawp and error of detectors, the raw data can not be used directly. If we used the raw data as the usable data to reconstruct without any corrections, it would turn up terrible artifacts. Based on the characteristics of the muon radiography system, aimed at the error of detectors, this paper proposes a method of detector correction. The simulation experiments demonstrate that this method can effectively correct the error produced by detectors. Therefore, we can say that it does a further step to let the technique of cosmic muon radiography into out real life. (authors)

Broken symmetries at the origin of matter, at the origin of life and at the origin of culture

International Nuclear Information System (INIS)

Klinken, J. van

1998-01-01

In earliest cosmic history the universe started with matter and not with antimatter. Shortly after the beginning the electroweak interaction - prominent in nuclear β decay - acted as a left-hander. Much later, in pre biotic evolution, optically left-handed amino acids determined the unique signature of following terrestrial organic life. Again ae- ons later, homo sapiens appears as predominantly right handed and creates cultures with many broken symmetries. Along these pathways of history it was essential that choices were made - left or right, matter or antimatter - but on several instances it seemed less relevant which choice were made. We think that biochirality occurred by global chance; perhaps by local necessity, but without causal links to the PCT theorem. In other cases - e.g. the standardization to right-handed screws - the choice will have been made by causal necessity. (author)

Microalgal and Terrestrial Transport Biofuels to Displace Fossil Fuels

Directory of Open Access Journals (Sweden)

Lucas Reijnders

2009-02-01

Full Text Available Terrestrial transport biofuels differ in their ability to replace fossil fuels. When both the conversion of solar energy into biomass and the life cycle inputs of fossil fuels are considered, ethanol from sugarcane and biodiesel from palm oil do relatively well, if compared with ethanol from corn, sugar beet or wheat and biodiesel from rapeseed. When terrestrial biofuels are to replace mineral oil-derived transport fuels, large areas of good agricultural land are needed: about 5x108 ha in the case of biofuels from sugarcane or oil palm, and at least 1.8-3.6x109 ha in the case of ethanol from wheat, corn or sugar beet, as produced in industrialized countries. Biofuels from microalgae which are commercially produced with current technologies do not appear to outperform terrestrial plants such as sugarcane in their ability to displace fossil fuels. Whether they will able to do so on a commercial scale in the future, is uncertain.

Ionizing radiation and life.

Science.gov (United States)

Dartnell, Lewis R

2011-01-01

Ionizing radiation is a ubiquitous feature of the Cosmos, from exogenous cosmic rays (CR) to the intrinsic mineral radioactivity of a habitable world, and its influences on the emergence and persistence of life are wide-ranging and profound. Much attention has already been focused on the deleterious effects of ionizing radiation on organisms and the complex molecules of life, but ionizing radiation also performs many crucial functions in the generation of habitable planetary environments and the origins of life. This review surveys the role of CR and mineral radioactivity in star formation, generation of biogenic elements, and the synthesis of organic molecules and driving of prebiotic chemistry. Another major theme is the multiple layers of shielding of planetary surfaces from the flux of cosmic radiation and the various effects on a biosphere of violent but rare astrophysical events such as supernovae and gamma-ray bursts. The influences of CR can also be duplicitous, such as limiting the survival of surface life on Mars while potentially supporting a subsurface biosphere in the ocean of Europa. This review highlights the common thread that ionizing radiation forms between the disparate component disciplines of astrobiology. © Mary Ann Liebert, Inc.

Cosmic strings and galaxy formation

Science.gov (United States)

Bertschinger, Edmund

1989-01-01

The cosmogonical model proposed by Zel'dovich and Vilenkin (1981), in which superconducting cosmic strings act as seeds for the origin of structure in the universe, is discussed, summarizing the results of recent theoretical investigations. Consideration is given to the formation of cosmic strings, the microscopic structure of strings, gravitational effects, cosmic string evolution, and the formation of galaxies and large-scale structure. Simulation results are presented in graphs, and several outstanding issues are listed and briefly characterized.

The cosmic spiderweb: equivalence of cosmic, architectural and origami tessellations

Science.gov (United States)

Neyrinck, Mark C.; Hidding, Johan; Konstantatou, Marina; van de Weygaert, Rien

2018-04-01

For over 20 years, the term `cosmic web' has guided our understanding of the large-scale arrangement of matter in the cosmos, accurately evoking the concept of a network of galaxies linked by filaments. But the physical correspondence between the cosmic web and structural engineering or textile `spiderwebs' is even deeper than previously known, and also extends to origami tessellations. Here, we explain that in a good structure-formation approximation known as the adhesion model, threads of the cosmic web form a spiderweb, i.e. can be strung up to be entirely in tension. The correspondence is exact if nodes sampling voids are included, and if structure is excluded within collapsed regions (walls, filaments and haloes), where dark-matter multistreaming and baryonic physics affect the structure. We also suggest how concepts arising from this link might be used to test cosmological models: for example, to test for large-scale anisotropy and rotational flows in the cosmos.

The cosmic spiderweb: equivalence of cosmic, architectural and origami tessellations.

Science.gov (United States)

Neyrinck, Mark C; Hidding, Johan; Konstantatou, Marina; van de Weygaert, Rien

2018-04-01

For over 20 years, the term 'cosmic web' has guided our understanding of the large-scale arrangement of matter in the cosmos, accurately evoking the concept of a network of galaxies linked by filaments. But the physical correspondence between the cosmic web and structural engineering or textile 'spiderwebs' is even deeper than previously known, and also extends to origami tessellations. Here, we explain that in a good structure-formation approximation known as the adhesion model, threads of the cosmic web form a spiderweb, i.e. can be strung up to be entirely in tension. The correspondence is exact if nodes sampling voids are included, and if structure is excluded within collapsed regions (walls, filaments and haloes), where dark-matter multistreaming and baryonic physics affect the structure. We also suggest how concepts arising from this link might be used to test cosmological models: for example, to test for large-scale anisotropy and rotational flows in the cosmos.

The cosmic spiderweb: equivalence of cosmic, architectural and origami tessellations

Science.gov (United States)

Hidding, Johan; Konstantatou, Marina; van de Weygaert, Rien

2018-01-01

For over 20 years, the term ‘cosmic web’ has guided our understanding of the large-scale arrangement of matter in the cosmos, accurately evoking the concept of a network of galaxies linked by filaments. But the physical correspondence between the cosmic web and structural engineering or textile ‘spiderwebs’ is even deeper than previously known, and also extends to origami tessellations. Here, we explain that in a good structure-formation approximation known as the adhesion model, threads of the cosmic web form a spiderweb, i.e. can be strung up to be entirely in tension. The correspondence is exact if nodes sampling voids are included, and if structure is excluded within collapsed regions (walls, filaments and haloes), where dark-matter multistreaming and baryonic physics affect the structure. We also suggest how concepts arising from this link might be used to test cosmological models: for example, to test for large-scale anisotropy and rotational flows in the cosmos. PMID:29765637

Hazards of cosmic radiation; Radiation cosmique: danger dans l'espace

Energy Technology Data Exchange (ETDEWEB)

Bonnet-Bidaud, J.M.; Dzitko, H

2000-06-01

The main limitations on long-distance space transport is neither the energy source nor the propulsion system but appears to be the protection of cosmonauts from radiation. Cosmic radiation is made up of protons (87%), alpha particles (12%) and heavy nuclei (1%), all these particles travel through interstellar space and come from the explosion of stars at the end of their life. The earth is protected from cosmic radiation by 3 natural shields: (i) the magnetic field generated by the solar wind, (ii) the earth magnetic field (magnetosphere), and (iii) the earth atmosphere, this elusive layer of air is equivalent to a 10 meter-high volume of water. Magnetosphere and atmosphere reduce the radiation dose by a factor 4000. According to a European directive (1996) air crews must be considered as radiation workers. (A.C.)

Cosmic Deuterium and Social Networking Software

Science.gov (United States)

Pasachoff, J. M.; Suer, T.-A.; Lubowich, D. A.; Glaisyer, T.

2006-08-01

For the education of newcomers to a scientific field and for the convenience of students and workers in the field, it is helpful to have all the basic scientific papers gathered. For the study of deuterium in the Universe, in 2004-5 we set up http://www.cosmicdeuterium.info with clickable links to all the historic and basic papers in the field and to many of the current papers. Cosmic deuterium is especially important because all deuterium in the Universe was formed in the epoch of nucleosynthesis in the first 1000 seconds after the Big Bang, so study of its relative abundance (D:H~1:100,000) gives us information about those first minutes of the Universe's life. Thus the understanding of cosmic deuterium is one of the pillars of modern cosmology, joining the cosmic expansion, the 3 degree cosmic background radiation, and the ripples in that background radiation. Studies of deuterium are also important for understanding Galactic chemical evolution, astrochemistry, interstellar processes, and planetary formation. Some papers had to be scanned while others are available at the Astrophysical Data System, adswww.harvard.edu, or to publishers' Websites. By 2006, social networking software (http:tinyurl.com/ zx5hk) had advanced with popular sites like facebook.com and MySpace.com; the Astrophysical Data System had even set up MyADS. Social tagging software sites like http://del.icio.us have made it easy to share sets of links to papers already available online. We have set up http://del.icio.us/deuterium to provide links to many of the papers on cosmicdeuterium.info, furthering previous del.icio.us work on /eclipses and /plutocharon. It is easy for the site owner to add links to a del.icio.us site; it takes merely clicking on a button on the browser screen once the site is opened and the desired link is viewed in a browser. Categorizing different topics by keywords allows subsets to be easily displayed. The opportunity to expose knowledge and build an ecosystem of web

Department of Cosmic Ray Physics; Overview

International Nuclear Information System (INIS)

Szabelski, J.

2004-01-01

Full text: Cosmic Rays are energetic particles from outside the Solar System. The energy spectrum (power law energy dependence) suggests a non-thermal origin of these particles. Most of the studies of Cosmic Rays address fundamental problems such as: - the nature of the physical and astrophysical processes responsible for the high energies of particles (up to about 10 20 eV/particle), - estimation of the astrophysical conditions at the acceleration sites and/or a search for sources of Cosmic Rays, - properties of high energy particle interactions at very high energies (nuclear interactions at energies exceeding energies available in the laboratories). Some Cosmic Ray studies might have practical (commercial) implications, e.g. - ''cosmic weather'' forecast - predictions of geomagnetic disturbances related to Solar activity changes (due to large Solar Flares / events of Coronal Mass Ejections); these are important for large electricity networks, gas pipes, radio-wave connections, space missions and satellite experiments. The Department of Cosmic Ray Physics in Lodz is involved in basic research in the high energy Cosmic Ray field. Energetic Cosmic Ray particles produce cascades of particles in the atmosphere, called Extensive Air Showers (EAS). Registering EAS and their properties is the main theme of experimental studies of very high energy Cosmic Rays. In the Lodz Department we run an Extensive Air Shower array where EAS are registered. We concentrate our experimental research on the explanation of particle detection delayed by hundreds of microseconds with respect to the main EAS signals. In the underground (I5 meters) laboratory we continuously register muon (5 GeV energy threshold) flux with the multidirectional telescope. We have observed several disturbances (Forbush Decreases) in muon counting rates. The interpretation of these events for ''cosmic weather'' and for Cosmic Ray transport models in the interplanetary plasma are on going in collaboration with

Department of Cosmic Ray Physics - Overview

International Nuclear Information System (INIS)

Szabelski, J.

2010-01-01

Full text: The 31 st International Cosmic Ray Conference (31.ICRC) was held in Lodz on 7-15 July 2009. The Conference was organized by the University of Lodz (Department of High Energy Astrophysics and Department of Astrophysics) and IPJ (Department of Cosmic Ray Physics). ICRCs are held every two years and are the largest forums to present and discuss the current status of Cosmic Ray studies. The Conference we co-organized gathered about 750 scientists (including about 50 from Poland). This was a remarkable event. The Department of Cosmic Ray Physics in Lodz is involved in basic research in the field of high energy Cosmic Rays. Cosmic Rays are energetic panicles from outside the Solar System. Most studies of Cosmic Rays address fundamental problems: - the nature of the physical and astrophysical processes responsible for the high energies of the particles. - experimental search for sources of Cosmic Rays, - studies of the astrophysical conditions at the acceleration sites, - properties of particle interactions at very high energies. Presentation of Cosmic Ray registration to high school students has become a popular way to introduce panicle physics detectors and elementary particle detection techniques to young people, in Lodz and Poznan we organize workshops on particle physics for high school students. This is part of the European activity: EPPOG Masterclass - Hands on CERN. Energetic Cosmic Ray particles produce cascades of panicles in the atmosphere, called Extensive Air Showers (EAS). Registering EASs and their properties is the main means of studying experimentally high energy Cosmic Rays: · The satellite experiment JEM-EUSO will observe EASs from the International Space Station. The main target is to find Cosmic Ray Sources for the highest energy Cosmic Rays. JEM-EUSO will collect a large number of events since it will observe a large area of the atmosphere. We are participating in the preparation of this mission. · The KASCADE-Grande addresses

PROTECTION FROM COSMIC RADIATION IN LONG-TERM MANNED SPACEFLIGHTS

Directory of Open Access Journals (Sweden)

Marco Durante

2012-06-01

Full Text Available Current space programs are shifting toward planetary exploration, and in particular towards human missions to the moon and Mars. Space radiation, comprised of energetic protons and heavy nuclei, has been shown to produce distinct biological damage compared to radiation on Earth, leading to large uncertainties in the projection of health risks. Even if uncertainties in risk assessment will be reduced in the next few years, there is little doubt that appropriate countermeasures have to be taken to reduce the exposure or the biological damage produced by cosmic radiation. In addition, it is necessary to provide effective countermeasures against solar particle events, which can produce acute effects, even life threatening, for inadequately protected crews. Unfortunately, passive (bulk shielding is currently unable to provide adequate protection, because cosmic rays have very high energy and nuclear fragmentation in the absorbers produce light fragments. Material science could provide new materials with better shielding properties for space radiation. Active (magnetic shielding could be an interesting alternative, pending technical improvements.

The limits of extremophilic life expanded under extraterrestrial environment-simulated experiments

Science.gov (United States)

Lage, C.; Dalmaso, G.; Teixeira, L.; Bendia, A.; Rosado, A.

2012-09-01

Astrobiology is a brand new area of science that seeks to understand the origin and dynamics of life in the universe. Several hypotheses to explain life in the cosmic context have been developed throughout human history, but only now technology has allowed many of them to be tested. Laboratory experiments have been able to show how chemical elements essential to life, carbon, nitrogen, oxygen and hydrogen combine in biologically important compounds. Interestingly, these compounds are found universally. As these compounds were combined to the point of originating cells and complex organisms is still a challenge to be unveiled by science. However, our 4.5 billion years-old solar system was born within a 10-billion years-old universe. Thus, simple cells like microorganisms may have had time to form in planets older than ours or other suitable molecular places in the universe. One hypothesis to explain the origin of life on Earth is called panspermia, which predicts that microbial life could have been formed in the universe billions of years ago, traveling between planets, and inseminating units of life that could have become more complex in habitable planets like ours. A project designed to test the viability of extremophile microorganisms exposed to simulated extraterrestrial environments is ongoing at the Carlos Chagas Filho Institute of Biophysics to test whether microbial life could withstand those inhospitable environments. Ultra-resistant (known or novel ones) microorganisms collected from terrestrial extreme environments, extremophiles, have been exposed to intense radiation sources simulating solar radiation (at synchrotron accelerators), capable of emitting in a few hours radiation equivalent of million years accumulated doses. The results obtained in these experiments reveal the interesting possibility of the existence of microbial life beyond Earth.

Cosmic antimatter

International Nuclear Information System (INIS)

Tarle, G.; Swordy, S.

1998-01-01

In 1928 Paul Dirac forecasted the existence of antimatter and 4 years later Carl Anderson detected the first antiparticle: the positron in a cloud chamber while studying cosmic radiation. Antiprotons were more difficult to find but in 1955 physicists from Lawrence Berkeley Laboratory got some in a particle accelerator. In 1995 a team from the CERN synthesized atoms of anti-hydrogen by binding positrons to antiprotons in a particle accelerator. Astrophysicists have built more and more complex detectors to study cosmic rays. The detector HEAT (high energy antimatter telescope) has been designed to study positrons above the atmosphere. This detector has been launched for the first time in 1994 and has measured cosmic radiation for 32 hours at an altitude of 37000 meters. The results were challenging: whereas the number of low energy positrons detected agrees with the theory, the number of high energy positrons is too important. It suggests the existence of unknown sources of positrons somewhere in the universe. The massive particles that interact weakly (WIMP) could be such sources. This article draws the history of the quest for antimatter and its implications in cosmology, the detector HEAT is described. (A.C.)

The coronas-F space mission key results for solar terrestrial physics

CERN Document Server

2014-01-01

This volume is the updated and extended translation of the Russian original. It presents the results of observations of solar activity and its effects in the Earth space environment carried out from July 2001 to December 2005 on board the CORONAS-F space mission. The general characteristics of the CORONAS-F scientific payload are provided with a description of the principal experiments. The main results focus on the global oscillations of the Sun (p-modes), solar corona, solar flares, solar cosmic rays, Earth’s radiation belts, and upper atmosphere. The book will be welcomed by students, post-graduates, and scientists working in the field of solar and solar-terrestrial physics. This English edition is supplemented by sections presenting new results of the SPIRIT and TESIS experiments under the CORONAS solar program, as well as from the SONG experiment onboard the CORONAS-F satellite.

Primary cosmic ray flux

Energy Technology Data Exchange (ETDEWEB)

Stanev, Todor

2001-05-01

We discuss the primary cosmic ray flux from the point of view of particle interactions and production of atmospheric neutrinos. The overall normalization of the cosmic ray flux and its time variations and site dependence are major ingredients of the atmospheric neutrino predictions and the basis for the derivation of the neutrino oscillation parameters.

Spatial and temporal variability across life's hierarchies in the terrestrial Antarctic

OpenAIRE

Chown, Steven L; Convey, Peter

2007-01-01

Antarctica and its surrounding islands lie at one extreme of global variation in diversity. Typically, these regions are characterized as being species poor and having simple food webs. Here, we show that terrestrial systems in the region are nonetheless characterized by substantial spatial and temporal variations at virtually all of the levels of the genealogical and ecological hierarchies which have been thoroughly investigated. Spatial variation at the individual and population levels has ...

A half-century of terrestrial analog studies: From craters on the Moon to searching for life on Mars

Science.gov (United States)

Léveillé, Richard

2010-03-01

Terrestrial analogs to the Moon and Mars have been used to advance knowledge in planetary science for over a half-century. They are useful in studies of comparative geology of the terrestrial planets and rocky moons, in astronaut training and testing of exploration technologies, and in developing hypotheses and exploration strategies in astrobiology. In fact, the use of terrestrial analogs can be traced back to the origins of comparative geology and astrobiology, and to the early phases of the Apollo astronaut program. Terrestrial analog studies feature prominently throughout the history of both NASA and the USGS' Astrogeology Research Program. In light of current international plans for a return missions to the Moon, and eventually to send sample return and manned missions to Mars, as well as the recent creation of various analog research and development programs, this historical perspective is timely.

Cosmic Ray Physics with ACORDE at LHC

CERN Document Server

Pagliarone, C.

2008-01-01

The use of large underground high-energy physics experiments, for comic ray studies, have been used, in the past, at CERN, in order to measure, precisely, the inclusive cosmic ray flux in the energy range from 2x10^10 - 2x10^12 eV. ACORDE, ALICE Cosmic Rays DEtector, will act as Level 0 cosmic ray trigger and, together with other ALICE apparatus, will provide precise information on cosmic rays with primary energies around 10^15 - 10^17 eV. This paper reviews the main detector features, the present status, commissioning and integration with other apparatus. Finally, we discuss the ACORDE-ALICE cosmic ray physics program.

Cosmic ray physics with ACORDE at LHC

International Nuclear Information System (INIS)

Pagliarone, C; Fernandez-Tellez, A

2008-01-01

The use of large underground high-energy physics experiments, for comic ray studies, have been used, in the past, at CERN, in order to measure, precisely, the inclusive cosmic ray flux in the energy range from 2·10 10 to 2· 10 12 eV. ACORDE, ALICE Cosmic Rays DEtector, will act as Level 0 cosmic ray trigger and, together with other ALICE apparatus, will provide precise information on cosmic rays with primary energies around 10 15 to 10 17 eV. This paper reviews the main detector features, the present status, commissioning and integration with other apparatus. Finally, we discuss the ACORDE-ALICE cosmic ray physics program

Do negative life events promote gerotranscendence in the second half of life?

NARCIS (Netherlands)

Read, S.; Braam, A.W.; Lyyra, T.M.; Deeg, D.J.H.

2014-01-01

Objectives: Gerotranscendence has been defined as a developmental shift in meta-perspective from a materialistic and pragmatic view to a more cosmic and transcendent view. Although gerotranscendence has been argued to increase with age and life experiences, the results have been mixed and based on

Department of Cosmic Ray Physics; Overview

International Nuclear Information System (INIS)

Szabelski, J.

2003-01-01

Full text: Department of Cosmic Ray Physics in Lodz is involved in basic research in the area of high-energy physics and cosmic ray physics related to: - Experimental and phenomenological studies of Extensive Air Showers induced by cosmic ray particles. - Studies of ultra-high energy (above 10 19 eV) cosmic rays: determination of energy spectrum and mass composition of primary particles - Studies of asymptotic properties of hadronic interactions based on the analysis of cosmic ray propagation through the atmosphere. - Studies of mass composition of cosmic rays in the energy range 10 15 - 10 17 eV. - Registration of cosmic ray intensity variation correlated with solar activity. Theoretical and experimental studies of Extensive Air Shower properties are performed mostly basing on the results obtained by the Lodz Extensive Air Shower Array. We have noticed unexplainable delayed signals registered about 500-900 microseconds after the main EAS pulse. Neutron transport simulations were performed in collaboration with JINR in Dubna. We prepared hardware for further experimental study of this effect. Continuous registrations of 5 GeV muon flux with the underground muon telescope have been carried on over the year 2001. We have detected several changes of muon intensity correlated with Forbush decreases registered at lower energies. We have also started registrations of muon counting rate in the on-surface scintillation detectors. These measurements will be included to the analysis of the disturbed energy spectrum of primary cosmic rays and its dependence on interplanetary disturbances related to the solar activity. In construction and data interpretation of cosmic ray experiments the Lodz group collaborates with many foreign institutes and laboratories: Forschungszentrum in Karlsruhe (Germany), College de France, Institute for Nuclear Studies of the Russian Academy of Sciences, JINR in Dubna (Russia), Uppsala University (Sweden) and DESY (Germany). We have prepared a

Department of Cosmic Ray Physics: Overview

International Nuclear Information System (INIS)

Szabelski, J.

2002-01-01

Full text:The Department of Cosmic Ray Physics in Lodz is involved in basic research in the area of high-energy physics and cosmic ray physics related to: * Experimental and phenomenological studies of Extensive Air Showers induced by cosmic ray particles. * Studies of ultra-high energy (above 10 19 eV) cosmic rays: determination of energy spectrum and mass composition of primary particles * Studies of asymptotic properties of hadronic interactions based on the analysis of cosmic ray propagation through the atmosphere. * Studies of mass composition of cosmic rays in the energy range 10 15 -10 17 eV. * Registration of cosmic ray intensity variation correlated with solar activity. Theoretical and experimental studies of Extensive Air Shower properties are performed mostly based on the results obtained by the Lodz Extensive Air Shower Array. We have noticed unexplainable delayed signals registered about 500-900 microseconds after the main EAS pulse. We prepared hardware for further experimental study of this effect. Continuous registrations of 5 GeV muon flux with the underground muon telescope have been carried on during 2001. We detected several changes of muon intensity correlated with Forbush decreases registered at lower energies. We have also started registration of the muon counting rate in on-surface scintillation detectors. These measurements will be included to the analysis of the disturbed energy spectrum of primary cosmic rays and its dependence on interplanetary disturbances related to solar activity. In construction and data interpretation of cosmic ray experiments the Lodz group collaborates with many foreign institutes and laboratories: Forschungszentrum in Karlsruhe (Germany), College de France, Institute for Nuclear Studies of the Russian Academy of Sciences, Uppsala University (Sweden) and DESY (Germany). We have prepared a project of large air shower array for studies of cosmic rays up to 10 20 eV. Detectors would be placed on the roofs of high

Muon reconstruction performance using cosmic rays in CMS

CERN Document Server

Calderon, Alicia

2009-01-01

After the incident with the Large Hadron Collider (LHC) in September 2008, the Compact Muon Solenoid (CMS) collaboration invested a considerable effort in further refining the understanding of the detector using cosmic muon data. About 300 million cosmic events were recorded with the CMS detector fully operational and the central solenoid switched on at the nominal value of 3.8 Tesla. The resulting data set provides ample statistics to study in great detail the detector performance and allows to analyze properties of cosmic rays. We present recent results on detector performance from the cosmic muon analysis activities and compare cosmic data to dedicated cosmic Monte Carlo samples. These results demonstrate the readiness of the CMS detector to do physics analysis with muons, and the study of cosmic muon properties provides interesting links to astrophysics.

Rates and patterns of molecular evolution in freshwater versus terrestrial insects.

Science.gov (United States)

Mitterboeck, T Fatima; Fu, Jinzhong; Adamowicz, Sarah J

2016-11-01

Insect lineages have crossed between terrestrial and aquatic habitats many times, for both immature and adult life stages. We explore patterns in molecular evolutionary rates between 42 sister pairs of related terrestrial and freshwater insect clades using publicly available protein-coding DNA sequence data from the orders Coleoptera, Diptera, Lepidoptera, Hemiptera, Mecoptera, Trichoptera, and Neuroptera. We furthermore test for habitat-associated convergent molecular evolution in the cytochrome c oxidase subunit I (COI) gene in general and at a particular amino acid site previously reported to exhibit habitat-linked convergence within an aquatic beetle group. While ratios of nonsynonymous-to-synonymous substitutions across available loci were higher in terrestrial than freshwater-associated taxa in 26 of 42 lineage pairs, a stronger trend was observed (20 of 31, p binomial = 0.15, p Wilcoxon = 0.017) when examining only terrestrial-aquatic pairs including fully aquatic taxa. We did not observe any widespread changes at particular amino acid sites in COI associated with habitat shifts, although there may be general differences in selection regime linked to habitat.

COSMIC-RAY TRANSPORT AND ANISOTROPIES

Energy Technology Data Exchange (ETDEWEB)

Biermann, Peter L. [MPI for Radioastronomy, Auf dem Huegel 69, D-53121 Bonn (Germany); Becker Tjus, Julia; Mandelartz, Matthias [Ruhr-Universitaet Bochum, Fakultaet fuer Physik and Astronomie, Theoretische Physik I, D-44780 Bochum (Germany); Seo, Eun-Suk [Department of Physics, University of Maryland, College Park, MD 20742 (United States)

2013-05-10

We show that the large-scale cosmic-ray anisotropy at {approx}10 TeV can be explained by a modified Compton-Getting effect in the magnetized flow field of old supernova remnants. Cosmic rays arrive isotropically to the flow field and are then carried along with the flow to produce a large-scale anisotropy in the arrival direction. This approach suggests an optimum energy scale for detecting the anisotropy. Two key assumptions are that propagation is based on turbulence following a Kolmogorov law and that cosmic-ray interactions are dominated by transport via cosmic-ray-excited magnetic irregularities through the stellar wind of an exploding star and its shock shell. A prediction is that the amplitude is smaller at lower energies due to incomplete sampling of the velocity field and also smaller at larger energies due to smearing.

Determination of the spallogenic radionuclides 26Al and 53Mn in Antartic meteorites with respect to cosmic ray exposure and terrestrial ages

International Nuclear Information System (INIS)

Herpers, U.; Sarafin, R.

1987-01-01

The spallogenic radionuclides 26 Al (T=7.18x10 5 a) and 53 Mn (T=3.8x10 6 a) were determined in 11 ordinary chondrites and 7 achondrites from Antarctica by nondestructive coincidence counting techniques and radiochemical neutron activation analysis. The results are discussed with respect to exposure ages, terrestrial residence times and possible genetic relationships of the meteorites investigated. The high terrestrial ages of some specimens (up to 800 000 years) are of importance for the study of the ice flow in Antarctica. (author)

High energy physics in cosmic rays

Energy Technology Data Exchange (ETDEWEB)

Jones, Lawrence W. [University of Michigan, Ann Arbor, Michigan (United States)

2013-02-07

In the first half-century of cosmic ray physics, the primary research focus was on elementary particles; the positron, pi-mesons, mu-mesons, and hyperons were discovered in cosmic rays. Much of this research was carried out at mountain elevations; Pic du Midi in the Pyrenees, Mt. Chacaltaya in Bolivia, and Mt. Evans/Echo Lake in Colorado, among other sites. In the 1960s, claims of the observation of free quarks, and satellite measurements of a significant rise in p-p cross sections, plus the delay in initiating accelerator construction programs for energies above 100 GeV, motivated the Michigan-Wisconsin group to undertake a serious cosmic ray program at Echo Lake. Subsequently, with the succession of higher energy accelerators and colliders at CERN and Fermilab, cosmic ray research has increasingly focused on cosmology and astrophysics, although some groups continue to study cosmic ray particle interactions in emulsion chambers.

Cosmic rays, clouds and climate

Energy Technology Data Exchange (ETDEWEB)

Svensmark, Henrik [Danish Space Research Institute, Juliane Maries Vej 30, DK-2100 Copenhagen (Denmark)

2007-07-01

Changes in the intensity of galactic cosmic rays seems alter the Earth's cloudiness. A recent experiment has shown how electrons liberated by cosmic rays assist in making aerosols, the building blocks of cloud condensation nuclei, while anomalous climatic trends in Antarctica confirm the role of clouds in helping to drive climate change. Variations in the cosmic-ray influx due to solar magnetic activity account well for climatic fluctuations on decadal, centennial and millennial timescales. Over longer intervals, the changing galactic environment of the Solar System has had dramatic consequences, including Snowball Earth episodes.

High-energy cosmic-ray acceleration

CERN Document Server

Bustamante, M; de Paula, W; Duarte Chavez, J A; Gago, A M; Hakobyan, H; Jez, P; Monroy Montañez, J A; Ortiz Velasquez, A; Padilla Cabal, F; Pino Rozas, M; Rodriguez Patarroyo, D J; Romeo, G L; Saldaña-Salazar , U J; Velasquez, M; von Steinkirch, M

2010-01-01

We briefly review the basics of ultrahigh-energy cosmic-ray acceleration. The Hillas criterion is introduced as a geometrical criterion that must be fulfilled by potential acceleration sites, and energy losses are taken into account in order to obtain a more realistic scenario. The different available acceleration mechanisms are presented, with special emphasis on Fermi shock acceleration and its prediction of a power-law cosmic-ray energy spectrum. We conclude that first-order Fermi acceleration, though not entirely satisfactory, is the most promising mechanism for explaining the ultra-high-energy cosmic-ray flux.

Department of Cosmic Ray Physics - Overview

International Nuclear Information System (INIS)

Szabelski, J.

2008-01-01

Full text: The Department of Cosmic Ray Physics in Lodz is involved in basic research in the high energy Cosmic Ray field. Cosmic Rays are energetic particles from outside the Solar System. Most of the studies of Cosmic Rays address fundamental problems: · the nature of the physical and astrophysical processes responsible for high energies of particles · an estimation of the astrophysical conditions at the acceleration sites and/or search for sources of Cosmic Rays, · properties of high energy particle interactions at very high energies. Some Cosmic Ray studies might have practical (commercial) implications, e.g. · '' cosmic weather '' forecast - predictions of geomagnetic disturbances related to Solar activity changes (due to large Solar Flares / events of Coronal Mass Ejection); these are important for large electricity networks, gas pipes, radio-wave connections, space missions and satellite experiments. Presentation of Cosmic Ray registration to high school students becomes a popular way to introduce particle physics detectors and elementary particle detection techniques to young people. We organize in Lodz several workshops on particle physics for high school students. This is a part of European activity: EPPOG's Masterclass - Hands on CERN. Energetic Cosmic Ray particles produce cascades of particles in the atmosphere, called Extensive Air Showers (EAS). Registering EAS and their properties is the main way of experimental studies of very high energy Cosmic Rays. In Lodz Department we run Extensive Air Shower array where EAS are continuously being registered. We concentrate on the studies of detection of neutrons correlated with EAS and interpretation of this phenomenon. In 2004 we started realisation of the Roland Maze Project, the network of EAS detectors placed on the roofs of high schools in Lodz. We received funds from the City of Lodz budget to make a pilot project and equip 10 high schools, each with four 1m 2 detectors and GPS. The network is

Possibilities for the detection of microbial life on extrasolar planets.

Science.gov (United States)

Knacke, Roger F

2003-01-01

We consider possibilities for the remote detection of microbial life on extrasolar planets. The Darwin/Terrestrial Planet Finder (TPF) telescope concepts for observations of terrestrial planets focus on indirect searches for life through the detection of atmospheric gases related to life processes. Direct detection of extraterrestrial life may also be possible through well-designed searches for microbial life forms. Satellites in Earth orbit routinely monitor colonies of terrestrial algae in oceans and lakes by analysis of reflected ocean light in the visible region of the spectrum. These remote sensing techniques suggest strategies for extrasolar searches for signatures of chlorophylls and related photosynthetic compounds associated with life. However, identification of such life-related compounds on extrasolar planets would require observations through strong, interfering absorptions and scattering radiances from the remote atmospheres and landmasses. Techniques for removal of interfering radiances have been extensively developed for remote sensing from Earth orbit. Comparable techniques would have to be developed for extrasolar planet observations also, but doing so would be challenging for a remote planet. Darwin/TPF coronagraph concepts operating in the visible seem to be best suited for searches for extrasolar microbial life forms with instruments that can be projected for the 2010-2020 decades, although resolution and signal-to-noise ratio constraints severely limit detection possibilities on terrestrial-type planets. The generation of telescopes with large apertures and extremely high spatial resolutions that will follow Darwin/TPF could offer striking possibilities for the direct detection of extrasolar microbial life.

Cosmic rays on earth

International Nuclear Information System (INIS)

Allkofer, O.C.; Grieder, P.K.F.

1984-01-01

A data collection is presented that covers cosmic rays on earth. Included are all relevant data on flux and intensity measurements, energy spectra, and related data of all primary and secondary components of the cosmic radiation at all levels in the atmosphere, at sea level and underground. In those cases where no useful experimental data have been available, theoretical predictions were substituted. (GSCH)

High-energy cosmic rays

CERN Document Server

Cronin, James Watson

1996-01-01

Recently two cosmic rays with energy in excess of 2 1020 eV have been recorded. These are some 108 times more energetic than the protons produced by accelerators on earth. There is no credible understanding of the mechanism of acceleration by known a Because of the short mean free path in the cosmic background radiation they must come from nearby distances on a cosmological scale (< 50 Mpc). Their magnetic rigidity suggests that they should point to their source. Lectures will cover the present available data on the highest energy cosmic rays, their detection, possible acceleration mechanisms, their propagation in the galaxy and in extra galactic space and design of new detectors where simulations of air show ers play an important role.

Empirical model for the Earth's cosmic ray shadow at 400 KM: prohibited cosmic ray access

International Nuclear Information System (INIS)

Humble, J.E.; Smart, D.F.; Shea, M.A.

1985-01-01

The possibility of constructing a unit sphere of access that describes the cosmic radiation allowed to an Earth-orbiting spacecraft is discussed. It is found that it is possible to model the occluded portion of the cosmic ray sphere of access as a circular projection with a diameter bounded by the satellite-Earth horizon. Maintaining tangency at the eastern edge of the spacecraft-Earth horizon, this optically occluded area is projected downward by an angle beta which is a function of the magnetic field inclination and cosmic ray arrival direction. This projected plane, corresponding to the forbidden area of cosmic ray access, is bounded by the spacecraft-Earth horizon in easterly directions, and is rotated around the vertical axis by an angle alpha from the eastern direction, where the angle alpha is a function of the offset dipole latitude of the spacecraft

Cosmic ray physics with ACORDE at LHC

Energy Technology Data Exchange (ETDEWEB)

Pagliarone, C [Universita degli Studi di Cassino and INFN Pisa, Largo B. Pontecorvo, 3 - Pisa (Italy); Fernandez-Tellez, A [Benemerita Universidad Autonoma de Puebla (BUAP), Puebla (Mexico)], E-mail: pagliarone@fnal.gov

2008-05-15

The use of large underground high-energy physics experiments, for comic ray studies, have been used, in the past, at CERN, in order to measure, precisely, the inclusive cosmic ray flux in the energy range from 2{center_dot}10{sup 10} to 2{center_dot} 10{sup 12} eV. ACORDE, ALICE Cosmic Rays DEtector, will act as Level 0 cosmic ray trigger and, together with other ALICE apparatus, will provide precise information on cosmic rays with primary energies around 10{sup 15} to 10{sup 17} eV. This paper reviews the main detector features, the present status, commissioning and integration with other apparatus. Finally, we discuss the ACORDE-ALICE cosmic ray physics program.

Geology and Habitability of Terrestrial Planets

CERN Document Server

Fishbaugh, Kathryn E; Raulin, François; Marais, David J; Korablev, Oleg

2007-01-01

Given the fundamental importance of and universal interest in whether extraterrestrial life has developed or could eventually develop in our solar system and beyond, it is vital that an examination of planetary habitability goes beyond simple assumptions such as, "Where there is water, there is life." This book has resulted from a workshop at the International Space Science Institute (ISSI) in Bern, Switzerland (5-9 September 2005) that brought together planetary geologists, geophysicists, atmospheric scientists, and biologists to discuss the multi-faceted problem of how the habitability of a planet co-evolves with the geology of the surface and interior, the atmosphere, and the magnetosphere. Each of the six chapters has been written by authors with a range of expertise so that each chapter is itself multi-disciplinary, comprehensive, and accessible to scientists in all disciplines. These chapters delve into what life needs to exist and ultimately to thrive, the early environments of the young terrestrial pl...

Cosmic ray investigations

International Nuclear Information System (INIS)

Zatsepin, Georgii T; Roganova, Tat'yana M

2009-01-01

The history of cosmic ray research at the Lebedev Institute beginning with the first work and continuing up to now is reviewed. The milestones and main avenues of research are outlined. Pioneering studies on the nuclear cascade process in extensive air showers, investigations of the Vavilov-Cherenkov radiation, and some work on the origin of cosmic rays are discussed. Recent data on ultrahigh-energy particle detection at the Pierre Auger Observatory and the High Resolution Fly's Eye (HiRes) experiments are presented. (conferences and symposia)

Cosmic Sum Rules

DEFF Research Database (Denmark)

T. Frandsen, Mads; Masina, Isabella; Sannino, Francesco

2011-01-01

We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays and show how it can be used to predict the positron fraction at energies not yet explored by current experiments and to constrain specific models.......We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays and show how it can be used to predict the positron fraction at energies not yet explored by current experiments and to constrain specific models....

Heterotic cosmic strings

International Nuclear Information System (INIS)

Becker, Katrin; Becker, Melanie; Krause, Axel

2006-01-01

We show that all three conditions for the cosmological relevance of heterotic cosmic strings, the right tension, stability and a production mechanism at the end of inflation, can be met in the strongly coupled M-theory regime. Whereas cosmic strings generated from weakly coupled heterotic strings have the well-known problems posed by Witten in 1985, we show that strings arising from M5-branes wrapped around 4-cycles (divisors) of a Calabi-Yau in heterotic M-theory compactifications solve these problems in an elegant fashion

Colony contact contributes to the diversity of gut bacteria in bumblebees (Bombus terrestris)

Institute of Scientific and Technical Information of China (English)

Annelies Billiet; Ivan Meeus; Filip Van Nieuwerburgh; Dieter Deforce; Felix W(a)ckers; Guy Smagghe

2017-01-01

Social bees,like honeybees and bumblebees,have a close contact with nest mates of different developmental stages and generations.This could enhance bacterial transfer between nest mates and offers opportunities for direct transfer of symbionts from one generation to the next,resulting in a stable host specific gut microbiota.Gut symbionts of honeybees and bumblebees have been suggested to contribute in digestion and protection against parasites and pathogens.Here we studied the impact of contact with the bumblebee colony on the colonization potential of the bacterial families (i.e.,Neisseriaceae,Orbaceae,Lactobacillaceae and Bifidobacteriaceae) occurring in the gut of adult bumblebees (Bombus terrestris).Bacterial profiles of the gut microbiota of B.terrestris were determined based on the hypervariable V4 region of the 16S rRNA using paired-end Illumina sequencing.In our experiments,we created different groups in which we gradually reduced the contact with nest mates and hive material.We made 3 observations:(i) reducing the contact between the colony and the bumblebee during adult life resulted in a significant drop in the relative abundance of Lactobacillus bombicola and Lactobacillus bombi;(ii) Bifidobacteriaceae required contact with nest mates to colonize the gut of B.terrestris and a significant lower bacterial diversity was observed in bumblebees that were completely excluded from colony contact during the adult life;(iii) Snodgrassella and Gilliamella were able to colonize the gut of the adult bumblebee without any direct contact with nest mates in the adult life stage.These results indicate the impact of the colony life on the diversity of the characteristic bumblebee gut bacteria.

Large angle cosmic microwave background fluctuations from cosmic strings with a cosmological constant

International Nuclear Information System (INIS)

Landriau, M.; Shellard, E.P.S.

2004-01-01

In this paper, we present results for large-angle cosmic microwave background anisotropies generated from high resolution simulations of cosmic string networks in a range of flat Friedmann-Robertson-Walker universes with a cosmological constant. Using an ensemble of all-sky maps, we compare with the Cosmic Background Explorer data to infer a normalization (or upper bound) on the string linear energy density μ. For a flat matter-dominated model (Ω M =1) we find Gμ/c 2 ≅0.7x10 -6 , which is lower than previous constraints probably because of the more accurate inclusion of string small-scale structure. For a cosmological constant within an observationally acceptable range, we find a relatively weak dependence with Gμ/c 2 less than 10% higher

Broken symmetries at the origin of matter, at the origin of life and at the origin of culture

Energy Technology Data Exchange (ETDEWEB)

Klinken, J. van [Kernfysisch Versneller Instituut, University of Groningen, Groningen (Netherlands)

1998-01-01

In earliest cosmic history the universe started with matter and not with antimatter. Shortly after the beginning the electroweak interaction - prominent in nuclear {beta} decay - acted as a left-hander. Much later, in pre biotic evolution, optically left-handed amino acids determined the unique signature of following terrestrial organic life. Again ae- ons later, homo sapiens appears as predominantly right handed and creates cultures with many broken symmetries. Along these pathways of history it was essential that choices were made - left or right, matter or antimatter - but on several instances it seemed less relevant which choice were made. We think that biochirality occurred by global chance; perhaps by local necessity, but without causal links to the PCT theorem. In other cases - e.g. the standardization to right-handed screws - the choice will have been made by causal necessity. (author) 14 refs, 8 figs, 1 tab

Cosmic radiation exposure to airline flight passenger

International Nuclear Information System (INIS)

Momose, Mitsuhiro

2000-01-01

At the high altitudes, airline flight passengers can be exposed to some levels of cosmic radiation. The purpose of this study was to quantify this radiation exposure. Cosmic radiation was measured during 5 flights using a personal dosimeter (PDM-102, Aloka). Cosmic radiation equivalent dose rates ranged from 0.7 to 1.43 microsieverts per hour, the average rate was 1.08. For the passenger who travels only occasionally, the cosmic radiation levels are well below occupational limits, and the risks are extremely small. (author)

Cosmic radiation exposure to airline flight passenger

Energy Technology Data Exchange (ETDEWEB)

Momose, Mitsuhiro [Shinshu Univ., Matsumoto, Nagano (Japan). School of Medicine

2000-08-01

At the high altitudes, airline flight passengers can be exposed to some levels of cosmic radiation. The purpose of this study was to quantify this radiation exposure. Cosmic radiation was measured during 5 flights using a personal dosimeter (PDM-102, Aloka). Cosmic radiation equivalent dose rates ranged from 0.7 to 1.43 microsieverts per hour, the average rate was 1.08. For the passenger who travels only occasionally, the cosmic radiation levels are well below occupational limits, and the risks are extremely small. (author)

Cosmic ray production curves below reworking zones

International Nuclear Information System (INIS)

Blanford, G.E.

1980-01-01

A method is presented for calculating cosmic ray production profiles below reworking zones. The method uses an input reworking depth determined from data such as signatures in the depth profile of ferromagnetic resonance intensity and input cosmic ray production profiles for an undisturbed surface. Reworking histories are simulated using Monte Carlo techniques, and depth profiles are used to determine cosmic ray exposure age limits with a specified probability. It is shown that the track density profiles predict cosmic ray exposure ages in lunar cores that are consistent with values determined by other methods. Results applied to neutron fluence and spallation rare gases eliminate the use of reworking depth as an adjustable parameter and give cosmic ray exposure ages that are compatible with each other

Department of Cosmic Ray Physics - Overview

International Nuclear Information System (INIS)

Szabelski, J.

2007-01-01

The Department of Cosmic Ray Physics in Lodz is involved in basic research in the high energy Cosmic Ray field. Cosmic Rays are energetic particles from outside the Solar System. The energy spectrum (power law energy dependence) suggests non-thermal origin of these particles. Most of the studies of Cosmic Rays address fundamental problems: · the nature of the physical and astrophysical processes responsible for high energies of particles (up to about 1020 eV/particle), · an estimation of the astrophysical conditions at the acceleration sites and/or search for sources of Cosmic Rays, · properties of high energy particle interactions at very high energies (nuclear interactions at energies exceeding energy available in the laboratories). Some Cosmic Ray studies might have practical (commercial) implications, e.g.: · '' cosmic weather '' forecast - predictions of geomagnetic disturbances related to Solar activity changes (due to large Solar Flares / events of Coronal Mass Ejection); these are important for large electricity networks, gas pipes, radio-wave connections, space missions and satellite experiments. Presentation of Cosmic Ray registration to high school students becomes a popular way to introduce particle physics detectors and elementary particle detection techniques to young people. We organize in Lodz several workshops on particle physics for high school students. This is a part of European activity: Masterclass - Hands on CERN. Energetic Cosmic Ray particles produce cascades of particles in the atmosphere, called Extensive Air Showers (EAS). Registering EAS and their properties is the main way of experimental studies of very high energy Cosmic Rays. In Lodz Department we run Extensive Air Shower array where EAS are continuously being registered. We concentrate on the studies of detection of neutrons correlated with EAS and interpretation of this phenomenon. Back in 2004 we started realisation of the Roland Maze Project, the network of EAS detectors

Production and localization of cellulases and. beta. -glucosidase from the thermophilic fungus Thielavia terrestris

Energy Technology Data Exchange (ETDEWEB)

Breuil, C; Wojtczak, G; Saddler, J N

1986-01-01

The enzyme production and localization of Thielavia terrestris strains C464 and NRRL 8126 were compared to determine their optimum temperature and pH for cellulase activity. High levels of intracellular ..beta..-glucosidase activity were detected in the former strain. The intracellular ..beta..-glucosidase of both strains were more thermostable than the extra-cellular enzyme; the half life of T. terrestris (C464) endoglucanase activity at 60 degrees C was greater than 96 hours. 12 references.

Our cosmic future : humanity's fate in the universe

Science.gov (United States)

Prantzos, Nikos

2000-04-01

What is humankind's ultimate fate and destiny in the Universe? Can human life and intelligence go on forever? This captivating and unparalleled book explores the future of the human race in the Universe, for centuries, millennia, and eons to come. Nikos Prantzos, distinguished astrophysicist and popular science writer, focuses not on what will be done, but on what could be done in light of our current knowledge and the speculations of eminent scientists. While he employs many concepts from physics, Prantzos also provides historical accounts of such ideas as terraforming, asteroid mining, interstellar travel, astroengineering, and eschatology, discussing their philosophical and social implications. Moreover, he uses the work of well known science and science-fiction writers--including Verne, Wells, Clarke, Tsiolkovsky, and Dyson--to illustrate many possibilities and concepts. Our Cosmic Future offers compelling answers to such intriguing questions as: Should we return to the Moon and eventually colonize Mars and other planets in our solar system? Why haven't we encountered an extraterrestrial civilization up to this time in our history? How can we avoid various cosmic threats, such as asteroid collisions and supernova explosions? Could we escape the remote, yet certain, death of the Sun? What will eventually happen to stars, our Galaxy, distant galaxies, and the Universe itself? With its artful blend of historical, scientific accounts and themes from classic works of science fiction, Our Cosmic Future is a spellbinding work that will enchant all readers interested in space travel and colonization, cosmology, and humankind's future prospects in the Cosmos.

A Shifting Shield Provides Protection Against Cosmic Rays

Science.gov (United States)

Kohler, Susanna

2017-12-01

The Sun plays an important role in protecting us from cosmic rays, energetic particles that pelt us from outside our solar system. But can we predict when and how it will provide the most protection, and use this to minimize the damage to both pilotedand roboticspace missions?The Challenge of Cosmic RaysSpacecraft outside of Earths atmosphere and magnetic field are at risk of damage from cosmic rays. [ESA]Galactic cosmic rays are high-energy, charged particles that originate from astrophysical processes like supernovae or even distant active galactic nuclei outside of our solar system.One reason to care about the cosmic rays arriving near Earth is because these particles can provide a significant challenge for space missions traveling above Earths protective atmosphere and magnetic field. Since impacts from cosmic rays can damage human DNA, this risk poses a major barrier to plans for interplanetary travel by crewed spacecraft. And roboticmissions arent safe either: cosmic rays can flip bits, wreaking havoc on spacecraft electronics as well.The magnetic field carried by the solar wind provides a protective shield, deflecting galactic cosmic rays from our solar system. [Walt Feimer/NASA GSFCs Conceptual Image Lab]Shielded by the SunConveniently, we do have some broader protection against galactic cosmic rays: a built-in shield provided by the Sun. The interplanetary magnetic field, which is embedded in the solar wind, deflects low-energy cosmic rays from us at the outer reaches of our solar system, decreasing the flux of these cosmic rays that reach us at Earth.This shield, however, isnt stationary; instead, it moves and changes as the strength and direction of the solar wind moves and changes. This results in a much lower cosmic-ray flux at Earth when solar activity is high i.e., at the peak of the 11-year solar cycle than when solar activity is low. This visible change in local cosmic-ray flux with solar activity is known as solar modulation of the cosmic ray flux

Testing the weak gravity-cosmic censorship connection

Science.gov (United States)

Crisford, Toby; Horowitz, Gary T.; Santos, Jorge E.

2018-03-01

A surprising connection between the weak gravity conjecture and cosmic censorship has recently been proposed. In particular, it was argued that a promising class of counterexamples to cosmic censorship in four-dimensional Einstein-Maxwell-Λ theory would be removed if charged particles (with sufficient charge) were present. We test this idea and find that indeed if the weak gravity conjecture is true, one cannot violate cosmic censorship this way. Remarkably, the minimum value of charge required to preserve cosmic censorship appears to agree precisely with that proposed by the weak gravity conjecture.

Terrestrial pesticide exposure of amphibians: an underestimated cause of global decline?

Science.gov (United States)

Brühl, Carsten A; Schmidt, Thomas; Pieper, Silvia; Alscher, Annika

2013-01-01

Amphibians, a class of animals in global decline, are present in agricultural landscapes characterized by agrochemical inputs. Effects of pesticides on terrestrial life stages of amphibians such as juvenile and adult frogs, toads and newts are little understood and a specific risk assessment for pesticide exposure, mandatory for other vertebrate groups, is currently not conducted. We studied the effects of seven pesticide products on juvenile European common frogs (Rana temporaria) in an agricultural overspray scenario. Mortality ranged from 100% after one hour to 40% after seven days at the recommended label rate of currently registered products. The demonstrated toxicity is alarming and a large-scale negative effect of terrestrial pesticide exposure on amphibian populations seems likely. Terrestrial pesticide exposure might be underestimated as a driver of their decline calling for more attention in conservation efforts and the risk assessment procedures in place do not protect this vanishing animal group.

Cosmic rays at ultra high energies (Neutrinos.)

International Nuclear Information System (INIS)

Ahlers, M.; Ringwald, A.; Tu, H.

2005-06-01

Resonant photopion production with the cosmic microwave background predicts a suppression of extragalactic protons above the famous Greisen-Zatsepin-Kuzmin cutoff at about E GZK ∼ 5 x 10 10 GeV. Current cosmic ray data measured by the AGASA and HiRes Collaborations do not unambiguously confirm the GZK cutoff and leave a window for speculations about the origin and chemical composition of the highest energy cosmic rays. In this work we analyze the possibility of strongly interacting neutrino primaries and derive model-independent quantitative requirements on the neutrino-nucleon inelastic cross section for a viable explanation of the cosmic ray data. Search results on weakly interacting cosmic particles from the AGASA and RICE experiments are taken into account simultaneously. Using a flexible parameterization of the inelastic neutrino-nucleon cross section we find that a combined fit of the data does not favor the Standard Model neutrino-nucleon inelastic cross section, but requires, at 90% confidence level, a steep increase within one energy decade around E GZK by four orders of magnitude. We illustrate such an enhancement within some extensions of the Standard Model. The impact of new cosmic ray data or cosmic neutrino search results on this scenario, notably from the Pierre Auger Observatory soon, can be immediately evaluated within our approach. (orig.)

Relativistic transport theory for cosmic-rays

International Nuclear Information System (INIS)

Webb, G.M.

1985-01-01

Various aspects of the transport of cosmic-rays in a relativistically moving magnetized plasma supporting a spectrum of hydromagnetic waves that scatter the cosmic-rays are presented. A local Lorentz frame moving with the waves or turbulence scattering the cosmic-rays is used to specify the individual particle momentum. The comoving frame is in general a noninertial frame in which the observer's volume element is expanding and shearing, geometric energy change terms appear in the cosmic-ray transport equation which consist of the relativistic generalization of the adiabatic deceleration term and a further term involving the acceleration vector of the scatterers. A relativistic version of the pitch angle evolution equation, including the effects of adiabatic focussing, pitch angle scattering, and energy changes is presented

Cosmic Rays in Intermittent Magnetic Fields

International Nuclear Information System (INIS)

Shukurov, Anvar; Seta, Amit; Bushby, Paul J.; Wood, Toby S.; Snodin, Andrew P.

2017-01-01

The propagation of cosmic rays in turbulent magnetic fields is a diffusive process driven by the scattering of the charged particles by random magnetic fluctuations. Such fields are usually highly intermittent, consisting of intense magnetic filaments and ribbons surrounded by weaker, unstructured fluctuations. Studies of cosmic-ray propagation have largely overlooked intermittency, instead adopting Gaussian random magnetic fields. Using test particle simulations, we calculate cosmic-ray diffusivity in intermittent, dynamo-generated magnetic fields. The results are compared with those obtained from non-intermittent magnetic fields having identical power spectra. The presence of magnetic intermittency significantly enhances cosmic-ray diffusion over a wide range of particle energies. We demonstrate that the results can be interpreted in terms of a correlated random walk.

Cosmic Rays in Intermittent Magnetic Fields

Energy Technology Data Exchange (ETDEWEB)

Shukurov, Anvar; Seta, Amit; Bushby, Paul J.; Wood, Toby S. [School of Mathematics and Statistics, Newcastle University, Newcastle Upon Tyne NE1 7RU (United Kingdom); Snodin, Andrew P., E-mail: a.seta1@ncl.ac.uk, E-mail: amitseta90@gmail.com [Department of Mathematics, Faculty of Applied Science, King Mongkut’s University of Technology North Bangkok, Bangkok 10800 (Thailand)

2017-04-10

The propagation of cosmic rays in turbulent magnetic fields is a diffusive process driven by the scattering of the charged particles by random magnetic fluctuations. Such fields are usually highly intermittent, consisting of intense magnetic filaments and ribbons surrounded by weaker, unstructured fluctuations. Studies of cosmic-ray propagation have largely overlooked intermittency, instead adopting Gaussian random magnetic fields. Using test particle simulations, we calculate cosmic-ray diffusivity in intermittent, dynamo-generated magnetic fields. The results are compared with those obtained from non-intermittent magnetic fields having identical power spectra. The presence of magnetic intermittency significantly enhances cosmic-ray diffusion over a wide range of particle energies. We demonstrate that the results can be interpreted in terms of a correlated random walk.

Semianalytic calculation of cosmic microwave background anisotropies from wiggly and superconducting cosmic strings

Science.gov (United States)

Rybak, I. Yu.; Avgoustidis, A.; Martins, C. J. A. P.

2017-11-01

We study how the presence of world-sheet currents affects the evolution of cosmic string networks, and their impact on predictions for the cosmic microwave background (CMB) anisotropies generated by these networks. We provide a general description of string networks with currents and explicitly investigate in detail two physically motivated examples: wiggly and superconducting cosmic string networks. By using a modified version of the CMBact code, we show quantitatively how the relevant network parameters in both of these cases influence the predicted CMB signal. Our analysis suggests that previous studies have overestimated the amplitude of the anisotropies for wiggly strings. For superconducting strings the amplitude of the anisotropies depends on parameters which presently are not well known—but which can be measured in future high-resolution numerical simulations.

Contaminant exposure in terrestrial vertebrates

International Nuclear Information System (INIS)

Smith, Philip N.; Cobb, George P.; Godard-Codding, Celine; Hoff, Dale; McMurry, Scott T.; Rainwater, Thomas R.; Reynolds, Kevin D.

2007-01-01

Here we review mechanisms and factors influencing contaminant exposure among terrestrial vertebrate wildlife. There exists a complex mixture of biotic and abiotic factors that dictate potential for contaminant exposure among terrestrial and semi-terrestrial vertebrates. Chemical fate and transport in the environment determine contaminant bioaccessibility. Species-specific natural history characteristics and behavioral traits then play significant roles in the likelihood that exposure pathways, from source to receptor, are complete. Detailed knowledge of natural history traits of receptors considered in conjunction with the knowledge of contaminant behavior and distribution on a site are critical when assessing and quantifying exposure. We review limitations in our understanding of elements of exposure and the unique aspects of exposure associated with terrestrial and semi-terrestrial taxa. We provide insight on taxa-specific traits that contribute, or limit exposure to, transport phenomenon that influence exposure throughout terrestrial systems, novel contaminants, bioavailability, exposure data analysis, and uncertainty associated with exposure in wildlife risk assessments. Lastly, we identify areas related to exposure among terrestrial and semi-terrestrial organisms that warrant additional research. - Both biotic and abiotic factors determine chemical exposure for terrestrial vertebrates

Department of Cosmic Ray Physics - Overview

International Nuclear Information System (INIS)

Szabelski, J

2005-01-01

Full text: The Department of Cosmic Ray Physics in Lodz is involved in basic research in the high energy Cosmic Ray field. Cosmic Rays are energetic particles from outside the Solar System. The energy spectrum (power law energy dependence) suggests a non-thermal origin of these particles. Most studies of Cosmic Rays address fundamental problems: - the nature of the physical and astrophysical processes responsible for high energies of particles (up to about 10 20 eV/particle), - estimation of the astrophysical conditions at the acceleration sites and/or search for sources of Cosmic Rays, - properties of high energy particle interactions at very high energies (nuclear interactions at energies exceeding energy available in laboratories). - Some Cosmic Ray studies might have practical (commercial) implications, e.g. - ''cosmic weather'' forecast - predictions of geomagnetic disturbances related to Solar activity changes (due to large Solar Flares / events of Coronal Mass Ejection); these are important for large electricity networks, gas pipes, radio-wave connections, space missions and satellite experiments. Presentation of Cosmic Ray registration to high school students is a popular way to introduce particle physics detectors and elementary particle detection techniques to young people. Energetic Cosmic Ray particles produce cascades of particles in the atmosphere, called Extensive Air Showers (EAS). Registering the EAS and their properties is the main way of experimental studies of very high energy Cosmic Rays. In our Lodz Department we run an Extensive Air Shower array where EAS are continuously being registered. We concentrate on the studies of detection of neutrons correlated with EAS and interpretation of this phenomenon. In 2004 we started realisation of the Roland Maze Project, the network of EAS detectors placed on the roofs of high schools in Lodz. We received funds from the City of Lodz's budget to make a pilot project and equip 10 high schools, each with

Department of Cosmic Ray Physics - Overview

International Nuclear Information System (INIS)

Szabelski, J.

2009-01-01

Full text: The Department of Cosmic Ray Physics in Lodz is involved in basic research in the high-energy Cosmic Ray field. Cosmic Rays are energetic particles from outside the Solar System. Most of the studies of Cosmic Rays address fundamental problems: - the nature of the physical and astrophysical processes responsible for the high energies of the particles - an estimation of the astrophysical conditions at the acceleration sites and/or the search for sources of Cosmic Rays, - properties of high-energy particle interactions at very high energies. Some Cosmic Ray studies might have practical (commercial) implications, e.g. - '' cosmic weather '' forecasting - predictions of geomagnetic disturbances related to Solar activity changes (due to large Solar Flares/Coronal Mass Ejection events); these are important for large electricity networks, gas pipelines, radio-wave connections, space missions and satellite experiments. Presentation of Cosmic Ray registration to high school students has become a popular way to introduce particle physics detectors and elementary particle detection techniques to young people. We organize in Lodz and Poznan workshops on particle physics for high school students. This is a part of the European activity: EPPOG's Masterclass - Hands on CERN. Energetic Cosmic Ray particles produce cascades of particles in the atmosphere, called Extensive Air Showers (EAS). Registering EAS and their properties is the main way of experimentally study's very high energy Cosmic Rays. Locally in Lodz we concentrate on methodological studies of the detection of neutrons correlated with EAS and the interpretation of this phenomenon. We have also performed two series of neutron background measurements in the deep underground Gran Sasso Laboratory in Italy (within the ILIAS-TA Project). In 2004, we began the Roland Maze Project, a network of EAS detectors placed on the roofs of high schools in Lodz. The pilot project is to equip 10 high schools, each with four 1m

Cosmic-ray anisotropy studies with IceCube

Science.gov (United States)

McNally, Frank

2014-03-01

The IceCube neutrino observatory detects tens of billions of energetic muons per year produced by cosmic-ray interactions with the atmosphere. The size of this sample has allowed IceCube to observe a significant anisotropy in arrival direction for cosmic rays with median energies between 20 and 400 TeV. This anisotropy is characterized by a large scale structure of per-mille amplitude accompanied by structures with smaller amplitudes and with typical angular sizes between 10° and 20°. IceTop, the surface component of IceCube, has observed a similar anisotropy in the arrival direction distribution of cosmic rays, extending the study to PeV energies. The better energy resolution of IceTop allows for additional studies of the anisotropy, for example a comparison of the energy spectrum in regions of a cosmic-ray excess or deficit to the rest of the sky. We present an update on the cosmic-ray anisotropy observed with IceCube and IceTop and the results of first studies of the energy spectrum at locations of cosmic-ray excess or deficit.

Cosmic ray investigation for the Voyager missions; energetic particle studies in the outer heliosphere - and beyond

Energy Technology Data Exchange (ETDEWEB)

Stone, E C; Vogt, R E [California Inst. of Tech., Pasadena (USA); McDonald, F B; Teegarden, B J; Trainor, J H [National Aeronautics and Space Administration, Greenbelt, Md. (USA). Goddard Space Flight Center; Jokipii, J R [Arizona Univ., Tucson (USA); Webber, W R [New Hampshire Univ., Durham (USA)

1977-12-01

A cosmic-ray detector system (CRS) has been developed for the Voyager mission which will measure the energy spectrum of electrons from approximately 3-110 MeV and the energy spectra and elemental comparison of all cosmic-ray nuclei from hydrogen through iron over an energy range from approximately 1-500 MeV.nuc. Isotopes of hydrogen through sulfur will be resolved from approximately 2-75 MeV/nuc. Studies with CRS data will provide information on the energy content, origin and acceleration process, life history, and dynamics of cosmic rays in the galaxy, and contribute to an understanding of the nucleosynthesis of elements in the cosmic-ray sources. Particular emphasis will be placed on low-energy phenomena that are expected to exist in interstellar space and are known to be present in the outer Solar System. This investigation will also add to our understanding of the transport of cosmic rays, Jovian electrons, and low-energy interplanetary particles over an extended region of interplanetary space. A major contribution to these areas of study will be the measurement of three-dimensional streaming patterns of nuclei from H through Fe and electrons over an extended energy range, with a precision that will allow determination of anisotropies down to 1%. The required combination of charge resolution, reliability and redundance has been achieved with systems consisting entirely of solid-state charged-particle detectors.

Terrestrial atmosphere, water and astrobiology

Directory of Open Access Journals (Sweden)

Coradini M.

2010-12-01

Full Text Available Primitive life, defined as a chemical system capable to transfer its molecular information via self-replication and also capable to evolve, originated about 4 billion years ago from the processing of organic molecules by liquid water. Terrestrial atmosphere played a key role in the process by allowing the permanent presence of liquid water and by participating in the production of carbon-based molecules. Water molecules exhibit specific properties mainly due to a dense network of hydrogen bonds. The carbon-based molecules were either home made in the atmosphere and/or in submarine hydrothermal systems or delivered by meteorites and micrometeorites. The search for possible places beyond the earth where the trilogy atmosphere/water/life could exist is the main objective of astrobiology. Within the Solar System, exploration missions are dedicated to Mars, Europa, Titan and the icy bodies. The discovery of several hundreds of extrasolar planets opens the quest to the whole Milky Way.

USING COSMIC MICROWAVE BACKGROUND LENSING TO CONSTRAIN THE MULTIPLICATIVE BIAS OF COSMIC SHEAR

International Nuclear Information System (INIS)

Vallinotto, Alberto

2012-01-01

Weak gravitational lensing is one of the key probes of cosmology. Cosmic shear surveys aimed at measuring the distribution of matter in the universe are currently being carried out (Pan-STARRS) or planned for the coming decade (DES, LSST, EUCLID, WFIRST). Crucial to the success of these surveys is the control of systematics. In this work, a new method to constrain one such family of systematics, known as multiplicative bias, is proposed. This method exploits the cross-correlation between weak-lensing measurements from galaxy surveys and the ones obtained from high-resolution cosmic microwave background experiments. This cross-correlation is shown to have the power to break the degeneracy between the normalization of the matter power spectrum and the multiplicative bias of cosmic shear and to be able to constrain the latter to a few percent.

A two-zone cosmic ray propagation model and its implication of the surviving fraction of radioactive cosmic ray isotopes

International Nuclear Information System (INIS)

Simon, M.; Scherzer, R.; Enge, W.

1977-01-01

In cosmic ray propagation calculations one can usually assume a homogeneous distribution of interstellar matter. The crucial astrophysical parameters in these models are: The path length distribution, the age of the cosmic ray particles and the interstellar matter density. These values are interrelated. The surviving fraction of radioactive cosmic ray isotopes is often used to determine a mean matter density of that region, where the cosmic ray particles may mainly reside. Using a Monte Carlo Propagation Program we calculated the change in the surviving fraction quantitatively assuming a region around the sources with higher matter density. (author)

Investigating the Present Day Cosmic Dust Flux at the Earth's Surface: Initial Results from the Kwajalein Micrometeorite Collection

Science.gov (United States)

Wozniakiewicz, P. J.; Bradley, J. P.; Price, M. C.; Zolensky, M. E.; Ishii, H. A.; Brownlee, D. E.; Russell, S. S.

2014-01-01

Examination of impact craters on the Long Duration Exposure Facility satellite indicate a present day micrometeoroid flux of approx. 30,000 tonnes [1 after 2]. But what portion of this material arrives at the Earth's surface as micrometeorites? Studies of available micrometeorite collections from deep sea sediments [e.g. 3], Greenland blue ice [e.g. 4] and the South Pole water well [e.g. 1] may be complicated by terrestrial weathering and, in some cases, collection bias (magnetic separation for deep sea sediments) and poorly constrained ages. We have recently set up a micrometeorite collection station on Kwajalein Island in the Republic of the Marshall Islands in the Pacific Ocean, using high volume air samplers to collect particles directly from the atmosphere. By collecting in this way, the terrestrial age of the particles is known, the weathering they experience is minimal, and we are able to constrain particle arrival times. Collecting at this location also exploits the considerably reduced anthropogenic background [5]. Method: High volume air samplers were installed on top of the two-story airport building on Kwajalein. These were fitted with polycarbonate membrane filters with 5µm diameter perforations. The flow rates were set to 0.5m3/min, and filters were changed once a week. After collection, filters were washed to remove salt and concentrate particles [see 5] in preparation for analysis by SEM. Results and Discussion: A selection of filters have been prepared and surveyed. Due to their ease of identification our initial investigations have focused on particles resembling cosmic spherules. The spheres can be divided into three main groups: 1. Silicate spherules rich in Al, Ca, K and Na (to varying degrees), 2. Silicate spherules rich in Mg and Fe and 3. Fe-rich spherules. Group 1 spherules are often vesiculated and can occur as aggregates. They are similar in appearance and composition to volcanic microspheres [e.g. 6] and are thus likely terrestrial in

Terrestrial invasion of pomatiopsid gastropods in the heavy-snow region of the Japanese Archipelago

Directory of Open Access Journals (Sweden)

Kato Makoto

2011-05-01

Full Text Available Abstract Background Gastropod mollusks are one of the most successful animals that have diversified in the fully terrestrial habitat. They have evolved terrestrial taxa in more than nine lineages, most of which originated during the Paleozoic or Mesozoic. The rissooidean gastropod family Pomatiopsidae is one of the few groups that have evolved fully terrestrial taxa during the late Cenozoic. The pomatiopsine diversity is particularly high in the Japanese Archipelago and the terrestrial taxa occur only in this region. In this study, we conducted thorough samplings of Japanese pomatiopsid species and performed molecular phylogenetic analyses to explore the patterns of diversification and terrestrial invasion. Results Molecular phylogenetic analyses revealed that Japanese Pomatiopsinae derived from multiple colonization of the Eurasian Continent and that subsequent habitat shifts from aquatic to terrestrial life occurred at least twice within two Japanese endemic lineages. Each lineage comprises amphibious and terrestrial species, both of which are confined to the mountains in heavy-snow regions facing the Japan Sea. The estimated divergence time suggested that diversification of these terrestrial lineages started in the Late Miocene, when active orogenesis of the Japanese landmass and establishment of snowy conditions began. Conclusions The terrestrial invasion of Japanese Pomatiopsinae occurred at least twice beside the mountain streamlets of heavy-snow regions, which is considered the first case of this event in the area. Because snow coverage maintains stable temperatures and high humidity on the ground surface, heavy-snow conditions may have paved the way for these organisms from freshwater to land via mountain streamlets by preventing winter desiccation in mountain valleys. The fact that the terrestrialization of Pomatiopsidae occurred only in year-round wet environments, but not in seasonally dried regions, provides new insight into ancient

Cosmic censorship and test particles

International Nuclear Information System (INIS)

Needham, T.

1980-01-01

In this paper one unambiguous prediction of cosmic censorship is put to the test, namely that it should be impossible to destroy a black hole (i.e. eliminate its horizon) by injecting test particles into it. Several authors have treated this problem and have not found their conclusions in contradiction with the prediction. Here we prove that if a general charged spinning particle (with parameters very much smaller than the respective hole parameters) is injected in an arbitrary manner into an extreme Kerr-Newman black hole, then cosmic censorship is upheld. As a by-product of the analysis a natural proof is given of the Christodoulou-Ruffini conditions on the injection of a spinless particle which yield a reversible black-hole transformation. Finally we consider the injection of particles with parameters that are not small compared with those of the hole, for which cosmic censorship is apparently violated. By assuming the validity of cosmic censorship we are led to a few conjectures concerning the extent of the particle's interaction with the hole while approaching it

Cosmic Strings and Their Induced Non-Gaussianities in the Cosmic Microwave Background

Directory of Open Access Journals (Sweden)

Christophe Ringeval

2010-01-01

small fraction of the CMB angular power spectrum, cosmic strings could actually be the main source of its non-Gaussianities. In this paper, after having reviewed the basic cosmological properties of a string network, we present the signatures Nambu-Goto cosmic strings would induce in various observables ranging from the one-point function of the temperature anisotropies to the bispectrum and trispectrum. It is shown that string imprints are significantly different than those expected from the primordial type of non-Gaussianity and could therefore be easily distinguished.

Arctic Terrestrial Biodiversity Monitoring Plan

DEFF Research Database (Denmark)

Christensen, Tom; Payne, J.; Doyle, M.

The Conservation of Arctic Flora and Fauna (CAFF), the biodiversity working group of the Arctic Council, established the Circumpolar Biodiversity Monitoring Program (CBMP) to address the need for coordinated and standardized monitoring of Arctic environments. The CBMP includes an international...... on developing and implementing long-term plans for monitoring the integrity of Arctic biomes: terrestrial, marine, freshwater, and coastal (under development) environments. The CBMP Terrestrial Expert Monitoring Group (CBMP-TEMG) has developed the Arctic Terrestrial Biodiversity Monitoring Plan (CBMP......-Terrestrial Plan/the Plan) as the framework for coordinated, long-term Arctic terrestrial biodiversity monitoring. The goal of the CBMP-Terrestrial Plan is to improve the collective ability of Arctic traditional knowledge (TK) holders, northern communities, and scientists to detect, understand and report on long...

Radiative transfer calculations of the diffuse ionized gas in disc galaxies with cosmic ray feedback

Science.gov (United States)

Vandenbroucke, Bert; Wood, Kenneth; Girichidis, Philipp; Hill, Alex S.; Peters, Thomas

2018-05-01

The large vertical scale heights of the diffuse ionized gas (DIG) in disc galaxies are challenging to model, as hydrodynamical models including only thermal feedback seem to be unable to support gas at these heights. In this paper, we use a three-dimensional Monte Carlo radiation transfer code to post-process disc simulations of the Simulating the Life-Cycle of Molecular Clouds project that include feedback by cosmic rays. We show that the more extended discs in simulations including cosmic ray feedback naturally lead to larger scale heights for the DIG which are more in line with observed scale heights. We also show that including a fiducial cosmic ray heating term in our model can help to increase the temperature as a function of disc scale height, but fails to reproduce observed DIG nitrogen and sulphur forbidden line intensities. We show that, to reproduce these line emissions, we require a heating mechanism that affects gas over a larger density range than is achieved by cosmic ray heating, which can be achieved by fine tuning the total luminosity of ionizing sources to get an appropriate ionizing spectrum as a function of scale height. This result sheds a new light on the relation between forbidden line emissions and temperature profiles for realistic DIG gas distributions.

Department of Cosmic Ray Physics - Overview

International Nuclear Information System (INIS)

Szabelski, J.

2006-01-01

The Department of Cosmic Ray Physics in Lodz is involved in basic research in the high energy Cosmic Ray field. Cosmic Rays are energetic particles from outside the Solar System. The energy spectrum (power law energy dependence) suggests a non-thermal origin of these particles. Most of the studies of Cosmic Rays address fundamental problems: · The nature of the physical and astrophysical processes responsible for the high energies of the particles (up to about 1020 eV/particle), · An estimation of the astrophysical conditions at the acceleration sites and/or search for sources of Cosmic Rays, · properties of high energy particle interactions at very high energies (nuclear interactions at energies exceeding energy available in the laboratories). Some Cosmic Ray studies might have practical (commercial) implications, e.g. · 'cosmic weather' forecast - predictions of geomagnetic disturbances related to Solar activity changes (due to large Solar Flares / events of Coronal Mass Ejection); these are important for large electricity networks, gas pipes, radio-wave connections, space missions and satellite experiments. Presentation of Cosmic Ray registration to high school students becomes a popular way to introduce particle physics detectors and elementary particle detection techniques to young people. Energetic Cosmic Ray particles produce cascades of particles in the atmosphere, called Extensive Air Showers (EAS). Registering EAS and their properties is the main way of experimental studies of very high energy Cosmic Rays. In the Lodz Department we run the Extensive Air Shower array where EAS are being registered. We concentrate on the studies of detection of neutrons correlated with EAS and interpretation of this phenomenon. In 2004, we started realisation of the Roland Maze Project, the network of EAS detectors placed on roofs of high schools in Lodz. We received funds from the City of Lodz budget to make a pilot project and equip 10 high schools, each with four 1 m

Tracing the cosmic web

Science.gov (United States)

Libeskind, Noam I.; van de Weygaert, Rien; Cautun, Marius; Falck, Bridget; Tempel, Elmo; Abel, Tom; Alpaslan, Mehmet; Aragón-Calvo, Miguel A.; Forero-Romero, Jaime E.; Gonzalez, Roberto; Gottlöber, Stefan; Hahn, Oliver; Hellwing, Wojciech A.; Hoffman, Yehuda; Jones, Bernard J. T.; Kitaura, Francisco; Knebe, Alexander; Manti, Serena; Neyrinck, Mark; Nuza, Sebastián E.; Padilla, Nelson; Platen, Erwin; Ramachandra, Nesar; Robotham, Aaron; Saar, Enn; Shandarin, Sergei; Steinmetz, Matthias; Stoica, Radu S.; Sousbie, Thierry; Yepes, Gustavo

2018-01-01

The cosmic web is one of the most striking features of the distribution of galaxies and dark matter on the largest scales in the Universe. It is composed of dense regions packed full of galaxies, long filamentary bridges, flattened sheets and vast low-density voids. The study of the cosmic web has focused primarily on the identification of such features, and on understanding the environmental effects on galaxy formation and halo assembly. As such, a variety of different methods have been devised to classify the cosmic web - depending on the data at hand, be it numerical simulations, large sky surveys or other. In this paper, we bring 12 of these methods together and apply them to the same data set in order to understand how they compare. In general, these cosmic-web classifiers have been designed with different cosmological goals in mind, and to study different questions. Therefore, one would not a priori expect agreement between different techniques; however, many of these methods do converge on the identification of specific features. In this paper, we study the agreements and disparities of the different methods. For example, each method finds that knots inhabit higher density regions than filaments, etc. and that voids have the lowest densities. For a given web environment, we find a substantial overlap in the density range assigned by each web classification scheme. We also compare classifications on a halo-by-halo basis; for example, we find that 9 of 12 methods classify around a third of group-mass haloes (i.e. Mhalo ∼ 1013.5 h-1 M⊙) as being in filaments. Lastly, so that any future cosmic-web classification scheme can be compared to the 12 methods used here, we have made all the data used in this paper public.

Nuclear and atomic physics governing changes in the composition of relativistic cosmic rays

International Nuclear Information System (INIS)

Wilson, L.W.

1978-05-01

Many quantitative studies of relativistic cosmic ray propagation exist in which ''standard'' values for the input quantities are adopted in an uncritical manner. In contrast, the major emphasis of this study is on developing the proper set of formulae and error estimates for each of the atomic and nuclear processes that govern the composition of the cosmic rays between lithium and nickel. In particular, it is shown that errors of approximately a factor of two exist in the standard (Bohr) cross sections for stripping, that the correction function from high energy photoionization needs to be introduced into the standard cross section for radiative attachment, and that because the half-life of a fast nucleus with at most one K-shell electron can differ from the half-life of a neutral atom, several laboratory-based values need correction. The framework used to assemble and correct these quantities is a matrix formalism for the leaky box model similar to that used by Cowsik and Wilson in their ''nested leaky box'' model. It is shown that once the assumption of species-independent leakage is introduced, the matrix formalism becomes virtually identical with the standard exponential path length formalism. 87 references

Angular correlation of cosmic neutrinos with ultrahigh-energy cosmic rays and implications for their sources

Energy Technology Data Exchange (ETDEWEB)

Moharana, Reetanjali; Razzaque, Soebur, E-mail: reetanjalim@uj.ac.za, E-mail: srazzaque@uj.ac.za [Department of Physics, University of Johannesburg, P.O. Box 524, Auckland Park 2006 (South Africa)

2015-08-01

Cosmic neutrino events detected by the IceCube Neutrino Observatory with energy 0∼> 3 TeV have poor angular resolutions to reveal their origin. Ultrahigh-energy cosmic rays (UHECRs), with better angular resolutions at 0>6 EeV energies, can be used to check if the same astrophysical sources are responsible for producing both neutrinos and UHECRs. We test this hypothesis, with statistical methods which emphasize invariant quantities, by using data from the Pierre Auger Observatory, Telescope Array and past cosmic-ray experiments. We find that the arrival directions of the cosmic neutrinos are correlated with 0≥ 10 EeV UHECR arrival directions at confidence level ≈ 90%. The strength of the correlation decreases with decreasing UHECR energy and no correlation exists at energy 0∼ 6 EeV . A search in astrophysical databases within 3{sup o} of the arrival directions of UHECRs with energy 0≥ 10 EeV, that are correlated with the IceCube cosmic neutrinos, resulted in 18 sources from the Swift-BAT X-ray catalog with redshift z≤ 0.06. We also found 3 objects in the Kühr catalog of radio sources using the same criteria. The sources are dominantly Seyfert galaxies with Cygnus A being the most prominent member. We calculate the required neutrino and UHECR fluxes to produce the observed correlated events, and estimate the corresponding neutrino luminosity (25 TeV–2.2 PeV) and cosmic-ray luminosity (500 TeV–180 EeV), assuming the sources are the ones we found in the Swift-BAT and Kühr catalogs. We compare these luminosities with the X-ray luminosity of the corresponding sources and discuss possibilities of accelerating protons to 0∼> 10 EeV and produce neutrinos in these sources.

Cosmic ray modulation

Science.gov (United States)

Agarwal Mishra, Rekha; Mishra, Rajesh Kumar

2016-07-01

Propagation of cosmic rays to and inside the heliosphere, encounter an outward moving solar wind with cyclic magnetic field fluctuation and turbulence, causing convection and diffusion in the heliosphere. Cosmic ray counts from the ground ground-based neutron monitors at different cut of rigidity show intensity changes, which are anti-correlated with sunspot numbers. They also lose energy as they propagate towards the Earth and experience various types of modulations due to different solar activity indices. In this work, we study the first three harmonics of cosmic ray intensity on geo-magnetically quiet days over the period 1965-2014 for Beijing, Moscow and Tokyo neutron monitoring stations located at different cut off rigidity. The amplitude of first harmonic remains high for low cutoff rigidity as compared to high cutoff rigidity on quiet days. The diurnal amplitude significantly decreases during solar activity minimum years. The diurnal time of maximum significantly shifts to an earlier time as compared to the corotational direction having different cutoff rigidities. The time of maximum for first harmonic significantly shifts towards later hours and for second harmonic it shifts towards earlier hours at low cutoff rigidity station as compared to the high cut off rigidity station on quiet days. The amplitude of second/third harmonics shows a good positive correlation with solar wind velocity, while the others (i.e. amplitude and phase) have no significant correlation on quiet days. The amplitude and direction of the anisotropy on quiet days does not show any significant dependence on high-speed solar wind streams for these neutron monitoring stations of different cutoff rigidity threshold. Keywords: cosmic ray, cut off rigidity, quiet days, harmonics, amplitude, phase.

Cosmic logic: a computational model

International Nuclear Information System (INIS)

Vanchurin, Vitaly

2016-01-01

We initiate a formal study of logical inferences in context of the measure problem in cosmology or what we call cosmic logic. We describe a simple computational model of cosmic logic suitable for analysis of, for example, discretized cosmological systems. The construction is based on a particular model of computation, developed by Alan Turing, with cosmic observers (CO), cosmic measures (CM) and cosmic symmetries (CS) described by Turing machines. CO machines always start with a blank tape and CM machines take CO's Turing number (also known as description number or Gödel number) as input and output the corresponding probability. Similarly, CS machines take CO's Turing number as input, but output either one if the CO machines are in the same equivalence class or zero otherwise. We argue that CS machines are more fundamental than CM machines and, thus, should be used as building blocks in constructing CM machines. We prove the non-computability of a CS machine which discriminates between two classes of CO machines: mortal that halts in finite time and immortal that runs forever. In context of eternal inflation this result implies that it is impossible to construct CM machines to compute probabilities on the set of all CO machines using cut-off prescriptions. The cut-off measures can still be used if the set is reduced to include only machines which halt after a finite and predetermined number of steps

The intergalactic propagation of ultrahigh energy cosmic ray nuclei

Energy Technology Data Exchange (ETDEWEB)

Hooper, Dan; /Fermilab; Sarkar, Subir; /Oxford U., Theor. Phys.; Taylor, Andrew M.; /Oxford U.

2006-08-01

We investigate the propagation of ultra-high energy cosmic ray nuclei (A = 1-56) from cosmologically distant sources through the cosmic radiation backgrounds. Various models for the injected composition and spectrum and of the cosmic infrared background are studied using updated photodisintegration cross-sections. The observational data on the spectrum and the composition of ultra-high energy cosmic rays are jointly consistent with a model where all of the injected primary cosmic rays are iron nuclei (or a mixture of heavy and light nuclei).

Microplastics in the terrestrial ecosystem: Implications for Lumbricus terrestris (Oligochaeta, Lumbricidae)

NARCIS (Netherlands)

Huerta Lwanga, Esperanza; Gertsen, H.F.; Gooren, H.; Peters, P.D.; Salanki, T.E.; Ploeg, van der M.J.C.; Besseling, E.; Koelmans, A.A.; Geissen, V.

2016-01-01

Plastic debris is widespread in the environment, but information on the effects of microplastics on terrestrial fauna is completely lacking. Here, we studied the survival and fitness of the earthworm Lumbricus terrestris (Oligochaeta, Lumbricidae) exposed to microplastics (Polyethylene, <150 μm)

Lincos: An interplanetary language. [mathematical method for cosmic radio contact with extraterrestrial life

Science.gov (United States)

Freudenthal, H.

1974-01-01

A language for cosmic contacts is envisioned that utilizes radio signals of different wavelengths as sounds to form words. These words are in most cases abbreviations of Latin words understood from their English and French cognates. The logistic syntax uses pauses for punctuation in a binary system; pairs of algebraic formulas are transmitted where in a such pair the second element is always derived from the first; between them is transmitted a word that is understood as -follows- by the listener. The concepts of difference in position, of motion, of space, and of mass can be mathematically described by this language.

Qigong meets quantum physics experiencing cosmic oneness

CERN Document Server

Bock-Möbius, Imke

2012-01-01

Quantum physicists have reached a point commonly only attained by mystics: they understand something with amazing clarity yet can only talk about it in parables and metaphors. In this context, qigong with its Daoist background is a powerful way to integrate these apparently opposing ways of apperception and understanding. It allows us to realise cosmic oneness in the activities of daily life. This book succeeds in presenting both an easily accessible outline of quantum physics and also an appreciation of mysticism beyond vagueness and obscurity. From here it describes the physical and mental movements of qigong as a way of integrating body and mind, head and heart, detailing specific exercises and outlining their rationale and effects.

Progress in high-energy cosmic ray physics

Science.gov (United States)

Mollerach, S.; Roulet, E.

2018-01-01

We review some of the recent progress in our knowledge about high-energy cosmic rays, with an emphasis on the interpretation of the different observational results. We discuss the effects that are relevant to shape the cosmic ray spectrum and the explanations proposed to account for its features and for the observed changes in composition. The physics of air-showers is summarized and we also present the results obtained on the proton-air cross section and on the muon content of the showers. We discuss the cosmic ray propagation through magnetic fields, the effects of diffusion and of magnetic lensing, the cosmic ray interactions with background radiation fields and the production of secondary neutrinos and photons. We also consider the cosmic ray anisotropies, both at large and small angular scales, presenting the results obtained from the TeV up to the highest energies and discuss the models proposed to explain their origin.

To the problem of superfluous cosmic radiation

International Nuclear Information System (INIS)

Savenko, I.A.; Saraeva, M.A.; Shavrin, P.I.

1979-01-01

From consideration of a number of basic works on the excessive cosmic radiation given is the most probable composition (electron, proton, and nuclear components) of this radiation in equatorial regions at altitudes corresponding to minimum altitudes of the drift trajectories hsub(min) <= 0, in case of detecting by detector on the artificial satellite of the Earth (ASE) with the mass up to 1t and of the heavier ASE. The disagreement in spectra of solar cosmic rays obtained along the latitude effect on the ASE. ''Molniya-1'' and in the experiments out of the magnetosphere on the ASE ''Explorer-41'' is explained by excessive radiation production of solar cosmic rays. The comparison of readings of the neutron channel with those of the charged particle channels of the apparatus on the ASE ''Molniya-1'' during the proton event on 25.01.1971 does not contradict to the supposition on the similarity of excessive cosmic radiation production of galactic and solar cosmic rays

LHCf sheds new light on cosmic rays

CERN Multimedia

Anaïs Schaeffer

2011-01-01

The energy spectrum of the single photon obtained using data from the LHCf experiment has turned out to be very different from that predicted by the theoretical models used until now to describe the interactions between very high-energy cosmic rays and the earth's atmosphere. The consequences of this discrepancy for cosmic ray studies could be significant.   Artistic impression of cosmic rays entering Earth's atmosphere. (Credit: Asimmetrie/Infn). It took physicists by surprise when analysis of the data collected by the two LHCf calorimeters in 2010 showed that high-energy cosmic rays don't interact with the atmosphere in the manner predicted by theory. The LHCf detectors, set up 140 metres either side of the ATLAS interaction point, are dedicated to the study of the secondary particles emitted at very small angles during proton-proton collisions in the LHC, with energies comparable to cosmic rays entering the earth's atmosphere at 2.5x1016 eV. The aim of the experiment is to r...

Cosmic rays and tests of fundamental principles

Science.gov (United States)

Gonzalez-Mestres, Luis

2011-03-01

It is now widely acknowledged that cosmic rays experiments can test possible new physics directly generated at the Planck scale or at some other fundamental scale. By studying particle properties at energies far beyond the reach of any man-made accelerator, they can yield unique checks of basic principles. A well-known example is provided by possible tests of special relativity at the highest cosmic-ray energies. But other essential ingredients of standard theories can in principle be tested: quantum mechanics, uncertainty principle, energy and momentum conservation, effective space-time dimensions, hamiltonian and lagrangian formalisms, postulates of cosmology, vacuum dynamics and particle propagation, quark and gluon confinement, elementariness of particles…Standard particle physics or string-like patterns may have a composite origin able to manifest itself through specific cosmic-ray signatures. Ultra-high energy cosmic rays, but also cosmic rays at lower energies, are probes of both "conventional" and new Physics. Status, prospects, new ideas, and open questions in the field are discussed.

Cosmic rays and tests of fundamental principles

International Nuclear Information System (INIS)

Gonzalez-Mestres, Luis

2011-01-01

It is now widely acknowledged that cosmic rays experiments can test possible new physics directly generated at the Planck scale or at some other fundamental scale. By studying particle properties at energies far beyond the reach of any man-made accelerator, they can yield unique checks of basic principles. A well-known example is provided by possible tests of special relativity at the highest cosmic-ray energies. But other essential ingredients of standard theories can in principle be tested: quantum mechanics, uncertainty principle, energy and momentum conservation, effective space-time dimensions, hamiltonian and lagrangian formalisms, postulates of cosmology, vacuum dynamics and particle propagation, quark and gluon confinement, elementariness of particles... Standard particle physics or string-like patterns may have a composite origin able to manifest itself through specific cosmic-ray signatures. Ultra-high energy cosmic rays, but also cosmic rays at lower energies, are probes of both 'conventional' and new Physics. Status, prospects, new ideas, and open questions in the field are discussed.

Technologies for low radio frequency observations of the Cosmic Dawn

Science.gov (United States)

Jones, D. L.

2014-03-01

The Jet Propulsion Laboratory (JPL) is developing concepts and technologies for low frequency radio astronomy space missions aimed at observing highly redshifted neutral Hydrogen from the Dark Ages. This is the period of cosmic history between the recombination epoch when the microwave background radiation was produced and the re-ionization of the intergalactic medium by the first generation of stars (Cosmic Dawn). This period, at redshifts z > ~20, is a critical epoch for the formation and evolution of large-scale structure in the universe. The 21-cm spectral line of Hydrogen provides the most promising method for directly studying the Dark Ages, but the corresponding frequencies at such large redshifts are only tens of MHz and thus require space-based observations to avoid terrestrial RFI and ionospheric absorption and refraction. This paper reports on the status of several low frequency technology development activities at JPL, including deployable bi-conical dipoles for a planned lunar-orbiting mission, and both rover-deployed and inflation-deployed long dipole antennas for use on the lunar surface. In addition, recent results from laboratory testing of low frequency receiver designs are presented. Finally, several concepts for space-based imaging interferometers utilizing deployable low frequency antennas are described. Some of these concepts involve large numbers of antennas and consequently a large digital cross-correlator will be needed. JPL has studied correlator architectures that greatly reduce the DC power required for this step, which can dominate the power consumption of real-time signal processing. Strengths and weaknesses of each mission concept are discussed in the context of the additional technology development required.

Low-energy cosmic rays in the Orion region

DEFF Research Database (Denmark)

Pohl, M.

1998-01-01

The recently observed nuclear gamma-ray line emission from the Orion complex implies a high flux of low-energy cosmic rays (LECR) with unusual abundance. This cosmic ray component would dominate the energy density, pressure, and ionising power of cosmic rays, and thus would have a strong impact...

Does a cosmic censor exist

International Nuclear Information System (INIS)

Israel, W.

1984-01-01

A distinction is drawn between the event horizon conjecture (EHC), the conjecture that an event horizon forms in a gravitational collapse, and cosmic censorship, the idea that every singularity which develops in the course of collapse must be enclosed within a horizon. It is argued that a body of circumstantial evidence seems to favor EHC, but cosmic censorship seems contraindicated

Diffuse fluxes of cosmic high-energy neutrinos

International Nuclear Information System (INIS)

Stecker, F.W.

1979-01-01

Production spectra of high-energy neutrinos from galactic cosmic-ray interactions with interstellar gas and extragalactic ultrahigh-energy cosmic-ray interactions with microwave blackbody photons are presented and discussed. These production processes involve the decay of charged pions and are thus related to the production of cosmic γ-rays from the decay of neutral pions. Estimates of the neutrino fluxes from various diffuse cosmic sources are then made, and the reasons for significant differences with previous estimates are discussed. Small predicted event rates for a DUMAND type detection system, combined with a possible significant flux of prompt neutrinos from the atmosphere above 50 TeV, may make the study of diffuse extraterrestrial neutrinos more difficult than previously thought

Cosmic Rays and Climate

CERN Document Server

Kirkby, Jasper

2007-01-01

Among the most puzzling questions in climate change is that of solar-climate variability, which has attracted the attention of scientists for more than two centuries. Until recently, even the existence of solar-climate variability has been controversial—perhaps because the observations had largely involved correlations between climate and the sunspot cycle that had persisted for only a few decades. Over the last few years, however, diverse reconstructions of past climate change have revealed clear associations with cosmic ray variations recorded in cosmogenic isotope archives, providing persuasive evidence for solar or cosmic ray forcing of the climate. However, despite the increasing evidence of its importance, solar-climate variability is likely to remain controversial until a physical mechanism is established. Although this remains a mystery, observations suggest that cloud cover may be influenced by cosmic rays, which are modulated by the solar wind and, on longer time scales, by the geomagnetic fiel...

Atmospheric and biospheric effects of cosmic

International Nuclear Information System (INIS)

Cardenas, Rolando

2007-01-01

We briefly review and classify the action that different sources of cosmic radiations might have had on Earth climate and biosphere in the geological past and at present times. We present the action of both sparse explosive phenomena, like gamma-ray bursts and supernovae, and permanent ones like cosmic rays and ultraviolet radiation backgrounds. Very energetic cosmic radiation coming from explosions can deplete the ozone lawyer due to initial ionization reactions, while soft backgrounds might trigger low altitude cloud formation through certain microphysical amplification processes. We examine a hypothesis concerning the potential role of cosmic rays on present Global Climatic Change. We also present the potential of UV astronomy to probe some of above scenarios, and speak on the possibilities for the Cuban participation in the international mega-project World Space Observatory, a UV telescope to be launched in the period 2007-2009. (Author)

The origin of life: The growing evidence for panspermia

International Nuclear Information System (INIS)

Wickramasinghe, C.

2008-01-01

Evidence from astronomy, biology, and geology are converging to point to life being a cosmic phenomenon. Microbial life was already evolved and widely dispersed in the galaxy at the time of the formation of the solar nebula. Life on Earth originates with the warm liquid interiors of comets amplifying an incipient galactic microbiology, and introducing viable microbes onto the planet

Cosmology with cosmic shear observations: a review.

Science.gov (United States)

Kilbinger, Martin

2015-07-01

Cosmic shear is the distortion of images of distant galaxies due to weak gravitational lensing by the large-scale structure in the Universe. Such images are coherently deformed by the tidal field of matter inhomogeneities along the line of sight. By measuring galaxy shape correlations, we can study the properties and evolution of structure on large scales as well as the geometry of the Universe. Thus, cosmic shear has become a powerful probe into the nature of dark matter and the origin of the current accelerated expansion of the Universe. Over the last years, cosmic shear has evolved into a reliable and robust cosmological probe, providing measurements of the expansion history of the Universe and the growth of its structure. We review here the principles of weak gravitational lensing and show how cosmic shear is interpreted in a cosmological context. Then we give an overview of weak-lensing measurements, and present the main observational cosmic-shear results since it was discovered 15 years ago, as well as the implications for cosmology. We then conclude with an outlook on the various future surveys and missions, for which cosmic shear is one of the main science drivers, and discuss promising new weak cosmological lensing techniques for future observations.

Microplastics in the Terrestrial Ecosystem: Implications for Lumbricus terrestris (Oligochaeta, Lumbricidae).

Science.gov (United States)

Huerta Lwanga, Esperanza; Gertsen, Hennie; Gooren, Harm; Peters, Piet; Salánki, Tamás; van der Ploeg, Martine; Besseling, Ellen; Koelmans, Albert A; Geissen, Violette

2016-03-01

Plastic debris is widespread in the environment, but information on the effects of microplastics on terrestrial fauna is completely lacking. Here, we studied the survival and fitness of the earthworm Lumbricus terrestris (Oligochaeta, Lumbricidae) exposed to microplastics (Polyethylene, digestion of ingested organic matter, microplastic was concentrated in cast, especially at the lowest dose (i.e., 7% in litter) because that dose had the highest proportion of digestible organic matter. Whereas 50 percent of the microplastics had a size of earthworms. These concentration-transport and size-selection mechanisms may have important implications for fate and risk of microplastic in terrestrial ecosystems.

Cosmic ray riddle solved?

International Nuclear Information System (INIS)

Anon.

1995-01-01

Full text: Physicists from Japan and the United States have discovered a possible answer to the puzzle of the origin of high energy cosmic rays that bombard Earth from all directions in space. Using data from the Japanese/US X-ray astronomical satellite ASCA, physicists have found strong evidence for the production of cosmic particles in the shock wave of a supernova remnant, the expanding fireball produced by the explosion of a star. Primary cosmic rays, mostly electrons and protons, travel near the speed of light. Each second, approximately 4 such particles cross one square centimetre of space just outside the Earth's atmosphere. Subsequently, collisions of these primary particles with atoms in the upper atmosphere produce slower secondary particles. Ever since the discovery of cosmic rays early this century, scientists have debated the origin of these particles and how they can be accelerated to such high speeds. Supernova remnants have long been thought to provide the high energy component, but the evidence has been lacking until now. The international team of investigators used the satellite to determine that cosmic rays are generated profusely in the remains of the supernova of 1006 AD - which appeared to medieval viewers to be as bright as the Moon - and that they are accelerated to high velocities by an iterative process first suggested by Enrico Fermi in 1949. Using solid-state X-ray cameras, the ASCA satellite records simultaneous images and spectra of X-rays from celestial sources, allowing astronomers to distinguish different types of X-ray emission. The tell-tale clue to the discovery was the detection of two diametrically opposite regions in the rapidly expanding supernova remnant, the debris from the stellar explosion. The two regions glow intensely from the synchrotron radiation produced when fast-moving electrons are bent by a magnetic field. The remainder of the supernova remnant, in contrast, emits ordinary ''thermal'' X

Cosmic Ray Interactions in Shielding Materials

International Nuclear Information System (INIS)

Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Ankney, Austin S.; Orrell, John L.; Berguson, Timothy J.; Troy, Meredith D.

2011-01-01

This document provides a detailed study of materials used to shield against the hadronic particles from cosmic ray showers at Earth's surface. This work was motivated by the need for a shield that minimizes activation of the enriched germanium during transport for the MAJORANA collaboration. The materials suitable for cosmic-ray shield design are materials such as lead and iron that will stop the primary protons, and materials like polyethylene, borated polyethylene, concrete and water that will stop the induced neutrons. The interaction of the different cosmic-ray components at ground level (protons, neutrons, muons) with their wide energy range (from kilo-electron volts to giga-electron volts) is a complex calculation. Monte Carlo calculations have proven to be a suitable tool for the simulation of nucleon transport, including hadron interactions and radioactive isotope production. The industry standard Monte Carlo simulation tool, Geant4, was used for this study. The result of this study is the assertion that activation at Earth's surface is a result of the neutronic and protonic components of the cosmic-ray shower. The best material to shield against these cosmic-ray components is iron, which has the best combination of primary shielding and minimal secondary neutron production.

Cosmic gamma-ray background radiation. Current understandings and problems

International Nuclear Information System (INIS)

Inoue, Yoshiyuki

2015-01-01

The cosmic gamma-ray background radiation is one of the most fundamental observables in the gamma-ray band. Although the origin of the cosmic gamma-ray background radiation has been a mystery for a long time, the Fermi gamma-ray space telescope has recently measured it at 0.1-820 GeV and revealed that the cosmic GeV gamma-ray background is composed of blazars, radio galaxies, and star-forming galaxies. However, Fermi still leaves the following questions. Those are dark matter contribution, origins of the cosmic MeV gamma-ray background, and the connection to the IceCube TeV-PeV neutrino events. In this proceeding, I will review the current understandings of the cosmic gamma-ray background and discuss future prospects of cosmic gamma-ray background radiation studies. (author)

Phenomenology of cosmic phase transitions

International Nuclear Information System (INIS)

Kaempfer, B.; Lukacs, B.; Paal, G.

1989-11-01

The evolution of the cosmic matter from Planck temperature to the atomic combination temperature is considered from a phenomenological point of view. Particular emphasis is devoted to the sequence of cosmic phase transitions. The inflationary era at the temperature of the order of the grand unification energy scale and the quantum chromodynamic confinement transition are dealt with in detail. (author) 131 refs.; 26 figs

Cosmic microwave background, where next?

CERN Multimedia

CERN. Geneva

2009-01-01

Ground-based, balloon-borne and space-based experiments will observe the Cosmic Microwave Background in greater details to address open questions about the origin and the evolution of the Universe. In particular, detailed observations the polarization pattern of the Cosmic Microwave Background radiation have the potential to directly probe physics at the GUT scale and illuminate aspects of the physics of the very early Universe.

Cosmic rays and Earth's climate

DEFF Research Database (Denmark)

Svensmark, Henrik

2000-01-01

During the last solar cycle the Earth's cloud cover underwent a modulation in phase with the cosmic ray flux. Assuming that there is a causal relationship between the two, it is expected and found that the Earth's temperature follows more closely decade variations in cosmic ray flux than other...... solar activity parameters. If the relationship is real the state of the Heliosphere affects the Earth's climate....

The Spine of the Cosmic Web

NARCIS (Netherlands)

Aragón-Calvo, Miguel A.; Platen, Erwin; van de Weijgaert, Rien; Szalay, Alexander S.

2010-01-01

We present the SpineWeb framework for the topological analysis of the Cosmic Web and the identification of its walls, filaments, and cluster nodes. Based on the watershed segmentation of the cosmic density field, the SpineWeb method invokes the local adjacency properties of the boundaries between

The Spine of the Cosmic Web

NARCIS (Netherlands)

Aragón-Calvo, Miguel A.; Platen, Erwin; van de Weijgaert, Rien; Szalay, Alexander S.

We present the SpineWeb framework for the topological analysis of the Cosmic Web and the identification of its walls, filaments, and cluster nodes. Based on the watershed segmentation of the cosmic density field, the SpineWeb method invokes the local adjacency properties of the boundaries between

NEXUS: tracing the cosmic web connection

NARCIS (Netherlands)

Cautun, Marius; van de Weygaert, Rien; Jones, Bernard J. T.

2013-01-01

We introduce the NEXUS algorithm for the identification of cosmic web environments: clusters, filaments, walls and voids. This is a multiscale and automatic morphological analysis tool that identifies all the cosmic structures in a scale free way, without preference for a certain size or shape. We

Smooth halos in the cosmic web

Energy Technology Data Exchange (ETDEWEB)

Gaite, José, E-mail: jose.gaite@upm.es [Physics Dept., ETSIAE, IDR, Universidad Politécnica de Madrid, Pza. Cardenal Cisneros 3, E-28040 Madrid (Spain)

2015-04-01

Dark matter halos can be defined as smooth distributions of dark matter placed in a non-smooth cosmic web structure. This definition of halos demands a precise definition of smoothness and a characterization of the manner in which the transition from smooth halos to the cosmic web takes place. We introduce entropic measures of smoothness, related to measures of inequality previously used in economy and with the advantage of being connected with standard methods of multifractal analysis already used for characterizing the cosmic web structure in cold dark matter N-body simulations. These entropic measures provide us with a quantitative description of the transition from the small scales portrayed as a distribution of halos to the larger scales portrayed as a cosmic web and, therefore, allow us to assign definite sizes to halos. However, these ''smoothness sizes'' have no direct relation to the virial radii. Finally, we discuss the influence of N-body discreteness parameters on smoothness.

Lightning Discharges, Cosmic Rays and Climate

Science.gov (United States)

Kumar, Sanjay; Siingh, Devendraa; Singh, R. P.; Singh, A. K.; Kamra, A. K.

2018-03-01

The entirety of the Earth's climate system is continuously bombarded by cosmic rays and exhibits about 2000 thunderstorms active at any time of the day all over the globe. Any linkage among these vast systems should have global consequences. Numerous studies done in the past deal with partial links between some selected aspects of this grand linkage. Results of these studies vary from weakly to strongly significant and are not yet complete enough to justify the physical mechanism proposed to explain such links. This review is aimed at presenting the current understanding, based on the past studies on the link between cosmic ray, lightning and climate. The deficiencies in some proposed links are pointed out. Impacts of cosmic rays on engineering systems and the possible effects of cosmic rays on human health are also briefly discussed. Also enumerated are some problems for future work which may help in developing the grand linkage among these three vast systems.

Cosmic ray propagation with CRPropa 3

International Nuclear Information System (INIS)

Batista, R Alves; Evoli, C; Sigl, G; Van Vliet, A; Erdmann, M; Kuempel, D; Mueller, G; Walz, D; Kampert, K-H; Winchen, T

2015-01-01

Solving the question of the origin of ultra-high energy cosmic rays (UHECRs) requires the development of detailed simulation tools in order to interpret the experimental data and draw conclusions on the UHECR universe. CRPropa is a public Monte Carlo code for the galactic and extragalactic propagation of cosmic ray nuclei above ∼ 10 17 eV, as well as their photon and neutrino secondaries. In this contribution the new algorithms and features of CRPropa 3, the next major release, are presented. CRPropa 3 introduces time-dependent scenarios to include cosmic evolution in the presence of cosmic ray deflections in magnetic fields. The usage of high resolution magnetic fields is facilitated by shared memory parallelism, modulated fields and fields with heterogeneous resolution. Galactic propagation is enabled through the implementation of galactic magnetic field models, as well as an efficient forward propagation technique through transformation matrices. To make use of the large Python ecosystem in astrophysics CRPropa 3 can be steered and extended in Python. (paper)

Smooth halos in the cosmic web

International Nuclear Information System (INIS)

Gaite, José

2015-01-01

Dark matter halos can be defined as smooth distributions of dark matter placed in a non-smooth cosmic web structure. This definition of halos demands a precise definition of smoothness and a characterization of the manner in which the transition from smooth halos to the cosmic web takes place. We introduce entropic measures of smoothness, related to measures of inequality previously used in economy and with the advantage of being connected with standard methods of multifractal analysis already used for characterizing the cosmic web structure in cold dark matter N-body simulations. These entropic measures provide us with a quantitative description of the transition from the small scales portrayed as a distribution of halos to the larger scales portrayed as a cosmic web and, therefore, allow us to assign definite sizes to halos. However, these ''smoothness sizes'' have no direct relation to the virial radii. Finally, we discuss the influence of N-body discreteness parameters on smoothness

Large vessel imaging using cosmic-ray muons

International Nuclear Information System (INIS)

Jenneson, P.M.

2004-01-01

Cosmic-ray muons are assessed for their practical use in the tomographic imaging of the internal composition of large vessels over 2 m in diameter. The technique is based on the attenuation and scattering of cosmic-ray muons passing through a vessel and has advantages over photon-based methods of tomography that it is extendable to object containing high-density materials over many tens of metres. The main disadvantage is the length of time required to produce images of sufficient resolution and hence cosmic ray muon tomography will be most suited to the imaging of large structures whose internal composition is effectively static for the duration of the imaging period. Simulation and theoretical results are presented here which demonstrate the feasibility of cosmic ray muon tomography

Cosmic ray antimatter and baryon symmetric cosmology

Science.gov (United States)

Stecker, F. W.; Protheroe, R. J.; Kazanas, D.

1982-01-01

The relative merits and difficulties of the primary and secondary origin hypotheses for the observed cosmic-ray antiprotons, including the new low-energy measurement of Buffington, et al. We conclude that the cosmic-ray antiproton data may be evidence for antimatter galaxies and baryon symmetric cosmology. The present bar P data are consistent with a primary extragalactic component having /p=/equiv 1+/- 3.2/0.7x10 = to the -4 independent of energy. We propose that the primary extragalactic cosmic ray antiprotons are most likely from active galaxies and that expected disintegration of bar alpha/alpha ban alpha/alpha. We further predict a value for ban alpha/alpha =/equiv 10 to the -5, within range of future cosmic ray detectors.

Solar flares and the cosmic ray intensity

International Nuclear Information System (INIS)

Hatton, C.J.

1980-01-01

The relationship between the cosmic ray intensity and solar activity during solar cycle 20 is discussed. A model is developed whereby it is possible to simulate the observed cosmic ray intensity from the observed number of solar flares of importance >= 1. This model leads to a radius for the modulation region of 60-70 AU. It is suggested that high speed solar streams also made a small contribution to the modulation of cosmic rays during solar cycle 20. (orig.)

Cosmic-ray-modified stellar winds. III. A numerical iterative approach

International Nuclear Information System (INIS)

Ko, C.M.; Jokipii, J.R.; Webb, G.M.

1988-01-01

A numerical iterative method is used to determine the modification of a stellar wind flow with a termination shock by the galactic cosmic rays. A two-fluid model consisting of cosmic rays and thermal stellar wind gas is used in which the cosmic rays are coupled to the background flow via scattering with magnetohydrodynamic waves or irregularities. A polytropic model is used to describe the thermal stellar wind gas, and the cosmic-rays are modeled as a hot, low-density gas with negligible mass flux. The positive galactic cosmic-ray pressure gradient serves to brake the outflowing stellar wind gas, and the cosmic rays modify the location of the critical point of the wind, the location of the shock, the wind fluid velocity profile, and the thermal gas entropy constants on both sides of the shock. The transfer of energy to the cosmic rays results in an outward radial flux of cosmic-ray energy. 21 references

Prospects for Detecting Thermal Emission from Terrestrial Exoplanets with JWST

Science.gov (United States)

Kreidberg, Laura

2018-01-01

A plethora of nearby, terrestrial exoplanets has been discovered recently by ground-based surveys. Excitingly, some of these are in the habitable zones of their host stars, and may be hospitable for life. However, all the planets orbit small, cool stars and have considerably different irradiation environments from the Earth, making them vulnerable to atmospheric escape, erosion and collapse. Atmosphere characterization is therefore critical to assessing the planets' habitability. I will discuss possible JWST thermal emission measurements to determine the atmospheric properties of nearby terrestrial planets. I will focus on prospects for detecting physically motivated atmospheres for planets orbiting LHS 1140, GJ 1132, and TRAPPIST-1. I will also discuss the potential for using phase curve observations to determine whether an atmosphere has survived on the non-transiting planet Proxima b.

V. Terrestrial vertebrates

Science.gov (United States)

Dean Pearson; Deborah Finch

2011-01-01

Within the Interior West, terrestrial vertebrates do not represent a large number of invasive species relative to invasive weeds, aquatic vertebrates, and invertebrates. However, several invasive terrestrial vertebrate species do cause substantial economic and ecological damage in the U.S. and in this region (Pimental 2000, 2007; Bergman and others 2002; Finch and...

A disintegrating cosmic string

International Nuclear Information System (INIS)

Griffiths, J B; Docherty, P

2002-01-01

We present a simple sandwich gravitational wave of the Robinson-Trautman family. This is interpreted as representing a shock wave with a spherical wavefront which propagates into a Minkowski background minus a wedge (i.e. the background contains a cosmic string). The deficit angle (the tension) of the string decreases through the gravitational wave, which then ceases. This leaves an expanding spherical region of Minkowski space behind it. The decay of the cosmic string over a finite interval of retarded time may be considered to generate the gravitational wave. (letter to the editor)

Feasibility study on a cosmic-ray level gauge

International Nuclear Information System (INIS)

Matsuda, H.; Fukaya, M.; Minato, S.

1989-01-01

Cosmic-ray intensities were measured at the stairs in a subway station in Nagoya City, inside a tall concrete building and under a cylindrical water tank, to examine the feasibility of a cosmic-ray level gauge. The measured results agreed quite well with the theoretical calculations. These results show that a cosmic-ray level gauge is feasible. (author)

Terrestrial ecological responses of climate change in the Northern hemisphere

International Nuclear Information System (INIS)

Forchhammer, M.C.

2001-01-01

Focusing on the single most important atmospheric phenomenon in the Northern hemisphere, the North Atlantic Oscillation (NAO), the author reviews the recent studies coupling the NAO with the ecology of a wide range of terrestrial organisms. In particular, the author focuses on low variations in the NAO affect phenotypic variation in life history Traits and, ultimately, dynamics of populations and of interacting species. (LN)

Ecological succession reveals potential signatures of marine-terrestrial transition in salt marsh fungal communities

NARCIS (Netherlands)

Dini-Andreote, Francisco; Pylro, Victor Satler; Baldrian, Petr; van Elsas, Jan Dirk; Salles, Joana Falcão

Marine-to-terrestrial transition represents one of the most fundamental shifts in microbial life. Understanding the distribution and drivers of soil microbial communities across coastal ecosystems is critical given the roles of microbes in soil biogeochemistry and their multifaceted influence on

Second Symposium on Chemical Evolution and the Origin of Life

International Nuclear Information System (INIS)

Devincenzi, D.L.; Dufour, P.A.

1986-05-01

Recent findings by NASA Exobiology investigators are reported. Scientific papers are presented in the following areas: cosmic evolution of biogenic compounds, prebiotic evolution (planetary and molecular), early evolution of life (biological and geochemical), evolution of advanced life, solar system exploration, and the Search for Extraterrestrial Intelligence (SETI)

Homochirality as the signature of life: the SETH Cigar

Science.gov (United States)

MacDermott, A. J.; Barron, L. D.; Brack, A.; Buhse, T.; Drake, A. F.; Emery, R.; Gottarelli, G.; Greenberg, J. M.; Haberle, R.; Hegstrom, R. A.; Hobbs, K.; Kondepudi, D. K.; McKay, C.; Moorbath, S.; Raulin, F.; Sandford, M.; Schwartzman, D. W.; Thiemann, W. H.-P.; Tranter, G. E.; Zarnecki, J. C.

1996-11-01

A characteristic hallmark of life is its homochirality; all biomolecules are usually of one hand, e.g. on Earth life uses only L-amino acids for protein synthesis and not their D mirror images. It is therefore suggested that a search for extra-terrestrial life can be approached as a Search for Extra-Terrestrial Homochirality (SETH). A novel miniaturized space polarimeter, called the SETH Cigar, is described which could be used to detect optical rotation as the homochiral signature of life on other planets. Moving parts are avoided by replacing the normal rotating polarizer by multiple fixed polarizers at different angles as in the eye of the bee. It is believed that homochirality will be found in the subsurface layers on Mars as a relic of extinct life.

One century of cosmic rays – A particle physicist's view

Directory of Open Access Journals (Sweden)

Sutton Christine

2015-01-01

Full Text Available Experiments on cosmic rays and the elementary particles share a common history that dates back to the 19th century. Following the discovery of radioactivity in the 1890s, the paths of the two fields intertwined, especially during the decades after the discovery of cosmic rays. Experiments demonstrated that the primary cosmic rays are positively charged particles, while other studies of cosmic rays revealed various new sub-atomic particles, including the first antiparticle. Techniques developed in common led to the birth of neutrino astronomy in 1987 and the first observation of a cosmic γ-ray source by a ground-based cosmic-ray telescope in 1989.

Propagation of ultrahigh-energy cosmic rays

Energy Technology Data Exchange (ETDEWEB)

Stanev, Todor [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)], E-mail: stanev@bartol.udel.edu

2009-06-15

We briefly describe the energy loss processes of ultrahigh-energy protons, heavier nuclei and {gamma}-rays in interactions with the universal photon fields of the Universe. We then discuss the modification of the accelerated cosmic-ray energy spectrum in propagation by the energy loss processes and the charged cosmic-ray scattering in the extragalactic magnetic fields. The energy lost by the ultrahigh-energy cosmic rays goes into {gamma}-rays and neutrinos that carry additional information about the sources of highest energy particles. The new experimental results of the HiRes and the Auger collaborations are discussed in view of the predictions from propagation calculations.

Fluctuations in the cosmic microwave background

International Nuclear Information System (INIS)

Banday, A.J.; Wolfendale, A.W.

1990-01-01

In view of the importance to contemporary cosmology, and to our understanding of the Universe, of the precise nature of the Cosmic Microwave Background (CMB) spectrum, we consider the effects on this spectrum of contamination by other radiation fields of both galactic and extragalactic origin. Particular attention is given to the significance of measurements of the fluctuations in the 'background' radiation detected at 10.46 GHz and we conclude that these fluctuations are of the same magnitude as those expected from galactic cosmic-ray effects. A more detailed study of the cosmic-ray induced fluctuations and measurements at higher frequencies will be needed before genuine CMB fluctuations can be claimed. (author)

Cosmic growth history and expansion history

International Nuclear Information System (INIS)

Linder, Eric V.

2005-01-01

The cosmic expansion history tests the dynamics of the global evolution of the universe and its energy density contents, while the cosmic growth history tests the evolution of the inhomogeneous part of the energy density. Precision comparison of the two histories can distinguish the nature of the physics responsible for the accelerating cosmic expansion: an additional smooth component--dark energy--or a modification of the gravitational field equations. With the aid of a new fitting formula for linear perturbation growth accurate to 0.05%-0.2%, we separate out the growth dependence on the expansion history and introduce a new growth index parameter γ that quantifies the gravitational modification

Robustness of cosmic neutrino background detection in the cosmic microwave background

Energy Technology Data Exchange (ETDEWEB)

Audren, Benjamin [Institut de Théorie des Phénomènes Physiques, École Polytechnique Fédérale de Lausanne, CH-1015, Lausanne (Switzerland); Bellini, Emilio; Cuesta, Antonio J.; Verde, Licia [Institut de Ciències del Cosmos, Universitat de Barcelona, IEEC-UB, Martí i Franquès 1, E08028 Barcelona (Spain); Gontcho, Satya Gontcho A; Pérez-Ràfols, Ignasi [Dept. d' Astronomia i Meteorologia, Institut de Ciències del Cosmos, Universitat de Barcelona, IEEC-UB, Martí i Franquès 1, E08028 Barcelona (Spain); Lesgourgues, Julien [CERN, Theory Division, CH-1211 Geneva 23 (Switzerland); Niro, Viviana [Departamento de Física Teórica, Universidad Autónoma de Madrid and Instituto de Física Teórica UAM/CSIC, Calle Nicolás Cabrera 13-15, Cantoblanco, E-28049 Madrid (Spain); Pellejero-Ibanez, Marcos; Tramonte, Denis [Instituto de Astrofísica de Canarias (IAC), C/Vía Láctea s/n, E-38200, La Laguna, Tenerife (Spain); Poulin, Vivian [LAPTh, Université de Savoie, CNRS, B.P.110, Annecy-le-Vieux F-74941 (France); Tram, Thomas, E-mail: emilio.bellini@icc.ub.edu [Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Burnaby Road, Portsmouth PO1 3FX (United Kingdom)

2015-03-01

The existence of a cosmic neutrino background can be probed indirectly by CMB experiments, not only by measuring the background density of radiation in the universe, but also by searching for the typical signatures of the fluctuations of free-streaming species in the temperature and polarisation power spectrum. Previous studies have already proposed a rather generic parametrisation of these fluctuations, that could help to discriminate between the signature of ordinary free-streaming neutrinos, or of more exotic dark radiation models. Current data are compatible with standard values of these parameters, which seems to bring further evidence for the existence of a cosmic neutrino background. In this work, we investigate the robustness of this conclusion under various assumptions. We generalise the definition of an effective sound speed and viscosity speed to the case of massive neutrinos or other dark radiation components experiencing a non-relativistic transition. We show that current bounds on these effective parameters do not vary significantly when considering an arbitrary value of the particle mass, or extended cosmological models with a free effective neutrino number, dynamical dark energy or a running of the primordial spectrum tilt. We conclude that it is possible to make a robust statement about the detection of the cosmic neutrino background by CMB experiments.

Interstellar dust within the life cycle of the interstellar medium

OpenAIRE

Demyk K.

2012-01-01

Cosmic dust is omnipresent in the Universe. Its presence influences the evolution of the astronomical objects which in turn modify its physical and chemical properties. The nature of cosmic dust, its intimate coupling with its environment, constitute a rich field of research based on observations, modelling and experimental work. This review presents the observations of the different components of interstellar dust and discusses their evolution during the life cycle of the interstellar medium.

Collisions of cosmic F- and D-strings

International Nuclear Information System (INIS)

Jones, N.

2004-01-01

Recent theoretical advances and upcoming experimental measurements make the testing of generic predictions of string theory models of cosmology feasible. Brane anti-brane models of inflation within superstring theory are promising as string theory descriptions of the physics of the early universe. While varied in their construction, these models can have the generic and observable consequence that cosmic strings will be abundant in the early universe. This leads to possible detectable effects in the cosmic microwave background, gravitational wave physics and gravitational lensing. Detailed calculations of cosmic string interactions within string theory are presented, in order to distinguish these cosmic strings from those in more conventional theories; these interaction probabilities can be very different from conventional 4-dimension strings, providing the possibility of experimental tests of string theory. (authors)

Aerosols Produced by Cosmic Rays

DEFF Research Database (Denmark)

Enghoff, Martin Andreas Bødker

an experiment in order to investigate the underlying microphysical processes. The results of this experiment will help to understand whether ionization from cosmic rays, and by implication the related processes in the universe, has a direct influence on Earth’s atmosphere and climate. Since any physical...... mechanism linking cosmic rays to clouds and climate is currently speculative, there have been various suggestions of the role atmospheric ions may play; these involve any one of a number of processes from the nucleation of aerosols up to the collection processes of cloud droplets. We have chosen to start......Satellite observations have shown that the Earth’s cloud cover is strongly correlated with the galactic cosmic ray flux. While this correlation is indicative of a possible physical connection, there is currently no confirmation that a physical mechanism exists. We are therefore setting up...

Cosmic rays, clouds, and climate

DEFF Research Database (Denmark)

Marsh, N.; Svensmark, Henrik

2000-01-01

cloud radiative properties. Thus, a moderate influence on atmospheric aerosol distributions from cosmic ray ionisation would have a strong influence on the Earth's radiation budget. Historical evidence over the past 1000 years indicates that changes in climate have occurred in accord with variability......A correlation between a global average of low cloud cover and the flux of cosmic rays incident in the atmosphere has been observed during the last solar cycle. The ionising potential of Earth bound cosmic rays are modulated by the state of the heliosphere, while clouds play an important role...... in the Earth's radiation budget through trapping outgoing radiation and reflecting incoming radiation. If a physical link between these two features can be established, it would provide a mechanism linking solar activity and Earth's climate. Recent satellite observations have further revealed a correlation...

Cosmic Rays and Extensive Air Showers

CERN Document Server

Stanev, Todor

2010-01-01

We begin with a brief introduction of the cosmic ray energy spectrum and its main features. At energies higher than 105 GeV cosmic rays are detected by the showers they initiate in the atmosphere. We continues with a brief description of the energy spectrum and composition derived from air shower data.

The History of Cosmic Ray Studies after Hess

Energy Technology Data Exchange (ETDEWEB)

Grupen, Claus, E-mail: grupen@physik.uni-siegen.de

2013-06-15

The discovery of cosmic rays by Victor Hess was confirmed with balloon flights at higher altitudes by Kolhörster. Soon the interest turned into questions about the nature of cosmic rays: gamma rays or particles? Subsequent investigations have established cosmic rays as the birthplace of elementary particle physics. The 1936 Nobel prize was shared between Victor Hess and Carl Anderson. Anderson discovered the positron in a cloud chamber. The positron was predicted by Dirac several years earlier. Many new results came now from studies with cloud chambers and nuclear emulsions. Anderson and Neddermeyer saw the muon, which for some time was considered to be a candidate for the Yukawa particle responsible for nuclear binding. Lattes, Powell, Occhialini and Muirhead clarified the situation by the discovery of the charged pions in cosmic rays. Rochester and Butler found V's, which turned out to be short-lived neutral kaons decaying into a pair of charged pions. Λ's, Σ's and Ξ's were found in cosmic rays using nuclear emulsions. After that period, accelerators and storage rings took over. The unexpected renaissance of cosmic rays started with the search for solar neutrinos and the observation of the supernova 1987A and other accelerators in the sky. With the observation of neutrino oscillations one began to look beyond the standard model of elementary particles. After 100 years of cosmic ray research we are again at the beginning of a new era, and cosmic rays may contribute to solve the many open questions, like dark matter and dark energy, by providing energies well beyond those of earth-bound accelerators.

Reading the metal diaries of the universe : tracing cosmic chemical evolution from the reionization epoch till the present

NARCIS (Netherlands)

Vink, J.

2009-01-01

Metals are essential for star formation and their subsequent evolution, and ultimately the formation of planets and the development of life, as we know it. Reconstructing the cosmic history of metals, reaching from the first population of stars to the processes involved in the formation of galaxies

COSMOS: the COsmic-ray Soil Moisture Observing System

Directory of Open Access Journals (Sweden)

M. Zreda

2012-11-01

Full Text Available The newly-developed cosmic-ray method for measuring area-average soil moisture at the hectometer horizontal scale is being implemented in the COsmic-ray Soil Moisture Observing System (or the COSMOS. The stationary cosmic-ray soil moisture probe measures the neutrons that are generated by cosmic rays within air and soil and other materials, moderated by mainly hydrogen atoms located primarily in soil water, and emitted to the atmosphere where they mix instantaneously at a scale of hundreds of meters and whose density is inversely correlated with soil moisture. The COSMOS has already deployed more than 50 of the eventual 500 cosmic-ray probes, distributed mainly in the USA, each generating a time series of average soil moisture over its horizontal footprint, with similar networks coming into existence around the world. This paper is written to serve a community need to better understand this novel method and the COSMOS project. We describe the cosmic-ray soil moisture measurement method, the instrument and its calibration, the design, data processing and dissemination used in the COSMOS project, and give example time series of soil moisture obtained from COSMOS probes.

ABIOTIC OXYGEN-DOMINATED ATMOSPHERES ON TERRESTRIAL HABITABLE ZONE PLANETS

International Nuclear Information System (INIS)

Wordsworth, Robin; Pierrehumbert, Raymond

2014-01-01

Detection of life on other planets requires identification of biosignatures, i.e., observable planetary properties that robustly indicate the presence of a biosphere. One of the most widely accepted biosignatures for an Earth-like planet is an atmosphere where oxygen is a major constituent. Here we show that lifeless habitable zone terrestrial planets around any star type may develop oxygen-dominated atmospheres as a result of water photolysis, because the cold trap mechanism that protects H 2 O on Earth is ineffective when the atmospheric inventory of non-condensing gases (e.g., N 2 , Ar) is low. Hence the spectral features of O 2 and O 3 alone cannot be regarded as robust signs of extraterrestrial life

High-energy cosmic-ray acceleration

OpenAIRE

Bustamante, M; Carrillo Montoya, G; de Paula, W; Duarte Chavez, J A; Gago, A M; Hakobyan, H; Jez, P; Monroy Montañez, J A; Ortiz Velasquez, A; Padilla Cabal, F; Pino Rozas, M; Rodriguez Patarroyo, D J; Romeo, G L; Saldaña-Salazar , U J; Velasquez, M

2010-01-01

We briefly review the basics of ultrahigh-energy cosmic-ray acceleration. The Hillas criterion is introduced as a geometrical criterion that must be fulfilled by potential acceleration sites, and energy losses are taken into account in order to obtain a more realistic scenario. The different available acceleration mechanisms are presented, with special emphasis on Fermi shock acceleration and its prediction of a power-law cosmic-ray energy spectrum. We conclude that first-order Fermi accelera...

Cosmic Rays in the Heliosphere: Requirements for Future Observations

Science.gov (United States)

Mewaldt, R. A.

2013-06-01

Since the publication of Cosmic Rays in the Heliosphere in 1998 there has been great progress in understanding how and why cosmic rays vary in space and time. This paper discusses measurements that are needed to continue advances in relating cosmic ray variations to changes in solar and interplanetary activity and variations in the local interstellar environment. Cosmic ray acceleration and transport is an important discipline in space physics and astrophysics, but it also plays a critical role in defining the radiation environment for humans and hardware in space, and is critical to efforts to unravel the history of solar activity. Cosmic rays are measured directly by balloon-borne and space instruments, and indirectly by ground-based neutron, muon and neutrino detectors, and by measurements of cosmogenic isotopes in ice cores, tree-rings, sediments, and meteorites. The topics covered here include: what we can learn from the deep 2008-2009 solar minimum, when cosmic rays reached the highest intensities of the space era; the implications of 10Be and 14C isotope archives for past and future solar activity; the effects of variations in the size of the heliosphere; opportunities provided by the Voyagers for discovering the origin of anomalous cosmic rays and measuring cosmic-ray spectra in interstellar space; and future space missions that can continue the exciting exploration of the heliosphere that has occurred over the past 50 years.

Cosmic Shear With ACS Pure Parallels

Science.gov (United States)

Rhodes, Jason

2002-07-01

Small distortions in the shapes of background galaxies by foreground mass provide a powerful method of directly measuring the amount and distribution of dark matter. Several groups have recently detected this weak lensing by large-scale structure, also called cosmic shear. The high resolution and sensitivity of HST/ACS provide a unique opportunity to measure cosmic shear accurately on small scales. Using 260 parallel orbits in Sloan textiti {F775W} we will measure for the first time: beginlistosetlength sep0cm setlengthemsep0cm setlengthopsep0cm em the cosmic shear variance on scales Omega_m^0.5, with signal-to-noise {s/n} 20, and the mass density Omega_m with s/n=4. They will be done at small angular scales where non-linear effects dominate the power spectrum, providing a test of the gravitational instability paradigm for structure formation. Measurements on these scales are not possible from the ground, because of the systematic effects induced by PSF smearing from seeing. Having many independent lines of sight reduces the uncertainty due to cosmic variance, making parallel observations ideal.

High-energy cosmic rays

Energy Technology Data Exchange (ETDEWEB)

Gaisser, Thomas K. [Bartol Research Institute, University of Delaware, Newark, DE 19716 (United States)]. E-mail: gaisser@bartol.udel.edu; Stanev, Todor [Bartol Research Institute, University of Delaware, Newark, DE 19716 (United States)

2006-10-17

After a brief review of galactic cosmic rays in the GeV to TeV energy range, we describe some current problems of interest for particles of very high energy. Particularly interesting are two features of the spectrum, the knee above 10{sup 15} eV and the ankle above 10{sup 18} eV. An important question is whether the highest-energy particles are of extra-galactic origin and, if so, at what energy the transition occurs. A theme common to all energy ranges is use of nuclear abundances as a tool for understanding the origin of the cosmic radiation.

Educational Cosmic Ray Arrays

International Nuclear Information System (INIS)

Soluk, R. A.

2006-01-01

In the last decade a great deal of interest has arisen in using sparse arrays of cosmic ray detectors located at schools as a means of doing both outreach and physics research. This approach has the unique advantage of involving grade school students in an actual ongoing experiment, rather then a simple teaching exercise, while at the same time providing researchers with the basic infrastructure for installation of cosmic ray detectors. A survey is made of projects in North America and Europe and in particular the ALTA experiment at the University of Alberta which was the first experiment operating under this paradigm

The absence of distortion in the cosmic microwave background spectrum and superconducting cosmic strings

International Nuclear Information System (INIS)

Sanchez, N.; Signore, M.

1990-01-01

From the results of recent measurements we place new constraints on superconducting cosmic strings (SCS) and on their cosmological evolution, independently of numerical simulation results. The absence of distortion in the cosmic microwave background radiation (MBR) spectrum recently reported from the preliminary data of the COBE (Cosmic background explorer) satellite, together with the available MBR angular temperature ΔT/T measurements and the latest fast pulsar timings, allow us to obtain (i) the electromagnetic-to-gravitational radiation ratio released by SCS loops, f -2 , (ii) the chemical potential due to SCS, μ 0SCS -3 , (iii) constraints on the loop evolution parameters which we confront to those given by numerical simulations, and (iv) limits on the string parameter Gμ: those obtained from COBE's data (Gμ -6 ) converge to those given by the latest PSR 1937+21 timing. Both limits on Gμ are reduced by an order of magnitude when taking into account numerical simulation results. (orig.)

Long-term and transient time variation of cosmic ray fluxes detected in Argentina by CARPET cosmic ray detector

Science.gov (United States)

De Mendonça, R. R. S.; Raulin, J.-P.; Bertoni, F. C. P.; Echer, E.; Makhmutov, V. S.; Fernandez, G.

2011-07-01

We present results obtained at El Leoncito (CASLEO, San Juan, Argentina) with the CARPET charged particles detector installed in April 2006. The observed modulation of the cosmic ray flux is discussed as a function of its time variability and it is related to longer solar activity variations and to shorter variations during solar and geomagnetic transient activity. Short period (few minutes, few hours) cosmic ray modulation events are observed during rain time (precipitation) and significant variations of the atmospheric electric field. Complementary observations of the atmospheric electric field indicate that its time variations play an important role in the detected cosmic ray event.

The ALTA cosmic ray experiment electronics system

International Nuclear Information System (INIS)

Brouwer, W.; Burris, W.J.; Caron, B.; Hewlett, J.; Holm, L.; Hamilton, A.; McDonald, W.J.; Pinfold, J.L.; Price, P.; Schaapman, J.R.; Sibley, L.; Soluk, R.A.; Wampler, L.J.

2005-01-01

Understanding the origin and propagation of high-energy cosmic rays is a fundamental area of astroparticle physics with major unanswered questions. The study of cosmic rays with energy more than 10 14 eV, probed only by ground-based experiments, has been restricted by the low particle flux. The Alberta Large-area Time-coincidence Array (ALTA) uses a sparse array of cosmic ray detection stations located in high schools across a large geographical area to search for non-random high-energy cosmic ray phenomena. Custom-built ALTA electronics is based on a modular board design. Its function is to control the detectors at each ALTA site allowing precise measurements of event timing and energy in the local detectors as well as time synchronization of all of the sites in the array using the global positioning system

Radiation chemistry and origins of life on earth

International Nuclear Information System (INIS)

Zagorski, Z. P.

2001-01-01

The role of radiation chemical processes in prebiotic time of earth history and their influence on arise of organic life on Earth has been discussed. The formation of chiral compounds in prebiotic s oup' and its further evolution for creation of bioorganic molecules was also presented and discussed as an alternative of existing hypothesis of cosmic origin of biologic life in the Earth

Voids and the Cosmic Web: cosmic depression & spatial complexity

NARCIS (Netherlands)

van de Weygaert, Rien; Shandarin, S.; Saar, E.; Einasto, J.

2016-01-01

Voids form a prominent aspect of the Megaparsec distribution of galaxies and matter. Not only do theyrepresent a key constituent of the Cosmic Web, they also are one of the cleanest probesand measures of global cosmological parameters. The shape and evolution of voids are highly sensitive tothe

Can cosmic shear shed light on low cosmic microwave background multipoles?

Science.gov (United States)

Kesden, Michael; Kamionkowski, Marc; Cooray, Asantha

2003-11-28

The lowest multipole moments of the cosmic microwave background (CMB) are smaller than expected for a scale-invariant power spectrum. One possible explanation is a cutoff in the primordial power spectrum below a comoving scale of k(c) approximately equal to 5.0 x 10(-4) Mpc(-1). Such a cutoff would increase significantly the cross correlation between the large-angle CMB and cosmic-shear patterns. The cross correlation may be detectable at >2sigma which, combined with the low CMB moments, may tilt the balance between a 2sigma result and a firm detection of a large-scale power-spectrum cutoff. The cutoff also increases the large-angle cross correlation between the CMB and the low-redshift tracers of the mass distribution.

Muon Production in Relativistic Cosmic-Ray Interactions

OpenAIRE

Klein, Spencer

2009-01-01

Cosmic-rays with energies up to $3\\times10^{20}$ eV have been observed. The nuclear composition of these cosmic rays is unknown but if the incident nuclei are protons then the corresponding center of mass energy is $\\sqrt{s_{nn}} = 700$ TeV. High energy muons can be used to probe the composition of these incident nuclei. The energy spectra of high-energy ($>$ 1 TeV) cosmic ray induced muons have been measured with deep underground or under-ice detectors. These muons come from pion and kaon de...

High energy cosmic rays: sources and fluxes

Energy Technology Data Exchange (ETDEWEB)

Stanev, Todor; Gaisser, Thomas K.; Tilav, Serap

2014-04-01

We discuss the production of a unique energy spectrum of the high energy cosmic rays detected with air showers by shifting the energy estimates of different detectors. After such a spectrum is generated we fit the spectrum with three or four populations of cosmic rays that might be accelerated at different cosmic ray sources. We also present the chemical composition that the fits of the spectrum generates and discuss some new data sets presented this summer at the ICRC in Rio de Janeiro that may require new global fits.

Measurements of Background Gamma Radiation on Some Localities of North-East Kosovo

OpenAIRE

, G. Hodolli; , Y. Halimi; , R. Gashi; , Se. Kadiri; , B. Xhafa; , A. Jonuzaj

2016-01-01

The measurement of natural environmental radiations is one of the most important subjects in health physics. The main sources of background radiation are cosmic, terrestrial and cosmogenic radiation produced by reactions with cosmic rays and atmospheric nuclei. Terrestrial radiation varies in different regions in the world. Generally the background dose rate from cosmic rays depends on the latitude and altitude. The dose rate range obtained in some northeast Kosovo, the dose rate varies from ...

Ultra high-energy cosmic ray composition

International Nuclear Information System (INIS)

Longley, N.P.

1993-01-01

The Soudan 2 surface-underground cosmic ray experiment can simultaneously measure surface shower size, underground muon multiplicity, and underground muon separation for ultra high energy cosmic ray showers. These measurements are sensitive to the primary composition. Analysis for energies from 10 1 to 10 4 TeV favors a light flux consisting of predominantly H and He nuclei

Cosmic-ray exposure records and origins of meteorites

International Nuclear Information System (INIS)

Reedy, R.C.

1985-01-01

The cosmic-ray records of meteorites can be used to infer much about their origins and recent histories. Some meteorites had simple cosmic-ray exposure histories, while others had complex exposure histories with their cosmogenic products made both before and after a collision in space. The methods used to interpret meteorites' cosmic-ray records, especially identifying simple or complex exposure histories, often are inadequate. Besides spallogenic radionuclides and stable nuclides, measurements of products that have location-sensitive production rates, such as the tracks of heavy cosmic-ray nuclei or neutron-capture nuclides, are very useful in accurately determining a meteorite's history. Samples from different, known locations of a meteorite help in studying the cosmic-ray record. Such extensive sets of meteorite measurements, plus theoretical modeling of complex histories, will improve our ability to predict the production of cosmogenic nuclides in meteorites, to distinguish simple and complex exposure histories, and to better determine exposure ages

Ultrahigh Energy Cosmic Rays: Facts, Myths, and Legends

CERN Document Server

Anchordoqui, Luis Alfredo

2013-06-27

This is a written version of a series of lectures aimed at graduate students in astrophysics/particle theory/particle experiment. In the first part, we explain the important progress made in recent years towards understanding the experimental data on cosmic rays with energies > 10^8 GeV. We begin with a brief survey of the available data, including a description of the energy spectrum, mass composition, and arrival directions. At this point we also give a short overview of experimental techniques. After that, we introduce the fundamentals of acceleration and propagation in order to discuss the conjectured nearby cosmic ray sources, and emphasize some of the prospects for a new (multi-particle) astronomy. Next, we survey the state of the art regarding the ultrahigh energy cosmic neutrinos which should be produced in association with the observed cosmic rays. In the second part, we summarize the phenomenology of cosmic ray air showers. We explain the hadronic interaction models used to extrapolate results from ...

Cosmic string induced CMB maps

International Nuclear Information System (INIS)

Landriau, M.; Shellard, E. P. S.

2011-01-01

We compute maps of CMB temperature fluctuations seeded by cosmic strings using high resolution simulations of cosmic strings in a Friedmann-Robertson-Walker universe. We create full-sky, 18 deg. and 3 deg. CMB maps, including the relevant string contribution at each resolution from before recombination to today. We extract the angular power spectrum from these maps, demonstrating the importance of recombination effects. We briefly discuss the probability density function of the pixel temperatures, their skewness, and kurtosis.

Cosmic Ray Physics with the IceCube Observatory

International Nuclear Information System (INIS)

Kolanoski, H

2013-01-01

The IceCube Neutrino Observatory with its 1-km 3 in-ice detector and the 1-km 2 surface detector (IceTop) constitutes a three-dimensional cosmic ray detector well suited for general cosmic ray physics. Various measurements of cosmic ray properties, such as energy spectra, mass composition and anisotropies, have been obtained from analyses of air showers at the surface and/or atmospheric muons in the ice.

Interpreting the cosmic ray composition

Energy Technology Data Exchange (ETDEWEB)

O' C Drury, L.; Ellisson, D.C; Meyer, J.-P

2000-01-31

The detailed pattern of elemental abundances in the Galactic Cosmic Rays is well determined at energies of a few GeV per nucleon. After correction for propagation effects the inferred source composition shows significant deviations from the standard pattern of Galactic elemental abundances. These deviations, surprisingly overabundances of the heavy elements relative to Hydrogen, are clearly a significant clue to the origin of the cosmic rays, but one which has proven very difficult to interpret. We have recently shown that the 'standard' model for the origin of the bulk of the Galactic cosmic rays, namely acceleration by the diffusive shock acceleration process at the strong shocks associated with supernova remnants, can quantitatively explain all features of the source composition if the acceleration occurs from a dusty interstellar medium. This success must be regarded as one of the stronger pieces of evidence in favour of the standard model.

Cosmic Ray Energetics and Mass

CERN Multimedia

Baylon cardiel, J L; Wallace, K C; Anderson, T B; Copley, M

The cosmic-ray energetics and mass (CREAM) investigation is designed to measure cosmic-ray composition to the supernova energy scale of 10$^{15}$ eV in a series of ultra long duration balloon (ULDB) flights. The first flight is planned to be launched from Antarctica in December 2004. The goal is to observe cosmic-ray spectral features and/or abundance changes that might signify a limit to supernova acceleration. The particle ($\\{Z}$) measurements will be made with a timing-based charge detector and a pixelated silicon charge detector to minimize the effect of backscatter from the calorimeter. The particle energy measurements will be made with a transition radiation detector (TRD) for $\\{Z}$ > 3 and a sampling tungsten/scintillator calorimeter for $\\{Z}$ $\\geq$1 particles, allowing inflight cross calibration of the two detectors. The status of the payload construction and flight preparation are reported in this paper.

Interpreting the cosmic ray composition

International Nuclear Information System (INIS)

O'C Drury, L.; Ellisson, D.C; Meyer, J.-P.

2000-01-01

The detailed pattern of elemental abundances in the Galactic Cosmic Rays is well determined at energies of a few GeV per nucleon. After correction for propagation effects the inferred source composition shows significant deviations from the standard pattern of Galactic elemental abundances. These deviations, surprisingly overabundances of the heavy elements relative to Hydrogen, are clearly a significant clue to the origin of the cosmic rays, but one which has proven very difficult to interpret. We have recently shown that the 'standard' model for the origin of the bulk of the Galactic cosmic rays, namely acceleration by the diffusive shock acceleration process at the strong shocks associated with supernova remnants, can quantitatively explain all features of the source composition if the acceleration occurs from a dusty interstellar medium. This success must be regarded as one of the stronger pieces of evidence in favour of the standard model

An ESA Robotic Package to Search for Life on Mars

Science.gov (United States)

Westall, F.; Brack, A.; Clancy, P.; Hofmann, B.; Horneck, G.; Kurat, G.; Maxwell, J.; Ori, G. G.; Pillinger, C.; Raulin, F.

1999-01-01

Similarities in the early histories of Mars and Earth suggest that life may have arisen on Mars as it did on Earth. The early life forms on Mars were probably simple organisms, similar to terrestrial prokaryotes. In fact, given the early deterioration of the Martian climate, it is unlikely that life on Mars could ever have reached more sophisticated evolution. Based on the present knowledge of Mars, the possibility of extant life at the surface is small. However, given the adaptability of terrestrial prokaryotes under adverse conditions, it is not excluded. Any extant life is hypothesized to reside in the permafrost in a dormant state until "reanimated" by impact-caused hydrothermal activity. Using this rationale, a group of European scientists worked together to conceive a hypothetical strategy to search for life on Mars. A possible configuration for a lander/rover is outlined.

Cosmic Heritage Evolution from the Big Bang to Conscious Life

CERN Document Server

Shaver, Peter

2011-01-01

This book follows the evolutionary trail all the way from the Big Bang 13.7 billion years ago to conscious life today. It is an accessible introductory book written for the interested layperson – anyone interested in the ‘big picture’ coming from modern science. It covers a wide range of topics including the origin and evolution of our universe, the nature and origin of life, the evolution of life including questions of birth and death, the evolution of cognition, the nature of consciousness, the possibility of extraterrestrial life and the future of the universe. The book is written in a narrative style, as these topics are all parts of a single story. It concludes with a discussion on the nature and future of science.  “Peter Shaver has written engagingly for anyone curious about the world we inhabit.  If you'd like to know how the Universe began, where the chemical elements originated, how life may have started on Earth, how man, ants and bacteria are related to each other, or why we humans think...

Cosmic gamma bursts

International Nuclear Information System (INIS)

Ehstulin, I.V.

1980-01-01

A brief consideration is being given to the history of cosmic gamma burst discovery and modern knowledge of their properties. The time dependence of gamma bursts is described and their possible sources are discussed

Structure formation cosmic rays: Identifying observational constraints

Directory of Open Access Journals (Sweden)

Prodanović T.

2005-01-01

Full Text Available Shocks that arise from baryonic in-fall and merger events during the structure formation are believed to be a source of cosmic rays. These "structure formation cosmic rays" (SFCRs would essentially be primordial in composition, namely, mostly made of protons and alpha particles. However, very little is known about this population of cosmic rays. One way to test the level of its presence is to look at the products of hadronic reactions between SFCRs and the ISM. A perfect probe of these reactions would be Li. The rare isotope Li is produced only by cosmic rays, dominantly in αα → 6Li fusion reactions with the ISM helium. Consequently, this nuclide provides a unique diagnostic of the history of cosmic rays. Exactly because of this unique property is Li affected most by the presence of an additional cosmic ray population. In turn, this could have profound consequences for the Big-Bang nucleosynthesis: cosmic rays created during cosmic structure formation would lead to pre-Galactic Li production, which would act as a "contaminant" to the primordial 7Li content of metalpoor halo stars. Given the already existing problem of establishing the concordance between Li observed in halo stars and primordial 7Li as predicted by the WMAP, it is crucial to set limits to the level of this "contamination". However, the history of SFCRs is not very well known. Thus we propose a few model-independent ways of testing the SFCR species and their history, as well as the existing lithium problem: 1 we establish the connection between gamma-ray and Li production, which enables us to place constraints on the SFCR-made lithium by using the observed Extragalactic Gamma-Ray Background (EGRB; 2 we propose a new site for testing the primordial and SFCR-made lithium, namely, low-metalicity High-Velocity Clouds (HVCs, which retain the pre-Galactic composition without any significant depletion. Although using one method alone may not give us strong constraints, using them in

14. European cosmic ray symposium. Symposium program and abstracts

International Nuclear Information System (INIS)

1994-08-01

The abstracts of the 14. European Cosmic Ray Symposium are presented. The papers cover a large variety of topics in cosmic ray physics, both from the theoretical and the experimental point of view. Sun physics, and the effects on the inner heliosphere, the composition, and the properties of the primary and secondary cosmic radiation, galactic acceleration and the results of accelerator physics relevant to cosmic radiation physics, and the description and the results of large detector systems are presented. 63 items are indexed for INIS database. (K.A.)

Cosmic Censorship for Gowdy Spacetimes.

Science.gov (United States)

Ringström, Hans

2010-01-01

Due to the complexity of Einstein's equations, it is often natural to study a question of interest in the framework of a restricted class of solutions. One way to impose a restriction is to consider solutions satisfying a given symmetry condition. There are many possible choices, but the present article is concerned with one particular choice, which we shall refer to as Gowdy symmetry. We begin by explaining the origin and meaning of this symmetry type, which has been used as a simplifying assumption in various contexts, some of which we shall mention. Nevertheless, the subject of interest here is strong cosmic censorship. Consequently, after having described what the Gowdy class of spacetimes is, we describe, as seen from the perspective of a mathematician, what is meant by strong cosmic censorship. The existing results on cosmic censorship are based on a detailed analysis of the asymptotic behavior of solutions. This analysis is in part motivated by conjectures, such as the BKL conjecture, which we shall therefore briefly describe. However, the emphasis of the article is on the mathematical analysis of the asymptotics, due to its central importance in the proof and in the hope that it might be of relevance more generally. The article ends with a description of the results that have been obtained concerning strong cosmic censorship in the class of Gowdy spacetimes.

How to detect the cosmic neutrino background?

International Nuclear Information System (INIS)

Ringwald, A.

2003-01-01

A measurement of the big bang relic neutrinos would open a new window to the early universe. We review various possibilities to detect this cosmic neutrino background and substantiate the assertion that - apart from the rather indirect evidence to be gained from cosmology and large-scale structure formation - the annihilation of ultrahigh energy cosmic neutrinos with relic anti-neutrinos (or vice versa) on the Z-resonance is a unique process having sensitivity to the relic neutrinos, if a sufficient flux at E ν i res =M Z 2 /(2m ν i )=4.10 22 eV (0.1 eV/m ν i ) exists. The associated absorption dips in the ultrahigh energy cosmic neutrino spectrum may be searched for at forthcoming neutrino and air shower detectors. The associated protons and photons may have been seen already in form of the cosmic ray events above the Greisen-Zatsepin-Kuzmin cutoff. (orig.)

Comparing cosmic web classifiers using information theory

Energy Technology Data Exchange (ETDEWEB)

Leclercq, Florent [Institute of Cosmology and Gravitation (ICG), University of Portsmouth, Dennis Sciama Building, Burnaby Road, Portsmouth PO1 3FX (United Kingdom); Lavaux, Guilhem; Wandelt, Benjamin [Institut d' Astrophysique de Paris (IAP), UMR 7095, CNRS – UPMC Université Paris 6, Sorbonne Universités, 98bis boulevard Arago, F-75014 Paris (France); Jasche, Jens, E-mail: florent.leclercq@polytechnique.org, E-mail: lavaux@iap.fr, E-mail: j.jasche@tum.de, E-mail: wandelt@iap.fr [Excellence Cluster Universe, Technische Universität München, Boltzmannstrasse 2, D-85748 Garching (Germany)

2016-08-01

We introduce a decision scheme for optimally choosing a classifier, which segments the cosmic web into different structure types (voids, sheets, filaments, and clusters). Our framework, based on information theory, accounts for the design aims of different classes of possible applications: (i) parameter inference, (ii) model selection, and (iii) prediction of new observations. As an illustration, we use cosmographic maps of web-types in the Sloan Digital Sky Survey to assess the relative performance of the classifiers T-WEB, DIVA and ORIGAMI for: (i) analyzing the morphology of the cosmic web, (ii) discriminating dark energy models, and (iii) predicting galaxy colors. Our study substantiates a data-supported connection between cosmic web analysis and information theory, and paves the path towards principled design of analysis procedures for the next generation of galaxy surveys. We have made the cosmic web maps, galaxy catalog, and analysis scripts used in this work publicly available.

Comparing cosmic web classifiers using information theory

International Nuclear Information System (INIS)

Leclercq, Florent; Lavaux, Guilhem; Wandelt, Benjamin; Jasche, Jens

2016-01-01

We introduce a decision scheme for optimally choosing a classifier, which segments the cosmic web into different structure types (voids, sheets, filaments, and clusters). Our framework, based on information theory, accounts for the design aims of different classes of possible applications: (i) parameter inference, (ii) model selection, and (iii) prediction of new observations. As an illustration, we use cosmographic maps of web-types in the Sloan Digital Sky Survey to assess the relative performance of the classifiers T-WEB, DIVA and ORIGAMI for: (i) analyzing the morphology of the cosmic web, (ii) discriminating dark energy models, and (iii) predicting galaxy colors. Our study substantiates a data-supported connection between cosmic web analysis and information theory, and paves the path towards principled design of analysis procedures for the next generation of galaxy surveys. We have made the cosmic web maps, galaxy catalog, and analysis scripts used in this work publicly available.

Cosmic microwave background theory

Science.gov (United States)

Bond, J. Richard

1998-01-01

A long-standing goal of theorists has been to constrain cosmological parameters that define the structure formation theory from cosmic microwave background (CMB) anisotropy experiments and large-scale structure (LSS) observations. The status and future promise of this enterprise is described. Current band-powers in ℓ-space are consistent with a ΔT flat in frequency and broadly follow inflation-based expectations. That the levels are ∼(10−5)2 provides strong support for the gravitational instability theory, while the Far Infrared Absolute Spectrophotometer (FIRAS) constraints on energy injection rule out cosmic explosions as a dominant source of LSS. Band-powers at ℓ ≳ 100 suggest that the universe could not have re-ionized too early. To get the LSS of Cosmic Background Explorer (COBE)-normalized fluctuations right provides encouraging support that the initial fluctuation spectrum was not far off the scale invariant form that inflation models prefer: e.g., for tilted Λ cold dark matter sequences of fixed 13-Gyr age (with the Hubble constant H0 marginalized), ns = 1.17 ± 0.3 for Differential Microwave Radiometer (DMR) only; 1.15 ± 0.08 for DMR plus the SK95 experiment; 1.00 ± 0.04 for DMR plus all smaller angle experiments; 1.00 ± 0.05 when LSS constraints are included as well. The CMB alone currently gives weak constraints on Λ and moderate constraints on Ωtot, but theoretical forecasts of future long duration balloon and satellite experiments are shown which predict percent-level accuracy among a large fraction of the 10+ parameters characterizing the cosmic structure formation theory, at least if it is an inflation variant. PMID:9419321

Isotherms clustering in cosmic microwave background

International Nuclear Information System (INIS)

Bershadskii, A.

2006-01-01

Isotherms clustering in cosmic microwave background (CMB) has been studied using the 3-year WMAP data on cosmic microwave background radiation. It is shown that the isotherms clustering could be produced by the baryon-photon fluid turbulence in the last scattering surface. The Taylor-microscale Reynolds number of the turbulence is estimated directly from the CMB data as Re λ ∼10 2

Cosmic censorship, black holes, and particle orbits

International Nuclear Information System (INIS)

Hiscock, W.A.

1979-01-01

One of the main reasons for believing in the cosmic censorship hypothesis is the disquieting nature of the alternative: the existence of naked singularities, and hence loss of predictability, the possibility of closed timelike lines and so forth. The consequences of assuming the cosmic hypothesis can also be somewhat strange and unexpected. In particular, Hawking's black hole area theorem is applied to the study of particle orbits near a Schwarzschild black hole. If the cosmic censorship hypothesis (and hence the area theorem) is true, then there exist stable near-circular orbits arbitrarily close to the horizon at r = 2M. (author)

Cosmic-ray antimatter - A primary origin hypothesis

Science.gov (United States)

Stecker, F. W.; Protheroe, R. J.; Kazanas, D.

1983-01-01

The present investigation is concerned with the possibility that the observed cosmic-ray protons are of primary extragalactic origin, taking into account the significance of the current antiproton data. Attention is given to questions regarding primary antiprotons, antihelium fluxes, and the propagation of extragalactic cosmic rays. It is concluded that the primary origin hypothesis should be considered as a serious alternative explanation for the cosmic-ray antiproton fluxes. Such extragalactic primary origin can be considered in the context of a baryon symmetric domain cosmology. The fluxes and propagation characteristics suggested are found to be in rough agreement with the present antiproton data.

Wavelet-Bayesian inference of cosmic strings embedded in the cosmic microwave background

Science.gov (United States)

McEwen, J. D.; Feeney, S. M.; Peiris, H. V.; Wiaux, Y.; Ringeval, C.; Bouchet, F. R.

2017-12-01

Cosmic strings are a well-motivated extension to the standard cosmological model and could induce a subdominant component in the anisotropies of the cosmic microwave background (CMB), in addition to the standard inflationary component. The detection of strings, while observationally challenging, would provide a direct probe of physics at very high-energy scales. We develop a framework for cosmic string inference from observations of the CMB made over the celestial sphere, performing a Bayesian analysis in wavelet space where the string-induced CMB component has distinct statistical properties to the standard inflationary component. Our wavelet-Bayesian framework provides a principled approach to compute the posterior distribution of the string tension Gμ and the Bayesian evidence ratio comparing the string model to the standard inflationary model. Furthermore, we present a technique to recover an estimate of any string-induced CMB map embedded in observational data. Using Planck-like simulations, we demonstrate the application of our framework and evaluate its performance. The method is sensitive to Gμ ∼ 5 × 10-7 for Nambu-Goto string simulations that include an integrated Sachs-Wolfe contribution only and do not include any recombination effects, before any parameters of the analysis are optimized. The sensitivity of the method compares favourably with other techniques applied to the same simulations.

Cosmic strings in a braneworld theory with metastable gravitons

International Nuclear Information System (INIS)

Lue, Arthur

2002-01-01

If the graviton possesses an arbitrarily small (but nonvanishing) mass, perturbation theory implies that cosmic strings have a nonzero Newtonian potential. Nevertheless in Einstein gravity, where the graviton is strictly massless, the Newtonian potential of a cosmic string vanishes. This discrepancy is an example of the van Dam-Veltman-Zakharov (VDVZ) discontinuity. We present a solution for the metric around a cosmic string in a braneworld theory with a graviton metastable on the brane. This theory possesses those features that yield a VDVZ discontinuity in massive gravity, but nevertheless is generally covariant and classically self-consistent. Although the cosmic string in this theory supports a nontrivial Newtonian potential far from the source, one can recover the Einstein solution in a region near the cosmic string. That latter region grows as the graviton's effective linewidth vanishes (analogous to a vanishing graviton mass), suggesting the lack of a VDVZ discontinuity in this theory. Moreover, the presence of scale dependent structure in the metric may have consequences for the search for cosmic strings through gravitational lensing techniques

Current constraints on the cosmic growth history

International Nuclear Information System (INIS)

Bean, Rachel; Tangmatitham, Matipon

2010-01-01

We present constraints on the cosmic growth history with recent cosmological data, allowing for deviations from ΛCDM as might arise if cosmic acceleration is due to modifications to general relativity or inhomogeneous dark energy. We combine measures of the cosmic expansion history, from Type 1a supernovae, baryon acoustic oscillations, and the cosmic microwave background (CMB), with constraints on the growth of structure from recent galaxy, CMB, and weak lensing surveys along with integated Sachs Wolfe-galaxy cross correlations. Deviations from ΛCDM are parameterized by phenomenological modifications to the Poisson equation and the relationship between the two Newtonian potentials. We find modifications that are present at the time the CMB is formed are tightly constrained through their impact on the well-measured CMB acoustic peaks. By contrast, constraints on late-time modifications to the growth history, as might arise if modifications are related to the onset of cosmic acceleration, are far weaker, but remain consistent with ΛCDM at the 95% confidence level. For these late-time modifications we find that differences in the evolution on large and small scales could provide an interesting signature by which to search for modified growth histories with future wide angular coverage, large scale structure surveys.

Xenia: A Probe of Cosmic Chemical Evolution

Science.gov (United States)

Kouveliotou, Chryssa; Piro, L.

2008-01-01

Xenia is a concept study for a medium-size astrophysical cosmology mission addressing the Cosmic Origins key objective of NASA's Science Plan. The fundamental goal of this objective is to understand the formation and evolution of structures on various scales from the early Universe to the present time (stars, galaxies and the cosmic web). Xenia will use X-and y-ray monitoring and wide field X-ray imaging and high-resolution spectroscopy to collect essential information from three major tracers of these cosmic structures: the Warm Hot Intergalactic Medium (WHIM), Galaxy Clusters and Gamma Ray Bursts (GRBs). Our goal is to trace the chemo-dynamical history of the ubiquitous warm hot diffuse baryon component in the Universe residing in cosmic filaments and clusters of galaxies up to its formation epoch (at z =0-2) and to map star formation and galaxy metal enrichment into the re-ionization era beyond z 6. The concept of Xenia (Greek for "hospitality") evolved in parallel with the Explorer of Diffuse Emission and GRB Explosions (EDGE), a mission proposed by a multinational collaboration to the ESA Cosmic Vision 2015. Xenia incorporates the European and Japanese collaborators into a U.S. led mission that builds on the scientific objectives and technological readiness of EDGE.

Xenia: A Probe of Cosmic Chemical Evolution

Science.gov (United States)

Kouveliotou, Chryssa; Piro, L.; Xenia Collaboration

2008-03-01

Xenia is a concept study for a medium-size astrophysical cosmology mission addressing the Cosmic Origins key objective of NASA's Science Plan. The fundamental goal of this objective is to understand the formation and evolution of structures on various scales from the early Universe to the present time (stars, galaxies and the cosmic web). Xenia will use X-and γ-ray monitoring and wide field X-ray imaging and high-resolution spectroscopy to collect essential information from three major tracers of these cosmic structures: the Warm Hot Intergalactic Medium (WHIM), Galaxy Clusters and Gamma Ray Bursts (GRBs). Our goal is to trace the chemo-dynamical history of the ubiquitous warm hot diffuse baryon component in the Universe residing in cosmic filaments and clusters of galaxies up to its formation epoch (at z =0-2) and to map star formation and galaxy metal enrichment into the re-ionization era beyond z 6. The concept of Xenia (Greek for "hospitality") evolved in parallel with the Explorer of Diffuse Emission and GRB Explosions (EDGE), a mission proposed by a multinational collaboration to the ESA Cosmic Vision 2015. Xenia incorporates the European and Japanese collaborators into a U.S. led mission that builds on the scientific objectives and technological readiness of EDGE.

The Cosmic Ray Tracking (CRT) detector system

International Nuclear Information System (INIS)

Bernloehr, K.; Gamp, S.; Hermann, G.; Hofmann, W.; Kihm, T.; Knoeppler, J.; Leffers, G.; Matheis, V.; Panter, M.; Trunk, U.; Ulrich, M.; Wolf, T.; Zink, R.; Heintze, J.

1996-01-01

The Cosmic Ray Tracking (CRT) project represents a study on the use of tracking detectors of the time projection chamber type to detect secondary cosmic ray particles in extensive air showers. In reconstructing the arrival direction of the primary cosmic ray particles, the CRT detectors take advantage of the angular correlation of secondary particles with the cosmic rays leading to these air showers. In this paper, the detector hardware including the custom-designed electronics system is described in detail. A CRT detector module provides an active area of 2.5 m 2 and allows to measure track directions with a precision of 0.4 circle . It consists of two circular drift chambers of 1.8 m diameter with six sense wires each, and a 10 cm thick iron plate between the two chambers. Each detector has a local electronics box with a readout, trigger, and monitoring system. The detectors can distinguish penetrating muons from other types of charged secondaries. A large detector array could be used to search for γ-ray point sources at energies above several TeV and for studies of the cosmic-ray composition. Ten detectors are in operation at the site of the HEGRA air shower array. (orig.)

Exploring the cosmic evolution of habitability with galaxy merger trees

Science.gov (United States)

Stanway, E. R.; Hoskin, M. J.; Lane, M. A.; Brown, G. C.; Childs, H. J. T.; Greis, S. M. L.; Levan, A. J.

2018-04-01

We combine inferred galaxy properties from a semi-analytic galaxy evolution model incorporating dark matter halo merger trees with new estimates of supernova and gamma-ray burst rates as a function of metallicity from stellar population synthesis models incorporating binary interactions. We use these to explore the stellar-mass fraction of galaxies irradiated by energetic astrophysical transients and its evolution over cosmic time, and thus the fraction which is potentially habitable by life like our own. We find that 18 per cent of the stellar mass in the Universe is likely to have been irradiated within the last 260 Myr, with GRBs dominating that fraction. We do not see a strong dependence of irradiated stellar-mass fraction on stellar mass or richness of the galaxy environment. We consider a representative merger tree as a Local Group analogue, and find that there are galaxies at all masses which have retained a high habitable fraction (>40 per cent) over the last 6 Gyr, but also that there are galaxies at all masses where the merger history and associated star formation have rendered galaxies effectively uninhabitable. This illustrates the need to consider detailed merger trees when evaluating the cosmic evolution of habitability.

Life in the lithosphere, kinetics and the prospects for life elsewhere.

Science.gov (United States)

Cockell, Charles S

2011-02-13

The global contiguity of life on the Earth today is a result of the high flux of carbon and oxygen from oxygenic photosynthesis over the planetary surface and its use in aerobic respiration. Life's ability to directly use redox couples from components of the planetary lithosphere in a pre-oxygenic photosynthetic world can be investigated by studying the distribution of organisms that use energy sources normally bound within rocks, such as iron. Microbiological data from Iceland and the deep oceans show the kinetic limitations of living directly off igneous rocks in the lithosphere. Using energy directly extracted from rocks the lithosphere will support about six orders of magnitude less productivity than the present-day Earth, and it would be highly localized. Paradoxically, the biologically extreme conditions of the interior of a planet and the inimical conditions of outer space, between which life is trapped, are the locations from which volcanism and impact events, respectively, originate. These processes facilitate the release of redox couples from the planetary lithosphere and might enable it to achieve planetary-scale productivity approximately one to two orders of magnitude lower than that produced by oxygenic photosynthesis. The significance of the detection of extra-terrestrial life is that it will allow us to test these observations elsewhere and establish an understanding of universal relationships between lithospheres and life. These data also show that the search for extra-terrestrial life must be accomplished by 'following the kinetics', which is different from following the water or energy.

Solar-terrestrial disturbances in June-September 1982, 5

International Nuclear Information System (INIS)

Ondoh, Tadanori

1985-01-01

The x-ray detector on the SMS-GOES satellite observed 77 solar x-ray flares (1 - 8A) with flux above 10 -5 W/m 2 in June, 1982, and 33 SIDs with importance above 2 were observed in Hiraiso, Japan. However, the geomagnetic storm with Dst above 100 nT did not occur at that time since most solar flares occurred near the east rim of the sun. These solar active regions lasted for 5 solar rotations, then, the great geomagnetic storms with Dst above 100 nT occurred on July 13 - 15, September 5 - 7 and September 21 - 23, 1982. These geomagnetic storms were preceded by the solar flares of importance above 2B occurred in the central part of the solar disc. From September 26 to 27, 1982, a great geomagnetic storm which was not accompanied by solar flare occurred. This paper summarized the studies on solar-terrestrial events from June to September, 1982, made by the space physics and aeronomy groups of the Radio Research Laboratories, Japan. The solar flares occurred on July 12, September 4 and 19, 1982, the geomagnetic storms corresponding to them, the cosmic ray storms observed on July 13 - 19, September 6 - 9 and 21 - 26, 1982, global equivalent current system and others are reported. (Kako, I.)

The Cosmic Microwave Background Anisotropy

Science.gov (United States)

Bennett, C. L.

1994-12-01

The properties of the cosmic microwave background radiation provide unique constraints on the history and evolution of the universe. The first detection of anisotropy of the microwave radiation was reported by the COBE Team in 1992, based on the first year of flight data. The latest analyses of the first two years of COBE data are reviewed in this talk, including the amplitude of the microwave anisotropy as a function of angular scale and the statistical nature of the fluctuations. The two-year results are generally consistent with the earlier first year results, but the additional data allow for a better determination of the key cosmological parameters. In this talk the COBE results are compared with other observational anisotropy results and directions for future cosmic microwave anisotropy observations will be discussed. The National Aeronautics and Space Administration/Goddard Space Flight Center (NASA/GSFC) is responsible for the design, development, and operation of the Cosmic Background Explorer (COBE). Scientific guidance is provided by the COBE Science Working Group.

Search for antimatter in 1012 eV cosmic rays using Artemis method and interpretation of the cosmic rays spectrum

International Nuclear Information System (INIS)

Pomarede, D.

1999-04-01

This thesis is divided into three parts. The first part is a review of the present knowledge of the antimatter and of the cosmic rays. Theoretical and experimental aspects are presented. It is demonstrated that a measurement of the antimatter abundance in TeV cosmic rays is of fundamental interest, and would establish the symmetric or asymmetric nature of the Universe. The second part is dedicated to the method of antimatter research through the Earth Moon ion spectrometer (ARTEMIS). The account is given of the winter 1996-97 41-nights observation campaign undertaken at the Whipple Observatory in Arizona (USA). A 109 photomultiplier camera is operated on the 40 meter telescope to detect by Cherenkov imaging the cosmic ray initiated showers. We describe the performance of an optical filter used to reduce the noise. The development and the utilization of a simulation program are described. The main work is the analysis of the data: data characterization, understanding of the apparatus, understanding of the noise and its influence, calibration, search for signals by different methods. Subtle systematic effects are uncovered. The simulations establish that the amount of data is insufficient to reveal a shadow effect in the cosmic ray flux. The conclusion of this work is that the experimental setup was not suitable, and we propose important improvements of the method based on a bigger focal plane that would allow to reach a one percent sensitivity on the antimatter content of the cosmic rays. In the third part of the thesis, an interpretation of the total cosmic ray spectrum is proposed and discussed. (author)

Cosmic-ray exposure records and origins of meteorites

International Nuclear Information System (INIS)

Reedy, R.C.

1985-01-01

The cosmic-ray records of meteorites are used to infer much about their origins and recent histories. The methods used to interpret meteorites cosmic-ray records, especially identifying simple or complex exposure histories, often are inadequate. Spallogenic radionuclides, stable nuclides, and measurements of products that have location-sensitive production rates, such as the tracks of heavy cosmic-ray nuclei or neutron-capture nuclides, are very useful in accurately determining a meteorite's history. Samples from different, known locations of a meteorite help in studying the cosmic-ray record. Such extensive sets of meteorite measuremetns, plus theoretical modeling of complex histories, improves the ability to predict the production of cosmogenic nuclides in meteorites, to distinguish simple and complex exposure histories, and to better determine exposure ages

Interstellar propagation of low energy cosmic rays

International Nuclear Information System (INIS)

Cesarsky, C.J.

1975-01-01

Wave particles interactions prevent low energy cosmic rays from propagating at velocities much faster than the Alfven velocity, reducing their range by a factor of order 50. Therefore, supernovae remnants cannot fill the neutral portions of the interstellar medium with 2 MeV cosmic rays [fr

Cosmic radiation doses at flight level altitudes of airliners

International Nuclear Information System (INIS)

Viragh, E.; Petr, I.

1985-01-01

Changes are discussed in flux density of cosmic radiation particles with time as are the origin of cosmic radiation, the level of cosmic radiation near the Earth's surface, and the determination of cosmic radiation doses in airliners. Doses and dose rates are given measured on different flight routes. In spite of the fact that the flight duration at an altitude of about 10 km makes for about 80% of the total flight time, the overall radiation burden of the crews at 1000 flight hours a year is roughly double that of the rest of the population. (J.C.)

Standard Cosmic Ray Energetics and Light Element Production

CERN Document Server

Fields, B D; Cassé, M; Vangioni-Flam, E; Fields, Brian D.; Olive, Keith A.; Casse, Michel; Vangioni-Flam, Elisabeth

2001-01-01

The recent observations of Be and B in metal poor stars has led to a reassessment of the origin of the light elements in the early Galaxy. At low it is metallicity ([O/H] < -1.75), it is necessary to introduce a production mechanism which is independent of the interstellar metallicity (primary). At higher metallicities, existing data might indicate that secondary production is dominant. In this paper, we focus on the secondary process, related to the standard Galactic cosmic rays, and we examine the cosmic ray energy requirements for both present and past epochs. We find the power input to maintain the present-day Galactic cosmic ray flux is about 1.5e41 erg/s = 5e50 erg/century. This implies that, if supernovae are the sites of cosmic ray acceleration, the fraction of explosion energy going to accelerated particles is about 30%, a value which we obtain consistently both from considering the present cosmic ray flux and confinement and from the present 9Be and 6Li abundances. Using the abundances of 9Be (an...

Relative distribution of cosmic rays and magnetic fields

Science.gov (United States)

Seta, Amit; Shukurov, Anvar; Wood, Toby S.; Bushby, Paul J.; Snodin, Andrew P.

2018-02-01

Synchrotron radiation from cosmic rays is a key observational probe of the galactic magnetic field. Interpreting synchrotron emission data requires knowledge of the cosmic ray number density, which is often assumed to be in energy equipartition (or otherwise tightly correlated) with the magnetic field energy. However, there is no compelling observational or theoretical reason to expect such a tight correlation to hold across all scales. We use test particle simulations, tracing the propagation of charged particles (protons) through a random magnetic field, to study the cosmic ray distribution at scales comparable to the correlation scale of the turbulent flow in the interstellar medium (≃100 pc in spiral galaxies). In these simulations, we find that there is no spatial correlation between the cosmic ray number density and the magnetic field energy density. In fact, their distributions are approximately statistically independent. We find that low-energy cosmic rays can become trapped between magnetic mirrors, whose location depends more on the structure of the field lines than on the field strength.

George Smoot, Blackbody, and Anisotropy of the Cosmic Microwave Background

Science.gov (United States)

the Cosmic Microwave Background Radiation Resources with Additional Information * Videos 'George Smoot anisotropy of the cosmic microwave background radiation." '1 Smoot previously won the Ernest Orlando . Smoot, blackbody, and anisotropy of the Cosmic Microwave Background (CMB) radiation is available in full

Cosmic Rays Astrophysics: The Discipline, Its Scope, and Its Applications

Science.gov (United States)

Barghouty, A. F.

2009-01-01

This slide presentation gives an overview of the discipline surrounding cosmic ray astrophysics. It includes information on recent assertions surrounding cosmic rays, exposure levels, and a short history with specific information on the origin, acceleration, transport, and modulation of cosmic rays.

Theory of geomagnetic effects of cosmic rays: its past and presence

Energy Technology Data Exchange (ETDEWEB)

Gall, R [Universidad Nacional Autonoma de Mexico, Mexico City. Inst. de Geofisica

1981-03-01

The interest expressed by Lemaitre and Vallarta in the nature of universal corpuscular radiation, remnant of the exploded primogenitive atom, culminated in 1932, in the development of their theory of the geomagnetic effects of cosmic rays, a tool since its publication, basic to cosmic radiation research and to the advancement of cosmic ray astronomy. Between 1940 and 1960 challenging experimental data from proliferating cosmic radiation stations and of direct detection techniques provided geomagnetic field models for greater theoretical precision. The discoveries since the advent of the space age of the Earth's cavity and geomagnetic tail, and of the nonrelativistic solar cosmic rays have resulted in a new branch of the theory dealing with magnetosphere effects in the propagation of low energy cosmic radiations. The theory's importance and application to cosmic bodies other than the Earth is discussed.

Cosmic Dawn with WFIRST

Science.gov (United States)

Rhoads, James

Central objectives: WFIRST-AFTA has tremendous potential for studying the epoch of "Cosmic Dawn" the period encompassing the formation of the first galaxies and quasars, and their impact on the surrounding universe through cosmological reionization. Our goal is to ensure that this potential is realized through the middle stages of mission planning, culminating in designs for both WFIRST and its core surveys that meet the core objectives in dark energy and exoplanet science, while maximizing the complementary Cosmic Dawn science. Methods: We will consider a combined approach to studying Cosmic Dawn using a judicious mixture of guest investigator data analysis of the primary WFIRST surveys, and a specifically designed Guest Observer program to complement those surveys. The Guest Observer program will serve primarily to obtain deep field observations, with particular attention to the capabilities of WFIRST for spectroscopic deep fields using the WFI grism. We will bring to bear our years of experience with slitless spectroscopy on the Hubble Space Telescope, along with an expectation of JWST slitless grism spectroscopy. We will use this experience to examine the implications of WFIRST’s grism resolution and wavelength coverage for deep field observations, and if appropriate, to suggest potential modifications of these parameters to optimize the science return on WFIRST. We have assembled a team of experts specializing in (1) Lyman Break Galaxies at redshifts higher than 7 (2) Quasars at high redshifts (3) Lyman-alpha galaxies as probes of reionization (4) Theoretical simulations of high-redshift galaxies (5) Simulations of grism observations (6) post-processing analysis to find emission line galaxies and high redshift galaxies (7) JWST observations and calibrations. With this team we intend to do end-to-end simulations starting with halo populations and expected spectra of high redshift galaxies and finally extracting what we can learn about (a) reionization

Th/U/Pu/Cm dating of galactic cosmic rays with the extremely heavy cosmic ray composition observer

Science.gov (United States)

Westphal, Andrew J.; Weaver, Benjamin A.; Tarlé, Gregory

The principal goal of ECCO, the Extremely-heavy Cosmic-ray Composition Observer, is the measurement of the age of heavy galactic cosmic-ray nuclei using the extremely rare actinides (Th, U, Pu, Cm) as clocks. ECCO is one of two cosmic-ray instruments comprising the Heavy Nuclei Explorer (HNX), which was recently selected as one of several missions for Phase A study under NASA's Small class Explorer (SMEX) program. ECCO is based on the flight heritage of Trek, an array of barium-phosphate glass tracketch detectors deployed on the Russian space station Mir from 1991-1995. Using Trek, we measured the abundances of elements with Z > 70 in the galactic cosmic rays (GCRs). Trek consisted of a 1 m 2 array of stacks of individually polished thin BP-1 glass detectors. ECCO will be a much larger instrument, but will achieve both excellent resolution and low cost through use of a novel detector configuration. Here we report the results of recent accelerator tests of the ECCO detectors that verify detector performance. We also show the expected charge and energy resolution of ECCO as a function of energy.

Measurement of cosmic-ray reconstruction efficiencies in the MicroBooNE LArTPC using a small external cosmic-ray counter

Science.gov (United States)

Acciarri, R.; Adams, C.; An, R.; Anthony, J.; Asaadi, J.; Auger, M.; Bagby, L.; Balasubramanian, S.; Baller, B.; Barnes, C.; Barr, G.; Bass, M.; Bay, F.; Bishai, M.; Blake, A.; Bolton, T.; Camilleri, L.; Caratelli, D.; Carls, B.; Castillo Fernandez, R.; Cavanna, F.; Chen, H.; Church, E.; Cianci, D.; Cohen, E.; Collin, G. H.; Conrad, J. M.; Convery, M.; Crespo-Anadón, J. I.; Del Tutto, M.; Devitt, D.; Dytman, S.; Eberly, B.; Ereditato, A.; Escudero Sanchez, L.; Esquivel, J.; Fadeeva, A. A.; Fleming, B. T.; Foreman, W.; Furmanski, A. P.; Garcia-Gamez, D.; Garvey, G. T.; Genty, V.; Goeldi, D.; Gollapinni, S.; Graf, N.; Gramellini, E.; Greenlee, H.; Grosso, R.; Guenette, R.; Hackenburg, A.; Hamilton, P.; Hen, O.; Hewes, J.; Hill, C.; Ho, J.; Horton-Smith, G.; Hourlier, A.; Huang, E.-C.; James, C.; de Vries, J. Jan; Jen, C.-M.; Jiang, L.; Johnson, R. A.; Joshi, J.; Jostlein, H.; Kaleko, D.; Kalousis, L. N.; Karagiorgi, G.; Ketchum, W.; Kirby, B.; Kirby, M.; Kobilarcik, T.; Kreslo, I.; Lange, G.; Laube, A.; Li, Y.; Lister, A.; Littlejohn, B. R.; Lockwitz, S.; Lorca, D.; Louis, W. C.; Luethi, M.; Lundberg, B.; Luo, X.; Marchionni, A.; Mariani, C.; Marshall, J.; Martinez Caicedo, D. A.; Meddage, V.; Miceli, T.; Mills, G. B.; Moon, J.; Mooney, M.; Moore, C. D.; Mousseau, J.; Murrells, R.; Naples, D.; Nienaber, P.; Nowak, J.; Palamara, O.; Paolone, V.; Papavassiliou, V.; Pate, S. F.; Pavlovic, Z.; Pelkey, R.; Piasetzky, E.; Porzio, D.; Pulliam, G.; Qian, X.; Raaf, J. L.; Rafique, A.; Rochester, L.; von Rohr, C. Rudolf; Russell, B.; Schmitz, D. W.; Schukraft, A.; Seligman, W.; Shaevitz, M. H.; Sinclair, J.; Smith, A.; Snider, E. L.; Soderberg, M.; Söldner-Rembold, S.; Soleti, S. R.; Spentzouris, P.; Spitz, J.; John, J. St.; Strauss, T.; Szelc, A. M.; Tagg, N.; Terao, K.; Thomson, M.; Toups, M.; Tsai, Y.-T.; Tufanli, S.; Usher, T.; Van De Pontseele, W.; Van de Water, R. G.; Viren, B.; Weber, M.; Wickremasinghe, D. A.; Wolbers, S.; Wongjirad, T.; Woodruff, K.; Yang, T.; Yates, L.; Zeller, G. P.; Zennamo, J.; Zhang, C.

2017-12-01

The MicroBooNE detector is a liquid argon time projection chamber at Fermilab designed to study short-baseline neutrino oscillations and neutrino-argon interaction cross-section. Due to its location near the surface, a good understanding of cosmic muons as a source of backgrounds is of fundamental importance for the experiment. We present a method of using an external 0.5 m (L) × 0.5 m (W) muon counter stack, installed above the main detector, to determine the cosmic-ray reconstruction efficiency in MicroBooNE. Data are acquired with this external muon counter stack placed in three different positions, corresponding to cosmic rays intersecting different parts of the detector. The data reconstruction efficiency of tracks in the detector is found to be epsilondata=(97.1±0.1 (stat) ± 1.4 (sys))%, in good agreement with the Monte Carlo reconstruction efficiency epsilonMC = (97.4±0.1)%. This analysis represents a small-scale demonstration of the method that can be used with future data coming from a recently installed cosmic-ray tagger system, which will be able to tag ≈80% of the cosmic rays passing through the MicroBooNE detector.

Cosmic ray electrons and protons, and their antiparticles

International Nuclear Information System (INIS)

Boezio, Mirko

2014-01-01

Cosmic rays are a sample of solar, galactic, and extragalactic matter. Their origin, acceleration mechanisms, and subsequent propagation toward Earth have intrigued scientists since their discovery. These issues can be studied via analysis of the energy spectra and composition of cosmic rays. Protons are the most abundant component of the cosmic radiation, and many experiments have been dedicated to the accurate measurement of their spectra. Complementary information is provided by electrons, which comprise about 1% of the cosmic radiation. Because of their low mass, electrons experience severe energy losses through synchrotron emission in the galactic magnetic field and inverse Compton scattering of radiation fields. Electrons therefore provide information on the local galactic environment that is not accessible from the study of the cosmic ray nuclei. Antiparticles, namely antiprotons and positrons, are produced in the interaction between cosmic ray nuclei and the interstellar matter. They are therefore intimately linked to the propagation mechanisms of the parent nuclei. Novel sources of primary cosmic ray antiparticles of either astrophysical (e.g., positrons from pulsars) or exotic origin (e.g., annihilation of dark matter particles) may exist. The nature of dark matter is one of the most prominent open questions in science today. An observation of positrons from pulsars would open a new observation window on these sources. Several experiments equipped with state-of-the art detector systems have recently presented results on the energy spectra of electrons, protons, and their antiparticles with a significant improvement in statistics and better control of systematics The status of the field will be reviewed, with a focus on these recent scientific results. (author)

Radar detection of ultra high energy cosmic rays

Science.gov (United States)

Myers, Isaac J.

TARA (Telescope Array Radar) is a cosmic ray radar detection experiment co-located with Telescope Array, the conventional surface scintillation detector (SD) and fluorescence telescope detector (FD) near Delta, UT. The TARA detector combines a 40 kW transmitter and high gain transmitting antenna which broadcasts the radar carrier over the SD array and in the FD field of view to a 250 MS/s DAQ receiver. Data collection began in August, 2013. TARA stands apart from other cosmic ray radar experiments in that radar data is directly compared with conventional cosmic ray detector events. The transmitter is also directly controlled by TARA researchers. Waveforms from the FD-triggered data stream are time-matched with TA events and searched for signal using a novel signal search technique in which the expected (simulated) radar echo of a particular air shower is used as a matched filter template and compared to radio waveforms. This technique is used to calculate the radar cross-section (RCS) upper-limit on all triggers that correspond to well-reconstructed TA FD monocular events. Our lowest cosmic ray RCS upper-limit is 42 cm2 for an 11 EeV event. An introduction to cosmic rays is presented with the evolution of detection and the necessity of new detection techniques, of which radar detection is a candidate. The software simulation of radar scattering from cosmic rays follows. The TARA detector, including transmitter and receiver systems, are discussed in detail. Our search algorithm and methodology for calculating RCS is presented for the purpose of being repeatable. Search results are explained in context of the usefulness and future of cosmic ray radar detection.

Anomalous isotopic composition of cosmic rays

International Nuclear Information System (INIS)

Woosley, S.E.; Weaver, T.A.

1980-01-01

Recent measurements of nonsolar isotopic patterns for the elements neon and (perhaps) magnesium in cosmic rays are interpreted within current models of stellar nucleosynthesis. One possible explanation is that the stars currently responsible for cosmic-ray synthesis in the Galaxy are typically super-metal-rich by a factor of two to three. Other possibilities include the selective acceleration of certain zones or masses of supernovas or the enhancement of 22 Ne in the interstellar medium by mass loss from red giant stars and planetary nebulas. Measurements of critical isotopic ratios are suggested to aid in distinguishing among the various possibilities. Some of these explanations place significant constraints on the fraction of cosmic ray nuclei that must be fresh supernova debris and the masses of the supernovas involved. 1 figure, 3 tables

Cosmic microwave background bispectrum from recombination.

Science.gov (United States)

Huang, Zhiqi; Vernizzi, Filippo

2013-03-08

We compute the cosmic microwave background temperature bispectrum generated by nonlinearities at recombination on all scales. We use CosmoLib2nd, a numerical Boltzmann code at second order to compute cosmic microwave background bispectra on the full sky. We consistently include all effects except gravitational lensing, which can be added to our result using standard methods. The bispectrum is peaked on squeezed triangles and agrees with the analytic approximation in the squeezed limit at the few percent level for all the scales where this is applicable. On smaller scales, we recover previous results on perturbed recombination. For cosmic-variance limited data to l(max)=2000, its signal-to-noise ratio is S/N=0.47, corresponding to f(NL)(eff)=-2.79, and will bias a local signal by f(NL)(loc) ~/= 0.82.

The propagation of galactic cosmic rays

International Nuclear Information System (INIS)

Hall, A.N.

1981-01-01

Large scale (approximately 15 pc) turbulence in the interstellar medium (ISM) causes the firehose and mirror instabilities to occur. These produce small scale (approximately 10 -7 pc) magnetic irregularities, which scatter cosmic rays. We use pulsar scintillation data, and a model of the origin of these scintillations, to construct a slab model of the turbulent ISM. Then we find the amplitudes and wavelengths of the magnetic irregularities that arise, and we calculate the coefficients for the diffusion of cosmic rays along the interstellar magnetic fields. We incorporate this diffusion into our model of the turbulent ISM, and show that it can account naturally for both the lifetime of low energy cosmic rays, and the variation of their mean pathlength with energy. Our model has no galactic halo, and contains no scattering by Alfven waves. (author)

Cosmic-ray modulation: an ab initio approach

Energy Technology Data Exchange (ETDEWEB)

Engelbrecht, N.E.; Burger, R.A., E-mail: 12580996@nwu.ac.za [Center for Space Research, North-West University, Potchefstroom (South Africa)

2014-07-01

A better understanding of cosmic-ray modulation in the heliosphere can only be gained through a proper understanding of the effects of turbulence on the diffusion and drift of cosmic rays. We present an ab initio model for cosmic-ray modulation, incorporating for the first time the results yielded by a two-component turbulence transport model. This model is solved for periods of minimum solar activity, utilizing boundary values chosen so that model results are in fair to good agreement with spacecraft observations of turbulence quantities, not only in the solar ecliptic plane but also along the out-of-ecliptic trajectory of the Ulysses spacecraft. These results are employed as inputs for modelled slab and 2D turbulence energy spectra. The latter spectrum is chosen based on physical considerations, with a drop-off at the very lowest wavenumbers commencing at the 2D outerscale. There currently exist no models or observations for this quantity, and it is the only free parameter in this study. The modelled turbulence spectra are used as inputs for parallel mean free path expressions based on those derived from quasi-linear theory and perpendicular mean free paths from extended nonlinear guiding center theory. Furthermore, the effects of turbulence on cosmic-ray drifts are modelled in a self-consistent way, employing a recently developed model for drift along the wavy current sheet. The resulting diffusion coefficients and drift expressions are applied to the study of galactic cosmic-ray protons and antiprotons using a three dimensional, steady-state cosmic-ray modulation code, and sample solutions in fair agreement with multiple spacecraft observations are presented. (author)

Cosmic-ray modulation: an ab initio approach

International Nuclear Information System (INIS)

Engelbrecht, N.E.; Burger, R.A.

2014-01-01

A better understanding of cosmic-ray modulation in the heliosphere can only be gained through a proper understanding of the effects of turbulence on the diffusion and drift of cosmic rays. We present an ab initio model for cosmic-ray modulation, incorporating for the first time the results yielded by a two-component turbulence transport model. This model is solved for periods of minimum solar activity, utilizing boundary values chosen so that model results are in fair to good agreement with spacecraft observations of turbulence quantities, not only in the solar ecliptic plane but also along the out-of-ecliptic trajectory of the Ulysses spacecraft. These results are employed as inputs for modelled slab and 2D turbulence energy spectra. The latter spectrum is chosen based on physical considerations, with a drop-off at the very lowest wavenumbers commencing at the 2D outerscale. There currently exist no models or observations for this quantity, and it is the only free parameter in this study. The modelled turbulence spectra are used as inputs for parallel mean free path expressions based on those derived from quasi-linear theory and perpendicular mean free paths from extended nonlinear guiding center theory. Furthermore, the effects of turbulence on cosmic-ray drifts are modelled in a self-consistent way, employing a recently developed model for drift along the wavy current sheet. The resulting diffusion coefficients and drift expressions are applied to the study of galactic cosmic-ray protons and antiprotons using a three dimensional, steady-state cosmic-ray modulation code, and sample solutions in fair agreement with multiple spacecraft observations are presented. (author)

The basis for cosmic ray feedback: Written on the wind

Science.gov (United States)

Zweibel, Ellen G.

2017-05-01

Star formation and supermassive black hole growth in galaxies appear to be self-limiting. The mechanisms for self-regulation are known as feedback. Cosmic rays, the relativistic particle component of interstellar and intergalactic plasma, are among the agents of feedback. Because cosmic rays are virtually collisionless in the plasma environments of interest, their interaction with the ambient medium is primarily mediated by large scale magnetic fields and kinetic scale plasma waves. Because kinetic scales are much smaller than global scales, this interaction is most conveniently described by fluid models. In this paper, I discuss the kinetic theory and the classical theory of cosmic ray hydrodynamics (CCRH) which follows from assuming cosmic rays interact only with self-excited waves. I generalize CCRH to generalized cosmic ray hydrodynamics, which accommodates interactions with extrinsic turbulence, present examples of cosmic ray feedback, and assess where progress is needed.

ATLAS and ultra high energy cosmic ray physics

Directory of Open Access Journals (Sweden)

Pinfold James

2017-01-01

Full Text Available After a brief introduction to extended air shower cosmic ray physics the current and future deployment of forward detectors at ATLAS is discussed along with the various aspects of the current and future ATLAS programs to explore hadronic physics. The emphasis is placed on those results and future plans that have particular relevance for high-energy, and ultra high-energy, cosmic ray physics. The possible use of ATLAS as an “underground” cosmic muon observatory is briefly considered.

Delayed recombination and cosmic parameters

International Nuclear Information System (INIS)

Galli, Silvia; Melchiorri, Alessandro; Bean, Rachel; Silk, Joseph

2008-01-01

Current cosmological constraints from cosmic microwave background anisotropies are typically derived assuming a standard recombination scheme, however additional resonance and ionizing radiation sources can delay recombination, altering the cosmic ionization history and the cosmological inferences drawn from the cosmic microwave background data. We show that for recent observations of the cosmic microwave background anisotropy, from the Wilkinson microwave anisotropy probe satellite mission (WMAP) 5-year survey and from the arcminute cosmology bolometer array receiver experiment, additional resonance radiation is nearly degenerate with variations in the spectral index, n s , and has a marked effect on uncertainties in constraints on the Hubble constant, age of the universe, curvature and the upper bound on the neutrino mass. When a modified recombination scheme is considered, the redshift of recombination is constrained to z * =1078±11, with uncertainties in the measurement weaker by 1 order of magnitude than those obtained under the assumption of standard recombination while constraints on the shift parameter are shifted by 1σ to R=1.734±0.028. From the WMAP5 data we obtain the following constraints on the resonance and ionization sources parameters: ε α i <0.058 at 95% c.l.. Although delayed recombination limits the precision of parameter estimation from the WMAP satellite, we demonstrate that this should not be the case for future, smaller angular scales measurements, such as those by the Planck satellite mission.

Gamma-ray astronomy and cosmic-ray origin theory

International Nuclear Information System (INIS)

Ginzburg, V.L.

1973-01-01

A theory of the origin of cosmic radiation is discussed in light of the advances made in gamma-ray astronomy. Arguments against metagalactic models for the origin of cosmic rays are emphasized. (U.S.)

Gene Expression Dynamics in Major Endocrine Regulatory Pathways along the Transition from Solitary to Social Life in a Bumblebee, Bombus terrestris

Directory of Open Access Journals (Sweden)

Pavel Jedlička

2016-11-01

Full Text Available Understanding the social evolution leading to insect eusociality requires, among other, a detailed insight into endocrine regulatory mechanisms that have been co-opted from solitary ancestors to play new roles in the complex life histories of eusocial species. Bumblebees represent well-suited models of a relatively primitive social organization standing on the mid-way to highly advanced eusociality and their queens undergo both, a solitary and a social phase, separated by winter diapause.In the present paper, we characterize the gene expression levels of major endocrine regulatory pathways across tissues, sexes, and life-stages of the buff-tailed bumblebee, Bombus terrestris, with special emphasis on critical stages of the queen’s transition from solitary to social life. We focused on fundamental genes of three pathways: (1 Forkhead box protein O and insulin/insulin-like signaling, (2 Juvenile hormone signaling, and (3 Adipokinetic hormone signaling. Virgin queens were distinguished by higher expression of forkhead box protein O and downregulated insulin-like peptides and juvenile hormone (JH signaling, indicated by low expression of methyl farnesoate epoxidase (MFE and transcription factor Krüppel homolog 1 (Kr-h1. Diapausing queens showed the expected downregulation of JH signaling in terms of low MFE and vitellogenin (Vg expressions, but an unexpectedly high expression of Kr-h1. By contrast, reproducing queens revealed an upregulation of MFE and Vg together with insulin signaling. Surprisingly, the insulin growth factor 1 (IGF-1 turned out to be a queen-specific hormone. Workers exhibited an expression pattern of MFE and Vg similar to that of reproducing queens. Males were characterized by high Kr-h1 expression and low Vg level. The tissue comparison unveiled an unexpected resemblance between the fat body and hypopharyngeal glands across all investigated genes, sexes, and life stages.

Cosmic Rays in Thunderstorms

Science.gov (United States)

Buitink, Stijn; Scholten, Olaf; van den Berg, Ad; Ebert, Ute

2013-04-01

Cosmic Rays in Thunderstorms Cosmic rays are protons and heavier nuclei that constantly bombard the Earth's atmosphere with energies spanning a vast range from 109 to 1021 eV. At typical altitudes up to 10-20 km they initiate large particle cascades, called extensive air showers, that contain millions to billions of secondary particles depending on their initial energy. These particles include electrons, positrons, hadrons and muons, and are concentrated in a compact particle front that propagates at relativistic speed. In addition, the shower leaves behind a trail of lower energy electrons from ionization of air molecules. Under thunderstorm conditions these electrons contribute to the electrical and ionization processes in the cloud. When the local electric field is strong enough the secondary electrons can create relativistic electron run-away avalanches [1] or even non-relativistic avalanches. Cosmic rays could even trigger lightning inception. Conversely, strong electric fields also influence the development of the air shower [2]. Extensive air showers emit a short (tens of nanoseconds) radio pulse due to deflection of the shower particles in the Earth's magnetic field [3]. Antenna arrays, such as AERA, LOFAR and LOPES detect these pulses in a frequency window of roughly 10-100 MHz. These systems are also sensitive to the radiation from discharges associated to thunderstorms, and provide a means to study the interaction of cosmic ray air showers and the electrical processes in thunderstorms [4]. In this presentation we discuss the involved radiation mechanisms and present analyses of thunderstorm data from air shower arrays [1] A. Gurevich et al., Phys. Lett. A 165, 463 (1992) [2] S. Buitink et al., Astropart. Phys. 33, 1 (2010) [3] H. Falcke et al., Nature 435, 313 (2005) [4] S. Buitink et al., Astron. & Astrophys. 467, 385 (2007)

Half a century of cosmic x-ray research

International Nuclear Information System (INIS)

Makishima, Kazuo; Takahashi, Tadayuki

2012-01-01

The year of 2012, which is the centennial of the cosmic-ray discovery, happens to coincide with the 50th anniversary of the discovery of cosmic X-ray sources. First carried by cosmic-ray physicists, the study of cosmic X-rays has made explosive developments over the last half a century, and has established the X-ray wavelength as an indispensable window onto the Universe. Among a variety of X-ray emitting celestial objects, we choose here neutron stars as a representative, and review the 50 years connecting the dawn era of the research and the state-of-the-art ASTRO-H satellite to be launched in 2014. In this article, 'X-rays' mean energetic photons with energies from 0.1 keV up to a few hundreds keV. (author)

Cosmic ray acceleration by large scale galactic shocks

International Nuclear Information System (INIS)

Cesarsky, C.J.; Lagage, P.O.

1987-01-01

The mechanism of diffusive shock acceleration may account for the existence of galactic cosmic rays detailed application to stellar wind shocks and especially to supernova shocks have been developed. Existing models can usually deal with the energetics or the spectral slope, but the observed energy range of cosmic rays is not explained. Therefore it seems worthwhile to examine the effect that large scale, long-lived galactic shocks may have on galactic cosmic rays, in the frame of the diffusive shock acceleration mechanism. Large scale fast shocks can only be expected to exist in the galactic halo. We consider three situations where they may arise: expansion of a supernova shock in the halo, galactic wind, galactic infall; and discuss the possible existence of these shocks and their role in accelerating cosmic rays

Gravitational-Wave Stochastic Background from Cosmic Strings

International Nuclear Information System (INIS)

Siemens, Xavier; Creighton, Jolien; Mandic, Vuk

2007-01-01

We consider the stochastic background of gravitational waves produced by a network of cosmic strings and assess their accessibility to current and planned gravitational wave detectors, as well as to big bang nucleosynthesis (BBN), cosmic microwave background (CMB), and pulsar timing constraints. We find that current data from interferometric gravitational wave detectors, such as Laser Interferometer Gravitational Wave Observatory (LIGO), are sensitive to areas of parameter space of cosmic string models complementary to those accessible to pulsar, BBN, and CMB bounds. Future more sensitive LIGO runs and interferometers such as Advanced LIGO and Laser Interferometer Space Antenna (LISA) will be able to explore substantial parts of the parameter space

The terrestrial evolution of metabolism and life - by the numbers.

Science.gov (United States)

O'Kelly, Gregory C

2009-08-27

Allometric scaling relating body mass to metabolic rate by an exponent of the former (Kleiber's Law), commonly known as quarter-power scaling (QPS), is controversial for claims made on its behalf, especially that of its universality for all life. As originally formulated, Kleiber was based upon the study of heat; metabolic rate is quantified in watts (or calories per unit time). Techniques and technology for metabolic energy measurement have been refined but the math has not. QPS is susceptible to increasing deviations from theoretical predictions to data, suggesting that there is no single, universal exponent relevant to all of life. QPS's major proponents continue to fail to make good on hints of the power of the equation for understanding aging. ESSENTIALIST-DEDUCTIVIST VIEW: If the equation includes a term for efficiency in the exponent, thereby ruling out thermogenesis as part of metabolism, its heuristic power is greatly amplified, and testable deductive inferences are generated. If metabolic rate is measured in watts and metabolic efficiency is a redox-coupling ratio, then the equation is essentially about the energy storage capacity of organic molecules. The equation is entirely about the essentials of all life: water, salt, organic molecules, and energy. The water and salt provide an electrochemical salt bridge for the transmission of energy into and through the organic components. The equation, when graphed, treats the organic structure as battery-like, and relates its recharge rate and electrical properties to its longevity. The equation models the longevity-extending effects of caloric restriction, and shows where those effects wane. It models the immortality of some types of cells, and supports the argument for the origin of life being at submarine volcanic vents and black smokers. It clarifies how early life had to change to survive drifting to the surface, and what drove mutations in its ascent. It does not deal with cause and effect; it deals with

Sealed drift tube cosmic ray veto counters

International Nuclear Information System (INIS)

Rios, R.; Tatar, E.; Bacon, J.D.; Bowles, T.J.; Hill, R.; Green, J.A.; Hogan, G.E.; Ito, T.M.; Makela, M.; Morris, C.L.; Mortenson, R.; Pasukanics, F.E.; Ramsey, J.; Saunders, A.; Seestrom, S.J.; Sondheim, W.E.; Teasdale, W.; Saltus, M.; Back, H.O.; Cottrell, C.R.

2011-01-01

We describe a simple drift tube counter that has been used as a cosmic ray veto for the UCNA experiment, a first-ever measurement of the neutron beta-asymmetry using ultra-cold neutrons. These detectors provide an inexpensive alternative to more conventional scintillation detectors for large area cosmic ray anticoincidence detectors.

RECORD-SETTING COSMIC-RAY INTENSITIES IN 2009 AND 2010

International Nuclear Information System (INIS)

Mewaldt, R. A.; Davis, A. J.; Leske, R. A.; Stone, E. C.; Cummings, A. C.; Labrador, A. W.; Lave, K. A.; Binns, W. R.; Israel, M. H.; Wiedenbeck, M. E.; Christian, E. R.; De Nolfo, G. A.; Von Rosenvinge, T. T.

2010-01-01

We report measurements of record-setting intensities of cosmic-ray nuclei from C to Fe, made with the Cosmic Ray Isotope Spectrometer carried on the Advanced Composition Explorer in orbit about the inner Sun-Earth Lagrangian point. In the energy interval from ∼70 to ∼450 MeV nucleon -1 , near the peak in the near-Earth cosmic-ray spectrum, the measured intensities of major species from C to Fe were each 20%-26% greater in late 2009 than in the 1997-1998 minimum and previous solar minima of the space age (1957-1997). The elevated intensities reported here and also at neutron monitor energies were undoubtedly due to several unusual aspects of the solar cycle 23/24 minimum, including record-low interplanetary magnetic field (IMF) intensities, an extended period of reduced IMF turbulence, reduced solar-wind dynamic pressure, and extremely low solar activity during an extended solar minimum. The estimated parallel diffusion coefficient for cosmic-ray transport based on measured solar-wind properties was 44% greater in 2009 than in the 1997-1998 solar-minimum period. In addition, the weaker IMF should result in higher cosmic-ray drift velocities. Cosmic-ray intensity variations at 1 AU are found to lag IMF variations by 2-3 solar rotations, indicating that significant solar modulation occurs inside ∼20 AU, consistent with earlier galactic cosmic-ray radial-gradient measurements. In 2010, the intensities suddenly decreased to 1997 levels following increases in solar activity and in the inclination of the heliospheric current sheet. We describe the conditions that gave cosmic rays greater access to the inner solar system and discuss some of their implications.

Cl36 and the age of the cosmic rays

International Nuclear Information System (INIS)

Casse, M.; Goret, P.; Regnier, S.

1975-01-01

The radioactive isotope 36 Cl (tau=γx3.10 5 y) is used as a time reference for the propagation of cosmic rays. New measurements of the production cross section of 36 Cl in Ti and Fe at 24GeV will be presented. A critical analysis of the cross sections leads to an estimate of the ratio 36 Cl/Cl=0.030+0.007 in the arriving cosmic rays. The comparison between the expected abundance of Cl in the arriving cosmic rays and the observations tend to support the decay of 36 Cl. The inferred cosmic ray confinement time is about 10 6 y [fr

Oldest pathology in a tetrapod bone illuminates the origin of terrestrial vertebrates.

Directory of Open Access Journals (Sweden)

Peter J Bishop

Full Text Available The origin of terrestrial tetrapods was a key event in vertebrate evolution, yet how and when it occurred remains obscure, due to scarce fossil evidence. Here, we show that the study of palaeopathologies, such as broken and healed bones, can help elucidate poorly understood behavioural transitions such as this. Using high-resolution finite element analysis, we demonstrate that the oldest known broken tetrapod bone, a radius of the primitive stem tetrapod Ossinodus pueri from the mid-Viséan (333 million years ago of Australia, fractured under a high-force, impact-type loading scenario. The nature of the fracture suggests that it most plausibly occurred during a fall on land. Augmenting this are new osteological observations, including a preferred directionality to the trabecular architecture of cancellous bone. Together, these results suggest that Ossinodus, one of the first large (>2m length tetrapods, spent a significant proportion of its life on land. Our findings have important implications for understanding the temporal, biogeographical and physiological contexts under which terrestriality in vertebrates evolved. They push the date for the origin of terrestrial tetrapods further back into the Carboniferous by at least two million years. Moreover, they raise the possibility that terrestriality in vertebrates first evolved in large tetrapods in Gondwana rather than in small European forms, warranting a re-evaluation of this important evolutionary event.

A Bayesian framework for cosmic string searches in CMB maps

Energy Technology Data Exchange (ETDEWEB)

Ciuca, Razvan; Hernández, Oscar F., E-mail: razvan.ciuca@mail.mcgill.ca, E-mail: oscarh@physics.mcgill.ca [Department of Physics, McGill University, 3600 rue University, Montréal, QC, H3A 2T8 (Canada)

2017-08-01

There exists various proposals to detect cosmic strings from Cosmic Microwave Background (CMB) or 21 cm temperature maps. Current proposals do not aim to find the location of strings on sky maps, all of these approaches can be thought of as a statistic on a sky map. We propose a Bayesian interpretation of cosmic string detection and within that framework, we derive a connection between estimates of cosmic string locations and cosmic string tension G μ. We use this Bayesian framework to develop a machine learning framework for detecting strings from sky maps and outline how to implement this framework with neural networks. The neural network we trained was able to detect and locate cosmic strings on noiseless CMB temperature map down to a string tension of G μ=5 ×10{sup −9} and when analyzing a CMB temperature map that does not contain strings, the neural network gives a 0.95 probability that G μ≤2.3×10{sup −9}.

Maximum entropy analysis of cosmic ray composition

Czech Academy of Sciences Publication Activity Database

Nosek, D.; Ebr, Jan; Vícha, Jakub; Trávníček, Petr; Nosková, J.

2016-01-01

Roč. 76, Mar (2016), s. 9-18 ISSN 0927-6505 R&D Projects: GA ČR(CZ) GA14-17501S Institutional support: RVO:68378271 Keywords : ultra-high energy cosmic rays * extensive air showers * cosmic ray composition Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 3.257, year: 2016

Early history of cosmic rays at Chicago

Science.gov (United States)

Yodh, Gaurang B.

2013-02-01

Cosmic ray studies at the University of Chicago were started by Arthur Compton during the late 1920s. The high points of cosmic ray studies at Chicago under Compton and Marcel Schein are the focus of this report, which summarizes the research done at Chicago up to the end of World War II.

Status and Conservation Possibilities of Papua New Guinea’s Terrestrial Mammals

Directory of Open Access Journals (Sweden)

David Lopez Cornelio

2012-01-01

Full Text Available The status of Papua New Guinea’s terrestrial mammals is revised according to their geographical distribution,life history characteristics, and current conservation plans and legislation. Considering their uniqueness andthreatening factors, their appropriate management is critical to achieve sustainable development in the country.Concerning marsupial species no one has been yet domesticated, there is no organized breeding and theirnatural productivity is generally lower than ruminants. Their conservation status is related to their size assmaller species are usually more prolific, less conspicuous, and less preferred by hunters. Differences onevolutionary ecology between families are discussed, and recommendations are given for the assessment andfurther conservation of vulnerable species. Conservation programs must go alongside with rural livelihoodsimprovement through ecotourism, food security, and marketing of non timber forest products.Keywords: terrestrial mammal, marsupial spesies, conservation status, Papua New Guinea

An effective method for terrestrial arthropod euthanasia.

Science.gov (United States)

Bennie, Neil A C; Loaring, Christopher D; Bennie, Mikaella M G; Trim, Steven A

2012-12-15

As scientific understanding of invertebrate life increases, so does the concern for how to end that life in an effective way that minimises (potential) suffering and is also safe for those carrying out the procedure. There is increasing debate on the most appropriate euthanasia methods for invertebrates as their use in experimental research and zoological institutions grows. Their popularity as pet species has also led to an increase in the need for greater veterinary understanding. Through the use of a local injection of potassium chloride (KCl) initially developed for use in American lobsters, this paper describes a safe and effective method for euthanasia in terrestrial invertebrates. Initial work focused on empirically determining the dose for cockroaches, which was then extrapolated to other arthropod species. For this method of euthanasia, we propose the term 'targeted hyperkalosis' to describe death through terminal depolarisation of the thoracic ganglia as a result of high potassium concentration.

Heliospheric Impact on Cosmic Rays Modulation

Science.gov (United States)

Tiwari, Bhupendra Kumar

2016-07-01

Heliospheric Impact on Cosmic RaysModulation B. K. Tiwari Department of Physics, A. P. S. University, Rewa (M.P.), btiwari70@yahoo.com Cosmic rays (CRs) flux at earth is modulated by the heliosphereric magnetic field and the structure of the heliosphere, controls by solar outputs and their variability. Sunspots numbers (SSN) is often treated as a primary indicator of solar activity (SA). GCRs entering the helioshphere are affected by the interplanetary magnetic field (IMF) and solar wind speed, their modulation varies with the varying solar activity. The observation based on data recoded from Omniweb data Centre for solar- interplanetary activity indices and monthly mean count rate of cosmic ray intensity (CRI) data from neutron monitors of different cut-off rigidities(Rc) (Moscow Rc=2.42Gv and Oulu Rc=0.80Gv). During minimum solar activity periodof solar cycle 23/24, the sun is remarkably quiet, weakest strength of the IMF and least dense and slowest, solar wind speed, whereas, in 2003, highest value of yearly averaged solar wind speed (~568 Km/sec) associated with several coronal holes, which generate high speed wind stream has been recorded. It is observed that GCRs fluxes reduces and is high anti-correlated with SSN (0.80) and IMF (0.86). CRI modulation produces by a strong solar flare, however, CME associated solar flare produce more disturbance in the interplanetary medium as well as in geomagnetic field. It is found that count rate of cosmic ray intensity and solar- interplanetary parameters were inverse correlated and solar indices were positive correlated. Keywords- Galactic Cosmic rays (GCRs), Sunspot number (SSN), Solar activity (SA), Coronal Mass Ejection (CME), Interplanetary magnetic field (IMF)

Ultrahigh-energy particles from cosmic strings

International Nuclear Information System (INIS)

Bhattacharjee, P.

1991-02-01

The idea of production of ultrahigh-energy particles in the present universe due to annihilation or collapse of topological defects is discussed. Topological defects, formed in symmetry-breaking phase transitions in the early universe, can survive till today owing to their topological stability. However, under certain circumstances, topological defects may be physically destroyed. When topological defects are destroyed, the energy contained in the defects can be released in the form of massive gauge- and Higgs bosons of the underlying spontaneously broken gauge theory. Subsequent decay of these massive particles can give rise to energetic particles ranging up to an energy on the order of the mass of the original particles released from the defects. This may give us a ''natural'' mechanism of production of extremely energetic cosmic ray particles in the universe today, without the need for any acceleration mechanism. To illustrate this idea, I describe in detail the calculation of the expected ultrahigh-energy proton spectrum due to a specific process which involves collapse or multiple self-intersections of a class of closed cosmic string loops formed in a phase transition at a grand unification energy scale. I discuss the possibility that some of the highest-energy cosmic ray particles are of this origin. By comparing with the observational results on the ultrahigh-energy cosmic rays, we derive an upper limit to the average fraction of the total energy in all ''primary'' cosmic string loops that may be released in the form of particles due to collapse or multiple self-intersections of these loops. No nuclei such as α's or Fe's are in the spectrum. 43 refs., 3 figs

Terrestrial and marine trophic pathways support young-of-year growth in a nearshore Arctic fish

Science.gov (United States)

von Biela, Vanessa R.; Zimmerman, Christian E.; Cohn, Brian R.; Welker, Jeffrey M.

2013-01-01

River discharge supplies nearshore communities with a terrestrial carbon source that is often reflected in invertebrate and fish consumers. Recent studies in the Beaufort Sea have documented widespread terrestrial carbon use among invertebrates, but only limited use among nearshore fish consumers. Here, we examine the carbon source and diet of rapidly growing young-of-year Arctic cisco (Coregonus autumnalis) using stable isotope values (δ13C and δ15N) from muscle and diet analysis (stomach contents) during a critical and previously unsampled life stage. Stable isotope values (δ15N and δ13C) may differentiate between terrestrial and marine sources and integrate over longer time frames (weeks). Diet analysis provides species-specific information, but only from recent foraging (days). Average δ13C for all individuals was −25.7 ‰, with the smallest individuals possessing significantly depleted δ13C values indicative of a stronger reliance of terrestrial carbon sources as compared to larger individuals. Average δ15N for all individuals was 10.4 ‰, with little variation among individuals. As fish length increased, the proportion of offshore Calanus prey and neritic Mysis prey increased. Rapid young-of-year growth in Arctic cisco appears to use terrestrial carbon sources obtained by consuming a mixture of neritic and offshore zooplankton. Shifts in the magnitude or phenology of river discharge and the delivery of terrestrial carbon may alter the ecology of nearshore fish consumers.

Cosmic Times: Astronomy History and Science for the Classroom

Science.gov (United States)

Lochner, James C.; Mattson, B.

2008-05-01

Cosmic Times is a series of curriculum support materials and classroom activities for upper middle school and high school students which teach the nature of science by exploring the history of our understanding of the universe during the past 100 years. Starting with the confirmation of Einstein's theory of gravity in 1919 to the current conundrum posed by the discovery of dark energy, Cosmic Times examines the discoveries, the theories, and the people involved in this changing [understanding] of the universe. Cosmic Times takes the form of 6 posters, each resembling the front page of a newspaper from a particular time in this history with articles describing the discoveries. Each poster is accompanied by 4-5 classroom lessons which enable students to examine the science concepts behind the discoveries, develop techniques to improve science literacy, and investigate the nature of science using historical examples. Cosmic Times directly connects with the IYA theme of Astronomy in the Classroom, as well as the general theme of the impact of astronomy history. Cosmic Times has been developed with a freelance writer to write the articles for the posters, a group of teachers to develop the lessons, and evaluator to provide testing of the materials with a group of rural teachers in underserved communities. This poster presentation previews the Cosmic Times materials, which are posted on http://cosmictimes.gsfc.nasa.gov/ as they become available. Cosmic Times is funded in part via a NASA IDEAS grant.

Could the cosmic acceleration be transient?

Energy Technology Data Exchange (ETDEWEB)

Guimaraes, Antonio C.C.; Lima, J.A.S. [Universidade de Sao Paulo (IAG/USP), SP (Brazil). Inst. de Astronomia, Geofisica e Ciencias Atmosfericas

2011-07-01

Full text: The possibility of a transient cosmic acceleration appears in several theoretical scenarios and is theoretically interesting because it solves some difficulties inherent to eternally accelerating universes (like {Lambda}CDM). On the observational side, some authors, using a dynamical Ansatz for the dark energy equation of state, have suggested that the cosmic acceleration have already peaked and that we are currently witnessing its slowing down. Here, a possible slowing down of the cosmic expansion is investigated through a cosmographic approach. By expanding the luminous distance to fourth order and fitting the SNe Ia data from the most recent compilations (Union, Constitution and Union 2), the marginal likelihood distribution for the deceleration parameter today indicates that there is a considerable probability for q{sub 0} > 0. Also in contrast to the prediction of the {Lambda}CDM model, the cosmographic q(z) reconstruction suggests that the cosmic acceleration could already have peaked and be presently slowing down, what would imply that the recent accelerated expansion of the Universe is a transient phenomenon. It is also shown that to describe a transient acceleration the luminous distance needs to be expanded at least to fourth order. The present cosmographic results depend neither on the validity of general relativity nor on the matter-energy contents of the Universe. (author)

Terrestrial planet formation.

Science.gov (United States)

Righter, K; O'Brien, D P

2011-11-29

Advances in our understanding of terrestrial planet formation have come from a multidisciplinary approach. Studies of the ages and compositions of primitive meteorites with compositions similar to the Sun have helped to constrain the nature of the building blocks of planets. This information helps to guide numerical models for the three stages of planet formation from dust to planetesimals (~10(6) y), followed by planetesimals to embryos (lunar to Mars-sized objects; few 10(6) y), and finally embryos to planets (10(7)-10(8) y). Defining the role of turbulence in the early nebula is a key to understanding the growth of solids larger than meter size. The initiation of runaway growth of embryos from planetesimals ultimately leads to the growth of large terrestrial planets via large impacts. Dynamical models can produce inner Solar System configurations that closely resemble our Solar System, especially when the orbital effects of large planets (Jupiter and Saturn) and damping mechanisms, such as gas drag, are included. Experimental studies of terrestrial planet interiors provide additional constraints on the conditions of differentiation and, therefore, origin. A more complete understanding of terrestrial planet formation might be possible via a combination of chemical and physical modeling, as well as obtaining samples and new geophysical data from other planets (Venus, Mars, or Mercury) and asteroids.

Ultrahigh-energy cosmic rays: facts, myths and legends

International Nuclear Information System (INIS)

Anchordoqui, L.A.

2011-01-01

This is a written version of a series of lectures aimed at graduate students in astrophysics and theoretical/experimental particle physics. In the first part, we explain the important progress made in recent years towards understanding the experimental data on cosmic rays with energies > or approx. 10 8 GeV. We begin with a brief survey of the available data, including a description of the energy spectrum, mass composition and arrival directions. At this point we also give a short overview of experimental techniques. After that, we introduce the fundamentals of acceleration and propagation in order to discuss the conjectured nearby cosmic-ray sources, and emphasize some of the prospects for a new (multiparticle) astronomy. Next, we survey the state of the art regarding the ultrahigh-energy cosmic neutrinos that should be produced in association with the observed cosmic rays. In the second part, we summarize the phenomenology of cosmic-ray air showers. We explain the hadronic interaction models used to extrapolate results from collider data to ultrahigh energies, and describe the prospects for insights into forward physics at the Large Hadron Collider. We also explain the main electromagnetic processes that govern the longitudinal shower evolution. Armed with these two principal shower ingredients and motivation from the underlying physics, we describe the different methods proposed to distinguish primary species. In the last part, we outline how ultrahigh-energy cosmic-ray interactions can be used to probe new physics beyond the electroweak scale. (author)

Cosmic neutrinos as a probe of TeV-scale physics

Energy Technology Data Exchange (ETDEWEB)

Ahlers, M.

2007-02-15

Ultra-high energy cosmic neutrinos are versatile probes of astrophysics, astronomy, and particle physics. They represent the messengers of hadronic processes in cosmic accelerators and survive the propagation through the interstellar medium practically unscathed. We investigate the neutrino fluxes associated with optically thin proton sources which provide a diagnostic of the transition between galactic and extragalactic cosmic rays. The center of mass energies in collisions of these cosmic neutrinos with atomic nuclei in the atmosphere or the Earth's interior easily exceed those so far reached in man-made accelerators. We discuss the prospects of observing supersymmetric neutrino interactions with Cherenkov telescopes and speculate about a neutrino component in extremely high energy cosmic rays from exotic interactions in the atmosphere. (orig.)

Consistency relation for cosmic magnetic fields

DEFF Research Database (Denmark)

Jain, R. K.; Sloth, M. S.

2012-01-01

If cosmic magnetic fields are indeed produced during inflation, they are likely to be correlated with the scalar metric perturbations that are responsible for the cosmic microwave background anisotropies and large scale structure. Within an archetypical model of inflationary magnetogenesis, we show...... that there exists a new simple consistency relation for the non-Gaussian cross correlation function of the scalar metric perturbation with two powers of the magnetic field in the squeezed limit where the momentum of the metric perturbation vanishes. We emphasize that such a consistency relation turns out...... to be extremely useful to test some recent calculations in the literature. Apart from primordial non-Gaussianity induced by the curvature perturbations, such a cross correlation might provide a new observational probe of inflation and can in principle reveal the primordial nature of cosmic magnetic fields. DOI...

Manipulating lightcone fluctuations in an analogue cosmic string

Directory of Open Access Journals (Sweden)

Jiawei Hu

2018-02-01

Full Text Available We study the flight time fluctuations in an anisotropic medium inspired by a cosmic string with an effective fluctuating refractive index caused by fluctuating vacuum electric fields, which are analogous to the lightcone fluctuations due to fluctuating spacetime metric when gravity is quantized. The medium can be realized as a metamaterial that mimics a cosmic string in the sense of transformation optics. For a probe light close to the analogue string, the flight time variance is ν times that in a normal homogeneous and isotropic medium, where ν is a parameter characterizing the deficit angle of the spacetime of a cosmic string. The parameter ν, which is always greater than unity for a real cosmic string, is determined by the dielectric properties of the metamaterial for an analogue string. Therefore, the flight time fluctuations of a probe light can be manipulated by changing the electric permittivity and magnetic permeability of the analogue medium. We argue that it seems possible to fabricate a metamaterial that mimics a cosmic string with a large ν in laboratory so that a currently observable flight time variance might be achieved.

Manipulating lightcone fluctuations in an analogue cosmic string

Science.gov (United States)

Hu, Jiawei; Yu, Hongwei

2018-02-01

We study the flight time fluctuations in an anisotropic medium inspired by a cosmic string with an effective fluctuating refractive index caused by fluctuating vacuum electric fields, which are analogous to the lightcone fluctuations due to fluctuating spacetime metric when gravity is quantized. The medium can be realized as a metamaterial that mimics a cosmic string in the sense of transformation optics. For a probe light close to the analogue string, the flight time variance is ν times that in a normal homogeneous and isotropic medium, where ν is a parameter characterizing the deficit angle of the spacetime of a cosmic string. The parameter ν, which is always greater than unity for a real cosmic string, is determined by the dielectric properties of the metamaterial for an analogue string. Therefore, the flight time fluctuations of a probe light can be manipulated by changing the electric permittivity and magnetic permeability of the analogue medium. We argue that it seems possible to fabricate a metamaterial that mimics a cosmic string with a large ν in laboratory so that a currently observable flight time variance might be achieved.

Scientific results from the cosmic background explorer (COBE)

International Nuclear Information System (INIS)

Bennett, C.L.; Boggess, N.W.; Cheng, E.S.; Hauser, M.G.; Kelsall, T.; Mather, J.C.; Moseley, S.H. Jr.; Shafer, R.A.; Silverberg, R.F.; Murdock, T.L.; Smoot, G.F.; Weiss, R.; Wright, E.L.

1993-01-01

The National Aeronautics and Space Administration (NASA) has flown the COBE satellite to observe the Big Bang and the subsequent formation of galaxies and large-scale structure. Data from the Far-Infrared Absolute Spectrophotometer (FIRAS) show that the spectrum of the cosmic microwave background is that of a black body of temperature T = 2.73 ± 0.06 K, with no deviation from a black-body spectrum greater than 0.25% of the peak brightness. The data from the Differential Microwave Radiometers (DMR) show statistically significant cosmic microwave background anisotropy, consistent with a scale-invariant primordial density fluctuation spectrum. Measurements from the Diffuse Infrared Background Experiment (DIRBE) provide new conservation upper limits to the cosmic infrared background. Extensive modeling of solar system and galactic infrared foregrounds is required for further improvement in the cosmic infrared background limits. 104 refs., 1 tab

Cosmic Ray-Air Shower Measurement from Space

Science.gov (United States)

Takahashi, Yoshiyuki

1997-01-01

A feasibility study has been initiated to observe from space the highest energy cosmic rays above 1021 eV. A satellite observatory concept, the Maximum-energy Auger (Air)-Shower Satellite (MASS), is recently renamed as the Orbital Wide-angle Collector (OWL) by taking its unique feature of using a very wide field-of-view (FOV) optics. A huge array of imaging devices (about 10(exp 6) pixels) is required to detect and record fluorescent light profiles of cosmic ray cascades in the atmosphere. The FOV of MASS could extend to as large as about 60 in. diameter, which views (500 - 1000 km) of earth's surface and more than 300 - 1000 cosmic ray events per year could be observed above 1020 eV. From far above the atmosphere, the MASS/OWL satellite should be capable of observing events at all angles including near horizontal tracks, and would have considerable aperture for high energy photon and neutrino observation. With a large aperture and the spatial and temporal resolution, MASS could determine the energy spectrum, the mass composition, and arrival anisotropy of cosmic rays from 1020 eV to 1022 eV; a region hitherto not explored by ground-based detectors such as the Fly's Eye and air-shower arrays. MASS/OWL's ability to identify cosmic neutrinos and gamma rays may help providing evidence for the theory which attributes the above cut-off cosmic ray flux to the decay of topological defects. Very wide FOV optics system of MASS/OWL with a large array of imaging devices is applicable to observe other atmospheric phenomena including upper atmospheric lightning. The wide FOV MASS optics being developed can also improve ground-based gamma-ray observatories by allowing simultaneous observation of many gamma ray sources located at different constellations.

The Need for Direct High-Energy Cosmic-Ray Measurements

Science.gov (United States)

Jones, Frank C.; Streitmatter, Robert

2004-01-01

Measuring the chemical composition of the cosmic rays in the energy region of greater than or equal to 10(exp 12)eV would be highly useful in settling several nagging questions concerning the propagation of cosmic rays in the galaxy. In particular an accurate measurement of secondary to primary ratios such as Boron to Carbon would gibe clear evidence as to whether the propagation of cosmic rays is determined by a diffusion coefficient that varies with the particle's energy as E(sup 0.5) or E(sup 0.3). This would go a long ways in helping us to understand the anistropy (or lack thereof) of the highest energy cosmic rays and the power requirements for producing those particles at approximately equal to 10(exp 18) eV which are believed to be highest energy particles produced in the Galaxy. This would be only one of the benefits of a mission such as ACCESS to perform direct particle measurements on very high energy cosmic rays.

Anisotropy of the cosmic background radiation

International Nuclear Information System (INIS)

Silk, J.

1988-01-01

The characteristics of the cosmic microwave background radiation (CBR) are reviewed, focusing on intrinsic anisotropies caused by primordial matter fluctuations. The basic elements of the CBR are outlined and the contributions to anisotropy at different angular scales are discussed. Possible fluctuation spectra that can generate the observed large-scale structure of the universe through gravitational instability and nonlinear evolution are examined and compared with observational searches for cosmic microwave anisotropies. 21 refs

The end of the galactic cosmic ray spectrum

Energy Technology Data Exchange (ETDEWEB)

Stanev, Todor [Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)

2007-03-15

We discuss the region of transition between galactic and extragalactic cosmic rays. The exact shapes and compositions of these two components contains information about important parameters of powerful astrophysical sources and the conditions in extragalactic space as well as for the cosmological evolution of the sources of high energy cosmic rays. Several types of experimental data, including the exact shape of the ultrahigh energy cosmic rays, their chemical composition and their anisotropy, and the fluxes of cosmogenic neutrinos have to be included in the solution of this problem.

Consequences of simulating terrestrial N dynamics for projecting future terrestrial C storage

Science.gov (United States)

Zaehle, S.; Friend, A. D.; Friedlingstein, P.

2009-04-01

We present results of a new land surface model, O-CN, which includes a process-based coupling between the terrestrial cycling of energy, water, carbon, and nitrogen. The model represents the controls of the terrestrial nitrogen (N) cycling on carbon (C) pools and fluxes through photosynthesis, respiration, changes in allocation patterns, as well as soil organic matter decomposition, and explicitly accounts for N leaching and gaseous losses. O-CN has been shown to give realistic results in comparison to observations at a wide range of scales, including in situ flux measurements, productivity databases, and atmospheric CO2 concentration data. Notably, O-CN simulates realistic responses of net primary productivity, foliage area, and foliage N content to elevated atmospheric [CO2] as evidenced at free air carbon dioxide enrichment (FACE) sites (Duke, Oak Ridge). We re-examine earlier model-based assessments of the terrestrial C sequestration potential using a global transient O-CN simulation driven by increases in atmospheric [CO2], N deposition and climatic changes over the 21st century. We find that accounting for terrestrial N cycling about halves the potential to store C in response to increases in atmospheric CO2 concentrations; mainly due to a reduction of the net C uptake in temperate and boreal forests. Nitrogen deposition partially alleviates the effect of N limitation, but is by far not sufficient to compensate for the effect completely. These findings underline the importance of an accurate representation of nutrient limitations in future projections of the terrestrial net CO2 exchanges and therefore land-climate feedback studies.

Measurement of cosmic-ray reconstruction efficiencies in the MicroBooNE LArTPC using a small external cosmic-ray counter

Energy Technology Data Exchange (ETDEWEB)

Acciarri, R.; et al.

2017-07-31

The MicroBooNE detector is a liquid argon time projection chamber at Fermilab designed to study short-baseline neutrino oscillations and neutrino-argon interaction cross-section. Due to its location near the surface, a good understanding of cosmic muons as a source of backgrounds is of fundamental importance for the experiment. We present a method of using an external 0.5 m (L) x 0.5 m (W) muon counter stack, installed above the main detector, to determine the cosmic-ray reconstruction efficiency in MicroBooNE. Data are acquired with this external muon counter stack placed in three different positions, corresponding to cosmic rays intersecting different parts of the detector. The data reconstruction efficiency of tracks in the detector is found to be $\\epsilon_{\\mathrm{data}}=(97.1\\pm0.1~(\\mathrm{stat}) \\pm 1.4~(\\mathrm{sys}))\\%$, in good agreement with the Monte Carlo reconstruction efficiency $\\epsilon_{\\mathrm{MC}} = (97.4\\pm0.1)\\%$. This analysis represents a small-scale demonstration of the method that can be used with future data coming from a recently installed cosmic-ray tagger system, which will be able to tag $\\approx80\\%$ of the cosmic rays passing through the MicroBooNE detector.

Does electromagnetic radiation accelerate galactic cosmic rays

Science.gov (United States)

Eichler, D.

1977-01-01

The 'reactor' theories of Tsytovich and collaborators (1973) of cosmic-ray acceleration by electromagnetic radiation are examined in the context of galactic cosmic rays. It is shown that any isotropic synchrotron or Compton reactors with reasonable astrophysical parameters can yield particles with a maximum relativistic factor of only about 10,000. If they are to produce particles with higher relativistic factors, the losses due to inverse Compton scattering of the electromagnetic radiation in them outweigh the acceleration, and this violates the assumptions of the theory. This is a critical restriction in the context of galactic cosmic rays, which have a power-law spectrum extending up to a relativistic factor of 1 million.

Cosmic rays and radiations from the cosmos

International Nuclear Information System (INIS)

Parizot, E.

2005-12-01

This document gathers a lot of recent information concerning cosmic radiations, it is divided into 4 parts. Part I: energy, mass and angular spectra of cosmic rays. Part II: general phenomenology of cosmic rays, this part deals with the standard model, the maximal energy of protons inside supernova remnants, nucleosynthesis of light elements, and super-bubbles. Part III: radiations from the cosmos, this part deals with high energy gamma rays, non-thermal radiation of super-bubbles, positron transport, and the Compton trail of gamma-ray bursts. Part IV: the Pierre Auger observatory (OPA), this part deals with the detection of gamma ray bursts at OPA, the measurement of anisotropy, and top-down models. (A.C.)

The Hubble Web: The Dark Matter Problem and Cosmic Strings

International Nuclear Information System (INIS)

Alexander, Stephon

2009-01-01

I propose a reinterpretation of cosmic dark matter in which a rigid network of cosmic strings formed at the end of inflation. The cosmic strings fulfill three functions: At recombination they provide an accretion mechanism for virializing baryonic and warm dark matter into disks. These cosmic strings survive as configurations which thread spiral and elliptical galaxies leading to the observed flatness of rotation curves and the Tully-Fisher relation. We find a relationship between the rotational velocity of the galaxy and the string tension and discuss the testability of this model.

The Hubble Web: The Dark Matter Problem and Cosmic Strings

Science.gov (United States)

Alexander, Stephon

2009-07-01

I propose a reinterpretation of cosmic dark matter in which a rigid network of cosmic strings formed at the end of inflation. The cosmic strings fulfill three functions: At recombination they provide an accretion mechanism for virializing baryonic and warm dark matter into disks. These cosmic strings survive as configurations which thread spiral and elliptical galaxies leading to the observed flatness of rotation curves and the Tully-Fisher relation. We find a relationship between the rotational velocity of the galaxy and the string tension and discuss the testability of this model.

Development of cosmic-ray radiography with nuclear emulsion and its applications

International Nuclear Information System (INIS)

Morishima, Kunihiro

2017-01-01

We are developing cosmic-ray radiography with nuclear emulsion. Cosmic-ray radiography is non-destructive inspection technology to take image of inner structure of gigantic objects (nuclear reactor, pyramids, volcanoes and so on). We conducted cosmic-ray radiography of Fukushima Daiichi Nuclear Power Plant from 2014 to 2015 and are conducting cosmic-ray radiography of Pyramids at Egypt from 2015. In this paper, technical details and latest results are presented. (author)

Cosmic-ray neutron simulations and measurements in Taiwan

International Nuclear Information System (INIS)

Chen, Wei-Lin; Jiang, Shiang-Huei; Sheu, Rong-Jiun

2014-01-01

This study used simulations of galactic cosmic ray in the atmosphere to investigate the neutron background environment in Taiwan, emphasising its altitude dependence and spectrum variation near interfaces. The calculated results were analysed and compared with two measurements. The first measurement was a mobile neutron survey from sea level up to 3275 m in altitude conducted using a car-mounted high-sensitivity neutron detector. The second was a previous measured result focusing on the changes in neutron spectra near air/ground and air/water interfaces. The attenuation length of cosmic-ray neutrons in the lower atmosphere was estimated to be 163 g cm -2 in Taiwan. Cosmic-ray neutron spectra vary with altitude and especially near interfaces. The determined spectra near the air/ground and air/water interfaces agree well with measurements for neutrons below 10 MeV. However, the high-energy portion of spectra was observed to be much higher than our previous estimation. Because high-energy neutrons contribute substantially to a dose evaluation, revising the annual sea-level effective dose from cosmic-ray neutrons at ground level in Taiwan to 35 μSv, which corresponds to a neutron flux of 5.30 x 10 -3 n cm -2 s -1 , was suggested. The cosmic-ray neutron background in Taiwan was studied using the FLUKA simulations and field measurements. A new measurement was performed using a car-mounted high-efficiency neutron detector, re-coding real-time neutron counting rates from sea level up to 3275 m. The attenuation of cosmic-ray neutrons in the lower atmosphere exhibited an effective attenuation length of 163 g cm -2 . The calculated neutron counting rates over predicted the measurements by ∼32 %, which leaded to a correction factor for the FLUKA-calculated cosmic-ray neutrons in the lower atmosphere in Taiwan. In addition, a previous measurement regarding neutron spectrum variation near the air/ground and air/water interfaces was re-evaluated. The results showed that the

Balloon test project: Cosmic Ray Antimatter Calorimeter (CRAC)

Science.gov (United States)

Christy, J. C.; Dhenain, G.; Goret, P.; Jorand, J.; Masse, P.; Mestreau, P.; Petrou, N.; Robin, A.

1984-01-01

Cosmic ray observations from balloon flights are discussed. The cosmic ray antimatter calorimeter (CRAC) experiment attempts to measure the flux of antimatter in the 200-600 Mev/m energy range and the isotopes of light elements between 600 and 1,000 Mev/m.

Sulphur mountain: Cosmic ray intensity records

International Nuclear Information System (INIS)

Venkatesan, D.; Mathews, T.

1985-01-01

This book deals with the comic ray intensity registrations at the Sulphur Mountain Cosmic Ray Laboratory. The time series of intensity form a valuable data-set, for studying cosmic ray intensity variations and their dependence on solar activity. The IGY neutron monitor started operating from July 1, 1957 and continued through 1963. Daily mean values are tabulated for the period and these are also represented in plots. This monitor was set up by the National Research Council of Canada

Exceptional Colloquium: The Rise, Fall, and Rebirth of Cosmic Strings

CERN Multimedia

CERN. Geneva; Treille, D; Alvarez-Gaumé, Luís

2005-01-01

In the 1980s many people were excited by the concept that cosmic strings, as relics of the Grand Unified Era, could be responsible for the formation of cosmic structure. In the 1990s the cosmic string concept steadily lost ground to the Inflationary model both as a result of the difficulty of calculations and more definitively through observations of the CMB. About the time many expected the new WMAP data to deliver the coup de grace, the concepts of cosmic strings as major physical phenomena (not so important in structure formation) has begun a renaissance. This new interest is motivated by one of the original ideas that topological defects are inevitable in symmetry breaking by the Kibble (1976) mechanism and the introduction of new ideas such as brane-cosmology/inflation and the realization that cosmic strings may be the only acceptable such defect. We find ourselves back in the business of trying to detect or limit and understand cosmic strings once again for the insight and constraints they put on partic...

Exceptional Colloquium: The Rise, Fall, and Rebirth of Cosmic Strings

CERN Multimedia

CERN. Geneva

2005-01-01

In the 1980s many people were excited by the concept that cosmic strings, as relics of the Grand Unified Era, could be responsible for the formation of cosmic structure. In the 1990s the cosmic string concept steadily lost ground to the Inflationary model both as a result of the difficulty of calculations and more definitively through observations of the CMB. About the time many expected the new WMAP data to deliver the coup de grace, the concepts of cosmic strings as major physical phenomena (not so important in structure formation) has begun a renaissance. This new interest is motivated by one of the original ideas that topological defects are inevitable in symmetry breaking by the Kibble (1976) mechanism and the introduction of new ideas such as brane-cosmology/inflation and the realization that cosmic strings may be the only acceptable such defect. We find ourselves back in the business of trying to detect or limit and understand cosmic strings once again for the insight and constraints they put on p...

Cosmic Ray Studies with IceCube

Science.gov (United States)

Gonzalez, Javier

In this contribution we will give an overview of the cosmic ray studies conducted within the IceCube collaboration. The IceCube detector in the geographical south pole can be used to measure various characteristics of the extensive air showers induced by high energy cosmic rays. With IceTop, the surface component of the detector, we detect the electromagnetic and muon components of the air showers, while with the deep detector we detect the high energy muons. We have measured the energy spectrum of cosmic ray primaries in the range between 1.58PeV and 1.26 EeV. A combined analysis of the high energy muon bundles in the ice and the air shower footprint in IceTop provides a measure of primary composition. We will also discuss how the sensitivity to low energy muons in the air showers has the potential to produce additional measures of primary composition.

Preliminary test Results for a 25K Sorption Cryocooler Designed for the UCSB Long Duration Balloon Cosmic Microwave Background Radiation Experiment

Science.gov (United States)

Wade, L. A.; Levy, A. R.

1996-01-01

A continuous operation, vibration-free, long-life 25K sorption cryocooler has been built and is now in final integration and performance testing. This cooler wil be flown on the University of California at Santa Barbara (UCSB) Long Duration Balloon (LDB) Cosmic Microwave Background Radiation Experiment.

Cosmic chirality both true and false.

Science.gov (United States)

Barron, Laurence D

2012-12-01

The discrete symmetries of parity P, time reversal T, and charge conjugation C may be used to characterize the properties of chiral systems. It is well known that parity violation infiltrates into ordinary matter via an interaction between the nucleons and electrons, mediated by the Z(0) particle, that lifts the degeneracy of the mirror-image enantiomers of a chiral molecule. Being odd under P but even under T, this P-violating interaction exhibits true chirality and so may induce absolute enantioselection under all circumstances. It has been suggested that CP violation may also infiltrate into ordinary matter via a P-odd, T-odd interaction mediated by the (as yet undetected) axion. This CP-violating interaction exhibits false chirality and so may induce absolute enantioselection in processes far from equilibrium. Both true and false cosmic chirality should be considered together as possible sources of homochirality in the molecules of life. Copyright © 2012 Wiley Periodicals, Inc.

COSMIC-RAY POSITRONS FROM MILLISECOND PULSARS

Energy Technology Data Exchange (ETDEWEB)

Venter, C.; Kopp, A.; Büsching, I. [Centre for Space Research, North-West University, Potchefstroom Campus, Private Bag X6001, Potchefstroom 2520 (South Africa); Harding, A. K. [Astrophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Gonthier, P. L. [Hope College, Department of Physics, Holland, MI (United States)

2015-07-10

Observations by the Fermi Large Area Telescope of γ-ray millisecond pulsar (MSP) light curves imply copious pair production in their magnetospheres, and not exclusively in those of younger pulsars. Such pair cascades may be a primary source of Galactic electrons and positrons, contributing to the observed enhancement in positron flux above ∼10 GeV. Fermi has also uncovered many new MSPs, impacting Galactic stellar population models. We investigate the contribution of Galactic MSPs to the flux of terrestrial cosmic-ray electrons and positrons. Our population synthesis code predicts the source properties of present-day MSPs. We simulate their pair spectra invoking an offset-dipole magnetic field. We also consider positrons and electrons that have been further accelerated to energies of several TeV by strong intrabinary shocks in black widow (BW) and redback (RB) systems. Since MSPs are not surrounded by pulsar wind nebulae or supernova shells, we assume that the pairs freely escape and undergo losses only in the intergalactic medium. We compute the transported pair spectra at Earth, following their diffusion and energy loss through the Galaxy. The predicted particle flux increases for non-zero offsets of the magnetic polar caps. Pair cascades from the magnetospheres of MSPs are only modest contributors around a few tens of GeV to the lepton fluxes measured by the Alpha Magnetic Spectrometer, PAMELA, and Fermi, after which this component cuts off. The contribution by BWs and RBs may, however, reach levels of a few tens of percent at tens of TeV, depending on model parameters.

Aquatic and Terrestrial Environment 2004

DEFF Research Database (Denmark)

Andersen, J. M.; Boutrup, S.; Bijl, L. van der

This report presents the 2004 results of the Danish National Monitoring and Assess-ment Programme for the Aquatic and Terrestrial Environments (NOVANA). 2004 was the first year in which terrestrial nature was included in the monitoring pro-gramme. The report reviews the state of the groundwater......, watercourses, lakes and marine waters and the pressures upon them and reviews the monitoring of terrestrial natural habitats and selected plants and animals. The report is based on the annual reports prepared for each subprogramme by the Topic Centres. The latter reports are mainly based on data collected...

The bispectrum of matter perturbations from cosmic strings

Energy Technology Data Exchange (ETDEWEB)

Regan, Donough; Hindmarsh, Mark, E-mail: d.regan@sussex.ac.uk, E-mail: m.b.hindmarsh@sussex.ac.uk [Astronomy Centre, University of Sussex, Falmer, Brighton, BN1 9QH (United Kingdom)

2015-03-01

We present the first calculation of the bispectrum of the matter perturbations induced by cosmic strings. The calculation is performed in two different ways: the first uses the unequal time correlators (UETCs) of the string network - computed using a Gaussian model previously employed for cosmic string power spectra. The second approach uses the wake model, where string density perturbations are concentrated in sheet-like structures whose surface density grows with time. The qualitative and quantitative agreement of the two gives confidence to the results. An essential ingredient in the UETC approach is the inclusion of compensation factors in the integration with the Green's function of the matter and radiation fluids, and we show that these compensation factors must be included in the wake model also. We also present a comparison of the UETCs computed in the Gaussian model, and those computed in the unconnected segment model (USM) used by the standard cosmic string perturbation package CMBACT. We compare numerical estimates for the bispectrum of cosmic strings to those produced by perturbations from an inflationary era, and discover that, despite the intrinsically non-Gaussian nature of string-induced perturbations, the matter bispectrum is unlikely to produce competitive constraints on a population of cosmic strings.

The Energetic Trans-Iron Cosmic-ray Experiment (ENTICE)

Science.gov (United States)

Binns, W. R.; Adams. J. H.; Barghouty, A. F.; Christian, E. R.; Cummings, A. C.; Hams, T.; Israel, M. H.; Labrador, A. W.; Leske, R. A.; Link, J. T.;

The Probe of Inflation and Cosmic Origins

Science.gov (United States)

Hanany, Shaul; Inflation Probe Mission Study Team

2018-01-01

The Probe of Inflation and Cosmic Origins will map the polarization of the cosmic microwave background over the entire sky with unprecedented sensitivity. It will search for gravity wave signals from the inflationary epoch, thus probing quantum gravity and constraining the energy scale of inflation; it will test the standard model of particle physics by measuring the number of light particles in the Universe and the mass of the neutrino; it will elucidate the nature of dark matter and search for new forms of matter in the early Universe; it will constrain star formation history over cosmic time; and it will determine the mechanisms of structure formation from galaxy cluster to stellar scales. I will review the status of design of this probe-scale mission.