Abundance Of Light Nuclei In The Primary Cosmic Radiation
Below is result for Abundance Of Light Nuclei In The Primary Cosmic Radiation in PDF format. You can download or read online all document for free, but please respect copyrighted ebooks. This site does not host PDF files, all document are the property of their respective owners.
THE MULTIPLY-CHARGED PRIMARY COSMIC RADIATION AT SOLAR
THE MULTIPLY-CHARGED PRIMARY COSMIC RADIATION AT SOLAR MINIMUM, 1965 ABSTRACT The primary cosmic ray charge and energy spectra have been obtained for Helium through Neon during the recent period when solar modulation effects were at a minimum. These spectra repre- sent a synthesis of preliminary experimental results from cosmic
The dominance of secondary nuclei in the cosmic radiation and
The dominance of secondary nuclei in the cosmic radiation and the modulation of the nuclear species at the injection of the galactic accelerator Antonio Codino University of Perugia and INFN E-mail: [email protected] The cosmic ray abundances are compared to those of the quiescent matter referred to as galactic or solar abundances.
124 THE ABUNDANCES OF ISOTOPES IN THE COSMIC RADIATION
COSMIC RAY CLOCKS AND SECONDARY NUCLEI It is generally accepted that typical cosmic ray nuclei with energies below a few GeV/nuclcon have traversed an average of 6 to 9 g/cm 2 of material during their lifetime, as evidenced by the abundances of secondary nuclei such as Li, Be, and B in cosmic rays.
Light Nuclei and Isotope Abundance in Cosmic Rays Measured by
antimatter in the cosmic radiation, will investigate phenomena connected with Solar and Earth physics and will measure the light nuclear component of Galactic cosmic rays. In particular, measurements of cosmic rays of primary origin such as Carbon, Nitrogen and Oxygen or their fragments such as Lithium, Beryllium and Boron may provide
p, He, and C to Fe cosmic-ray primary ﬂuxes in diffusion models
ated by interactions of the primary species in the ISM and radiation ﬁelds of the Galaxy) including light nuclei, anti pro-tons, positrons, radioactive isotopes and also gamma rays. The transport parameters are usually determined by ﬁtting data on secondary-to-primary ratios of nuclei, as for example the B/C (boron-to-carbon) ratio.
I Cosmic Rays - UMD
This primary cosmic radiation produces secondary particles in collisions with atomic nuclei in the upper reaches of the atmosphere. It is this secondary cosmic radiation which penetrates the thick blanket of air and reaches us at sea-level. The primary cosmic radiation is isotropic, that is, its intensity is the same for all possible directions.
86 89 percent of the abundance. Interaction cross sections for 4He-ill collisions have long been of interest (refs. 1-3) in the understanding of the chemical composition of the primary cosmic radiation because their interaction is the chief mechanism for 2H and 3He productions which are absent from the primary sources.
The rule governing the abundances of cosmic rays at the
study because they are secondary nuclei of the cosmic radiation copiously produced by spallation reactions in the interstellar medium. These nuclei leave an indelible mark on the function A cr/ A g consisting in asystematic superabundance of odd nuclei relative tothe adjacent even nuclei (Z=6, 8, 10, 12, 14, 16, 18 and 20)
ENERGY SPECTRA OF PRIMARY AND SECONDARY COSMIC-RAY NUCLEI
region. The relative abundances of the primary nuclei, such as carbon, oxygen, and iron, above ∼10 GeV amu−1 are independent of energy, while the boron abundance, i.e., the B/C abundance ratio, decreases with energy as expected. However, there is an indication that the previously reported E−0.6 dependence of the B/C ratio does not
THE PRIMARY COSMIC RADIATION
the cosmic radiation have just begun, and Relative Abundances early results for the helium isotopes are of the Elements (Z Ž. 3) in the Primary discussed in the second half of this lecture. Cosmic Radiation* Our knowledge of primaries other than Relative to All Relative to Carbon nuclei is rudimentary.
Light nuclei identification capab ility of the PAMELA apparatus
cosmic-ray transport within the Galaxy. The ratios of the spallogenic nuclei (B, Be, and Li) to mostly primary nuclei such as C are particularly impor-tant in constraining propagation models since these ratios are sensitive to the amount of material traversed by GCRs from the source to detection at Earth. In addition, abundance ratios tend to be
Energy spectra of cosmic-ray nuclei at high energies
primary nuclei with the ISM. The amount of material traversed by cosmic rays between injec-tion and observation can be derived from the measured ratio of secondary-to-primary nuclei, such as the boron-to-carbon ratio (B/C) or the ratio of sub-iron elements to iron. Likewise,
Simulation of radiation field inside interplanetary spacecraft
12 m) of a spacecraft generated by isotropic Galactic Cosmic Radiation (GCR) in deep interplanetary space is carried out for minimum and maximum solar activity using the FLUKA code. Protons, alpha-particles, deuterons, 3He, and nuclei with Z > 2 are considered as primary GCR irradiating the spacecraft isotropically.
(Anti-)Nuclei production at the LHC with ALICE
equal abundance of matter and anti-matter in the central rapidity region A large number of particles is produced: dN ch /dη ≈ 2000 (central Pb-Pb collisions) Phys. Rev. Lett.109, 252301 Even in heavy ion collisions, light (anti-)nuclei are rarely produced: (Anti-)nuclei up to A = 4 are within reach
Capability of the PAMELA instrument to identify light-nuclei
propagation of Galactic cosmic rays it is fundamental to have more precise and extended data on the secondary/primary abundance ratios (like the ratio B/C) and on the fluxes of primary particles: in this field PAMELA can represent a big step ahead. Object of this paper is the presentation of the light-charge
Big Bang Nucleosynthesis and the Cosmological Lithium Problem
abundances of light nuclei and the observed abundances, namely the disagreement between the BBN predicted abundance of 7Li and the measured abundance. The theory is o by about a factor of ˘3 to 4 (meaning there is about 3 to 4 times less Lithium than expected) which de nes the cosmological lithium problem.
The cosmic radiation*
diameter, give - with light loads of about 20 kg - level flights at altitudes of the order of 95,000 ft. It is anticipated that a similar ballon 50 m in diametero should reach about120,000 ft. By observations at great altitudes we now know that the primary cosmic radiation is made up of atomic nuclei moving at speeds closely approaching
Thomas K. Gaisser & Todor Stanev
understanding the origin of the cosmic radiation. 1 Introduction The cosmic-ray spectrum falls steeply, decreasing by approximately a factor of 50 per decade increase in energy when plotted as Eφ(E) = dN/dln(E). In the lowest energy region the ﬂux is high enough so that the elemental composition of the primary cosmic-ray nuclei can be
Deﬁnitive measurements of secondary production of cosmic-ray
dence of the galactic propagation of cosmic rays is necessary to understand their energy spectra and acceleration at the sources. A key observation is the measurement of the relative abundances of secondary nuclei, such as the light nuclei below carbon and the sub-iron nuclei, and of the partially secondary odd-Z nuclei.
STATISTICAL CHARACTERISTICS OF ELEMENTAL ABUNDANCE RATIOS
intensities and energy spectra of light secondary nuclei are produced exclusively from the nuclear interactions of primary cosmic rays with the interstellar medium. As a result, they are naturally utilized to study and constrain parameters in propagation models for GCRs, providing detailed information
THE BORON-TO-CARBON ABUNDANCE RATIO AND GALACTIC PROPAGATION
spectra and the absolute intensities of the cosmic-ray nuclei from boron (Z = 5) to iron (Z = 26) up to very high energies. In particular, the second ﬂight has led to results on the energy spectrum of the secondary boron nuclei, and on the boron abundance relative to that of the heavier primary parent nuclei, commonly quantiﬁed as the B/C
and T is the ambient temperature of the radiation eld, and istands for the speci c species. We would like to nd a relation between the ionization fraction xand cosmic time t, or redshift z; we expect xto decrease with t. Since Tis a monotonically increasing function of z, we could start by nding a relation between xand T. Consider the following
The cosmic radiation* - Nobel Prize
diameter, give - with light loads of about 20 kg - level flights at altitudes of the order of 95,000 ft. It is anticipated that a similar balloon 50 m in diameter should reach about 120,000 ft. By observations at great altitudes we now know that the primary cosmic radiation is made up of atomic nuclei moving at speeds closely approaching
On the Origin of Cosmic Radiation - Wiley Online Library
several times. The primary radiation was at first believed to be a y radiation, later a B radiation, until it was proved to consist merely of protons. Recently even heavy nuclei have been found in the primary radiation. Even the views concerning the isotropy and constancy of cosmic radiation have been revised from time to time.
THE LOW ENERGY SPECTRUM OF COSMIC RAYSAS AN IMDK OF SOURCE
cosmic radiation with very large abundance when compared to their universal abundance. As these nuclei are easily destroyed in nuclear interactions at stellar temperatures, it is reasonable to assume that they are probably not present in the source regions, but are produced in nuclear collisions of heavier
Heavy versus Light Nuclei in Primary Cosmic Rays using
Investigation of the Relative Abundance of Heavy versus Light Nuclei in Primary Cosmic Rays using Underground Muon Bundles by Nakamuthu Sundaralingam, Ph.D. Dissertation Director: Prof. W. A. Mann We study multiple muon events (muon bundles) recorded underground at a depth of 2090 rowe. To penetrate to this depth, the muons must have energies
determinations made in many balloon of relative cosmic-ray abundance to mic radiation cont fiights in Texas, at a geomagnetic lati- relative general abundance for each fraction of these tude of about 41'N (10). component. The most startling ratio is confiicting res Table 1, column 3, gives the rela- that for the light elements-lithium, ing
Q I. ,:ENGINEERING PAPER
neutrons caused by primary cosmic ray particles interacting with planet-ary atmospheres). Protons constitute the greatest radiation hazard in space, although electrons are the primary concern in the outer regions of the magneto-sphere (i.e., outer Van Allen zone). For purposes of simplicity, we will
COMPOSITION OF PRIMARY COSMIC-RAY NUCLEI AT HIGH ENERGIES
COMPOSITION OF PRIMARY COSMIC-RAY NUCLEI AT HIGH ENERGIES M. Ave, P. J. Boyle,1 F. Gahbauer,2 C. Ho¨ppner,3 J. R. Ho¨randel,4 M. Ichimura,5 D. Mu¨ller, and A. Romero-Wolf6 Enrico Fermi Institute, University of Chicago, 933 East 56th Street, Chicago, IL 60637; [email protected] Received 2007 September 14; accepted 2008 January 3 ABSTRACT
Physics and AstroparticlePhysics A. A. 2020-2021
Primary Cosmic Rays (C.R.) intensity, energy spectrum and composition. A power law can describe the C.R. energy spectrum. Energy density in C.R., in the Microwave Cosmic Background Radiation (MCBR), in the Galactic Magnetic field. C.R. composition: relative abundance of elements in the Earth (Solar System) and on the C.R
,M.Ave ,P.Boyle arXiv:1108.4838v1 [astro-ph.HE] 24 Aug 2011
The TRACER cosmic-ray detector, ﬁrst ﬂown on long-duration balloon (LDB) in 2003 for observations of the major primary cosmic-ray nuclei from oxygen (Z = 8) to iron (Z = 26), has been upgraded to also measure the energies of the lighter nuclei, including the secondary species boron (Z = 5). The instrument was used in another LDB ﬂight in
Cosmic Rays and Particle Acceleration
Primary cosmic rays collide with molecules in the atmosphere and yield secondary particles in an air shower I Common products: pions, electrons, positrons, neutrons, kaons, muons, and neutrinos I Particles produce Cherenkov radiation that is detectable
Chapter 8 Cosmic Rays - University of Washington
The abundance of primary CR is essentially diﬀerent from the standard abundance of nuclei in the Universe (Table. 2.1). The diﬀerence is biggest for light nuclei (L = Li, Be, B) which are mainly produced by CR collisions with interstellar matter in the Galaxy. The relative abundance of diﬀerent elements in cosmic rays is shown also in Fig
International Conference OnCosmic Rays
Emulsions-Part III* The Light Nuclei of the Coaaic Radiation N. Durgapraaad 17 5-6. Flux and Energy Spectra of Heavy Primary H-lagoda Huolei Meaaured on Polar Orbiting Sata-K. Fukni llitea 24 8- 6. Study of the Relative Abundance of tha Primary Cosmic Ray Nuclei with Z * 26 0, Alvial J. Riquelmi 52 5- 7. Energy Spectrum of Heavy Nuclei of
3) Natural and Artificial Radioactivity (2)
- Protons (93 %) Cosmic Radiation - Alpha-Particles (6.3 %) - heavier nuclides (0.7 %) - energy of the protons can be up to 1014 MeV - initialisation of nuclear reactions - Main products: Tritium, 7Beryllium, 14Carbon, 22Sodium Primary cosmic radiation Secondary radiation Interaction with nuclei of the air 14C: Formation N n C1 p 1 14 7 0 → 6+
Fabrications and Characterizations of Boron Containing
radiation effects are galactic cosmic rays. Galactic cosmic rays are high-energy particles (up to 1010 GeV) that originate in outer space and primarily consist of protons and alpha particles (90%). More importantly, the other 10% consists of higher atomic number nuclei ranging from Z = 5 to 83.
Composition and energy spectra of cosmic-ray nuclei at high
surement of the abundance ratio of secondary to primary cosmic-ray nuclei at high energies, e.g. boron to carbon. The TRACER instrument was upgraded and ﬂown to accomplish such a measurement. II. UPGRADES AND LDB FLIGHT 2006 For the 2006 ﬂight, an additional acrylic Cerenkov detector at the top of the instrument was included.
GeV - University of Washington
stellar light of 0.3 eV/cm3. The principal components of the (primary) cosmic rays are shown Figure 1. This abundance distribution is approximately independent of energy, at least over the dominant energy range of 10 MeV/nucleon through several GeV/nucleon. By mass about 79% of nucleons in cosmic
Primary Cosmic Rays
Jul 29, 2017 ABUNDANCES DETERMINED FROM COSMIC-RAY RATIOS COMPARED WITH UNIVERSAL ABUNDANCES a Heavy nuclei Light Medium Very Group Hydrogen Helium nuclei nuclei Fe heavy Li, Be, B CNOF Z > 10 23 < Z nuclei < 30 Relative abundance in 100 15.5 0.24 1.20 0.4 0.1 <10-4 cosmic rays Universal abundance 100 7.7 10-6 0.20 0.03 0.003 -10-6 (Suess and Urey)