Heavy nuclei enrichment of the galactic cosmic rays at high energy: astrophysical interpretation

The ‘Galactic’ cosmic rays impinging on the Earth come from afar over tortuous paths, traveling for millions of years. These particles are the only known samples of matter that reach us from regions of space beyond the solar system. Their chemical and isotopic composition and their energy spectra provide clues to the nature of cosmic-ray sources, the properties of interstellar space, and the dynamics of the Galaxy. Various processes in high-energy astrophysics could be illuminated by a more complete understanding of the arriving cosmic rays, including the electrons and gamma rays.En route, some of theprimordialcosmic-ray nuclei have been transformed by collision with interstellar matter, and the composition is substantially modified by these collisions. A dramatic consequence of the transformations is the presence in the arriving ‘beam’ of considerable fluxes of purely secondary elements (Li, Be, B), i.e., species that are, in all probability, essentially absent at the sources. We shall here discuss mainly the composition of the arriving ‘heavy’ nuclei -those heavier than helium - and what they teach us about thesourcecomposition, the galactic confinement of the particles, their path lengths, and their transit times.

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ACTIVE GALACTIC NUCLEI: SOURCES FOR ULTRA HIGH ENERGY COSMIC RAYS

International Journal of Modern Physics D ◽

10.1142/s0218271809015369 ◽

2009 ◽

Vol 18 (10) ◽

pp. 1577-1581 ◽

Cited By ~ 5

Author(s):

P. L. BIERMANN ◽

J. K. BECKER ◽

L. CARAMETE ◽

L. GERGELY ◽

I. C. MARIŞ ◽

...

Keyword(s):

Cosmic Rays ◽

Radio Galaxy ◽

Galactic Nuclei ◽

Cosmic Ray ◽

High Energy ◽

Galactic Cosmic Rays ◽

Ultra High Energy ◽

Heavy Nuclei ◽

High Energy Cosmic Rays ◽

Relativistic Jet

Ultra high energy cosmic ray events presently show a spectrum, which we interpret here as galactic cosmic rays due to a starburst, in the radio galaxy Cen A which is pushed up in energy by the shock of a relativistic jet. The knee feature and the particles with energy immediately higher in galactic cosmic rays then turn into the bulk of ultra high energy cosmic rays. This entails that all ultra high energy cosmic rays are heavy nuclei. This picture is viable if the majority of the observed ultra high energy events come from the radio galaxy Cen A, and are scattered by intergalactic magnetic fields across much of the sky.

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27-day variations of the galactic cosmic rays intensity and anisotropy in solar minima 23/24 and 24/25 by ACE/CRIS, STEREO, SOHO/EPHIN and neutron monitors

10.5194/egusphere-egu21-13185 ◽

2021 ◽

Author(s):

Renata Modzelewska ◽

Agnieszka Gil

Keyword(s):

Cosmic Rays ◽

Large Scale ◽

Solar Rotation ◽

High Energy ◽

Galactic Cosmic Rays ◽

Magnetic Polarity ◽

Analysis Method ◽

Enhanced Diffusion ◽

Diffusion Effects ◽

Solar Wind Parameters

We study the 27-day variations of galactic cosmic rays (GCRs) based on neutron monitor (NM), ACE/CRIS, STEREO and SOHO/EPHIN measurements, in solar minima 23/24 and 24/25 characterized by the opposite polarities of solar magnetic cycle. Now there is an opportunity to re-analyze the polarity dependence of the amplitudes of the recurrent GCR variations in 2007-2009 for negative A < 0 solar magnetic polarity and to compare it with the clear periodic variations related to solar rotation in 2017-2019 for positive A > 0. We use the Fourier analysis method to study the periodicity in the GCR fluxes. Since the GCR recurrence is a consequence of solar rotation, we analyze not only GCR fluxes, but also solar and heliospheric parameters examining the relationships between the 27-day GCR variations and heliospheric, as well as, solar wind parameters. We find that the polarity dependence of the amplitudes of the 27-day variations of the GCR intensity and anisotropy for NMs data is kept for the last two solar minima: 23/24 (2007-2009) and 24/25 (2017-2019) with greater amplitudes in positive A > 0 solar magnetic polarity. ACE/CRIS, SOHO/EPHIN and STEREO measurements are not governed by this principle of greater amplitudes in positive A > 0 polarity. GCR recurrence caused by the solar rotation for low energy (< 1GeV) cosmic rays is more sensitive to the enhanced diffusion effects, resulting in the same level of the 27-day amplitudes for positive and negative polarities. While high energy (> 1GeV) cosmic rays registered by NMs, are more sensitive to the large-scale drift effect leading to the 22-year Hale cycle in the 27-day GCR variation, with the larger amplitudes in the A > 0 polarity than in the A < 0.

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Modelling the influence of high-energy radiation on the atmospheric composition of the hot Jupiter HD 189733b

10.5194/egusphere-egu21-936 ◽

2021 ◽

Author(s):

Patrick Barth ◽

Christiane Helling ◽

Eva E. Stüeken ◽

Vincent Bourrier ◽

Nathan Mayne ◽

...

Keyword(s):

Cosmic Rays ◽

High Energy ◽

Galactic Cosmic Rays ◽

Energetic Particles ◽

Atmospheric Composition ◽

Cloud Formation ◽

Fine Grid ◽

High Energy Radiation ◽

Energy Radiation ◽

Hot Jupiter

Hot Jupiters provide valuable natural laboratories for studying potential contributions of high-energy radiation to prebiotic synthesis in the atmospheres of exoplanets. HD 189733b, a hot Jupiter orbiting a K star, is one of the most studied and best observed exoplanets. We combine XUV observations and 3D climate simulations to model the atmospheric composition and kinetic chemistry with the STAND2019 network. We show how XUV radiation, cosmic rays (CR), and stellar energetic particles (SEP) influence the chemistry of the atmosphere. We explore the effect that the change in the XUV radiation has over time, and we identify key atmospheric signatures of an XUV, CR, and SEP influx. 3D simulations of HD 189733b's atmosphere with the 3D Met Office Unified Model provide a fine grid of pressure-temperature profiles, consistently taking into account kinetic cloud formation. We apply HST and XMM-Newton/Swift observations obtained by the MOVES programmewhich provide combined X-ray and ultraviolet (XUV) spectra of the host star HD 189733 at 4 different points in time. We find that the differences in the radiation field between the irradiated dayside and the shadowed nightside lead to stronger changes in the chemical abundances than the variability of the host star's XUV emission. We identify ammonium (NH4+) and oxonium (H3O+) as fingerprint ions for the ionization of the atmosphere by both galactic cosmic rays and stellar particles. All considered types of high-energy radiation have an enhancing effect on the abundance of key organic molecules such as hydrogen cyanide (HCN), formaldehyde (CH2O), and ethylene (C2H4). The latter two are intermediates in the production pathway of the amino acid glycine (C2H5NO2) and abundant enough to be potentially detectable by JWST. Ultimately, we show that high energy processes potentially play an important role in prebiotic chemistry.P Barth et al., MOVES IV. Modelling the influence of stellar XUV-flux, cosmic rays, and stellar energetic particles on the atmospheric composition of the hot Jupiter HD&#160;189733b, Monthly Notices of the Royal Astronomical Society, in press, DOI:10.1093/mnras/staa3989

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SNR G39.2−0.3, an hadronic cosmic rays accelerator

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2045 ◽

2020 ◽

Vol 497 (3) ◽

pp. 3581-3590

Author(s):

Emma de Oña Wilhelmi ◽

Iurii Sushch ◽

Robert Brose ◽

Enrique Mestre ◽

Yang Su ◽

...

Keyword(s):

Magnetic Field ◽

Cosmic Rays ◽

Supernova Remnants ◽

Gamma Ray ◽

Spectral Energy Distribution ◽

Galactic Cosmic Rays ◽

Spectral Energy ◽

Core Collapse ◽

Heavy Nuclei ◽

The Rich

ABSTRACT Recent results obtained with gamma-ray satellites have established supernova remnants as accelerators of GeV hadronic cosmic rays. In such processes, CRs accelerated in SNR shocks interact with particles from gas clouds in their surrounding. In particular, the rich medium in which core-collapse SNRs explode provides a large target density to boost hadronic gamma-rays. SNR G39.2–0.3 is one of the brightest SNR in infrared wavelengths, and its broad multiwavelength coverage allows a detailed modelling of its radiation from radio to high energies. We reanalysed the Fermi-LAT data on this region and compare it with new radio observations from the MWISP survey. The modelling of the spectral energy distribution from radio to GeV energies favours a hadronic origin of the gamma-ray emission and constrains the SNR magnetic field to be at least ∼100 µG. Despite the large magnetic field, the present acceleration of protons seems to be limited to ∼10 GeV, which points to a drastic slow down of the shock velocity due to the dense wall traced by the CO observations, surrounding the remnant. Further investigation of the gamma-ray spectral shape points to a dynamically old remnant subjected to severe escape of CRs and a decrease of acceleration efficiency. The low-energy peak of the gamma-ray spectrum also suggests that that the composition of accelerated particles might be enriched by heavy nuclei which is certainly expected for a core-collapse SNR. Alternatively, the contribution of the compressed pre-existing Galactic cosmic rays is discussed, which is, however, found to not likely be the dominant process for gamma-ray production.

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The Origin of the Most Energetic Galactic Cosmic Rays: Supernova Explosions into Massive Star Plasma Winds

Galaxies ◽

10.3390/galaxies7020048 ◽

2019 ◽

Vol 7 (2) ◽

pp. 48 ◽

Cited By ~ 1

Author(s):

Peter L. Biermann ◽

Philipp P. Kronberg ◽

Michael L. Allen ◽

Athina Meli ◽

Eun-Suk Seo

Keyword(s):

Magnetic Field ◽

Cosmic Rays ◽

Field Strength ◽

Magnetic Field Strength ◽

Space Station ◽

Cosmic Ray ◽

High Energy ◽

Galactic Cosmic Rays ◽

Starburst Galaxy ◽

Supergiant Star

We propose that the high energy Cosmic Ray particles up to the upturn commonly called the ankle, from around the spectral turn-down commonly called the knee, mostly come from Blue Supergiant star explosions. At the upturn, i.e., the ankle, Cosmic Rays probably switch to another source class, most likely extragalactic sources. To show this we recently compiled a set of Radio Supernova data where we compute the magnetic field, shock speed and shock radius. This list included both Blue and Red Supergiant star explosions; both data show the same magnetic field strength for these two classes of stars despite very different wind densities and velocities. Using particle acceleration theory at shocks, those numbers can be transformed into characteristic ankle and knee energies. Without adjusting any free parameters both of these observed energies are directly indicated by the supernova data. In the next step in the argument, we use the Supernova Remnant data of the starburst galaxy M82. We apply this analysis to Blue Supergiant star explosions: The shock will race to their outer edge with a magnetic field that is observed to follow over several orders of magnitude B ( r ) × r ∼ c o n s t . , with in fact the same magnetic field strength for such stellar explosions in our Galaxy, and other galaxies including M82. The speed is observed to be ∼0.1 c out to about 10 16 cm radius in the plasma wind. The Supernova shock can run through the entire magnetic plasma wind region at full speed all the way out to the wind-shell, which is of order parsec scale in M82. We compare and identify the Cosmic Ray spectrum in other galaxies, in the starburst galaxy M82 and in our Galaxy with each other; we suggest how Blue Supergiant star explosions can provide the Cosmic Ray particles across the knee and up to the ankle energy range. The data from the ISS-CREAM (Cosmic Ray Energetics and Mass Experiment at the International Space Station) mission will test this cosmic ray concept which is reasonably well grounded in two independent radio supernova data sets. The next step in developing our understanding will be to obtain future more accurate Cosmic Ray data near to the knee, and to use unstable isotopes of Cosmic Ray nuclei at high energy to probe the “piston” driving the explosion. We plan to incorporate these data with the physics of the budding black hole which is probably forming in each of these stars.

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Multi-point galactic cosmic rays measurements between 1 and 4.5 AU over a full Solar cycle

10.5194/angeo-2019-68 ◽

2019 ◽

Author(s):

Thomas Honig ◽

Olivier G. Witasse ◽

Hugh Evans ◽

Petteri Nieminen ◽

Erik Kuulkers ◽

...

Keyword(s):

Cosmic Rays ◽

High Energy ◽

Galactic Cosmic Rays ◽

Radiation Environment ◽

Radiation Data ◽

Rosetta Mission ◽

The Stability ◽

Cross Calibration ◽

Comet 67P

Abstract. The radiation data collected by the Standard Radiation Environment Monitor (SREM) aboard ESA missions INTEGRAl, ROSETTA, HERSCHEL, PLANCK and PROBA-1, and by the High Energy Neutron Detector (HEND) instrument aboard Mars Odyssey are analysed with an emphasis on characterising Galactic Cosmic Rays (GCRs) in the inner heliosphere. A cross-calibration between all sensors was performed for this study, which can also be used in subsequent works. We investigate the stability of the SREM detectors over long-term periods. The radiation data is compared qualitatively and quantitatively with the corresponding solar activity. Based on INTEGRAL and Rosetta SREM data, a GCR helioradial gradient of 2.96 %/AU is found between 1 and 4.5 AU. In addition, the data during the last phase of the Rosetta mission around comet 67P/Churyumov-Gerasimenko were studied in more detail. An unexpected and yet unexplained 8 % reduction of the Galactic Comic Ray flux measured by Rosetta SREM in the vicinity of the comet is noted.

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The Drugs and Natural Antioxidants as the Components of Anti-radiation Countermeasures during Cosmic Flights

Medical Radiology and radiation safety ◽

10.12737/article_59b10b5ea417a6.00174966 ◽

2017 ◽

pp. 66-73 ◽

Cited By ~ 2

Author(s):

И. Ушаков ◽

I. Ushakov ◽

М. Васин ◽

M. Vasin

Keyword(s):

Solar Activity ◽

Cosmic Rays ◽

Radiation Effects ◽

High Energy ◽

Galactic Cosmic Rays ◽

Stress Factors ◽

Solar Cosmic Rays ◽

Post Radiation ◽

The Impact

Radiation situation for cosmonauts over long-term cosmic flights is caused by low-rate radiation of galactic cosmic rays and solar cosmic rays consisting of high-energy proton as well as heavy particles (Z>10) within 1-2 % that is exclusively a threat of stochastic radiation effects (small increase of cancer risk and decrease of mean life span) for men. During interplanetary expedition periods the small probability of raised solar activity there is a threat of exposure to astronauts at doses that cause deterministic radiation effects leading to the development of the disease as a clinical manifestation of radiation injuries,. In a similar scenario it is necessary to have available to cosmic ship anti-radiation countermeasures for cosmonaut protection. Among radioprotective equipment can be provided with radiation protective agents and partial shielding of body separate section providing the best condition for post-radiation repair of radiosensitive body tissues. Preparation B-190 (indralin) is the most perspective from a small numbers of other radioprotectors permitting for men administration. Besides high radioprotective efficacy and large broadness of protective action B-190 is well tolerated including the impact of extrem flight factors. Antiemetic agent latran (ondansetron) is most interesting among preparation for prophylaxis and reduction of prodromal radiation reaction. To accelerate post-radiation hematopoietic recovery after raised solar activity an administration of radiomitigators (riboxin et al.) is substantiated. Neupomax (neupogen) is recommended as a preparation for pathogenesis therapy of acute radiation syndrome. Possible consequences of long-term cosmic voyages for oxidative stress development are taken into consideration. On their basis of nNatural antioxidants, preparations and nutrients radiomodulators, fully qualitative nutrition including vegetable food enriched flavonoids, vitamins C, E and carotene potentially prevent a shorten of cosmonaut biological age induced by solar cosmic rays and galactic cosmic rays and stress factors of long-term cosmic voyages. Radiomodulators are low and non-toxic and have not side effects in recommended doses. Their radioprotective effect is directly induced by adaption reaction on cellular and organismic levels through gene expression modulation and in that way the increase of non-specific body tolerance. The implementation of radiomodulator action is possible through hormesis mechanism.

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