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Related papers: Heliosphere Dimension and Cosmic Ray Modulation

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We constrain the velocity spectral distribution of global-scale solar convective cells at depth using techniques of local helioseismology. We calibrate the sensitivity of helioseismic waves to large-scale convective cells in the interior by…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. M. Hanasoge , T. L. Duvall , M. L. DeRosa

Ultra-high-energy cosmic rays (UHECRs) refer to cosmic rays with energy above 10^{18} eV. UHECR experiments utilize simulations of extensive air shower to estimate the properties of UHECRs. The Telescope Array (TA) experiment employs the…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Soonyoung Roh , Jihee Kim , Katsuaki Kasahara , Eiji Kido , Akimichi Taketa , Dongsu Ryu , Hyesung Kang

Cosmic rays are an essential ingredient in the evolution of the interstellar medium, as they dominate the ionisation of the dense molecular gas, where stars and planets form. However, since they are efficiently scattered by the galactic…

Astrophysics of Galaxies · Physics 2014-09-05 Solenn Vaupré , Pierre Hily-Blant , Cecilia Ceccarelli , Guillaume Dubus , Stefano Gabici , Thierry Montmerle

Diffuse interstellar clouds show large abundances of H_3^+ which can be maintained only by a high ionization rate of H_2. Cosmic rays are the dominant ionization mechanism in this environment, so the large ionization rate implies a high…

High Energy Astrophysical Phenomena · Physics 2011-02-11 Nick Indriolo , Brian D. Fields , Benjamin J. McCall

We study the influence of the spatial resolution on scales of $5\deg$ and smaller of solar surface magnetic field maps on global magnetohydrodynamic solar wind models, and on a model of coronal heating and X-ray emission. We compare the…

Solar and Stellar Astrophysics · Physics 2013-05-13 C. Garraffo , O. Cohen , J. J. Drake , C. Downs

Using simulation methods, distortion effects on energy spectra caused by errors in the energy determination have been investigated. For cosmic ray proton spectra, falling steeply with kinetic energy E as E-2.7, significant effects appear.…

Astrophysics · Physics 2009-11-11 Per Carlson , Conny Wannemark

From a broader perspective, the heliosphere and planetary magnetospheres provide a test bed to explore the plasma physics of the Universe. In particular, the underlying nonlinear coupling of different spatial and temporal scales plays a key…

Space Physics · Physics 2010-05-27 Dastgeer Shaikh , I. S. Veselovsky , Q. M. Lu , G. P. Zank

Doppler imaging spectroscopy is the most reliable way to directly measure wind speeds of planetary atmospheres of the Solar system. However, most knowledge about atmospheric dynamics has been obtained with cloud-tracking technique, which…

Earth and Planetary Astrophysics · Physics 2019-06-14 Patrick Gaulme , Francois-Xavier Schmider , Ivan Goncalves

During the propagation of cosmic rays in the solar system, the Sun will block those particles and form a shadow whose position and depth are very important probe of the magnetic fields in the Sun's corona, in the interplanetary space, and…

High Energy Astrophysical Phenomena · Physics 2026-05-19 Jie Xia , Ming-Yang Cui , Qiang Yuan , Yi Zhang , Guang-Lu Shi , Li Feng

Isotropic diffusion models for Galactic cosmic ray transport put tight constraints on the maximum convection velocity in the halo. For a half halo height of 4 kpc the maximum convection speed is limited to 40 km/s in the halo, since…

Astrophysics of Galaxies · Physics 2009-10-13 Iris Gebauer , Wim de Boer

We investigate effects of cosmic-rays on the linear growth of the Kelvin-Helmholtz instability. Cosmic-rays are treated as an adiabatic gas and allowed to diffuse along magnetic field lines. We calculated the dispersion relation of the…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Akihiro Suzuki , Hiroyuki R. Takahashi , Takahiro Kudoh

Nowadays, the calculation of the Galactic Cosmic Rays diffusion coefficient with direct microscopic numerical simulations is a widespread approach. In this work, we investigated the numerical limits for such calculations and demonstrated…

Instrumentation and Methods for Astrophysics · Physics 2026-05-14 Vladimir Yurovsky , Ilya Kudryashov

The energy spectrum of ultra-high energy cosmic rays above 10$^{18}$ eV is measured using the hybrid events collected by the Pierre Auger Observatory between November 2005 and September 2010. The large exposure of the Observatory allows the…

High Energy Astrophysical Phenomena · Physics 2016-06-15 Mariangela Settimo

There is a growing set of observational data demonstrating that cosmic rays exhibit small-scale anisotropies (5-30 deg) with amplitude deviations lying between 0.01-0.1 percent that of the average cosmic ray flux. A broad range of models…

High Energy Astrophysical Phenomena · Physics 2021-01-20 Margot Fitz Axen , Julia Speicher , Aimee Hungerford , Chris L. Fryer

We develop a fully three dimensional numerical code describing the diffusion of cosmic rays in the Milky Way. It includes the nuclear spallation chain up to Oxygen, and allows the study of various cosmic ray properties, such as the CR age,…

Astrophysics of Galaxies · Physics 2017-11-10 David Benyamin , Ehud Nakar , Tsvi Piran , Nir J. Shaviv

Magnetic fields of laboratory, planetary, stellar, and galactic plasmas commonly exhibit significant order on large temporal or spatial scales compared to the otherwise random motions within the hosting system. Such ordered fields can be…

Solar and Stellar Astrophysics · Physics 2015-06-18 Eric G. Blackman

We discuss the influence of large scale cosmic magnetic fields on the propagation of hadronic cosmic rays above 10^19 eV based on large scale structure simulations. Our simulations suggest that rather substantial deflection up to several…

Astrophysics · Physics 2009-11-10 Guenter Sigl , Francesco Miniati , Torsten Ensslin

The variation in the intensity of cosmic rays at small angular scales is attributed to the interstellar turbulence in the vicinity of the Solar system. We show that {a turbulent origin of the small-scale structures implies that} the…

High Energy Astrophysical Phenomena · Physics 2018-12-12 Rahul Kumar , Noemie Globus , David Eichler , Martin Pohl

The nocturnal mesopause region of the Earth's atmosphere radiates chemiluminescent emission from various roto-vibrational bands of hydroxyl (OH), which is therefore a good tracer of the chemistry and dynamics at the emission altitudes.…

Atmospheric and Oceanic Physics · Physics 2023-05-04 Stefan Noll , Carsten Schmidt , Wolfgang Kausch , Michael Bittner , Stefan Kimeswenger

Large-scale velocity fields in the solar photosphere remain a mystery in spite of many years of intensive studies. In this thesis, the new method of the measurements of the solar photospheric flow fields is proposed. It is based on local…

Astrophysics · Physics 2007-12-13 Michal Svanda
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