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Journal articles on the topic 'Galactic proton'

Author: Grafiati

Published: 1 April 2023

Last updated: 31 July 2025

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1

Sikora, Marek, Bronisław Rudak, and Mitchell Begelman. "Relativistic Neutrons in Active Galactic Nuclei." Symposium - International Astronomical Union 134 (1989): 215–16. http://dx.doi.org/10.1017/s0074180900140902.

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A substantial fraction of the radiation from an active galactic nucleus (AGN) is apparently nonthermal in origin, and is probably produced by ultrarelativistic electrons. How much energy goes into relativistic protons is uncertain, but it is likely to be comparable to the electron energy or larger. Indeed, several authors (Sikora et al. 1987; Kazanas and Ellison 1986; Zdziarski 1986) have shown that proton-photon and proton-proton collisions can be efficient sources of relativistic pairs in the central engine of an AGN. Thus it is not necessary for electrons to be accelerated directly in AGNs,

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2

Fiandrini, E., B. Bertucci, N. Tomassetti, and B. Khiali. "New solar modulation modeling of the galactic proton flux measured by the AMS02 and PAMELA experiments." EPJ Web of Conferences 209 (2019): 01032. http://dx.doi.org/10.1051/epjconf/201920901032.

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A thorough understanding of solar effects on the galactic cosmic rays is relevant both to infer the local interstellar spectrum characteristics and to investigate the dynamics of charged particles in the heliosphere. We present a newly developed numerical modulation model to study the transport of galactic protons in the heliosphere. The model was applied to the 27-day averaged galactic proton flux recently released by the PAMELA and AMS02 experiments, covering an extended time period from mid-2006 to mid-2017.

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Jansen, F., K. P. Wenzel, D. O' Sullivan, and A. Thompson. "The Bulge of the Milky Way and cosmic rays." Symposium - International Astronomical Union 153 (1993): 283–84. http://dx.doi.org/10.1017/s0074180900123265.

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The propagation of cosmic ray protons and anti–protons from the inner Galaxy via the galactic halo to the Sun supplies a good agreement with the observed cosmic ray gradient and is in the order of the measured anti-proton flux. Ultra heavy cosmic ray nuclei may have the same origin.

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4

Buchvarova, M., and P. Velinov. "Cosmic ray spectra in planetary atmospheres." Proceedings of the International Astronomical Union 4, S257 (2008): 471–73. http://dx.doi.org/10.1017/s1743921309029718.

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AbstractOur model generalizes the differential D(E) and integral D(>E) spectra of cosmic rays (CR) during the 11-year solar cycle. The empirical model takes into account galactic (GCR) and anomalous cosmic rays (ACR) heliospheric modulation by four coefficients. The calculated integral spectra in the outer planets are on the basis of mean gradients: for GCR – 3%/AU and 7%/AU for anomalous protons. The obtained integral proton spectra are compared with experimental data, the CRÈME96 model for the Earth and theoretical results of 2D stochastic model. The proposed analytical model gives practi

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5

Abdollahi, S., F. Acero, M. Ackermann, et al. "Search for New Cosmic-Ray Acceleration Sites within the 4FGL Catalog Galactic Plane Sources." Astrophysical Journal 933, no. 2 (2022): 204. http://dx.doi.org/10.3847/1538-4357/ac704f.

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Abstract Cosmic rays are mostly composed of protons accelerated to relativistic speeds. When those protons encounter interstellar material, they produce neutral pions, which in turn decay into gamma-rays. This offers a compelling way to identify the acceleration sites of protons. A characteristic hadronic spectrum, with a low-energy break around 200 MeV, was detected in the gamma-ray spectra of four supernova remnants (SNRs), IC 443, W44, W49B, and W51C, with the Fermi Large Area Telescope. This detection provided direct evidence that cosmic-ray protons are (re-)accelerated in SNRs. Here, we p

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Papavasileiou, Theodora, Odysseas Kosmas, and Ioannis Sinatkas. "Studying the Spectral Energy Distributions Emanating from Regular Galactic XRBs." Universe 9, no. 7 (2023): 312. http://dx.doi.org/10.3390/universe9070312.

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X-ray binary systems (XRBs) exhibit similar dynamics and multimessenger emission mechanisms to active galactic nuclei (AGNs) with the benefit of shorter time scaling. Those systems produce rich spectral energy distributions (SEDs) ranging from the radio band to the very high energy gamma rays. The emission origin varies between the system’s accretion disk (X-rays) to the corona and, most notably, to the two twin plasma ejections (jets) that often meet the interstellar medium forming highly observable radio lobes. Modeling of the jets offers an excellent opportunity to understand the intrinsic

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7

Song, Xiaojian, and Xi Luo. "The Implication of the Helium-to-proton Flux Ratio in Galactic Cosmic Rays." Astrophysical Journal 959, no. 2 (2023): 139. http://dx.doi.org/10.3847/1538-4357/ad0b09.

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Abstract The measurement of daily proton and helium fluxes by AMS-02 shows that the helium-to-proton flux ratio (He/H) is negatively correlated with the solar activity at rigidity 1.7–7 GV. What is the behavior of He/H at rigidity lower than 1.7 GV? How can this phenomenon be described quantitatively and linked to the underlying mechanisms? In this work, based on a theoretical derivation, we find that the slope (S) of ln ( He / H ) versus ln(H) is a good indicator of the variation of He/H. S > 0 means the variation of He/H is anticorrelated with the solar activity, and vice versa. Furthermo

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Fang, Jun, Qi Xia, Shiting Tian, Liancheng Zhou, and Huan Yu. "Kinetic simulation of electron, proton and helium acceleration in a non-relativistic quasi-parallel shock." Monthly Notices of the Royal Astronomical Society 512, no. 4 (2022): 5418–22. http://dx.doi.org/10.1093/mnras/stac886.

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ABSTRACT In addition to accelerating electrons and protons, non-relativistic quasi-parallel shocks are expected to possess the ability to accelerate heavy ions. The shocks in supernova remnants are generally supposed to be accelerators of Galactic cosmic rays, which consist of many species of particles. We investigate the diffusive shock acceleration of electrons, protons and helium ions in a non-relativistic quasi-parallel shock through a 1D particle-in-cell simulation with a helium-to-proton number density ratio of 0.1, which is relevant for Galactic cosmic rays. The simulation indicates tha

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9

Khokhlov, Dmitri L. "Planck Neutrinos as Ultra High Energy Cosmic Rays." Open Astronomy 29, no. 1 (2020): 40–46. http://dx.doi.org/10.1515/astro-2020-0005.

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AbstractThe studied conjecture is that ultra high energy cosmic rays (UHECRs) are hypothetical Planck neutrinos arising in the decay of the protons falling onto the gravastar. The proton is assumed to decay at the Planck scale into positron and four Planck neutrinos. The supermassive black holes inside active galactic nuclei, while interpreted as gravastars, are considered as UHECR sources. The scattering of the Planck neutrinos by the proton at the Planck scale is considered. The Planck neutrinos contribution to the CR events may explain the CR spectrum from 5 × 1018 eV to 1020 eV. The muon n

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10

Werhahn, Maria, Christoph Pfrommer, Philipp Girichidis, Ewald Puchwein, and Rüdiger Pakmor. "Cosmic rays and non-thermal emission in simulated galaxies − I. Electron and proton spectra compared to Voyager-1 data." Monthly Notices of the Royal Astronomical Society 505, no. 3 (2021): 3273–94. http://dx.doi.org/10.1093/mnras/stab1324.

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ABSTRACT Current-day cosmic ray (CR) propagation studies use static Milky Way models and fit parametrized source distributions to data. Instead, we use three-dimensional magnetohydrodynamic (MHD) simulations of isolated galaxies with the moving-mesh code arepo that self-consistently accounts for hydrodynamic effects of CR protons. In post-processing, we calculate their steady-state spectra, taking into account all relevant loss processes. We show that this steady-state assumption is well justified in the disc and generally for regions that emit non-thermal radio and gamma rays. Additionally, w

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11

Mastichiadis, Apostolos, Ioulia Florou, Elina Kefala, Stella S. Boula, and Maria Petropoulou. "A roadmap to hadronic supercriticalities: a comprehensive study of the parameter space for high-energy astrophysical sources." Monthly Notices of the Royal Astronomical Society 495, no. 2 (2020): 2458–74. http://dx.doi.org/10.1093/mnras/staa1308.

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ABSTRACT Hadronic supercriticalities are radiative instabilities that appear when large amounts of energy are stored in relativistic protons. When the proton energy density exceeds some critical value, a runaway process is initiated resulting in the explosive transfer of the proton energy into electron–positron pairs and radiation. The runaway also leads to an increase of the radiative efficiency, namely the ratio of the photon luminosity to the injected proton luminosity. We perform a comprehensive study of the parameter space by investigating the onset of hadronic supercriticalities for a wi

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12

Casolino, Marco, N. De Simone, and V. Formato. "PAMELA recent results on galactic proton and helium." Nuclear Physics B - Proceedings Supplements 212-213 (March 2011): 362–67. http://dx.doi.org/10.1016/j.nuclphysbps.2011.03.049.

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13

HEINZ, SEBASTIAN. "CLUES FOR THE COMPOSITION OF RELATIVISTIC MICROQUASAR JETS." International Journal of Modern Physics D 17, no. 10 (2008): 1947–52. http://dx.doi.org/10.1142/s0218271808013613.

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We discuss the evidence for proton loading in relativistic jets from microquasars in light of recent constraints on the jet power. We argue that, both in the case of the Cygnus X-1 jet and the entire ensemble of Galactic microquasars, the evidence points towards a significant contribution to the total kinetic energy flux from cold protons. However, as with all other methods of constraining jet composition (except for the singular case of SS 433), a number of alternative, though maybe less plausible, explanations exist. In light of this continued elusiveness of a single slam-dunk argument for p

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14

Fokov, Gennadiy, and Valeriy Kozhemyakin. "On the Calibration of the Cherenkov Detector of Galactic and Solar Cosmic Protons with Energies of 600 MeV and More." ANRI, no. 1 (March 4, 2021): 53–62. http://dx.doi.org/10.37414/2075-1338-2021-104-1-53-62.

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This article discusses a possible approach to creating a calibration technique for the Galactic and Solar Cosmic Proton Cherenkov Detector. The method is based on the Monte Carlo simulation of proton and electron transfer and their generation of Cherenkov photons in the polymethylmethacrylate radiator. It is shown that, under certain conditions, the device calibration with electrons of 9,38 MeV energy is equivalent to the calibration with a 600 MeV proton beam incident laterally on the detector.

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15

Tsuji, Naomi, Takaaki Tanaka, Samar Safi-Harb, et al. "Search for Synchrotron Emission from Secondary Electrons of Proton–Proton Interactions in Galactic PeVatron Candidate HESS J1641–463." Astrophysical Journal 967, no. 2 (2024): 138. http://dx.doi.org/10.3847/1538-4357/ad3fb1.

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Abstract HESS J1641−463 is an unidentified gamma-ray source with a hard TeV gamma-ray spectrum, and thus it has been proposed to be a possible candidate for a cosmic-ray (CR) accelerator up to PeV energies (a PeVatron candidate). The source spatially coincides with the radio supernova remnant G338.5+0.1 but has not yet been fully explored in the X-ray band. We analyzed newly taken NuSTAR data, pointing at HESS J1641−463, with 82 ks effective exposure time. There is no apparent X-ray counterpart of HESS J1641−463, while nearby stellar cluster, Mercer 81, and stray-light X-rays are detected. Com

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16

Blandford, Roger, David Meier, and Anthony Readhead. "Relativistic Jets from Active Galactic Nuclei." Annual Review of Astronomy and Astrophysics 57, no. 1 (2019): 467–509. http://dx.doi.org/10.1146/annurev-astro-081817-051948.

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The nuclei of most normal galaxies contain supermassive black holes, which can accrete gas through a disk and become active. These active galactic nuclei (AGNs) can form jets that are observed on scales from astronomical units to megaparsecs and from meter wavelengths to TeV energies. High-resolution radio imaging and multiwavelength/messenger campaigns are elucidating the conditions under which this happens. Evidence is presented that: ▪ Relativistic AGN jets are formed when the black hole spins and the the accretion disk is strongly magnetized, perhaps on account of gas accreting at high lat

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17

Vecchiotti, V., F. L. Villante, and G. Pagliaroli. "Unveiling the Nature of Galactic TeV Sources with IceCube Results." Astrophysical Journal Letters 956, no. 2 (2023): L44. http://dx.doi.org/10.3847/2041-8213/acff60.

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Abstract IceCube collaboration reported the first high-significance observation of the neutrino emission from the Galactic disk. The observed signal can be due to diffuse emission produced by cosmic rays interacting with interstellar gas but can also arise from a population of sources. In this paper, we evaluate both the diffuse and source contribution by taking advantage of gamma-ray observations and/or theoretical considerations. By comparing our expectations with IceCube measurements, we constrain the fraction of Galactic TeV gamma-ray sources (resolved and unresolved) with hadronic nature.

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18

Supan, L., G. Castelletti, A. D. Supanitsky, M. G. Burton, G. F. Wong, and C. Braiding. "Natal molecular cloud of SNR Kes 41. Complete characterisation." Astronomy & Astrophysics 619 (November 2018): A108. http://dx.doi.org/10.1051/0004-6361/201833183.

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Using high-resolution data of the 12CO and 13CO (J = 1–0) line emission from the Mopra Southern Galactic Plane CO Survey in conjunction with neutral hydrogen observations from the Southern Galactic Plane Survey (SGPS) and mid-infrared Spitzer data, we have explored the large-scale environment of the supernova remnant Kes 41. On the basis of these data, we identified for the first time the parent cloud of Kes 41 in its whole extension and surveyed the HII regions, masers, and the population of massive young stellar objects in the cloud. The whole unveiled giant cloud, located at the kinematic d

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19

Mitrikas, V. G. "Radiation Aspect of Two Orbit Inclination Options of the Russian Orbital Service Station." Космические исследования 61, no. 2 (2023): 157–62. http://dx.doi.org/10.31857/s0023420622700030.

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The contribution to the effective dose from cosmic radiation of the Earth’s radiation belts, galactic cosmic rays, and solar proton events for astronauts located in the large-diameter working compartment of the service module of the ISS is considered. It is shown that for quasi-stationary sources of cosmic radiation, a change in the orbital inclination of 51.6° by 97.0° does not lead to significant variations in the average daily effective dose rate. When considering the contribution to the effective dose from solar-flare protons, the dose load on astronauts can increase by ten or more times.

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20

Loffredo, Filomena, Emanuele Vardaci, Davide Bianco, Antonio Di Nitto, and Maria Quarto. "Protons Interaction with Nomex Target: Secondary Radiation from a Monte Carlo Simulation with Geant4." Applied Sciences 12, no. 5 (2022): 2643. http://dx.doi.org/10.3390/app12052643.

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The study of suitable materials to shield astronauts from Galactic Cosmic Rays (GCR) is a topic of fundamental importance. The choice of the material must take into account both the secondary radiation produced by the interaction between primary radiation and material and its shielding ability. The physics case presented here deals with the interaction of a proton beam with a Nomex shield, namely, a target material with a mass thickness of 20 g cm−2. The study was conducted with the simulation code DOSE based on the well-known simulation package Geant4. This article shows the properties of sec

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Adagba B A, G. "Comparison of Galactic Cosmic Ray Proton and Helium Spectra: Unraveling the Nuances of High - Energy Particle Acceleration." International Journal of Science and Research (IJSR) 12, no. 5 (2023): 1498–502. http://dx.doi.org/10.21275/sr23512122821.

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22

Begelman, Mitchell C., Bronislaw Rudak, and Marek Sikora. "Consequences of relativistic proton injection in active galactic nuclei." Astrophysical Journal 362 (October 1990): 38. http://dx.doi.org/10.1086/169241.

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23

Yang, Rui-Zhi, and Yuan Wang. "The diffuse gamma-ray emission toward the Galactic mini starburst W43." Astronomy & Astrophysics 640 (August 2020): A60. http://dx.doi.org/10.1051/0004-6361/202037518.

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In this paper we report the Fermi Large Area Telescope (Fermi-LAT) detection of the γ-ray emission toward the young star forming region W43. Using the latest source catalog and diffuse background models, the extended γ-ray excess is detected with a significance of ~16σ. The γ-ray emission has a spectrum with a photon index of 2.3 ± 0.1. We also performed a detailed analysis of the gas content in this region by taking into account the opacity correction to the HI gas column density. The total cosmic-ray (CR) proton energy is estimated to be on the order of 1048 erg, assuming the γ-rays are prod

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24

Dey, Rajat K., Animesh Basak, and Sabyasachi Ray. "Diffuse flux of PeV neutrinos from centrifugally accelerated protons in active galactic nuclei." Europhysics Letters 136, no. 6 (2021): 69001. http://dx.doi.org/10.1209/0295-5075/ac35bc.

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Abstract Evidence for high-energy astrophysical PeV neutrinos has been found in the IceCube experiment from an analysis with 7.5-year (2010–2017) data. Active galactic nuclei (AGN) are among the most prominent objects in the universe, and are widely speculated to be emitters of ultra-high-energy (UHE) cosmic rays with proton domination. Based on the standard two-step LLCD mechanism of particle acceleration, a transformation of energy occurs from AGN's central super-massive black hole (SMBH) rotation to high-energy protons. Protons can be accelerated up to energies and above, and might generate

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Begelman, Mitchell C., Bronislaw Rudak, and Marek Sikora. "Consequences of Relativistic Proton Injection in Active Galactic Nuclei: Erratum." Astrophysical Journal 370 (April 1991): 791. http://dx.doi.org/10.1086/169863.

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An, Q., R. Asfandiyarov, P. Azzarello, et al. "Measurement of the cosmic ray proton spectrum from 40 GeV to 100 TeV with the DAMPE satellite." Science Advances 5, no. 9 (2019): eaax3793. http://dx.doi.org/10.1126/sciadv.aax3793.

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The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 1/2 years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments

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Klinger, Marc, Annika Rudolph, Xavier Rodrigues, et al. "AM³: An Open-source Tool for Time-dependent Lepto-hadronic Modeling of Astrophysical Sources." Astrophysical Journal Supplement Series 275, no. 1 (2024): 4. http://dx.doi.org/10.3847/1538-4365/ad725c.

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Abstract We present the Astrophysical Multimessenger Modeling (AM 3 ) software. AM 3 is a documented open-source software (source code at https://gitlab.desy.de/am3/am3; user guide and documentation at https://am3.readthedocs.io/en/latest/) that efficiently solves the coupled integro-differential equations describing the temporal evolution of the spectral densities of particles interacting in astrophysical environments, including photons, electrons, positrons, protons, neutrons, pions, muons, and neutrinos. The software has been extensively used to simulate the multiwavelength and neutrino emi

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Su 苏, Renzhi 仁智, Tao An, Stephen J. Curran, Michael P. Busch, Minfeng Gu, and Di Li. "Constraints on the Fractional Changes of the Fundamental Constants at a Look-back Time of 2.5 Myr." Astrophysical Journal Letters 981, no. 2 (2025): L25. https://doi.org/10.3847/2041-8213/adb843.

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Abstract The quantum nature of gravity remains one of the greatest mysteries of modern physics, with many unified theories predicting variations in fundamental constants across space and time. Here we present precise measurements of these variations at galactic dynamical timescales—a critical but previously unexplored regime. Using simultaneous observations of H i and OH lines in M31, we probe potential variations of fundamental constants at a look-back time of 2.5 million yr. We obtained Δ ( μ α 2 g p 0.64 ) / ( μ α 2 g p 0.64 ) < 3.6 × 1 0 − 6 , with complementary constraints on Δ(μα 2)/(

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Dörner, Julien, Leonel Morejon, Karl-Heinz Kampert, and Julia Becker Tjus. "Uncertainties in astrophysical gamma-ray and neutrino fluxes from proton-proton cross-sections in the GeV to PeV range." Journal of Cosmology and Astroparticle Physics 2025, no. 04 (2025): 043. https://doi.org/10.1088/1475-7516/2025/04/043.

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Abstract The identification of Cosmic Ray (CR) sources represents one of the biggest and long-standing questions in astrophysics. Direct measurements of cosmic rays cannot provide directional information due to their deflection in (extra)galactic magnetic fields. Cosmic-ray interactions at the sources lead to the production of high-energy gamma rays and neutrinos, which, combined in the multimessenger picture, are the key to identifying the origins of CRs and estimating transport properties. While gamma-ray observations alone raise the question of whether their origin is hadronic or leptonic,

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De Benedittis, Antonio. "Proton energy spectrum with the DAMPE experiment." EPJ Web of Conferences 209 (2019): 01030. http://dx.doi.org/10.1051/epjconf/201920901030.

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The DAMPE (DArk Matter Particle Explorer) experiment, in orbit since December 17th 2015, is a space mission whose main purpose is the detection of cosmic electrons and photons up to energies of 10 TeV, in order to identify possible evidence of Dark Matter in their spectra. Furthermore it aims to measure the spectra and the elemental composition of the galactic cosmic rays nuclei up to the energy of hundreds of TeV. The proton analysis and the flux with kinetic energy ranging from 50 GeV up to 100 TeV, at the end of two years of data taking, will be presented and discussed.

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Persinger, Michael A. "Annual Fluctuations in Local Photon Counts Reflect Differential Distances from the Galaxy’s Singularity: Astronomical, Chemical and Biology Implications." International Letters of Chemistry, Physics and Astronomy 49 (April 2015): 60–65. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.49.60.

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A conspicuous annual variation in the photon flux density of ~10-12 W·m-2 by a photomultiplier tube housed in a hyperdark ground level setting was within the range expected for the small changes in the earth’s distance per orbit from the energetic entropy (Joules) of the singularity at the center of the galaxy. For the Bekenstein-Hawking relation to be congruent the singularity’s power must reflect the galaxy’s age. The power (W) per volume at the distance of the earth when divided into the peak-to-trough change in photon flux density for minimum-maximum distances from the galactic center conv

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Persinger, Michael A. "Annual Fluctuations in Local Photon Counts Reflect Differential Distances from the Galaxy’s Singularity: Astronomical, Chemical and Biology Implications." International Letters of Chemistry, Physics and Astronomy 49 (April 7, 2015): 60–65. http://dx.doi.org/10.56431/p-x78dwz.

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A conspicuous annual variation in the photon flux density of ~10-12 W·m-2 by a photomultiplier tube housed in a hyperdark ground level setting was within the range expected for the small changes in the earth’s distance per orbit from the energetic entropy (Joules) of the singularity at the center of the galaxy. For the Bekenstein-Hawking relation to be congruent the singularity’s power must reflect the galaxy’s age. The power (W) per volume at the distance of the earth when divided into the peak-to-trough change in photon flux density for minimum-maximum distances from the galactic center conv

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Albert, A., R. Alfaro, C. Alvarez, et al. "Observation of the Galactic Center PeVatron beyond 100 TeV with HAWC." Astrophysical Journal Letters 973, no. 1 (2024): L34. http://dx.doi.org/10.3847/2041-8213/ad772e.

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Abstract We report an observation of ultrahigh-energy (UHE) gamma rays from the Galactic center (GC) region, using 7 yr of data collected by the High-Altitude Water Cherenkov (HAWC) Observatory. The HAWC data are best described as a point-like source (HAWC J1746-2856) with a power-law spectrum ( d N / d E = ϕ E / 26 TeV γ ), where γ = −2.88 ± 0.15stat − 0.1sys and ϕ = 1.5 × 10−15 (TeV cm2 s)−1 ± 0.3 stat − 0.13 sys + 0.08 sys extending from 6 to 114 TeV. We find no evidence of a spectral cutoff up to 100 TeV using HAWC data. Two known point-like gamma-ray sources are spatially coincident with

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34

Neronov, A., and D. Semikoz. "Radio-to-Gamma-Ray Synchrotron and Neutrino Emission from Proton–Proton Interactions in Active Galactic Nuclei." JETP Letters 113, no. 2 (2021): 69–74. http://dx.doi.org/10.1134/s0021364021020028.

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Aminalragia-Giamini, Sigiava, Ingmar Sandberg, Constantinos Papadimitriou, Ioannis A. Daglis, and Piers Jiggens. "The virtual enhancements − solar proton event radiation (VESPER) model." Journal of Space Weather and Space Climate 8 (2018): A06. http://dx.doi.org/10.1051/swsc/2017040.

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A new probabilistic model introducing a novel paradigm for the modelling of the solar proton environment at 1 AU is presented. The virtual enhancements − solar proton event radiation model (VESPER) uses the European space agency's solar energetic particle environment modelling (SEPEM) Reference Dataset and produces virtual time-series of proton differential fluxes. In this regard it fundamentally diverges from the approach of existing SPE models that are based on probabilistic descriptions of SPE macroscopic characteristics such as peak flux and cumulative fluence. It is shown that VESPER repr

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Persinger, Michael A. "Variability of Hubble’s Parameter, Geomagnetic Activity, and Putative Changes in Space-Mass Density: Implications for Terrestrial Cell Growth." International Letters of Chemistry, Physics and Astronomy 53 (July 2015): 137–45. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.53.137.

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The quotient for Planck’s Length divided by the product of Hubble’s parameter and twice the width of the Compton wave length for a proton has been considered a critical increment for the time required for a proton to expand one Planck’s Length. The empirical time of 3.25 ms, found in magnetic field effectiveness for multiple physical and biochemical reactions, requires a local Hubble constant (H) of 58 km·s-1·MPar-1 with a resulting mass density of 0.14 protons per cubic meter. This mass density multiplied by the cube of the galactic orbital velocity is within error measurement of the backgrou

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Persinger, Michael A. "Variability of Hubble’s Parameter, Geomagnetic Activity, and Putative Changes in Space-Mass Density: Implications for Terrestrial Cell Growth." International Letters of Chemistry, Physics and Astronomy 53 (July 1, 2015): 137–45. http://dx.doi.org/10.56431/p-w3lm9u.

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The quotient for Planck’s Length divided by the product of Hubble’s parameter and twice the width of the Compton wave length for a proton has been considered a critical increment for the time required for a proton to expand one Planck’s Length. The empirical time of 3.25 ms, found in magnetic field effectiveness for multiple physical and biochemical reactions, requires a local Hubble constant (H) of 58 km·s-1·MPar-1 with a resulting mass density of 0.14 protons per cubic meter. This mass density multiplied by the cube of the galactic orbital velocity is within error measurement of the backgrou

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Cirkovic, Milan, and I. Damjanov. "On determination of the cosmic ray flux using molecular hydrogen absorption lines." Serbian Astronomical Journal, no. 167 (2003): 15–20. http://dx.doi.org/10.2298/saj0367015c.

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We outline a procedure for estimating the cosmic ray flux at remote locations where molecular hydrogen absorption lines have been detected. The method relies on several assumptions whose validity in the local Galactic ISM has been independently verified, so it might be useful for much less accessible objects, especially damped Ly? absorption systems. Since most of low-energy cosmic rays in the Galactic environment are thought to originate in supernovae remnants, the link to the rate of high-mass star formation could in principle, be established. We applied the method to a particular case of hi

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Takahashi, Yoshiyuki. "Chemical Composition of High-Energy Cosmic-Ray Nuclei and its Possible Origin in Type-II Supernova." International Astronomical Union Colloquium 108 (1988): 444–45. http://dx.doi.org/10.1017/s0252921100094343.

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High energy cosmic ray spectrum has been known to have an interesting bump in the energy range 1014 − 1016 eV. Various models to explain the spectral break in this energy range have been so far proposed; which incorporate either a large-scale termination of galactic wind, shocks with greater age and spatial extent associated with hypothetical super-bubbles powered by multiple supernovae, intersection of two quantum-gravitational components, extra-galactic component, red-shift of big-bang remnant, or a proton component from pulsars. More recently, their possible origin in type-II supernovae wit

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Lazutin, Leonid. "INCREASES IN SCR ENERGETIC PROTON FLUXES ON EARTH AND THEIR RELATION TO SOLAR SOURCES." Solar-Terrestrial Physics 6, no. 4 (2020): 40–43. http://dx.doi.org/10.12737/stp-64202006.

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Logachev catalog data for solar cycle 23 has been used to study the dependence of measured increases in solar cosmic rays (SCRs) on solar perturbations. The efficiency of recording the SCR increases, driven by proton acceleration in the corona, on Earth and in its vicinity is shown to depend on power of a solar flare that created a shock wave and on position of the flare on the solar disk. As the particle flux moves along the heliolongitude away from the parent flare, the acceleration efficiency decreases, i.e. the maximum energy of the accelerated particles and their intensity at equal energy

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Liang, Xuan-Han, Xiao-Bin Chen, Ben Li, Ruo-Yu Liu, and Xiang-Yu Wang. "Potential Contribution of Young Pulsar Wind Nebulae to Galactic High-energy Neutrino Emission." Astrophysical Journal 983, no. 2 (2025): 170. https://doi.org/10.3847/1538-4357/adbe77.

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Abstract Pulsar wind nebulae (PWNe), especially the young ones, are among the most energetic astrophysical sources in the Galaxy. It is usually believed that the spin-down energy injected from the pulsars is converted into magnetic field and relativistic electrons, but the possible presence of proton acceleration inside PWNe cannot be ruled out. Previous works have estimated the neutrino emission from PWNe using various source catalogs measured in gamma rays. However, some sources may be unresolved due to the limited sensitivity of TeV gamma-ray observations, while part of the unidentified sou

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Aharonian, F. A. "Proton-synchrotron radiation of large-scale jets in active galactic nuclei." Monthly Notices of the Royal Astronomical Society 332, no. 1 (2002): 215–30. http://dx.doi.org/10.1046/j.1365-8711.2002.05292.x.

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Mori, Masaki. "The Galactic Diffuse Gamma‐Ray Spectrum from Cosmic‐Ray Proton Interactions." Astrophysical Journal 478, no. 1 (1997): 225–32. http://dx.doi.org/10.1086/303785.

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Vorotyntseva, J. S., and S. A. Levshakov. "Indication of the Electron-to-Proton Mass Ratio Variation in the Galaxy." JETP Letters 121, no. 8 (2025): 589–94. https://doi.org/10.1134/s0021364025606025.

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Near (~100 pc) and far (~8.7 kpc) relative to the Galactic center, the molecular clouds SgrB2(N) and Orion-KL exhibit different values of the fundamental physical constant μ = m e /m p , which is the electron-to-proton mass ratio. Measured frequency difference between the emission lines of methanol (CH3OH), $${{J}_{{{{K}_{u}}}}}$$ → $${{J}_{{{{K}_{\ell }}}}}$$ = 63 → 52 A + 542 000.981 MHz, 63 → 52 A – 542 081.936 MHz, and 80 → 7–1 E 543 076.194 MHz, observed with the space observatory Herschel toward SgrB2(N) and Orion-KL corresponds to (Sgr-Ori): Δμ/μ = (‒3.7 ± 0.5) × 10–7 (1σ C.L.). At the

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Buchvarova, M. "Semi-empirical model of galactic cosmic ray spectrum." Journal of Physics: Conference Series 2668, no. 1 (2023): 012004. http://dx.doi.org/10.1088/1742-6596/2668/1/012004.

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Abstract The galactic cosmic rays are high-energy particles that reach us from all directions of the vast universe. Their transport in the interplanetary medium is well described by the transport equation, first derived by Parker in 1965. An approximate solution of the cosmic ray transport equation for 1 AU is used to construct a simplified, semi-empirical model of the cosmic ray spectrum. The model parameters are obtained by fitting the proton spectra of the PAMELA experiment. The values of the model parameters are presented for the period 2006-2014, which includes the solar minimum between c

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Song, Xiaojian, Xi Luo, Marius S. Potgieter, XinMing Liu, and Zekun Geng. "A Numerical Study of the Solar Modulation of Galactic Protons and Helium from 2006 to 2017." Astrophysical Journal Supplement Series 257, no. 2 (2021): 48. http://dx.doi.org/10.3847/1538-4365/ac281c.

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Abstract With continuous measurements from space-borne cosmic-ray detectors such as AMS-02 and PAMELA, precise spectra of galactic cosmic rays over the 11 yr solar cycle have become available. For this study, we utilize proton and helium spectra below 10 GV from these missions from 2006 to 2017 to construct a cosmic-ray transport model for a quantitative study of the processes of solar modulation. This numerical model is based on Parker’s transport equation, which includes four major transport processes. The Markov Chain Monte Carlo method is utilized to search the relevant parameter space rel

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Biermann, P. L., L. I. Caramete, A. Meli, et al. "Cosmic ray transport and anisotropies to high energies." ASTRA Proceedings 2 (October 2, 2015): 39–44. http://dx.doi.org/10.5194/ap-2-39-2015.

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Abstract. A model is introduced, in which the irregularity spectrum of the Galactic magnetic field beyond the dissipation length scale is first a Kolmogorov spectrum k-5/3 at small scales λ = 2 π/k with k the wave-number, then a saturation spectrum k-1, and finally a shock-dominated spectrum k-2 mostly in the halo/wind outside the Cosmic Ray disk. In an isotropic approximation such a model is consistent with the Interstellar Medium (ISM) data. With this model we discuss the Galactic Cosmic Ray (GCR) spectrum, as well as the extragalactic Ultra High Energy Cosmic Rays (UHECRs), their chemical a

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Sarkar, Kartick C., Santanu Mondal, Prateek Sharma, and Tsvi Piran. "Misaligned Jets from Sgr A* and the Origin of Fermi/eROSITA Bubbles." Astrophysical Journal 951, no. 1 (2023): 36. http://dx.doi.org/10.3847/1538-4357/acd75d.

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Abstract One of the leading explanations for the origin of Fermi Bubbles is past jet activity in the Galactic center supermassive black hole Sgr A*. The claimed jets are often assumed to be perpendicular to the Galactic plane. Motivated by the orientation of pc-scale nuclear stellar disk and gas streams, as well as a low inclination of the accretion disk around Sgr A* inferred by the Event Horizon Telescope, we perform hydrodynamical simulations of nuclear jets significantly tilted relative to the Galactic rotation axis. The observed axisymmetry and hemisymmetry (north–south symmetry) of Fermi

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Cagnoli, Irene, and Ivan De Mitri. "Galactic cosmic ray spectral measurements with the DAMPE space mission." EPJ Web of Conferences 319 (2025): 02002. https://doi.org/10.1051/epjconf/202531902002.

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The space-based DAMPE (DArk Matter Particle Explorer) detector has been taking data since its successful launch in December 2015. Its main scientific goals include the indirect search for dark matter signatures in the cosmic electron and gamma-ray spectra, the measurements of galactic cosmic ray fluxes from tens of GeV up to hundreds of TeV and high energy gamma ray astronomy above a few GeV. In particular, results on proton and helium, which revealed new spectral features, will be described. Ongoing analyses on light, medium, and heavy mass nuclei will be outlined, together with results on se

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Sinitsyna, Vera Yu, Vera G. Sinitsyna, and Yurii I. Stozhkov. "Red Dwarfs as Sources of Cosmic Rays." EPJ Web of Conferences 260 (2022): 11033. http://dx.doi.org/10.1051/epjconf/202226011033.

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The Pamela, Fermi, AMS-02 spectrometer experimental data cannot be explained using the diffusive models of propagation of cosmic-rays accelerated at the supernova shocks and require the existence of nearby sources of cosmic rays at the distances less than one kpc. These sources could explain the growth of the ratio of galactic positrons to electrons with an energy increase, the complex dependence of the exponent of the proton and alpha spectra on the energy, the cosmic ray anomaly component origin. We consider active dwarf stars as possible sources of galactic cosmic rays in the energy range u

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