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Recent observations show that the cosmic ray nuclei spectra start to harden above 100 GeV, in contradiction with the conventional steady-state cosmic ray model. We had suggested that this anomaly is due to the propagation effect of cosmic…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Wei Liu , Pierre Salati , Xuelei Chen

The AMS Collaboration has recently released data on cosmic ray (CR) leptons and hadrons that can shed light on two exciting problems in CR physics: on one side, the origin of the rise of the CR positron fraction above ~10 GeV of energy, on…

High Energy Astrophysical Phenomena · Physics 2015-11-02 Nicola Tomassetti

Recent data on Galactic cosmic-ray (CR) leptons and hadrons gave rise to two exciting problems: on the lepton side, the origin of the rise of the CR positron fraction e+/(e- + e+) at ~10 - 300 GeV of energy; on the hadron side, the nature…

High Energy Astrophysical Phenomena · Physics 2015-04-16 N. Tomassetti , F. Donato

Recent balloon-borne and satellite experiments have established new features in the behavior of the spectra of cosmic rays. An analysis of all the data showed that hardening of most abundant primary cosmic ray nuclei spectra with increasing…

High Energy Astrophysical Phenomena · Physics 2019-05-17 A A Lagutin , N V Volkov , R I Raikin , A G Tyumentsev

Cosmic-ray proton and helium spectra have been measured with the balloon-borne Cosmic Ray Energetics And Mass experiment flown for 42 days in Antarctica in the 2004-2005 austral summer season. High-energy cosmic-ray data were collected at…

The AMS-02 experiment has reported precise measurements of energy spectra of several cosmic-ray species in the range of ~(0.5-2000) GeV/n. An intriguing finding is the differences in the spectral shape between the different species. Protons…

High Energy Astrophysical Phenomena · Physics 2021-07-28 Satyendra Thoudam , Björn Eichmann , Jörg P. Rachen

The observed spectrum of Galactic cosmic rays has several exciting features such as the rise in the positron fraction above ~10 GeV of energy and the spectral hardening of protons and helium at ~300 GeV/nucleon of energy. The ATIC-2…

High Energy Astrophysical Phenomena · Physics 2015-09-22 Nicola Tomassetti

The precision measurements of the spectra of cosmic ray nuclei and leptons in recent years have revealed the existence of multiple features, such as the spectral break at $\sim 300$ GV rigidity seen by PAMELA and AMS-02 and more recently…

High Energy Astrophysical Phenomena · Physics 2022-01-05 Carmelo Evoli , Elena Amato , Pasquale Blasi , Roberto Aloisio

A hardening of the proton and helium fluxes is observed above a few hundreds of GeV/nuc. The distribution of local sources of primary cosmic rays has been suggested as a potential solution to this puzzling behavior. Some authors even claim…

High Energy Astrophysical Phenomena · Physics 2017-04-05 P. Salati , Y. Génolini , P. Serpico , R. Taillet

Recent measurements of cosmic rays by various experiments have found that the energy spectrum of cosmic rays is harder in the TeV region than at GeV energies. The origin of the spectral hardening is not clearly understood. In this paper, we…

High Energy Astrophysical Phenomena · Physics 2015-09-02 Satyendra Thoudam , Jörg Hörandel

An analysis is made of the fine structure in the cosmic ray energy spectrum: new facets of present observations and their interpretation and the next step. It is argued that less than about 10% of the intensity of the helium `peak' at the…

High Energy Astrophysical Phenomena · Physics 2011-11-15 A. D. Erlykin , A. W. Wolfendale

High precision spectrometry of galactic cosmic rays (CR) has revealed the lack of our understanding of how different CR elements are extracted from the supernova environments to be further accelerated in their shocks. Comparing the spectra…

High Energy Astrophysical Phenomena · Physics 2017-07-11 Adrian Hanusch , Tatyana Liseykina , Mikhail Malkov

Primary cosmic-ray elemental spectra have been measured with the balloon-borne Cosmic Ray Energetics And Mass (CREAM) experiment since 2004. The third CREAM payload (CREAM-III) flew for 29 days during the 2007-2008 Antarctic season.…

The recent observations revealed that the cosmic-ray (CR) proton spectrum showed a complex structure: the hardening at $\rm \sim 200~GeV$ and softening at $\rm \sim 10~TeV$. However, so far the physical origins of this spectral feature…

High Energy Astrophysical Phenomena · Physics 2023-07-26 Lin Nie , Yang Liu , Zejun Jiang

Recent measurements of cosmic ray proton and helium spectra show a hardening above a few hundreds of GeV. This excess is hard to understand in the framework of the conventional models of Galactic cosmic ray production and propagation. We…

High Energy Astrophysical Phenomena · Physics 2013-10-01 Guilhem Bernard , Timur Delahaye , Yong-Yeon Keum , Wei Liu , Pierre Salati , Richard Taillet

The unprecedented quality of the data collected by the AMS-02 experiment onboard the International Space Station allowed us to address subtle questions concerning the origin and propagation of cosmic rays. Here we discuss the implications…

High Energy Astrophysical Phenomena · Physics 2019-06-05 Carmelo Evoli , Roberto Aloisio , Pasquale Blasi

Recent precision measurements of the flux of cosmic ray positrons by the Alpha Magnetic Spectrometer show that the spectrum has a marked softening feature for energies close to one TeV. A possible interpretation of this result is that the…

High Energy Astrophysical Phenomena · Physics 2019-02-19 Paolo Lipari

Many experiments have confirmed the spectral hardening in a few hundred GV of cosmic ray (CR) nuclei spectra, and 3 different origins have been proposed: the primary source acceleration, the propagation, and the superposition of different…

High Energy Astrophysical Phenomena · Physics 2021-03-23 Jia-Shu Niu

The galactic cosmic rays (GCR) suffer from solar modulation when they propagate through the heliosphere. The transfer of the local interstellar spectrum (LIS) to the top-of-atmosphere spectra (TOA) is influenced by solar wind convection,…

High Energy Astrophysical Phenomena · Physics 2024-12-10 Cheng-Rui Zhu