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Related papers: Looking for a charge asymmetry in cosmic rays

200 papers

We use a wide range of observations to constrain cosmological models possessing a significant asymmetry in the lepton sector, which offer perhaps the best chance of reconciling a critical-density Universe with current observations. The…

Astrophysics · Physics 2009-11-06 Julien Lesgourgues , Andrew R. Liddle

The Fermi Large Area Telescope (LAT) has provided the measurement of the high energy cosmic ray electrons plus positrons (CRE) spectrum with unprecedented accuracy form 20 GeV to 1 TeV. Recently this range has been extended down to ~ 7 GeV.…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Giuseppe Di Bernardo , Daniele Gaggero , Dario Grasso

The data collected by ATIC, CREAM and PAMELA all display remarkable cosmic-ray-nuclei spectrum hardening above the magnetic rigidity $\sim$ 240 GV. One natural speculation is that the primary electron spectrum also gets hardened (possibly…

High Energy Astrophysical Phenomena · Physics 2013-12-24 Lei Feng , Rui-Zhi Yang , Hao-Ning He , Tie-Kuang Dong , Yi-Zhong Fan , Jin Chang

In this work, we revisit the all-sky Galactic diffuse $\gamma$-ray emission taking into account the new measurements of cosmic ray electron/positron spectrum by PAMELA, ATIC and Fermi, which show excesses of cosmic electrons/positrons…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Juan Zhang , Qiang Yuan , Xiao-Jun Bi

We extract the positron and electron fluxes in the energy range 10 - 100 GeV by combining the recent data from PAMELA and Fermi LAT. The {\it absolute positron and electron} fluxes thus obtained are found to obey the power laws: $E^{-2.65}$…

High Energy Physics - Phenomenology · Physics 2009-11-19 C. Balázs , N. Sahu , A. Mazumdar

The DAMPE experiment has recently reported an electron spectrum that can be explained by dark matter annihilation into charged lepton pairs in a nearby dark matter clump. The accompanying bremsstrahlung may yield a gamma-ray excess with a…

High Energy Astrophysical Phenomena · Physics 2018-08-20 Tathagata Ghosh , Jason Kumar , Danny Marfatia , Pearl Sandick

Recent results from the PAMELA experiment indicate an excess in the positron spectrum above 10 GeV, but anti-proton data are consistent with the expected astrophysical backgrounds. We propose a scenario that reproduces these features. Dark…

High Energy Physics - Phenomenology · Physics 2009-09-24 Daniel J. Phalen , Aaron Pierce , Neal Weiner

It is well known that the dark matter dominates the dynamics of galaxies and clusters of galaxies. Its constituents remain a mystery despite an assiduous search for them over the past three decades. Recent results from the satellite-based…

High Energy Astrophysical Phenomena · Physics 2011-06-07 Debtosh Chowdhury , Chanda J. Jog , Sudhir K Vempati

The Fermi-LAT experiment recently reported high precision measurements of the spectrum of cosmic-ray electrons-plus-positrons (CRE) between 20 GeV and 1 TeV. The spectrum shows no prominent spectral features, and is significantly harder…

There is convincing observational evidence for an increasing cosmic-ray positron-to-electron ratio at energies larger than $\sim 10$~GeV, at odds with expectations from secondary positron production. The most recent AMS-02 data exhibit an…

High Energy Physics - Phenomenology · Physics 2019-03-21 Stefano Profumo , Farinaldo Queiroz , Clarissa Siqueira

The Large Area Telescope onboard the Fermi Gamma-ray Space Telescope has collected the largest ever sample of high-energy cosmic-ray electron and positron events. Possible features in their energy spectrum could be a signature of the…

High Energy Astrophysical Phenomena · Physics 2018-07-13 M. N. Mazziotta , F. Costanza , A. Cuoco , F. Gargano , F. Loparco , S. Zimmer

We discuss challenges to a dark matter annihilation interpretation of the excess positron fraction in the cosmic rays observed by the PAMELA, Fermi-LAT and AMS-02 collaborations. The spectra of positrons from annihilations into the leptonic…

High Energy Physics - Phenomenology · Physics 2013-12-31 Vassilis C. Spanos

Recent measurements of cosmic ray electrons and positrons by PAMELA, ATIC, Fermi and HESS have revealed interesting excesses and features in the GeV-TeV range. Many possible explanations have been suggested, invoking one or more nearby…

High Energy Astrophysical Phenomena · Physics 2010-02-01 Pierre Brun , Gianfranco Bertone , Marco Cirelli , Emmanuel Moulin , Jean-Francois Glicenstein , Fabio Iocco , Lidia Pieri

The Alpha Magnetic Spectrometer (AMS-02) has provided unprecedented precision measurements of the electron and positron cosmic-ray fluxes and the positron fraction spectrum. At the higher energies, sources as energetic local pulsars, may…

High Energy Astrophysical Phenomena · Physics 2023-03-15 Ilias Cholis , Thressay Hoover

The decay of dark matter is predicted by many theoretical models and can produce observable contributions to the cosmic-ray fluxes. I shortly discuss the interpretation of the positron and electron excess as observed by PAMELA and Fermi LAT…

High Energy Physics - Phenomenology · Physics 2009-10-30 Christoph Weniger

The Alpha Magnetic Spectrometer (AMS-02), which is scheduled to be deployed onboard the International Space Station later this year, will be capable of measuring the composition and spectra of GeV-TeV cosmic rays with unprecedented…

High Energy Astrophysical Phenomena · Physics 2014-11-20 Miguel Pato , Dan Hooper , Melanie Simet

We introduce new sum rules allowing to determine universal properties of the unknown component of the cosmic rays and show how they can be used to predict the positron fraction at energies not yet explored by current experiments and to…

High Energy Physics - Phenomenology · Physics 2015-03-17 Mads T. Frandsen , Isabella Masina , Francesco Sannino

Cosmic-ray positrons have long been considered a powerful probe of dark matter annihilation. In particular, myriad studies of the unexpected rise in the positron fraction have debated its dark matter or pulsar origins. In this paper, we…

High Energy Astrophysical Phenomena · Physics 2022-01-07 Isabelle John , Tim Linden

We show that the positron excess measured by the PAMELA experiment in the region between 10 and 100 GeV may well be a natural consequence of the standard scenario for the origin of Galactic cosmic rays. The 'excess' arises because of…

High Energy Astrophysical Phenomena · Physics 2009-09-02 Pasquale Blasi