Related papers: Constraining positron emission from pulsar populat…
We argue that both the positron fraction measured by PAMELA and the peculiar spectral features reported in the total electron-positron (e+e-) flux measured by ATIC have a very natural explanation in electron-positron pairs produced by…
The recent discovery of a new population of ultra-high-energy gamma-ray sources with spectra extending beyond 100 TeV revealed the presence of Galactic PeVatrons - cosmic-ray factories accelerating particles to PeV energies. These sources,…
The most numerous source class that emerged from the H.E.S.S. Galactic Plane Survey are Pulsar Wind Nebulae (PWNe). The 2013 reanalysis of this survey, undertaken after almost 10 years of observations, provides us with the most sensitive…
As the TeV halos around Geminga and PSR B0656+14 have been confirmed by HAWC, slow diffusion of cosmic rays could be general around pulsars, and the cosmic positron spectrum from pulsars could be significantly changed. As a consequence, the…
Extended $\gamma$-ray emission has been observed around several nearby pulsars and is commonly interpreted as inverse-Compton radiation produced by relativistic electrons and positrons diffusing in the surrounding interstellar medium. In…
Recent observations by PAMELA, Fermi-LAT, and AMS-02 have conclusively indicated a rise in the cosmic-ray positron fraction above 10 GeV, a feature which is impossible to mimic under the paradigm of secondary positron production with…
We study the prospects for discriminating between the dark matter (DM) and pulsar origin of the PAMELA positron excess with the Alpha Magnetic Spectrometer AMS-02. We simulate the response of AMS-02 to positrons (and electrons) originating…
Pulsar wind nebulae (PWNe) dominate the galactic gamma-ray sky at very high energies and they are major contributors to the leptonic cosmic ray flux. However, the question of whether or not pulsars also accelerate ions to comparable…
Pulsar wind nebulae (PWNe) constitute the largest population of Galactic very-high-energy (VHE; $E > 100$ GeV) $\gamma$-ray sources and are key laboratories for studying particle acceleration and pulsar--supernova remnant (SNR)…
This thesis presents an analysis of the cosmic-ray electron and positron flux using the AMS-02 detector on the International Space Station as a function of time and energy. The time-averaged flux is integrated over 6.5 years of AMS-02…
It has long been suggested that nearby pulsars within $\sim 1 \,{\rm kpc}$ are the leading candidate of the 10-500 GeV cosmic-ray positron excess measured by PAMELA and other experiments. The recent measurement of surface brightness profile…
Several cosmic ray experiments have measured the positron fraction up to few hundred GeV. Their data have revealed an excess of positrons above 10 GeV that is not consistent with the secondary production of these particles in the…
We present an analysis of the extended emission around the anomalous X-ray pulsar 1E 1547.0-5408 using four XMM-Newton observations taken with the source in varying states of outburst as well as in quiescence. We find that the extended…
The recently detected gamma-ray emission from Starburst galaxies is most commonly considered to be diffuse emission arising from strong interactions of accelerated cosmic rays. Mannheim et al. (2012), however, have argued that a population…
The AMS-02 has just published the unprecedentedly precise measurement of the cosmic electron and positron spectra. In this paper we try to give a quantitative study on the AMS-02 results by a global fitting to the electron and positron…
Pulsars are highly magnetized rotating neutron stars, emitting in a broad electromagnetic energy range. Reproducing the observed pulsars population refines our understanding of their formation and evolution scenarios as well as their…
Very-high-energy $\gamma$-ray emission provides constraints on the morphology and the physics mechanisms involved in the evolution of pulsar wind nebulae (PWNe). In the Galactic plane, around $312 ^{\circ}$ of Galactic longitude, a…
We present novel constraints on cosmic-ray propagation in the Galaxy using the recent precise measurements of proton and helium spectra from AMS-02, together with preliminary AMS-02 data on the antiproton over proton ratio. To explore…
We present a precise measurement of the combined electron plus positron flux from 0.5 GeV to 1 TeV, based on the analysis of the data collected by the Alpha Magnetic Spectrometer during the first 30 months of operations aboard the…
A measurement of the cosmic ray positron fraction e+/(e+ + e-) in the energy range of 1-30 GeV is presented. The measurement is based on data taken by the AMS-01 experiment during its 10 day Space Shuttle flight in June 1998. A proton…