Correlating Cosmic-Ray Electrons and Positrons in Search of Spectral Features from Pulsars

Abstract

In recent years, the Alpha Magnetic Spectrometer (AMS) on-board the International Space Station has provided unprecedented precision measurements of the electron and positron cosmic-ray fluxes in the 0.5 GeV to 1 TeV energy range. At the lower energies cosmic-ray secondary positrons dominate the flux, while at higher energies a new type of source becomes important. If that source is energetic local pulsars, they are expected to contribute to both the cosmic-ray positron and electron fluxes. This would result in features in their respective spectra that would coincide in energy; which we search for. We first fit the individual fluxes with parametrically smooth spectra to identify the significance of such features on either the electrons or the positrons and evaluate their respective residual fluxes. We then perform a cross-correlation analysis on the residual fluxes to see if their features are related and report our results.