Pulsar interpretation of lepton spectra measured by AMS-02

Alpha Magnetic Spectrometer (AMS-02) recently published its lepton spectra measurement. The results show that the positron fraction no longer increases above ∼ 200 GeV. The aim of this work is to investigate the possibility that the excess of positron fraction is due to pulsars. Nearby known pulsars from the ATNF catalog are considered to be a possible primary positron source of the high energy positrons. We find that the pulsars with age T ≃ ( 0.45 - 4.5 ) × 10 5 year and distance d < 0.5 kpc can explain the behavior of positron fraction of AMS-02 in the range of high energy. We show that each of the four pulsars—Geminga, J1741-2054, Monogem, and J0942-5552—is able to be a single source satisfying all considered physical requirements. We also discuss the possibility that these high energy e ± are from multiple pulsars. The multiple pulsar contribution predicts a positron fraction with some structures at higher energies.