Cosmic ray positrons from a local, middle-aged supernova remnant

Understand

We argue that the cosmic ray positron excess observed in ATIC-2, Fermi LAT, PAMELA, HESS and recently in the precision AMS-02 experiment can be attributed to the production in a local, middle-aged supernova remnant (SNR).

• Using the prediction of our model of cosmic ray acceleration in SNR we estimate that the SNR responsible for the observed positron excess is located between 250 and 320pc from the Sun and is 170-380 kyear old.
• The most probable candidate for such a source is the SNR which gave birth to the well-known Geminga pulsar, but is no longer visible.
• Other contenders are also discussed.