A 'Positron Excess' in cosmic emissions from deep space have recently been logged by various observation satellites ( PAMELA, Fermi-LAT and AMS-02 ).

As yet, there is no agreed explanation for the source of the positrons (i.e. 'anti' electrons ) in the numbers in which they are found.

There are (at least ) three current theories - some of which are contradictory. See: [ all papers are from arXiv ]

HAWC Observations Strongly Favor Pulsar Interpretations of the Cosmic-Ray Positron Excess
Supersymmetric Resonant Dark Matter: a Thermal Model for the AMS-02 Positron Excess
AMS-02 Positron Excess and Indirect Detection of Three-body Decaying Dark Matter

Also see: Cosmic raysplugin-autotooltip__plain plugin-autotooltip_bigCosmic rays

"Cosmic rays are typically protons or atomic nuclei of elements such as helium, carbon, or iron. The most energetic have energies more than 10 million times greater than those in the world’s most powerful atom smasher, the Large Hadron Collider.