Ensemble Fluctuations of the Flux and Nuclear Composition of Ultra-High Energy Cosmic Ray Nuclei

Understand

The flux and nuclear composition of ultra-high energy cosmic rays depend on the cosmic distribution of their sources.

• Data from cosmic ray observatories are yet inconclusive about their exact location or distribution, but provide a measure for the average local density of these emitters.
• Due to the discreteness of the emitters the flux and nuclear composition is expected to show ensemble fluctuations on top of the statistical variations, i.e.
• "cosmic variance".