Gamma-ray production in young open clusters: Berk 87, Cyg OB2 and Westerlund 2

Understand

Young open clusters are likely sites of cosmic ray acceleration as indicated by recent detections of the TeV gamma-ray sources in the directions of two open clusters (Cyg OB2 and Westerlund 2) and their directional proximity to some unidentified EGRET sources.

• In fact, up to now a few different scenarios for acceleration of particles inside open clusters have been considered, i.e.
• shocks in massive star winds, pulsars and their nebulae, supernova shocks, massive compact binaries.
• Here we consider in detail the radiation processes due to both electrons and hadrons accelerated inside the open cluster.