We study collective wind configurations produced by a number of massive stars, and obtain densities and expansion velocities of the stellar wind gas that is to be target, in this model, of hadronic interactions. We study the expected γ-ray emission from these regions, considering in an approximate way the effect of cosmic ray modulation. We compute secondary particle production (electrons from knock-on interactions and electrons and positrons from charged pion decay), and solve the loss

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... with ionization, synchrotron, bremsstrahlung, inverse Compton, and expansion losses. We provide examples where configurations can produce sources for GLAST satellite, and the MAGIC, HESS, or VERITAS telescopes in non-uniform ways, i.e., with or without the corresponding counterparts. We show that in all cases we studied no EGRET source is expected. Keywords γ-rays · unidentified γ-ray sources PACS 1 Single and collective stellar winds LBL, WR, O and B stars lose a significant fraction of their mass in stellar winds with terminal velocities that can easily reach V ∞ ∼ 10 3 km s −1 . With mass loss rates as high asṀ ⋆ = (10 −6 − 10 −4 ) M ⊙ yr −1 , the density at the base of the wind can reach 10 −12 g cm −3 (e.g., [1]). Such winds are permeated by significant magnetic fields, and provide a matter field dense enough as to produce hadronic γ-ray emission when pervaded by relativistic particles. A typical wind configuration ([1, 2,3]) contains an inner region in free expansion (zone I) and a much larger hot compressed wind (zone II).