Neutrinos from galactic sources of cosmic rays with known γ-ray spectra

The recent observations of γ-rays above TeV by H.E.S.S. are of great interest [1, 2]. They will certainly help in answering the old question of the origin of the cosmic rays till the knee [3, 4, 5, 6, 7] and at the same time they could provide us a reliable guidance for what we should expect in neutrino telescopes, at least for certain sources. This is evident for the main candidate sources of galactic cosmic rays, supernova remnants (SNR) [8, 9]. The huge kinetic energy of the gas of the SNR could be effectively converted into cosmic rays by diffusive shock acceleration [10], producing enough cosmic rays to compensate the losses from the Milky Way. When the SNR is surrounded by matter that can act as a target for cosmic rays, we would have a point source of very high-energy (VHE) gamma radiation, which seems in agreement with certain observations. Since we expect that the matter around SNR is not too dense anyway, the γ-rays are not significantly absorbed, and there is a rather direct relation between VHE γ-rays and neutrinos. More in general, we think that it is important to take advantage of the detailed observations of γ-rays whenever they exist in order to formulate definite expectations for neutrino telescopes. This is certainly true after the most recent H.E.S.S. observations, that are beginning to find VHE γ-ray spectra that deviate from power law distributions above 10 TeV or so [2]. Our recipe to calculate the neutrino fluxes is described in Sect. 2 and the application to the SNR RX J1713.7-3946 is in Sect. 3. In essence, these results are a straightforward application of standard techniques [11] (and we follow as much as possible the conventions of [4] to emphasise this fact) but we hope that they are useful in the present moment, when the high-energy gamma astronomy is flourishing and the neutrino telescopes are finally becoming a reality.