Non‐thermal X‐rays and very high energy (VHE) γ‐rays have been detected from the supernova remnant (SNR) RX J1713.7−3946, and the recent observations with the Suzaku satellite clearly reveal a spectral cut‐off in the X‐ray spectrum, which directly relates to the cut‐off of the energy spectrum of the parent electrons. However, whether the origin of the VHE γ‐rays from the SNR is hadronic or leptonic is still in debate. We studied the multi‐band non‐thermal emission from RX J1713.7−3946 based on a semi‐analytical approach towards the non‐linear shock acceleration process by including the contribution of the accelerated electrons to the non‐thermal radiation. The results show that the multi‐band observations on RX J1713.7−3946 can be well explained in the model with appropriate parameters, and the TeV γ‐rays have hadronic origin, i.e. they are produced via proton–proton interactions as the relativistic protons accelerated by the shock collide with the ambient matter.

In this paper we study the high-energy neutrino emission from low-mass microquasars (LMMQs) by assuming that an acceleration region for particles is located in the inner jet, based on the framework of a hadronic jet model. Adopting the parametrized formulae for inelastic pp interactions and the recent pγ parametrizations, we calculate the spectral energy distributions (SEDs) of various photon and neutrino spectra. Furthermore, we also consider the electromagnetic cascade processes due to γ γ absorption. We then apply the jet model to the microquasar (MQ) GX 339-4, and calculate the expected neutrino event rate for three years of observations using the newest effective area of the KM3NeT detector in the Mediterranean Sea. The resulting results indicate that (1) photon spectra can roughly reproduce observations from radio to X-ray energies, and can also predict emission fluxes at high and very high energies (VHE); (2) GX 339-4 is a potential neutrino source, neutrinos from which are likely to be identified with some years of observations from the next-generation km 3 -scale neutrino telescopes.

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The bright TeV source HESS J1640-465 is positionally coincident with the young supernova remnant (SNR) G338.3-0.0, and the nearby HESS J1641-463 with TeV gamma-ray emission seems to be closely associated with it. Based on the nonlinear diffusion shock acceleration model, we explore the emission from these two TeV sources, the particle diffusion is assumed to be different inside and outside the absorbing boundary of the particles accelerated in the SNR shock. The results indicate that (1) the GeV-TeV emission from the region of the HESS J1640-465 is produced as a result of the particle acceleration inside the SNR G338.3-0.0 and (2) the runaway cosmic-ray particles outside the SNR are interacting with the nearby dense molecular cloud (MC) at the region of the HESS J1641-463, corresponding π 0 decay gamma-ray in proton-proton collision contribute to the TeV emission from the HESS J1641-463. Also, we investigate the possible X-ray emission in MC from the synchrotron procedure by secondary e ± produced through escaped protons interaction with the MC.

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