Speaker
Description
Determination of sources and acceleration mechanisms of ultra high energy cosmic rays (UHECRs) is one of the major unsolved problems in modern astrophysics. Powerful shock waves that take place in several types of potential Galactic sources, such as Supernova Remnants (SNRs), Star formation regions, and Pulsar wind nebulae (PWNe), can provide an effective diffusive shock acceleration of protons, heavier nuclei, and electrons/positrons. The non-thermal high-energy (HE) and very high-energy (VHE) gamma-ray emission from these sources should be a promising manifestation of acceleration processes. In this work we have investigated the possibility to explain HE and VHE gamma-ray emission from the sky region of the magnetar SGR1900+14, as a signature of accelerated CRs. We have simulated gamma-ray emission from the extended Fermi-LAT source 4FGL J1908.6+0915e, as well as from the extended VHE H.E.S.S. source candidate HOTS J1907+091, and the point-like HAWC TeV source 3HWC J1907+085, which are spatially coincident with the magnetar SGR 1900+14 , the SNR G42.8+0.6, and the star forming region W49A. Our simulations took into account hadronic and leptonic models of gamma-ray emission. The most promising models for source evolution are magnetar-connected but still undetected SNR and PWN, but with a strong requirement for the energy reserve of emitted CR particles. This energy requirement can be provided by the magnetar-related Hypernova and/or magnetar wind nebula remnant created by the newborn millisecond magnetar with a large supply of rotational energy.
