On Accuracy of Solar Cosmic Ray Anisotropy and Intensity Deduced from NM Data

Abstract Typical fittings of solar cosmic ray variations registered by the neutron monitor (NM) network do not consider real values of proton fluxes observed by satellites. However, a sharp knee of the proton spectrum may exist in the energy range of high latitude NM's during ground level enhancements (GLE) and storm particle events. This may lead to great misinterpretation of NM data, when the CR anisotropy and absolute intensity during GLE's and Forbush decreases are studied. In a case of GLE's the knee energy, but not the geomagnetic (or atmospheric) cutoff, would determine a count rate of particular NM, i.e. an impact of lower energy part of solar proton spectrum typically is overestimated. Contrary, during Forbush effects storm particles may contribute considerably to count rate of high and middle latitudes NM's. The solar proton events July 14, 2000 and November 4, 2001 illustrate the problem

Cosmic Rays near Proxima Centauri b

Cosmic rays are an important factor of space weather determining radiation conditions near the Earth and it seems to be essential to clarify radiation conditions near extrasolar planets too. Last year a terrestrial planet candidate was discovered in an orbit around Proxima Centauri. Here we present our estimates on parameters of stellar wind from the Parker model, possible fluxes and fluencies of galactic and stellar cosmic rays based on the available data of the Proxima Centauri activity and its magnetic field. We found that galactic cosmic rays will be practically absent near Proxima b up to energies of 1 TeV due to the modulation by the stellar wind. Stellar cosmic rays may be accelerated in Proxima Centauri events, which are able to permanently maintain density of stellar cosmic rays in the astrosphere comparable to low energy cosmic ray density in the heliosphere. Maximal proton intensities in extreme Proxima events should be by 3–4 orders more than in solar events

28th International Cosmic Ray Conference 3317 Prolonged Release of 100 MeV Solar Protons in the GLE Events

Abstract The solar proton events of 1991 June 11 and 15 provide evidence that > 100 MeV protons interacting in the solar atmosphere and escaping into the interplanetary space are from the same population. Events of 1997-2002 accompanied by ground level enhancements are considered. The model of diffusion propagation assuming prolonged and multiple release of solar protons fits quite well proton intensity measured within 84-200 MeV energy band. The number of protons in the solar source is estimated for different time moments by using the propagation model. The obtained numbers of interacting protons suggest that the relevant instrument should observe prolonged γ-emission with a significant contribution from π 0 -decay in many of the considered events. Apparently a notation of local radiation belts of the Sun should be introduced

Properties of a coronal electron accelerator in an eruptive solar event

International audienc

Properties of a coronal electron accelerator in an eruptive solar event

International audienc

Properties of a coronal electron accelerator in an eruptive solar event

International audienc