Related papers: Solar and Galactic Cosmic Rays observed by SOHO
We present a comparison between low and high energy solar energetic protons (SEPs) as observed by the SOHO/ERNE high energy detector in solar cycle (SC) 23. Observed and corrected peak proton intensities are used in the analyses. The linear…
Our direct knowledge of solar eruptive events is limited to several decades and does not include extreme events, which can only be studied by the indirect proxy method over millennia, or by a large number of sun-like stars. There is a gap,…
An extinction-free estimator of the star-formation rate (SFR) of galaxies is critical for understanding the high-redshift universe. To this end, the nearly linear, tight correlation of far-infrared (FIR) and radio luminosity of star-forming…
Gradual solar energetic particle (SEP) events are generally attributed to the particle acceleration in shock waves driven by coronal mass ejections (CMEs). Space-weather effects of such events are important, so there has been continuous…
The main sources of solar energetic particle (SEP) events are solar flares and shocks driven by coronal mass ejections (CMEs). While it is generally accepted that energetic protons can be accelerated by shocks, whether or not these shocks…
In order to discuss the potential impact of solar 'superflares' on space weather, we investigated statistical relations among energetic proton peak flux with energy higher than $ 10 \rm MeV$ ($F_p$), CME speed near the Sun ($V_{CME}$)…
Solar Energetic Particles (SEPs) are an important component of Space Weather, including radiation hazard to humans and electronic equipment, and the ionisation of the Earth's atmosphere. We review the key observations of SEPs, our current…
We study changes of the galactic cosmic ray (GCR) intensity for the ending period of the solar cycle 23 and the beginning of the solar cycle 24 using neutron monitors experimental data. We show that an increase of the GCR intensity in 2009…
The most powerful explosions on the Sun [...] drive the most severe space-weather storms. Proxy records of flare energies based on SEPs in principle may offer the longest time base to study infrequent large events. We conclude that one…
This paper reports on the observation of the sidereal large-scale anisotropy of cosmic rays using data collected by the ARGO-YBJ experiment over 5 years (2008$-$2012). This analysis extends previous work limited to the period from 2008…
Solar energetic particle (SEP) events are a prime opportunity to probe astrophysical particle acceleration by combining in-situ measurements of particles in space with remote sensing of the hard X-ray (HXR) and \gamma-ray emitting particles…
The Solar and Heliospheric Observatory (SOHO) Extreme-ultraviolet Imaging Telescope (EIT) has been taking images of the Solar disk and corona in four narrow EUV bandpasses (171\AA, 195\AA, 284\AA, and 304\AA) at a minimum cadence of once…
Modulation of galactic cosmic ray intensity is governed by several mechanisms including diffusion, convection, adiabatic energy losses and drift. Relative roles of these factors change in the course of an 11-year solar cycle. That can…
We have developed an interactive program which shows the solar energetic particle (SEP) intensity-time profile as observed by SOHO/ERNE, simultaneously with the associated coronal mass ejection in optical imaging movies taken by LASCO…
We compare the characteristics of flare-accelerated energetic electrons at the Sun with those injected into interplanetary space. We have identified 17 energetic electron events well-observed with the SEPT instrument aboard STEREO which…
We have studied long-term variations of galactic cosmic ray (GCR) intensity in relation to the sunspot number (SSN) during the most recent solar cycles. This study analyses the time-lag between the GCR intensity and SSN, and hysteresis…
Solar flares (SFs) are sudden brightening observed over the Sun surface which is associated with a large energy release. Flares with burst of Xray emission are normally followed by a mass ejection of electrons and ions from the solar…
We discuss two extraordinary increases of cosmic ray intensity observed by Voyager 1 in the last 1.1 AU before heliopause crossing, Aug 2012 at 121.7 AU. The two increases are roughly similar in amplitude and result in a total increase of…
Large solar flares and eruptions may influence remote regions through perturbations in the outer-atmospheric magnetic field, leading to causally related events outside of the primary or triggering eruptions that are referred to as…
Context: The HELIOS solar observation probes provide unique data regarding their orbit and operation time. One of the onboard instruments, the Experiment 6 (E6), is capable of measuring ions from 4 to several hundred MeV/nuc. Aims: In this…