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We report on the variation of electric power density linked to very low frequency (VLF) signal observed during the minimum of solar cycle 25. The detected VLF signal is emitted by the NWC radio station localized in the southern hemisphere, at 21.5∘ S and 114.2∘ E. We attempt in this work to quantify the beam as detected by the Electric Field Detector (EFD) instrument onboard CSES satellite. Geometrical key parameters have been considered to analysis the variation of the power density taking into consideration the distance between the satellite trajectory and the NWC station and its conjugate region. The beam behavior is found to be subject to significant disturbances in the conjugate region with the presence of signal modulations. Above the NWC transmitter station, the beam can be considered as a hollow cone but with irregularity dependence on the electric power density.

Ultrafast single-particle imaging with intense x-ray pulses from free-electron laser sources provides a new approach for visualizing structure and dynamics on the nanoscale. After a short introduction to the novel free-electron laser sources and methods, we highlight selected applications and discuss how ultrafast imaging flourishes from method development to early applications in physics and biology to opportunities for chemical sciences.

In this study, we report on the occurrence of solar Type III radio bursts recorded by radio and plasma wave experiment (RPWS) experiment onboard Cassini spacecraft. This instrument is designed to investigate the Saturn's plasma environment and sub-auroral radio missions. RPWS/Cassini experiment allows to measure electric field over a frequency range from 1 Hz to 16 MHz (Gurnett et al., 2004). The essential observed emission is associated to the Saturnian Kilometric Radiation (SKR) which is generated in the sub-auroral regions of the magnetosphere. The capability of this experiment leads to detect Solar Type III radio bursts recorded during the increase phase of the solar activity, i.e. January 2008 to December 2014. Hence we have found more than 300 Type III solar bursts when the distance of Cassini to the Sun was about 10 AU. Observational parameters like the time occurrence, the emission frequency and the relative intensity are considered in this analysis. Those features lead us to characterize the detection conditions and to estimate the occurrence variabilities of Type III bursts.