When a high-energy cosmic-ray particle enters the upper layer of the atmosphere, it generates many secondary high-energy particles and forms a cosmic-ray-induced air shower. In the leading plasma of this shower electric currents are induced that emit electromagnetic radiation. These radio waves can be detected with LOw-Frequency ARray (LOFAR) radio telescope. Events have been collected under...
Nowadays there is compelling evidence for the existence of dark matter in the Universe. A general consensus has been expressed on the need for a directional sensitive detector to confirm, with a complementary approach, the candidates found in “conventional” searches and to finally extend their sensitivity beyond the limit of neutrino-induced background. We propose here the use of a detector...
LORA (LOFAR Radboud Air shower array) is a particle detector build around the LOFAR core to complement radio detection of cosmic rays. The LORA instrument has been critical in determining the arrival direction, energy, and core location of cosmic rays detected with LOFAR. LORA detects particles from a cosmic ray induced extensive air shower and triggers the LOFAR antennas to read out relevant...
The initial and yet fundamental process in a typical cloud-to-ground lightning strike includes the
propagation of a very faint and charged channel which is called stepped leader. The exact
mechanism for the step leaders is not understood. The reason for this is that the temporal and/or
spatial resolution of the devices exploited for observing this phenomenon has not been sufficient.
The...
We present a bottom-up and a top-down model that can produce high-energy neutrinos.
Gamma rays bursts (GRBs) are flashes of gamma rays which are associated with extremely high energetic explosions in distant galaxies. The relativistic fireball is the most popular model to explain the GRBs. Within the fireball model ultra-high energetic cosmic rays can be produced. It is also likely that...
Extensive air showers are an interesting phenomena because they can provide information about, among many other things, the electric fields present in the atmosphere, an understanding of which is necessary to understand the concept of lightning.
To be able to deduce the electric fields from the radio footprint we have developed a macroscopic code that uses a parametrized shower profile. We...
