Search
Nederlands
FNWI --- IMAPP Department of Astrophysics
Radboud University > Faculty of Science > Department of Astrophysics > Research > Radio Astronomy and Astroparticle Physics research

Radio Astronomy and Astroparticle Physics research

An overview of research topics in the area of Radio Astronomy and Astroparticle Physics:

Ultra-High-Energy Cosmic Rays

Pierre Auger Observatory

The highest-energy particles in the Universe are cosmic rays (ionized nuclei) with energies exceeding 1020 eV. The origin of these particles continues to be one of the biggest mysteries and is investigated with the Pierre Auger Observatory. Read more...

AERA - Radio detection of cosmic rays at the Auger Observatory

Radio emission from extensive air showers is measured with the Auger engineering Radio Array (AERA). Radio detection of ultra-high energy cosmic rays is a novel technique that may help to unravel the secrets of these enigmatic particles. Read more...

Radio detection of cosmic-ray particles with LOFAR

The LOFAR key science project “cosmic rays” focuses on the detection of radio emission induced by high-energy particles from the universe. In one part of the project we use the earth's atmosphere as a detector. High-energy cosmic rays collide with air molecules, induce extensive air showers, and produce radio flashes that last only nanoseconds, yet can be detected with LOFAR. Read more ...

NuMoon - using the moon as cosmic particle detector

Moon (NASA) In another part of the LOFAR key science project “cosmic rays” we use the entire moon as a detector. Ultra high-energy neutrinos and (charged) cosmic rays, impinging on the surface of the Moon produce radio Cherenkov radiation, which we could detect from earth. This provides the best information on the flux of cosmic particles at the very highest particle energies ever probed. Read more...

LORA - The LOFAR-Radboud Airshower array

A small air shower array has been installed in the core of LOFAR, the LOFAR Radboud Air Shower Array (LORA). The objective is to measure basic properties of air showers and to provide a trigger signal for the radio antennas of LOFAR. Read more ...

LOPES - The LOFAR Prototype Station for radio-detection of cosmic rays

The measurements of radio emission from extensive air showers have been pioneered with the LOPES experiment, which continues to be a valuable asset. Read more...

TRACER - Transition Radiation Array for Cosmic Energetic Radiation (balloon experiment)

TRACER is a balloon-borne particle detector to measure cosmic radiation. With TRACER we study the propagation of cosmic-ray nuclei through our Galaxy.
Read more...


Black Holes and Jets

LOFAR imaging survey

One of the main goals of the LOFAR radio telescope is to map the sky. Just like maps of the earth help us to navigate our planet, the result of the LOFAR imaging survey will help us to understand better the evolution and content of our universe. The maps made by LOFAR will be of unprecedented high-resolution and depth at the low radio frequency that the survey is probing. New discoveries await. Read more...

Jets and Lobes

In the radio regime one often observes collimated outflows that originate in the center of a galaxy and terminate in giant lobes outside the optical galaxy itself. It has been established that these so called jets are launched by the supermassive black holes in the centers of the galaxies. These black holes are accreting their surrounding gas and part of that energy is injected into these collimated outflows. What causes these jets and how do they interact with their environment? Read more...

Event Horizon

Black Holes are the most extreme objects in our universe, tilting space time to its utmost. Their defining characteristic is the `event horizon’ – a one-way membrane, separating the inside from the outside. What goes in, never comes back – not even light can escape its grip. Will we ever be able to see this enigmatic region in space with our telescopes? Well, we may … Read more...

Fundamental Plane & BH Unification

Supermassive black holes are thought to exist in the centers of galaxies. If the black hole accretes matter, it can be observed as an active galactic nuclus (AGN). Black holes do not only exist as supermassive black holes (millions of solar masses), they are also found in stellar X-ray binaries (XRBs), which harbor black holes of the order of 10 solar masses. The central engine of both types consists of the black holes, an accretion disc surrounded by a corona and a relativistic jet. It has recently been found that the central engine of all accreting objects is essentially scale invariant; the basic ingredients, especially the interplay between the accretion disc and the jet are similar in all cases. This scale invariance has been shown using a number of empirical correlations. Read more...

Radiation Processes

(Image courtesy Argonne National Laboratory and Idaho National Laboratory)To handle complex radiating systems in a logical fashion, we have developed the “end-point” methodology, by which radiation is calculated from an instantaneous particle acceleration/deceleration event. Read more...

MHD Simulations

Charles Gammie: 3D GRMHD simulation of black hole in the Galactic center To better understand how black holes sometimes form jets, we perform computer simulations of how inflowing gas behaves in the region closest to a black hole. These simulations use MHD (magnetohydrodynamics) and so take into account magnetic fields as well as standard hydrodynamics. Because spacetime is strongly curved close to a black hole, the effects of general relativity on the flowing gas need to be simulated as well. The output of these simulations can then be used to infer information about the path the gas takes, such as what fraction of the infalling matter ends up in the jet, and how the gas in the jet gets accelerated away from the black hole. Read more...


Radio Transients

FRATS - Searching for Fast Radio Transients

A giant pulse from the Crab PulsarFRATS stands for Fast Radio Transients. In this project we use the LOFAR radio telescope to search for pulses of a few milliseconds which can originate from neutron stars, but also from normal stars or even exo-planets. Our aim is to detect new objects and learn more about the emission mechanism of these object. Read more...

SETI – Search for Extraterrestrial Intelligence

Extrasolar PlanetsAre we alone in the universe, or are there other civilizations? What once used to be part of science fiction has now become a serious science question. The new LOFAR telescope may be an unexpected but perhaps powerful tool to help search for signatures of intelligent life on planets around distant stars. Read more...


Instrumentation

LOFAR - The Low-Frequency Array

LOFAR - Eyes of the Earth posterLOFAR is a revolutionary new digital radio telescope and the largest of its kind. It is located in the Netherlands and spreads throughout Europe. It targets the early phase of the universe as well as the most energetic cosmic particles. Read more...

SKA - Square Kilometre Array

SKAThe Square Kilometre Array (SKA) is going to be the world’s largest radio telescope, prepared by a global consortium. Already the first phase will be five times larger than LOFAR in a similar frequency range. Read more...

Lunar Radio Astronomy Explorer

Lunar Radio Astronomy ExplorerWe are actively involved in studies for lunar exploration, in particular in the development of a lunar low-frequency radio telescope. As part of the Lunar Radio Astronomy Explorer (LRX) project a prototype antenna has been implemented and simulated for the moon environment. Read more...