Current Research Highlights

Current Research Highlights

Original 1519211826

Buoyant bubbles in galaxy clusters and heating of the intracluster medium

March 01, 2018
Buoyant bubbles of relativistic plasma in galaxy cluster cores plausibly play a key role in conveying the energy from a supermassive black hole to the intracluster medium (ICM). While the amount of energy supplied by the bubbles to the ICM is set by energy conservation, the physical mechanisms involved in coupling the bubbles and the ICM are still being debated. A team of researchers from the Max Planck Institute for Astrophysics (MPA) and the University of Oxford argues that internal waves might be efficient in extracting energy from the bubbles and distributing it over large masses of the ICM. [more]
Teaser image horizontal 1517417700

Tsunamis and Ripples: Effects of Scalar Waves on Screening in the Milky Way

February 01, 2018
Modified gravity models often contain some form of screening to reduce to general relativity in our immediate cosmic neighbourhood. Scalar waves from astrophysical or cosmological events were thought to significantly disrupt this screening of the Solar System, invalidating previously viable modified gravity models. MPA scientists show that disruptions are actually generally negligible for physically relevant setups. [more]
Teaser 1514881077

Neutron Stars on the Brink of Collapse

January 01, 2018
Neutron stars are the densest objects in the Universe; however, their exact characteristics remain unknown. Using recent observations and simulations, an international team of scientists including researchers at the Max Planck Institute for Astrophysics (MPA) has managed to narrow down the size of these stars. Thus the scientists were able to exclude a number of theoretical descriptions for the neutron star matter. [more]
Teaser image horizontal 1512070787

LOFAR radio observations document rejuvenation in space

December 01, 2017
In observations of galaxy clusters, astronomers in collaboration with the MPA discovered a new class of cosmic radio sources. With the digital radio telescope Low Frequency Array (LOFAR) they received the longest radio waves that can be measured on Earth. They identified a remarkable "tail"behind a galaxy in the radio light, which must have been re-energized after it had faded away. In the journal Science Advances, the team describes this discovery, which either confirms a theoretical prediction on the interaction between shock waves and radio plasma or represents a novel phenomenon. [more]
Right content 1508924696

Bridging the Gap: From Massive Stars to Supernovae in 3D

November 01, 2017
A team of astrophysicists from Queen’s University Belfast, the Max Planck Institute for Astrophysics (MPA), and Monash University (Australia) has, for the first time, performed three-dimensional computer simulations that follow the evolution of a massive star from its final phase of nuclear burning, through the collapse of the stellar iron core, into the first seconds of the beginning explosion as a supernova. The simulations show that the large-scale violent convective motions that stir the oxygen burning layer at the onset of collapse can provide crucial support for the explosion of the star. [more]
Teaser image vertical 1506430534

Rise and Shine: Type Ia supernova models at early times

October 01, 2017
Type Ia supernovae (SNe Ia) are spectacular explosions in white dwarf stars and play an essential role in astrophysics in general and in cosmological studies in particular. However, many puzzles about the nature and the inherent physical mechanisms in SNe Ia are still waiting to be answered. Robotic surveys of the next decade will provide an unprecedented wealth of observed Type Ia supernovae, detected shortly after explosion. Researchers at MPA examine here whether different explosion models are expected to leave clear imprints in such early observations that could be used in future photometric surveys to help shedding light on the progenitors and explosion mechanism of SNe Ia. [more]
Teaser 1503316854

Probing molecular clouds with supermassive black hole X-ray flares

September 01, 2017
The centre of the Milky Way is a very special place, harboring many exotic objects, such as the supermassive black hole Sagittarius A* and giant molecular clouds. Some of these clouds, despite being cold, are sources of high energy photons. It is believed that the clouds are not producing these photons themselves, but rather scatter the X-ray radiation coming from outside.  Even though Sgr A* is currently very faint in X-rays, it is considered as the main culprit of this radiation, in the form of short but intense flares, which happened over the past few hundred years. The time delay caused by light propagation from Sgr A* to the clouds and then to us, allows one to study Sgr A*’s past activity. At the same time, flares serve as an extremely powerful probe of molecular gas properties. In particular, the full 3D structure of molecular clouds and their density distribution on small scales can be reconstructed. [more]