Hunting for Dark matter in the Smallest galaxys of the Universe

Astrophysicists from the University of Surrey and the University of Edinburgh have developed a new method to measure the amount of dark matter in the center of small galaxies <x0juge”.

Dark matter makes up most of the measure of the Universe, however, remains elusive. Depending on its properties, it may be heavily concentrated in galaxies. Comparing the distribution of dark matter in galaxies with detailed patterns, researchers can test or exclude various candidates of dark matter.

The strictest restrictions on dark matter come from the smallest galaxies in the Universe, <x0-galactics, dwarf”. The smallest of them contains only a few thousand or tens of thousands of stars, the so-called dwarfs “

Such small galaxies, found around orbit near the Milky Way, consist almost entirely of dark matter. If the distribution of dark matter in these tiny galaxies can be determined, it can provide new information on its nature. However, being completely free of gas and containing very few stars until recently, there was no practical method for measuring it.

In a study published by the Monthly Notics of the Royal Astronomical Society (MNRAS), a team of scientists from the University of Surrey have developed a new method of calculating the dark inner density of dwarf galaxies, even if they do not have gas and very few stars. The key to the method is to use one or more dense clusters of stars orbiting near the center of the dwarf galaxy, Kosovo Preess broadcast.

The team uses a large suite of computer simulations to show how the structure of star groupings is sensitive to the fact that dark matter is dense in the center of galaxies or is distributed more normally. The team then applied their method to the dwarf galaxy Eridanus II, finding far less dark matter in its centre than many models would have predicted.

We've developed a new tool to discover the nature of the dark matter and the results are already exciting. Eridanus II, one of the smallest known galaxies, if there are similar results for a greater sample of galaxies, this may have broad implications for the nature of dark matter “, said Philippo Canteta from the University of Surrey and the chief author of the study.

While Mark Gieles, professor of Astrophysics at the University of Surrey and chief investigator of the European Research Council (ERC) project's project funding, said they have begun the project in hopes they can use cluster of stars to learn about dark matter.

Professor Justin Read, a coauthor of the study by the University of Surrey, said it is difficult to understand the results for Eridaus II, if the dark material contains a cool “particle that interacts: the current model favoured for dark matter.

The possibility is that the dark matter in the center of Eridanus II was the hot “” from the violent formation of the stars, as suggested by some recent numeric models”, he said.

While Jorge Penarrubia from the University of Edinburgh School of Fisica and Astronomy says the findings provide interesting knowledge of the distribution of dark matter in galaxies in the Universe.