Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Dead galaxies in Coma Cluster may be packed with dark matter

20.07.2015

Galaxies in a cluster roughly 300 million light years from Earth could contain as much as 100 times more dark matter than visible matter, according to an Australian study.

The research, published today, used powerful computer simulations to study galaxies that have fallen into the Coma Cluster, one of the largest structures in the Universe in which thousands of galaxies are bound together by gravity.


This artist's impression of the 'quenching' process shows how a normal blue (star-forming) galaxy lost its gas while falling into the Coma Cluster very early on in its formation.

Credit: Cameron Yozin, ICRAR/UWA

"It found the galaxies could have fallen into the cluster as early as seven billion years ago, which, if our current theories of galaxies evolution are correct, suggests they must have lots of dark matter protecting the visible matter from being ripped apart by the cluster."

Dark matter cannot be seen directly but the mysterious substance is thought to make up about 84 per cent of the matter in the Universe.

International Centre for Radio Astronomy Research PhD student Cameron Yozin, who led the study, says the paper demonstrates for the first time that some galaxies that have fallen into the cluster could plausibly have as much as 100 times more dark matter than visible matter.

Yozin, who is based at The University of Western Australia, says the galaxies he studied in the Coma Cluster are about the same size as our own Milky Way but contain only one per cent of the stars.

He says the galaxies appear to have stopped making new stars when they first fell into the cluster between seven and ten billion years ago and have been dead ever since, leading astrophysicists to label them "failed" galaxies.

This end to star formation is known as "quenching".

"Galaxies originally form when large clouds of hydrogen gas collapse and are converted to stars--if you remove that gas, the galaxy cannot grow further," Yozin says.

"Falling into a cluster is one way in which this can happen. The immense gravitational force of the cluster pulls in the galaxy, but its gas is pushed out and essentially stolen by hot gas in the cluster itself.

"For the first time, my simulations have demonstrated that these galaxies could have been quenched by the cluster as early as seven billion years ago.

"They have however avoided being ripped apart completely in this environment because they fell in with enough dark matter to protect their visible matter."

This research was motivated by the recent observational discovery of these galaxies by an American and Canadian team led Professor Pieter van Dokkum of Yale University.

Using the data the North American team published last year, Yozin was able to create computer simulations to model how the galaxies evolved into what we can see today.

###

The study was released in the journal Monthly Notices of the Royal Astronomical Society, published by Oxford University Press.

Further Information:

ICRAR is a joint venture between Curtin University and The University of Western Australia with support and funding from the State Government of Western Australia.

Original publication details:

'The quenching and survival of ultra-diffuse galaxies in the Coma cluster' in Monthly Notices of the Royal Astronomical Society. Published online on 20/7/2015 at: http://mnras.oxfordjournals.org/lookup/doi/10.1093/mnras/stv1073

Supporting Multimedia:

High resolution images are available from the following link. http://www.icrar.org/comacluster

Contact Details:

Cameron Yozin (ICRAR - UWA)
Ph: +61 8 6488 3819 E: cameron.yozin-smith@icrar.org M: +61 423 941 128

Pete Wheeler (Media Contact, ICRAR)
Ph: +61 8 6488 7758 E: pete.wheeler@icrar.org M: +61 423 982 018

UWA Media Office
Ph: +61 8 6488 3229 E: uwamedia@uwa.edu.au

http://www.icrar.org/ 

Peter Wheeler | EurekAlert!

More articles from Physics and Astronomy:

nachricht Meteoritic stardust unlocks timing of supernova dust formation
19.01.2018 | Carnegie Institution for Science

nachricht Artificial agent designs quantum experiments
19.01.2018 | Universität Innsbruck

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Artificial agent designs quantum experiments

On the way to an intelligent laboratory, physicists from Innsbruck and Vienna present an artificial agent that autonomously designs quantum experiments. In initial experiments, the system has independently (re)discovered experimental techniques that are nowadays standard in modern quantum optical laboratories. This shows how machines could play a more creative role in research in the future.

We carry smartphones in our pockets, the streets are dotted with semi-autonomous cars, but in the research laboratory experiments are still being designed by...

Im Focus: Scientists decipher key principle behind reaction of metalloenzymes

So-called pre-distorted states accelerate photochemical reactions too

What enables electrons to be transferred swiftly, for example during photosynthesis? An interdisciplinary team of researchers has worked out the details of how...

Im Focus: The first precise measurement of a single molecule's effective charge

For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. This fundamental insight of an SNSF Professor could also pave the way for future medical diagnostics.

Electrical charge is one of the key properties that allows molecules to interact. Life itself depends on this phenomenon: many biological processes involve...

Im Focus: Paradigm shift in Paris: Encouraging an holistic view of laser machining

At the JEC World Composite Show in Paris in March 2018, the Fraunhofer Institute for Laser Technology ILT will be focusing on the latest trends and innovations in laser machining of composites. Among other things, researchers at the booth shared with the Aachen Center for Integrative Lightweight Production (AZL) will demonstrate how lasers can be used for joining, structuring, cutting and drilling composite materials.

No other industry has attracted as much public attention to composite materials as the automotive industry, which along with the aerospace industry is a driver...

Im Focus: Room-temperature multiferroic thin films and their properties

Scientists at Tokyo Institute of Technology (Tokyo Tech) and Tohoku University have developed high-quality GFO epitaxial films and systematically investigated their ferroelectric and ferromagnetic properties. They also demonstrated the room-temperature magnetocapacitance effects of these GFO thin films.

Multiferroic materials show magnetically driven ferroelectricity. They are attracting increasing attention because of their fascinating properties such as...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

10th International Symposium: “Advanced Battery Power – Kraftwerk Batterie” Münster, 10-11 April 2018

08.01.2018 | Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

 
Latest News

Let the good tubes roll

19.01.2018 | Materials Sciences

How cancer metastasis happens: Researchers reveal a key mechanism

19.01.2018 | Health and Medicine

Meteoritic stardust unlocks timing of supernova dust formation

19.01.2018 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>