Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Magnetic fields slow down stars

12.06.2012
Scientists have proved the existence of a magnetic effect that could explain why solar-like stars spin very slowly at the end of their lifetime.

Researchers from the Leibniz-Institut für Astrophysik Potsdam (AIP) made simulations of the magnetic fields of stars and compared the results with measurements from a laboratory experiment done at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR).


Numerical Simulations show a strong disturbation of the magnetic fields inside a star for higher than critical magnetic field values. Credits: AIP

The aim and result of this experiment was to detect, for the first time, a magnetic instability that had been theoretically predicted but never directly observed in a star. This magnetic effect would enhance the viscosity of hot plasma inside a star, leading to a strong deceleration of its core.

“We have known for years that the Tayler instability is an effective mechanism to explain the deceleration of stars, but until now there was no proof of its existence,“ says Günther Rüdiger, the principal investigator at AIP. “This experiment confirms our numerical predictions very well!“ adds Marcus Gellert, who conducted computer simulations to prepare the experiment.

In order to correlate with the low rotation rates observed in white dwarfs, or neutron stars, which are stars at the end of their life cycle, the core rotation rate of a solar-like star would have to drop by ninety percent. A permanently active magnetic instability could decelerate the core of a star very effectively and would explain observations in a simple and elegant way.
The extent to which these laboratory results can be transferred to a real star has to be shown via new simulations and comparisons with observations in the near future. The confirmation of the Tayler instability underlines the importance of magnetic fields in stars and could be an important step towards creating more consistent models of stellar evolution.

The GATE experiment is a successor to the award-winning “PROMISE“ experiment which, in 2010, proved the existence of so-called magnetorotational instability (MRI), demonstrating a second successful partnership between astronomers from AIP and scientists at HZDR in shedding more light on stars in the lab.

The key topics of the Leibniz Institute for Astrophysics are cosmic magnetic fields and extragalactic astrophysics. A considerable part of the institute's efforts aim at the development of research technology in the fields of spectroscopy, robotic telescopes, and e-science. The AIP is the successor of the Berlin Observatory founded in 1700 and of the Astrophysical Observatory of Potsdam founded in 1874.
The latter was the world's first observatory to emphasize explicitly the research area of astrophysics. The AIP is a foundation according to civil law and is a member of the Leibniz Association. The Leibniz Association is a network of 86 independent research institutes and scientific service facilities, which strive for scientific solutions for major social challenges.

Science contact: Prof. Dr. G. Rüdiger, gruediger@aip.de; Dr. M. Gellert, mgellert@aip.de, Tel.: +49 331 7499 530
Press contact:
Dr. Gabriele Schönherr / Kerstin Mork, presse@aip.de Tel.: +49 331 7499 469
Weitere Informationen:

http://arxiv.org/abs/1201.2318
Rüdiger G., Gellert M., Schultz M., Strassmeier K.G., Stefani F., Gundrum Th., Seilmayer M., Gerbeth G.: Critical fields and growth rates of the Tayler instability as probed by a columnar gallium experiment

http://prl.aps.org/abstract/PRL/v108/i24/e244501
Martin Seilmayer, Frank Stefani u.a.: Evidence for transient Tayler instability in a liquid metal experiment, in: Physical Review Letter

Kerstin Mork | Leibniz-Institut für Astrophysik
Further information:
http://www.aip.de

More articles from Physics and Astronomy:

nachricht Significantly more productivity in USP lasers
06.12.2016 | Fraunhofer-Institut für Lasertechnik ILT

nachricht Shape matters when light meets atom
05.12.2016 | Centre for Quantum Technologies at the National University of Singapore

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: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>