Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


UC San Diego Researchers Advance Explanation for Star Formation

Study uses computer simulations to provide physical explanation for Larson’s Laws

A newly published paper by three UC San Diego astrophysics researchers for the first time provides an explanation for the origin of three observed correlations between various properties of molecular clouds in the Milky Way galaxy known as Larson’s Laws.

The paper, called ‘A Supersonic Turbulence Origin of Larson’s Laws’, was published this month in the Monthly Notices of the Royal Astronomical Society, Great Britain’s pre-eminent astronomy and astrophysics journal. Larson’s Laws, named so by professors teaching the three principles from the seminal 1981 paper by Richard Larson, an Emeritus Professor of Astronomy at Yale, describes the observation-based relationships of the structure and supersonic internal motions of molecular clouds where stars form.

The analysis by the UC San Diego researchers is based on recent observational measurements and data from six simulations of the interstellar medium, including effects of self-gravity, turbulence, magnetic field, and multiphase thermodynamics. The supercomputer simulations support a turbulent interpretation of Larson’s relations, and the study concludes that there are not three independent Larson laws, but that all three correlations are due to the same underlying physics, i.e. the properties of supersonic turbulence.

Larson’s original paper, published in the same journal, still inspires new advances in the understanding of molecular cloud structure formation and star formation.

“After decades of inconclusive debate about the interpretation of the correlations among molecular cloud properties that I published in 1981, it’s gratifying to see that my original idea that they reflect a hierarchy of supersonic turbulent motions is well supported by these detailed new simulations showing that the debated complicating effects of gravity, magnetic fields, and multiphase structure do not fundamentally alter the basic picture of a turbulent cascade,” said Larson in response to the new findings by the UC San Diego researchers .

“This paper is essentially the culmination of seven years of research, aided by the use of large-scale supercomputer simulations conducted at SDSC and elsewhere,” said Alexei Kritsuk, a research physicist with UC San Diego’s Physics Department and Center for Astrophysics & Space Sciences (CASS) and lead author of the paper. “Molecular clouds are the birth sites for stars, so this paper relates also to the theory of star formation.”

The researcher team includes Michael Norman, Director of the San Diego Supercomputer Center (SDSC) and a Distinguished Professor of physics at UC San Diego, and Christoph T. Lee, an undergraduate researcher with CASS. SDSC’s Trestles and Triton clusters, and now-decommissioned DataStar system, were used to generate the simulations, as well as the Kraken and Nautilus systems at the National Institute for Computational Science (NICS), at Oak Ridge National Laboratory.

“None of these new findings and insights would have been possible without the tremendous advances in supercomputer simulations that allow not only cosmologists but scientists in countless other domains an unprecedented level of resolution and data-processing speed to further their research,” said Norman, a globally recognized astrophysicist who has pioneered the use of advanced computational methods to explore the universe and its beginnings. “We believe that this paper paints the complete picture, drawing from earlier published works of ours as well as presenting new simulations that have not been published before.”

The research was supported in part by National Science Foundation (NSF) grants AST-0808184, AST-0908740, AST-1109570, and XRAC allocation MCA07S014 under the NSF’s Extreme Science and Engineering Discovery Environment (XSEDE) program.

Media Contact

Jan Zverina, 858-534-5111,
Secondary media contact:
Warren R. Froelich, 858 822-3622,

Jan Zverina | EurekAlert!
Further information:

More articles from Physics and Astronomy:

nachricht First results of NSTX-U research operations
26.10.2016 | DOE/Princeton Plasma Physics Laboratory

nachricht Scientists discover particles similar to Majorana fermions
25.10.2016 | Chinese Academy of Sciences Headquarters

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: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

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

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

3-D-printed structures shrink when heated

26.10.2016 | Materials Sciences

Indian roadside refuse fires produce toxic rainbow

26.10.2016 | Health and Medicine

First results of NSTX-U research operations

26.10.2016 | Physics and Astronomy

More VideoLinks >>>