Featured Research

from universities, journals, and other organizations

Theorists propose a new way to shine -- and a new kind of star: 'electroweak'

Date:
December 15, 2009
Source:
Case Western Reserve University
Summary:
Physicists propose there may be a new stage for some dying stars. Dubbed electroweak stars, they are fueled by the conversion of quarks to leptons, which prevents or staves off collapse into a black hole.

Artist's vision of a neutron star centered in a disk of hot plasma drawn from its red companion star. Physicists have theorized that an electroweak star might be the next step before total collapse of a neutron star into a black hole.
Credit: W. Feimer (Allied Signal), GSFC, NASA

Dying, for stars, has just gotten more complicated.

For some stellar objects, the final phase before or instead of collapsing into a black hole may be what a group of physicists is calling an electroweak star.

Glenn Starkman, a professor of physics at Case Western Reserve University, together with former graduate students and post-docs De-Chang Dai and Dejan Stojkovic, now at the State University of New York in Buffalo, and Arthur Lue, at MIT's Lincoln Lab, offer a description of the structure of an electroweak star in a paper submitted to Physical Review Letters.

Ordinary stars are powered by the fusion of light nuclei into heavier ones -- such as hydrogen into helium in the center of our sun. Electroweak stars, they theorize, would be powered by the total conversion of quarks -- the particles that make up the proton and neutron building blocks of those nuclei -- into much lighter particles called leptons. These leptons include electrons, but especially elusive -- and nearly massless -- neutrinos.

"This is a process predicted by the well-tested Standard Model of particle physics," Starkman said. At ordinary temperatures it is so incredibly rare that it probably hasn't happened within the visible universe anytime in the last 10 billion years, except perhaps in the core of these electroweak stars and in the laboratories of some advanced alien civilizations, he said.

In their dying days, stars smaller than 2.1 times our sun's mass die and collapse into neutron stars -- objects dense enough that the neutrons and protons push against each other. More massive stars are thought to head toward collapse into a black hole. But at the extreme temperatures and densities that might be reached when a star begins to collapse into a black hole, electroweak conversion of quarks into leptons should proceed at a rapid rate, the scientists say.

The energy generated could halt the collapse, much as the energy generated by nuclear fusion prevents ordinary stars like the Sun from collapsing. In other words, an electroweak star is the possible next step before total collapse into a black hole. If the electroweak burning is efficient, it could consume enough mass to prevent what's left from ever becoming a black hole.

Most of the energy eventually emitted from electroweak stars is in the form of neutrinos, which are hard to detect. A small fraction comes out as light and this is where the electroweak star's signature will likely be found, Starkman, said. But, "To understand that small fraction, we have to understand the star better than we do."

And until they do, it's hard to know how we can tell electroweak stars from other stars.

There's time, however, to learn. The theorists have calculated that this phase of a star's life can last more than 10 million years -- a long time for us, though just an instant in the life of a star.


Story Source:

The above story is based on materials provided by Case Western Reserve University. Note: Materials may be edited for content and length.


Journal Reference:

  1. De-Chang Dai, Arthur Lue, Glenn Starkman, Dejan Stojkovic. Electroweak stars: how nature may capitalize on the standard model's ultimate fuel. Physical Review Letters, 2009; (submitted)

Cite This Page:

Case Western Reserve University. "Theorists propose a new way to shine -- and a new kind of star: 'electroweak'." ScienceDaily. ScienceDaily, 15 December 2009. <www.sciencedaily.com/releases/2009/12/091214131132.htm>.
Case Western Reserve University. (2009, December 15). Theorists propose a new way to shine -- and a new kind of star: 'electroweak'. ScienceDaily. Retrieved April 16, 2014 from www.sciencedaily.com/releases/2009/12/091214131132.htm
Case Western Reserve University. "Theorists propose a new way to shine -- and a new kind of star: 'electroweak'." ScienceDaily. www.sciencedaily.com/releases/2009/12/091214131132.htm (accessed April 16, 2014).

Share This



More Space & Time News

Wednesday, April 16, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Baby Moon 'Peggy' Spotted In Saturn's Rings

New Baby Moon 'Peggy' Spotted In Saturn's Rings

Newsy (Apr. 15, 2014) A bump in the rings could be a half-mile-wide miniature moon. It was found by accident in Cassini probe images. Video provided by Newsy
Powered by NewsLook.com
NASA Showcases Lunar Eclipse

NASA Showcases Lunar Eclipse

AP (Apr. 15, 2014) Star gazers in parts of North and South America got a rare treat early Tuesday morning - a total eclipse of the moon. (April 15) Video provided by AP
Powered by NewsLook.com
Spacecrafts Could Use Urine As Fuel Source

Spacecrafts Could Use Urine As Fuel Source

Newsy (Apr. 15, 2014) New research says the urea from urine could be recycled for fuel. Urea is filtered out of wastewater when making drinking water. Video provided by Newsy
Powered by NewsLook.com
NASA Approves Mon. Space Station Supply Launch

NASA Approves Mon. Space Station Supply Launch

AP (Apr. 13, 2014) NASA decided Sunday to stick with the planned launch of the SpaceX cargo ship, despite a critical computer outage at the space station.Liftoff is scheduled for 4:58 p.m. Monday from Cape Canaveral. (April 13) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins