Subscribe free to our newsletters via your
. 24/7 Space News .




TIME AND SPACE
CERN collider to become the world's fastest stopwatch?
by Staff Writers
Vienna, Austria (SPX) Nov 13, 2012


Two lead atoms collide, creating a quark gluon plasma, which can emit ultra short laser pulses. Credit: Vienna University of Technology.

Heavy ion collisions at CERN should be able to produce the shortest light pulses ever created. This was demonstrated by computer simulations at the Vienna University of Technology. The pulses are so short that they cannot even be measured by today's technological equipment.

Now, a method has been proposed to create the world's most precise stopwatch for the world's shortest light pulses, using a detector which is going to be installed at CERN in 2018.

Phenomena taking place on very short time scales are often investigated using ultra short laser pulses. Today, pulse durations of the order of attoseconds (billionths of a billionths of a second, 10^-18 seconds) can be created.

But these records could soon be broken: "Atomic nuclei in particle colliders like the LHC at CERN or at RHIC can create light pulses which are still a million times shorter than that", says Andreas Ipp from TU Vienna.

In the ALICE experiment at CERN, lead nuclei are collided almost at the speed of light. The debris of the scattered nuclei together with new particles created by the power of the impact form a quark-gluon plasma, a state of matter which is so hot that even protons and neutrons melt.

Their building blocks - quarks and gluons - can move independently without being bound to each other. This quark-gluon plasma only exists for several yoctoseconds (10^-24 seconds).

Ideas From Astronomy
From the quark-gluon plasma created in a particle collider, light pulses can be emitted, which carry valuable information about the plasma. However, conventional measurement techniques are much too slow to resolve flashes on a yoctosecond timescale.

"That's why we make use of the Hanbury Brown-Twiss effect, an idea which was originally developed for astronomical measurements", says Andreas Ipp.

In a Hanbury Brown-Twiss experiment, correlations between two different light detectors are studied. That way, the diameter of a star can be calculated very precisely.

"Instead of studying spatial distances, the effect can just as well be used for measuring time intervals", says Andreas Ipp. The calculations he did together with Peter Somkuti show that the yoctosecond pulses of the quark-gluon plasma could be resolved by a Hanbury Brown-Twiss experiment.

"It would be hard to do, but it would definitely be achievable", says Ipp. This experiment would not require any additional expensive detectors, it could be done with the "forward calorimeter", which is supposed to go on line at CERN in 2018. That way, the ALICE-experiment could become the world's most accurate stopwatch.

The Enigmas of the Plasma
There are still many open questions in quark-gluon plasma physics. It has an extraordinarily low viscosity, it is thinner than any liquid we know.

Even if it starts out in a state of extreme disequilibrium, it reaches a thermal equilibrium extremely fast. Studying the light pulses from the quark-gluon plasma could yield valuable new information to better understand this state of matter.

In the future, the light pulses could perhaps even be used for nuclear research. "Experiments using two light pulses are often used in quantum physics", says Andreas Ipp.

"The first pulse changes the state of the object under investigation, a second pulse is used shortly after that, to measure the change."

With yoctosecond light pulses, this well-established approach could be used in areas which up until now have been completely inaccessible to this kind of research.

.


Related Links
Vienna University of Technology
Understanding Time and Space






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








TIME AND SPACE
Swiss watches tick to Chinese heartbeat
Geneva (AFP) Nov 11, 2012
With the Chinese increasingly coveting European luxury goods, Swiss watchmakers are eyeing a huge new market for their wares, but disagree on the best way of capturing it. The question being mulled by famous Swiss watch brands is whether to create more specialty editions aimed at appealing specifically to the Chinese or instead simply wait for fast-shifting Chinese tastes to adapt to Europea ... read more


TIME AND SPACE
China's Chang'e-3 to land on moon next year

Moon crater yields impact clues

Study: Moon basin formed by giant impact

NASA's LADEE Spacecraft Gets Final Science Instrument Installed

TIME AND SPACE
Mars orbiter back online after system swap

What Arctic Rocks Say About Mars: An Interview with Hans Amundsen

More Driving And Imaging At 'Matijevic Hill'

Curiosity Team Switches Back to Earth Time

TIME AND SPACE
Get some bed rest - all 21 days of it

Latest China military hardware displayed at airshow

Obama Win Keeps NASA's Space Plans on Course

Next steps into the final frontier

TIME AND SPACE
Mr Xi in Space

China plans manned space launch in 2013: state media

China to launch manned spacecraft

Tiangong 1 Parked And Waiting As Shenzhou 10 Mission Prep Continues

TIME AND SPACE
Crew Prepares for Spacewalk After Progress Docks

Crew Preparing for Cargo Ship, Spacewalk

Russian cargo ship docks with ISS: official

Packed Week Ahead for Six-Member Crew

TIME AND SPACE
Arianespace's fourth Spaceport mission with Soyuz ready for fueling

Ariane 5's sixth launch of 2012

Ariane 5 is poised for Arianespace's launch with the EUTELSAT 21B and Star One C3 satellites

Ariane 5 orbits EUTELSAT 21B and Star One C3 satellites

TIME AND SPACE
Discovery of a Giant Gap in the Disk of a Sun-like Star May Indicate Multiple Planets

New habitable zone super-Earth found in exosolar system

Cosmic sprinklers explained in active planetary nebula

Nearby six-planet system could be life friendly

TIME AND SPACE
Microsoft holds Windows Phone 8 hopes

Making a better invisibility cloak

Head of Windows unit leaves Microsoft

Online TEDTalks hit billion-view milestone




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement