Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

SU professors test boundaries of 'new physics' with discovery of 4-quark hadron

11.04.2014

Physicist Tomasz Skwarnicki confirms existence of exotic hadron with 2 quarks, 2 anti-quarks

Physicists in Syracuse University's College of Arts and Sciences have helped confirm the existence of exotic hadrons—a type of matter that cannot be classified within the traditional quark model.

Their finding is the subject of a forthcoming article, prepared by the Large Hadron Collider beauty (LHCb) Collaboration at CERN in Geneva, Switzerland. (LHCb is a multinational experiment, designed to identify new forces and particles in the universe.) Tomasz Skwarnicki, professor of physics, is one of the paper's lead authors.

"We've confirmed the unambiguous observation of a very exotic state—something that looks like a particle composed of two quarks and two anti-quarks," says Skwarnicki, a specialist in experimental high-energy physics. "The discovery certainly doesn't fit the traditional quark model. It may give us a new way of looking at strong-interaction physics."

... more about:
»CERN »Collider »Hadron »LHCb »Syracuse »collisions »matter »physics »technique

Quarks are hard, point-like objects found within the nucleus of an atom. When quarks combine in threes, they form compound particles known as baryons. Protons are probably the best-known baryons.

Sometimes, quarks interact with corresponding anti-particles (i.e., anti-quarks), which have the same mass but opposite charges. When this happens, they form mesons. These compounds often turn up in the decay of heavy man-made particles, such as those in particle accelerators, nuclear reactors, and cosmic rays.

Mesons, baryons, and other kinds of particles that take part in strong interactions are called hadrons.

This classification remained virtually unchallenged until 2007, when an international team of 400 physicists and engineers known as the Belle Collaboration discovered an exotic particle called Z(4430), which appeared to have two quarks and two anti-quarks.

"Some experts argued that Belle's initial analysis was naïve and prone to arrive at an unjustified conclusion," says Skwarnicki, adding that other exotic states have since been observed. "As a result, many physicists concluded that there was no good evidence to prove this particle was real."

A few years later, another multinational team, known as BaBar, used a more sophisticated analysis technique, only to end up provoking more controversy over the existence of Z(4430). "BaBar didn't prove that Belle's measurements and data interpretations were wrong," Skwarnicki says. "They just felt that, based on their data, there was no need to postulate existence of this particle."

Belle responded with an even more rigorous analysis of the same data set. This time, they found statistically significant evidence for Z(4430), despite the complexity of the analysis and a large number of assumptions made about the particle's production environment.

LHCb, which, for much of the past year, has closely studied its own particle data, used Belle's and BaBar's analysis techniques. In the process, Skwarnicki and his team confirmed that Z(4430) was for real—and an exotic hadron, to boot.

"This experiment is the clincher, showing that particles made up of two quarks and two anti-quarks actually exist," Skwarnicki says. "There used to be less-clear evidence for the existence of such a particle, with one experiment being questioned by another. Now we know this is an observed structure, instead of some reflection or special feature of the data."

Professor Sheldon Stone leads a team of SU researchers at CERN (also known as the European Organization for Nuclear Research) in Geneva.

"We analyzed tens of thousands of meson decays, selected from trillions of collisions in the Large Hadron Collider [the world's largest, most powerful particle accelerator] at CERN," he says. "Because the data sample was so large, it forced us to use statistically powerful analysis that could, in turn, measure properties in an unambiguous manner. It's great to finally prove the existence of something that we had long thought was out there."

Adds Skwarnicki: "Each experiment--Belle, BaBar, and LHCb--analyzed its own data. Although it pertained to the same process, the data was collected at different times, with different colliders, and with different apparatuses for capturing outgoing particles. Our findings are unique to our experiment."

###

Housed in The College, the Department of Physics has been educating students and carrying out research for more than 125 years. Graduate and undergraduate opportunities are available in fields ranging from biological and condensed matter physics, to cosmology and particle physics, to gravitational wave detection and astrophysics.

Rob Enslin | Eurek Alert!
Further information:
http://www.syr.edu/

Further reports about: CERN Collider Hadron LHCb Syracuse collisions matter physics technique

More articles from Physics and Astronomy:

nachricht Interstellar seeds could create oases of life
28.08.2015 | Harvard-Smithsonian Center for Astrophysics

nachricht Draw out of the predicted interatomic force
28.08.2015 | Hiroshima University

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: OU astrophysicist and collaborators find supermassive black holes in quasar nearest Earth

A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.

The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...

Im Focus: What would a tsunami in the Mediterranean look like?

A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).

Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...

Im Focus: Self-healing landscape: landslides after earthquake

In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.

These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...

Im Focus: FIC Proteins Send Bacteria Into Hibernation

Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.

For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...

Im Focus: Fraunhofer IPA develops prototype of intelligent care cart

It comes when called, bringing care utensils with it and recording how they are used: Fraunhofer IPA is developing an intelligent care cart that provides care staff with physical and informational support in their day-to-day work. The scientists at Fraunhofer IPA have now completed a first prototype. In doing so, they are continuing in their efforts to improve working conditions in the care sector and are developing solutions designed to address the challenges of demographic change.

Technical assistance systems can improve the difficult working conditions in residential nursing homes and hospitals by helping the staff in their work and...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking conference in Heidelberg for outstanding mathematicians and computer scientists

20.08.2015 | Event News

Scientists meet in Münster for the world’s largest Chitin und Chitosan Conference

20.08.2015 | Event News

Large agribusiness management strategies

19.08.2015 | Event News

 
Latest News

Interstellar seeds could create oases of life

28.08.2015 | Physics and Astronomy

An ounce of prevention: Research advances on 'scourge' of transplant wards

28.08.2015 | Health and Medicine

Fish Oil-Diet Benefits May be Mediated by Gut Microbes

28.08.2015 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>