Scientists from Fermilab uncover the Omega b baryon

Sep 11, 2008 15:23 GMT  ·  By

Physicists from the University of Michigan stumbled upon the proton's distant cousin, the Omega b baryon, as a result of their research at the Fermi National Accelerator Laboratory (Fermilab) in Illinois.

While CERN and their contested and heavily discussed LHC still hold first pages of newspapers and fuel news and documentaries worldwide, people at Fermilab provide results. Although the heavy particle was very widely spread soon after the Big Bang, currently it is quite rare, which makes its discovery even more important.

Quarks are the smallest of particles which, together with leptons, form the visible matter. They come in six “flavors”: up, down, strange, charm, top and bottom, which physicists categorize in three families. Different combinations of three quarks form baryons, the lightest of which are the proton and the neutron. Protons and neutrons are built of quarks that fall in the first family of up and down quarks. Finally, Omega b is the first baryon formed only from quarks that come from the other two families, since it has two strange quarks and one bottom quark.

A professor from the Physics Department, Jianming Qian, states, “this discovery helps us understand how matter was formed in the universe. It shows the critical success of the quark model and gives us new insight into the strong force, which binds quarks together to form larger particles”. Along with physics professor Homer Neal and postdoctoral fellow Eduard de la Cruz Burelo, Qian is credited with having done the hardest research work.

Instead of waiting for other data, the three experts insisted on re-examining the already gathered one and “Their persistence paid off,” as Dmitri Denisov, Fermilab's DZero spokesman stated. This success is not the first of the three researchers. Last year, they also discovered a particle named the cascade b baryon. DZero, the project that led to the success of the two discoveries, numbers 600 other physicists from 90 institutions worldwide and is funded by the National Science Foundation, the U.S. Department of Energy and several other international agencies.

Qian explained that it was extremely difficult, as they had to develop algorithms that would enable them to examine about 100 trillion particle collisions (sounds familiar?) in order to find 18 events presenting the expected features of the Omega b baryon's decay. Here's the difficult part: protons and anti-protons traveling at near-light speed collide and produce “exotic” particles, such as the one recently discovered. The new baryon then travels only for about 1 mm before decaying into other particles.