First Four-Quark Particle Discovery?
Physicists at the University of Minnesota in Minneapolis have made a possible discovery this week that may give the scientific community a glimpse at the force that holds nuclei together – and that might just give new answers regarding the first moments in our universe’s history.
Since the 1960s, physicists have known that protons, neutrons, and hundreds of other particles are all made up of quarks. And all of these quarks can be categorized as either baryons (like neutrons and protons), which have three quarks, or mesons, which contain two. This knowledge has been the basis of every major procedure and clinical application.
But over the course of the last decade, scientists in the US, China and Japan have become increasingly interested in the possibility of a particle with more than three quarks. Of course, the quest is made substantially more difficult by the fact that there is no way to directly see a quark. Instead, they are forced to use various tests and scientific practices to measure all of a particle’s properties. Using things like charge, mass and decay, physicists are able to label a particle as only being able to exist with a certain number of quarks.
This is where the University of Minnesota’s study comes in. Scientists discovered evidence of a never before studied particle – one that can only be explained by the presence of four quarks. The particle, named Z(3900), will be the subject of much study and speculation as physicists explore all of the possibilities of a four-quark particle.