New results from the STAR detector at the Relativistic Heavy Ion Collider are calling into question a long-standing idea about what gives protons one of their basic quantum properties, according to ScienceDaily.
The study, published in Science, suggests that gluons — the particles that hold quarks together — may help carry and conserve baryon number. Researchers say the evidence points to a Y-shaped gluon junction connecting the proton’s three main quarks.
If that result holds up, it would challenge the traditional view that baryon number belongs only to the quarks inside a proton. Zhangbu Xu of Kent State University said physicists have usually assumed each of the three valence quarks carries one-third of the baryon number.
The findings also matter beyond proton structure, because baryon number conservation is tied to particle collisions, the stability of protons, and even the broader question of why matter exists in the universe. The STAR collaboration says it developed a way to test the idea using different types of collisions at RHIC.
Researchers noted that the simplified textbook model does not capture the full complexity of protons, which also contain gluons and fleeting quark-antiquark pairs. The team says its results strongly support the idea that baryon number may be transported more favorably by gluons in this special configuration.
