Breakthrough in Particle Physics: Unveiling the Quark-Gluon Plasma
In a significant advancement in molecular physics, a new particle detector has successfully passed a crucial test, proving its readiness to detect the “ashes” of quark-gluon plasma. This unique state of matter filled the universe immediately after the Big Bang, and understanding it is key to comprehending the origins of the universe.
The Experiment at RHIC Particle Accelerator
The sPHENIX detector is the latest experiment at the RHIC particle accelerator at Brookhaven National Laboratory in New York. RHIC is the second most powerful particle accelerator in the world after the Large Hadron Collider (LHC), where protons and heavy ion elements like gold are smashed at nearly the speed of light to create quark-gluon plasma, a state of matter that existed briefly after the Big Bang.
Quark-gluon plasma exists only at extremely high temperatures and densities and is considered a “soup” of free quarks and gluons, the fundamental particles that make up protons. Understanding quark-gluon plasma may reveal the conditions that prevailed in the universe during the first microseconds and how this led to the formation of protons and neutrons—and eventually the matter that fills the universe today.
Passing the “Standard Candle” Test
To test the readiness of the sPHENIX detector, a test known in molecular physics as the “standard candle” was used. This test should not be confused with Type 1a stellar explosions that astronomers use to measure cosmic distances. In this context, the “standard candle” refers to a known constant measurement used to assess the detector’s accuracy.
The sPHENIX project passed this test by measuring the number of particles produced when gold ions collide at nearly the speed of light and by measuring the collective energy of these particles. The detector was also able to determine the number of charged particles released during a direct collision between gold ions and those released in a partial collision between gold ions.
New Insights into Quark-Gluon Plasma
When quark-gluon plasma is formed in particle accelerators, it lasts for an extremely brief period, no more than a sextillionth of a second, reaching temperatures of several trillion degrees. During this brief period, the particles behave as a perfect fluid rather than a collection of random particles.
As the plasma cools, this strange state disappears, and protons and neutrons form, rapidly moving away from the site of the initial molecular collisions. Scientists aim to measure the particles resulting from the plasma’s decay to reconstruct the properties of the plasma that vanishes in an instant.
Conclusion
The sPHENIX detector is a next-generation replacement for the previous PHENIX experiment at Brookhaven National Laboratory. With its ability to measure 15,000 molecular collisions per second, the detector provides an advanced system for tracking the number, shapes, energies, and paths of particles. Through these advancements, sPHENIX offers us a deeper understanding of the micro-world of particles and the conditions of the early universe, marking a significant step towards understanding the roots of the universe’s origin.