The Lux experiment was conducted in 2013 by a team of scientists from the University of California, Berkeley. The goal of the experiment was to search for a new particle that could explain the nature of dark matter. The team used the Large Underground Xenon (LUX) detector, located at the Sanford Underground Research Facility in South Dakota, to look for evidence of this new particle.
The LUX detector is a custom-built instrument that is designed to sensitively detect faint signals from rare events. It consists of a large tank filled with ultra-pure liquid xenon, surrounded by an array of light detectors. When a particle interacts with the xenon atoms in the tank, it produces a brief flash of light that is detected by the surrounding detectors. By analyzing the pattern and intensity of these flashes, physicists can reconstruct the properties of the particles that produced them.
In their search for dark matter, the LUX team looked for evidence of Weakly Interacting Massive Particles (WIMPs). WIMPs are one type of hypothetical particle that has been proposed as a possible explanation for dark matter. If they exist, WIMPs should be very difficult to detect because they barely interact with normal matter. However, if WIMPs do exist and make up all or most of dark matter, then they should occasionally collide with each other and produce detectable signals in experiments like LUX.
After collecting data for nearly two years, the LUX team announced their results in October 2015: they had found no evidence for WIMPs or any other type of new particle that could explain dark matter. While this result was disappointing to many physicists who had hoped to find evidence for WIMPs, it did not rule out their existence entirely; it simply meant that more sensitive experiments would be needed to find them if they do exist. The LUX experiment remains ongoing and continues to set important limits on potential candidates for dark matter.