First results from LZ
"With only 60 days of data dating, LZ is the most sensitive dark matter search experiment in the world. LIP is a founding member of LZ."
The international collaboration LUX-ZEPLIN (LZ), of which LIP is part, has just presented its first scientific results. In a paper made available at https://lz.lbl.gov/ the LZ researchers show that, with only 60 days of data acquisition, LZ is the most sensitive dark matter experiment in the world.
Dark matter is expected to make up about 85% of the matter in the Universe. It has never been directly observed (it does not emit, absorb, or interact with light in any way), but its gravitational effects indirectly alert us to its presence.
The LZ detector is installed at a depth of 1.5 kilometers in a former gold mine converted into a laboratory (Sanford Lab, USA) to protect it from cosmic radiation reaching the Earth's surface. It consists of 10 tons of ultra-pure liquid xenon contained in a titanium vessel and observed by 494 light sensors capable of detecting the tiniest amount of light. If the dark matter interacts with normal matter, even very weakly, then it is possible that it collides with a xenon core and produces a scintillation signal that can be measured by the light sensors.
The collaboration includes 250 scientists and engineers from 35 institutions in the US, UK, Portugal and South Korea. The Portuguese team is composed of researchers, PhD students and MSc students from LIP, which is a founding member of the LZ collaboration and has made many key contributions to the experiment. The LIP node involved in LZ is based at the Physics Department of the University of Coimbra.
The news was released simultaneously in the various countries that are members of the collaboration yesterday, July 7, 2022, at 18:00 Lisbon time.