Scientists hope to build a new subatomic particle smasher
A new 4.5-billion-yuan (about $618 million) particle collider is on the cards for China in the coming years, the South China Morning Post (SCMP) reports. Specifically designed to test the "Standard Model" of particle physics, construction of the facility will begin, it is hoped, within three years. Called the Super Tau-Charm Facility (STCF), once operational, the facility will produce huge amounts of subatomic particles known as tau leptons and charm quarks to help better understand how they come together to form larger matter structures.
Charming to be sure
“STCF will allow China to lead the world in tau-charm physics and related technologies for decades to come,” said project chief scientist Zhao Zhengguo of the University of Science and Technology of China. “It will also address cutting-edge scientific questions such as the nature of strong interaction and why the universe is dominated by matter instead of antimatter,” Zhao added.
Like the existing Beijing Electron Positron Collider (BEPC) that has been operational since 1990, the STCF will operate by accelerating electrons and their antiparticles, known as positrons, to almost the speed of light. It will then collide them to produce numerous subatomic particles. An internal spectrometer will then record subatomic particles' trajectories, energies, and electric charges, aiding scientists in reconstructing reaction processes.
Throughout its history, BEPC has facilitated numerous groundbreaking discoveries by scientists from around the globe, including the first-ever precise measurement of tau's mass in the 1990s. However, as Zhao explained, BEPC's position in Beijing restricted its ability to advance to a higher level of precision. To address this, STCF is being planned for construction in Southern China as a natural expansion of BEPC. A conceptual design report released in March revealed that STCF would have a similar layout to the existing tau-charm factory in Beijing but will be more than twice its size.
The linear accelerator of the new device. SCMP reports will measure 1,310 feet (400 meters) in length. Additionally, the two rings used for storing electrons and positrons will have a circumference of approximately 2,625 feet (800 meters) each.
Due to its increased size, the STCF will boost collision rates by up to 100 times, according to the team behind its design. This means that it will collect the same amount of data in just three days that it takes BEPC an entire year to gather. The new collider will also explore a previously unstudied energy region, paving the way for uncharted territory and potentially discovering new physics beyond the Standard Model.
Features advanced technology
It will also incorporate advanced technologies, including high-power electron and positron sources, superconducting magnets, high-precision detectors, and ultra-fast/ultra-weak signal readout electronics. The team behind the STCF hopes to complete the development of these technologies by the end of 2025 and construct the collider during the 15th Five-Year Plan period (2026-2030).
Possible locations for the STCF include Hefei in Anhui province, Shaoxing in Zhejiang province, and Zhengzhou in Henan province. However, the construction of the STCF will need approval from China's National Development and Reform Commission before anything can get underway.