7-Feb-2023: Muons Penetrate Ancient Xi'an Fortress Wall

Muography in Xi’an

CORMIS (Cosmic Ray Muon Imaging System) was used to examine the fortress wall of Xi’an, an ancient city in China. Muons can penetrate hundreds of metres of stone surfaces. Muography is a novel and innovative tool for archaeologists to investigate large-scale sites.

Muon Detection

• Muons are subatomic particles created by cosmic rays. Muons are highly unstable and exist for 2.2 microseconds.
• They can penetrate hundreds of metres of matter, unlike electrons.

Muography is a method of scanning large structures using muons. Muography has applications in archaeology, customs security, and internal imaging of volcanoes.

Archaeological Applications of Muography

• Muography can investigate large-scale archaeological sites.
• Luis Alvarez used Muography in the late 1960s to look for hidden rooms in the Pyramid of Khafre in Giza.
• Scientists have used Muography to analyze Mount Vesuvius in Italy.
• In 2015, Muography was used to look inside the Fukushima nuclear reactors after the 2011 earthquake and tsunami in Japan.