Topic: Physics

Researchers at the University of Tennessee have made three key discoveries about how gold is created in stars. They used a special facility to study rare atomic nuclei and found new information about beta decay and neutron emission.

Nuclear physicists have long struggled to understand how certain unstable atomic nuclei break apart, allowing heavy elements like gold to form. Now, researchers at the University of Tennessee (UT) have made three important discoveries that clarify this process. Their findings could help improve models of stellar events that create heavy elements and predict the behavior of exotic atomic nuclei.

The team used CERN's ISOLDE Decay Station to study rare isotopes of indium-134. They found that when indium-134 decays, it produces excited forms of tin-134, tin-133, and tin-132. Using a neutron detector built at UT, the scientists discovered three major findings.

The most significant result was the first measurement of neutron energies associated with beta-delayed two-neutron emission. This process occurs only in exotic nuclei, which are unstable and exist briefly. The energy needed to separate two neutrons from the nucleus is extremely small, but in this experiment it was large enough to measure.

The team also observed a long-predicted single particle neutron state in tin-133. According to Professor Robert Grzywacz, the nucleus begins in an excited state and must release energy to stabilize. This discovery provides valuable insight for improving models that describe how stellar events create heavy elements like gold.

These findings mark the first detailed study of two-neutron emission from a nucleus that lies along the r-process pathway. The results provide valuable insight for improving models that describe how stellar events create heavy elements like gold.

Why It Matters

Understanding how gold is created in stars can help us better predict the formation of other heavy elements, which are important for understanding the universe's evolution and the creation of life on Earth.

Key Facts

• Researchers at the University of Tennessee made three key discoveries about how gold is created in stars.
• The team used CERN's ISOLDE Decay Station to study rare isotopes of indium-134.
• They found that beta-delayed two-neutron emission occurs only in exotic nuclei, which are unstable and exist briefly.
• The team also observed a long-predicted single particle neutron state in tin-133.
• These findings provide valuable insight for improving models that describe how stellar events create heavy elements like gold.

Key Terms

Beta decay

A process where an atomic nucleus releases energy by changing its type of particles.

Implications

Understanding how gold is created in stars can help us better predict the formation of other heavy elements, which are important for understanding the universe's evolution and the creation of life on Earth.