210At

210At is the common notation for the isotope Astatine-210. Astatine is a chemical element with the symbol At and atomic number 85. It is an extremely rare and highly radioactive element.

Astatine-210 has a half-life of approximately 8.1 hours. During its decay, it primarily emits alpha particles, transforming into Bismuth-206. In a smaller fraction of decays, it can undergo electron capture, also resulting in Bismuth-206. Due to its intense radioactivity and short half-life, 210At is not found in significant quantities in nature and is typically produced artificially in laboratories, often through nuclear reactions involving other elements like radium or bismuth.

The study of astatine isotopes, including 210At, is of interest in nuclear physics and radiochemistry. Its properties are relevant to understanding the behavior of heavy elements and their decay chains. Due to its radioactivity, handling and research involving 210At require specialized safety precautions. Its potential applications are limited due to its short half-life and rarity, though research into targeted alpha therapy in cancer treatment has explored certain astatine isotopes, albeit typically longer-lived ones.