What is the half-life of Iridium-192 (192 Ir)?

The half-life of Iridium-192 (192 Ir) is approximately 74 days. This radioactive isotope is widely used in medical applications, particularly in brachytherapy for cancer treatment. The half-life indicates the time required for half of a given amount of radioactive material to decay. In the context of medical dosimetry, the relatively short half-life of Iridium-192 allows for effective tumor treatment while minimizing the duration of radiation exposure to the surrounding healthy tissues.

Understanding the half-life is crucial for planning treatment schedules and dosimetry calculations, ensuring that the dose delivered is both precise and within safe limits. The other options listed do not accurately represent Iridium-192's half-life, as they correspond to other isotopes or are significantly longer than what is relevant for the clinical applications of Iridium-192 in radiation therapy.