Which type of radiation is known for being the most penetrating?

Gamma rays are known for their high penetrating power due to their nature as electromagnetic radiation with very short wavelengths and high energy. Unlike alpha particles, which can be stopped by a sheet of paper, and beta particles, which can be halted by a few millimeters of plastic or glass, gamma rays can pass through various materials, including human tissue and thick lead or concrete barriers. This makes them particularly hazardous as they can easily penetrate to internal organs, leading to significant exposure risks in situations like nuclear accidents or certain medical treatments.

Neutrons, while also capable of penetrating materials effectively, tend to interact differently and are more effective in causing reactions in specific materials, such as in nuclear fission contexts. Thus, while they can penetrate matter, gamma rays still hold the title as the most penetrating type of radiation overall.