Final answer:
The references provided do not address fiber bend radius, but typically G.652 standard single-mode fiber has a minimum bend radius around 10 times the outer diameter of the fiber.
Step-by-step explanation:
The question is about finding the smallest allowable bend radius for G.652 standard single-mode fiber. However, the reference information provided does not directly address fiber bend radius but relates to the topic of diffraction and the behavior of light. To find the minimum allowable bend radius for G.652 fiber, one must refer to telecommunications standards or manufacturer specifications, as this information is technical and specific to the material properties of the fiber. Typically, single-mode fibers like G.652 have a minimum bend radius around 10 times the outer diameter of the fiber, which ensures that the integrity of the signal and the physical structure of the fiber are maintained and not compromised by bending.