What is depicted in the image? The question is related to mathematics.

The image shows a diagram that appears to be related to polar coordinates or a circular region in a mathematical context. There are concentric circles, radial lines, and angle markings. There is also some text that looks like mathematical notation. Specifically, I can identify '~ 1', '60', 'β - ?' and what looks like 'φ'. The overall context suggests a problem in geometry or calculus involving angles and radii.