About Synthetic Defous Blur Data

[emjay73]

The paper reads, 'For defocus blur, we use the built-in functionality to render depth-of-field images. We fix the aperture and randomly choose a focus plane between the nearest and the furthest depth'.
Can I get a specified aperture size for each synthetic data?
All of them use the same aperture size?

[emjay73]

Also, the image folder of defocuspool data is empty.