Need help to understand the Thompson Sampling (TS) implementation in the TuRBO tutorial

[Ted12345678]

I am looking into the TuRBO tutorial https://botorch.org/tutorials/turbo_1, I am having a hard time to understand the perturbation mask. For example, how is 20.0 is determined in the following code?

    # Create a perturbation mask
    prob_perturb = min(20.0 / dim, 1.0)

Any theory or tutorial about the perturbation mask and its usage in TS implementation?

Thank you very much in advance!

[Balandat]

@dme65, @sdaulton can you help with this?