This is awesome news! thank you
My pleasure!
They say that the still-to-be-confirmed, outermost belt is tilted by 45 deg, but not the others. As such, and even if the sketch and the animation assume coplanarity of the three belts, it seems not to be observationally established.
Any assumptions about the true mass at this point rely on that assumption. There's no way to know for sure at this point. The confidently detected disk's inclination is unknown, just inferred by coplanarity from the uncertainly-detected outer disk. Which makes the inclination of Proxima Centauri b a lot less certain.
However, if the innermost belt (~10 times farther than Prox b) was confirmed and if the position of its inner and outer boundary were well enough constrained, we could certainly have some constraints on the planet's mass. The constraints would certainly be far weaker if we have to rely on the confidently detected, intermediate belt. Or, more exactly, we could have constraints on the (mass, inclination) parameter. If you are talking about modelling the inner disk edge from the spectral energy distribution, you have to assume the b planet is alone to assume it's mass is responsible for shaping the inner disk wall. If the latter, you can probably infer the inclination, and the HARPS/Red Dots campaign does suggest a second planet is in the system at < 100ish days.
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