[phenixbb] Unusually low B factors

Hi all, I have produced xenon derivatives for SAD phasing of several standard proteins by placing them under xenon gas pressure and then immediately flash freezing in liquid nitrogen. Everything has worked out nicely as far as successful phasing, nice models, and low R factors. Now I've noticed that the B values have decreased from initial processing values. Several rounds of manual changes and phenix.refine have caused B values to decrease each round of refinement to values of around 10 (I guess 20 is a more common value). Does anyone know why this is happening or what the explanation might be? I'm not sure what other information to include so please contact to discuss further. Thanks! ~Brennan