This is added in the collected table of specific_analysis/relax_disp/parameter_object.py.
This is related to: task #7793: (https://gna.org/task/?7793) Speed-up of dispersion models.
Discussed in post http://thread.gmane.org/gmane.science.nmr.relax.devel/5986.
In any function, these default values can get accessed by:
from specific_analyses.relax_disp.parameter_object import Relax_disp_params
PARAMS = Relax_disp_params()
PARAMS.default_value('pA')
PARAMS.grid_upper('pA')