Post-Envelope Period Distribution for Double White Dwarf Progenitors Across Efficiency and Structure Parameters

This paper examines a grid of progenitors represented by a 1.5 solar-mass giant, core 0.55 and envelope 0.95 solar masses at 180 solar radii, with a 0.75 solar-mass companion, evaluated across efficiencies from 0.1 to 1.0 and structure parameters from 0.3 to 1.5. Using published input values and the standard energy comparison between envelope binding and orbital release, the calculation addresses the specific budget that decides the outcome for this pairing. The headline results are: period_min_days = 0.069; period_max_days = 13.08; period_median_days = 1.907. The method, inputs and limitations are stated in full so that any reader can reproduce or rescale every number from the deposited calculation script. A single required-efficiency calculation can always be dismissed as a choice of inputs. Agreement and disagreement with published values for this class are reported at their actual size, and the conclusions are limited to what the budget arithmetic supports.