The Memory Share of the Radiated Budget: An Energy Partition Between the Oscillatory Waves and the Permanent Step

Of the energy a merger radiates, how much is carried by the memory part of the signal as opposed to the oscillatory waves that sourced it? This paper computes that partition from the second-order structure of the effect, showing that the memory is suppressed relative to its source by an additional power of the compactness of the system, and it evaluates the resulting fraction for representative mergers. The partition matters beyond bookkeeping: it explains why an effect can be simultaneously a firm prediction of the nonlinear theory and a negligible channel of energy loss, and it sets the scale for any proposal to detect memory calorimetrically rather than by displacement. For GW150914 the primary waves carry a fraction 0.0462 of the total mass energy, 4.62 per cent, at symmetric mass ratio 0.247. The memory's share of the primary radiated energy is 0.0111, or 1.11 per cent, a second-order suppression on top of the primary's own few-per-cent share. As a fraction of the total mass energy of the system, the memory carries 5.11e-04, which is the number that governs any calorimetric detection idea. The memory carries 1.11 per cent of the radiated energy of GW150914 and 5.1e-04 of the system's total mass energy, a second-order share that explains its firm theoretical status alongside its observational difficulty. This study is computed from stated assumptions and published catalogue values; it is simulated, not measured.