GWTC Remnant
Classifier

Physics model

Fits from Jimenez-Forteza, Keitel, Husa et al. 2017, PRD 95, 064024 (arXiv:1611.00332), nonspinning limit (chi1=chi2=0):

• Radiated energy: Erad(eta) = 3.145*eta^4 - 0.847*eta^3 + 0.561*eta^2 + (1 - 2*sqrt(2)/3)*eta [Eq. 21, Table VII]
• Final spin: chi_f = L'_orb(eta) via [Eq. 7, Table I]; L'_orb = (1.3*a3*eta^3 + 5.24*a2*eta^2 + 2*sqrt(3)*eta) / (2.88*a5*eta + 1)
• Remnant mass: Mf = M*(1 - Erad(eta))
• Chirp mass: Mc = (m1*m2)^(3/5) / M^(1/5)

Fractional exponents in chirp mass use a deterministic pure-JS fdlibm port (det.pow) so the execution_hash is identical across browser V8, Worker V8, and zkVM guest environments.

PI mass gap caveat

The pair-instability mass-gap edges (~60-130 M-sun) are model-dependent (nuclear reaction rates, rotation, metallicity -- Farmer et al. 2019, Woosley 2019). These are not sharp thresholds. For GW231123-class events, waveform-systematics uncertainty is noted by Chatterjee et al. 2025 (arXiv:2509.09161).

Citations

• Jimenez-Forteza et al. 2017, PRD 95, 064024 (arXiv:1611.00332)
• Farmer et al. 2019, ApJ 887, 53 (DOI 10.3847/1538-4357/ab518b)
• Woosley 2019, ApJ 878, 49 (DOI 10.3847/1538-4357/ab1b41)
• Chatterjee et al. 2025, arXiv:2509.09161
• GW231123 candidate: arXiv:2507.08219