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Validation: src/mors/physicalmodel.py

This page tracks the @pytest.mark.reference_pinned tests that anchor the behaviour of mors.physicalmodel against published sources.

Test id Reference Scope
tests/test_physicalmodel.py::test_saturated_xray_ratio_matches_johnstone_value Johnstone et al. (2020) saturated X-ray ratio, calibrated on the Spada et al. (2013) 2 models Pins the saturated X-ray-to-bolometric ratio at the saturation Rossby number to Rx_sat = 5.135e-4, the value the rotation-activity model uses (see High-energy emission and activity).
tests/test_physicalmodel.py::test_solar_runaway_greenhouse_limit Kopparapu et al. (2013) 1, Table 3 Pins the runaway-greenhouse boundary for a solar analogue to (Lbol / Seff)**0.5 with Seff = 1.0385, giving about 0.98 AU at one solar luminosity.

Re-derivation note

physicalmodel.py holds the rotation, activity, and high-energy emission relations of the stellar model. Two anchors pin it:

The X-ray activity relation is a broken power law in Rossby number with a saturated branch Rx = C1 * Ro**beta1 for Ro <= Ro_sat. At the saturation Rossby number the two branches meet at Rx_sat = 5.135e-4. The reference-pinned test evaluates the relation at the saturation point and pins that value, so a regression in the saturation constant or the branch selection is caught. A companion test walks a point on each side of the threshold to check the branch dispatch.

The habitable-zone boundaries follow the Kopparapu et al. (2013) effective stellar flux Seff = Seff_sun + a*T + b*T**2 + c*T**3 + d*T**4 with T = Teff - 5780, and the boundary distance is aOrb = (Lbol / Seff)**0.5. For a solar analogue T = 0, so Seff = Seff_sun; the runaway-greenhouse coefficient Seff_sun = 1.0385 places the boundary at (1 / 1.0385)**0.5, about 0.98 AU for one solar luminosity. The test pins that solar-limit boundary, and a companion test asserts the full ordering of the five boundaries from Recent Venus (innermost) to Early Mars (outermost).

Anchor type

Published benchmark. The saturated X-ray ratio is the calibrated model value; the habitable-zone boundary is the Kopparapu et al. (2013) solar limit. Companion physics_invariant tests cover the positivity of the emission quantities, the band conservation Lxuv = Lx + Leuv, the torque antisymmetry, the saturation monotonicity, and the ordering of the habitable-zone boundaries.

Cross-references

References

  1. R. K. Kopparapu, R. Ramirez, J. F. Kasting, et al., Habitable zones around main-sequence stars: new estimates, The Astrophysical Journal, 765(2), 131, 2013. ↩

  2. F. Spada, P. Demarque, Y.-C. Kim, A. Sills, The radius discrepancy in low-mass stars: single versus binaries, The Astrophysical Journal, 776(2), 87, 2013. ↩