Skip to content

Validation: src/mors/star.py

This page tracks the @pytest.mark.reference_pinned tests that anchor the behaviour of mors.star against a published source.

Test id Reference Source page Scope
tests/test_star.py::test_star_reproduces_solar_luminosity_at_solar_age Spada et al. (2013) 1 solar-calibrated tracks; IAU 2015 Resolution B3 nominal solar luminosity 2013ApJ...776...87S Checks that a 1 Msun star at the solar age (4.57 Gyr) reproduces the nominal solar luminosity in erg/s to within 15%, validating both the track calibration and the internal Lsun-to-erg/s conversion, with a 0.3 Msun discrimination guard.

Re-derivation note

The Star class couples the Spada et al. (2013) stellar-structure tracks with a rotation-and-activity model and exposes Star.Value(age, key). Structural keys (Rstar, Lbol) are returned in cgs units: Lbol in erg/s, converted from the tracks' native solar-luminosity units by multiplying by the nominal solar luminosity. Activity keys (Leuv) depend on the rotation history the chosen time integrator produces.

The Spada et al. (2013) models are solar-calibrated: a 1 Msun star at the solar age reproduces the Sun. In this implementation the solar-mass track at 4.57 Gyr returns a bolometric luminosity within roughly 10% of the IAU nominal L_sun = 3.828e33 erg/s. Pinning against that nominal value tests two things at once: that the track calibration is correct, and that the solar-luminosity to erg/s unit conversion inside Star.Value is applied with the right constant and exponent.

Scale: a 0.3 Msun main-sequence star is more than a factor of ten fainter than the Sun, far outside the 15% tolerance, so a regression that read the wrong mass track or dropped the cgs conversion (a factor of ~4e33) would fail loudly. The discrimination guard asserts the 0.3 Msun luminosity is below one tenth of the solar-mass value.

Anchor type

Published benchmark. The Spada et al. (2013) solar-calibrated tracks and the IAU nominal solar luminosity are the benchmark. Companion physics_invariant tests pin Star.Value against the model output for both time-integration methods (test_star_value_default_integrator, test_star_value_forward_euler_integrator) and assert positivity of the radius, bolometric luminosity, and EUV luminosity.

Cross-references

  • src/mors/star.py: the Star class, Star.Value, and the cgs unit conversions applied to the track output.
  • src/mors/stellarevo.py: supplies the underlying structural interpolation; see docs/Validation/stellarevo.md.
  • PROTEUS reads Star.Value for the stellar luminosity and EUV history during the stellar-evolution step.

References

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