R5Tools v1.1.0

[1.1.0] - 2026-08-28

Added

• Support for radii in arcseconds (in addition to pc and kpc).
• Option to supply either surface brightness (μ) or total apparent magnitude (m_tot).
• When a physical radius (pc/kpc) is given together with m_tot, the code asks for the original angular size so the conversion can be performed.
• Automatic conversion of major-axis radii to circularised (geometric-mean) radii using the axis ratio b/a.
• Both circularised and major-axis values of R_e, R_5 and r_{-3} are now reported when a major-axis radius is supplied.
• Clearer messaging when an approximation is outside its validity range (e.g. R_g/R_5).

Changed

• Dynamical mass section header now explicitly states that circularised radii are used.
• Interactive prompts improved for clarity and robustness.

Notes

• All scientific calculations use the circularised geometry.
• Backward-compatible with version 1.0.0 for pure programmatic use of the scientific functions.

R5Tools v1.0.0

Initial release of R5Tools accompanying Graham (2026, MNRAS, in press), "R_e, or not R_e: Developing R_5 ≡ R_-2 as a scale radius for galaxy sizes, masses, and mass-to-light ratios".

• Exact Sérsic b_n and R_5 / R_e relations.
• Deprojection and 3D enclosed light fraction F_3D.
• Refined M_-3 mass and (M_dyn/L)_-3 estimators.
• Mass-follows-light virial coefficients K_V(n, 0.1 R_e) and K_V(n, inf).