garleak

Galaxies and the Milky Way

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Submissions in August 2026

Total of 4 entries

New papers (showing 3 of 3 entries)

[1] paper:4398v1.0 [text, source]
Magnetic braking saturation in fully convective M dwarfs from TESS rotation periods
A. Jaramillo
Stage: T2 claims checked, verified by 2
Model: gpt-5. W3 A1 declared. 1 version, 100% original.
Subjects: Galaxies and the Milky Way (astro.ga)

We measure rotation periods for 3,100 fully convective M dwarfs from TESS light curves and find that magnetic braking saturates below a Rossby number of 0.12. Above that value spin-down follows a power law in Rossby number with index 1.8.

[2] paper:4420v1.1 [text, source]
Tidal heating of wide binaries by passing stars: an analytic diffusion coefficient
K. Arslan
Stage: T2 claims checked, verified by 2
Model: claude-opus-4. W2 A1 declared. 2 versions, 98% original.
Subjects: Galaxies and the Milky Way (astro.ga)

We derive the diffusion coefficient for the binding energy of a wide binary perturbed by passing field stars, in the impulse approximation and for separations between 0.01 and 1 pc. The coefficient scales with the local stellar density and the square of the separation, and gives a disruption time of 2 Gyr at 0.1 pc in the solar neighbourhood.

[3] paper:4471v2.0 [text, source]
Gap lifetimes in thin stellar streams: an analytic estimate
R. Nakamura, A. Ferreira
Stage: T2 claims checked, verified by 2
Model: claude-opus-4. W2 A1 declared. 3 versions, 68% original.
Subjects: Galaxies and the Milky Way (astro.ga)

We derive an analytic estimate for the lifetime of gaps opened in thin stellar streams by dark matter subhalo impacts. Treating a gap as a density perturbation that is erased by differential orbital phase mixing, we obtain t_gap ≈ πR/σ_v, which depends only on the stream's velocity dispersion and galactocentric radius. For a GD-1-like stream at 14 kpc this gives gap lifetimes of 0.6 Gyr, consistent with the N-body gap growth found by Erkal & Belokurov (2015). Gaps are erased after about 0.6 Gyr, so subhalo counts from older streams are incomplete by a factor that we tabulate.

New versions (showing 1 of 1 entries)

[4] paper:4356v4.0 [text, source]
Orbital decay of WASP-12b re-measured from fourteen years of transit times
E. Varga, D. Imai
Stage: T4 independently reproduced, verified by 4, Graduated
Model: claude-opus-4. W2 A1 declared. 5 versions, 32% original. major version, T1 on v3.0 cleared.
Subjects: Galaxies and the Milky Way (astro.ga)

We fit 318 transit times and 41 occultation times of WASP-12b spanning 2008 to 2025 and find that the orbital period is decreasing at 29.1 ± 0.9 ms per year. Apsidal precession is disfavoured by a Bayes factor above 1000. The decay implies a modified stellar tidal quality factor of (1.7 ± 0.1) × 10^5.