The True Stellar Obliquity of a Sub-Saturn Planet from the Tierras Observatory and KPF
Fuente:
arXiv
Saved in:
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866913823206670336 |
|---|---|
| author | Tamburo, Patrick Yee, Samuel W. García-Mejía, Juliana Stefánsson, Gudmundur Charbonneau, David Bieryla, Allyson Howard, Andrew W. Isaacson, Howard Fulton, Benjamin J. Householder, Aaron |
| author_facet | Tamburo, Patrick Yee, Samuel W. García-Mejía, Juliana Stefánsson, Gudmundur Charbonneau, David Bieryla, Allyson Howard, Andrew W. Isaacson, Howard Fulton, Benjamin J. Householder, Aaron |
| contents | We measure the true obliquity of TOI-2364, a K dwarf with a sub-Saturn-mass ($M_p = 0.18\,M_J$) transiting planet on the upper edge of the hot Neptune desert. We used new Rossiter-McLaughlin observations gathered with the Keck Planet Finder to measure the sky-projected obliquity $λ= 7$$^\circ$$^{+10^\circ}_{-11^\circ}$. Combined with a stellar rotation period of $23.47\pm0.29$ days measured with photometry from the Tierras Observatory, this yields a stellar inclination of $90^{\circ} \pm 13^{\circ}$ and a true obliquity $ψ= 15.6$$^\circ$$^{+7.7^\circ}_{-7.3^\circ}$, indicating that the planet's orbit is well aligned with the rotation axis of its host star. The determination of $ψ$ is important for investigating a potential bimodality in the orbits of short-period sub-Saturns around cool stars, which tend to be either aligned with or perpendicular to their host stars' spin axes. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2505_03628 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | The True Stellar Obliquity of a Sub-Saturn Planet from the Tierras Observatory and KPF Tamburo, Patrick Yee, Samuel W. García-Mejía, Juliana Stefánsson, Gudmundur Charbonneau, David Bieryla, Allyson Howard, Andrew W. Isaacson, Howard Fulton, Benjamin J. Householder, Aaron Earth and Planetary Astrophysics We measure the true obliquity of TOI-2364, a K dwarf with a sub-Saturn-mass ($M_p = 0.18\,M_J$) transiting planet on the upper edge of the hot Neptune desert. We used new Rossiter-McLaughlin observations gathered with the Keck Planet Finder to measure the sky-projected obliquity $λ= 7$$^\circ$$^{+10^\circ}_{-11^\circ}$. Combined with a stellar rotation period of $23.47\pm0.29$ days measured with photometry from the Tierras Observatory, this yields a stellar inclination of $90^{\circ} \pm 13^{\circ}$ and a true obliquity $ψ= 15.6$$^\circ$$^{+7.7^\circ}_{-7.3^\circ}$, indicating that the planet's orbit is well aligned with the rotation axis of its host star. The determination of $ψ$ is important for investigating a potential bimodality in the orbits of short-period sub-Saturns around cool stars, which tend to be either aligned with or perpendicular to their host stars' spin axes. |
| title | The True Stellar Obliquity of a Sub-Saturn Planet from the Tierras Observatory and KPF |
| topic | Earth and Planetary Astrophysics |
| url | https://arxiv.org/abs/2505.03628 |