_version_ 1866918308795645952
author Alves, Douglas R.
Jenkins, James S.
Vinés, José I.
Moyano, Maximilano
Anderson, David R.
Magliano, Christian
Covone, Giovanni
Stassun, Keivan G.
Soubkiou, Abderahmane
Gillen, Edward
Battley, Matthew P.
Hughes, Alexander
Armstrong, David J.
Saha, Suman
Hawthorn, Faith
Wheatley, Peter J.
Collins, Karen A.
Schwarz, Richard P.
Srdoc, Gregor
Apergis, Ioannis
Zivave, Tafadzwa
Lendl, Monika
Tofflemire, Benjamin M.
Doty, John P.
Hedges, Christina
Mireles, Ismael
Burleigh, Matthew R.
Kendall, Alicia
Harvey, George T.
Goad, Michael R.
Casewell, Sarah L.
Edkins, Troy
author_facet Alves, Douglas R.
Jenkins, James S.
Vinés, José I.
Moyano, Maximilano
Anderson, David R.
Magliano, Christian
Covone, Giovanni
Stassun, Keivan G.
Soubkiou, Abderahmane
Gillen, Edward
Battley, Matthew P.
Hughes, Alexander
Armstrong, David J.
Saha, Suman
Hawthorn, Faith
Wheatley, Peter J.
Collins, Karen A.
Schwarz, Richard P.
Srdoc, Gregor
Apergis, Ioannis
Zivave, Tafadzwa
Lendl, Monika
Tofflemire, Benjamin M.
Doty, John P.
Hedges, Christina
Mireles, Ismael
Burleigh, Matthew R.
Kendall, Alicia
Harvey, George T.
Goad, Michael R.
Casewell, Sarah L.
Edkins, Troy
contents Observations have shown that planets similar to Neptune are rarely found orbiting Sun-like stars with periods up to ~4 days, defining the so-called Neptune desert region. Therefore, the detection of each individual planet in this region holds a high value, providing detailed insights into how such a population came to form and evolve. Here we report the detection of TOI-333b, a Neptune desert planet with a mass, radius, and bulk density of 20.1 $\pm$ 2.4 M$_{\oplus}$, 4.26 $\pm$ 0.11 R$_{\oplus}$, and 1.42 $\pm$ 0.21 \gccc, respectively. The planet orbits a F7V star every 3.78 d, whose mass, radius and effective temperature are of 1.2 $\pm$ 0.1 \msun, 1.10 $\pm$ 0.03 \rsun, and 6241$^{+73}_{-62}$ K, respectively. TOI-333b is likely younger than 1 Gyr, which is supported by the presence of the doublet Li line around 6707.856 textup{~Å} and its comparison to Li abundances in open clusters with well constrained ages. The planet is expected to host only 8.5$^{+10.9}_{-8.3}\%$ gas-to-core mass ratio for a H/He envelope. On the other hand, irradiated ocean world models predict 20$^{+11}_{-10}\%$ H$_2$O mass fraction with a core fraction of 35$^{+20}_{-23}\%$. Therefore, we expect that TOI-333b internal composition may be dominated by a pure rocky composition with almost no H/He envelope, or a rocky world with almost equal mass fraction of water. Finally, TOI-333b is more massive and larger than 77$\%$ and 82$\%$ of its Neptune desert counterparts, respectively, while its host ranks among the hottest known for Neptune Desert planets, making this system a unique laboratory to study the evolution of such planets around hot stars.
format Preprint
id arxiv_https___arxiv_org_abs_2511_13832
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle TOI-333b: A Neptune Desert planet around a F7V star
Alves, Douglas R.
Jenkins, James S.
Vinés, José I.
Moyano, Maximilano
Anderson, David R.
Magliano, Christian
Covone, Giovanni
Stassun, Keivan G.
Soubkiou, Abderahmane
Gillen, Edward
Battley, Matthew P.
Hughes, Alexander
Armstrong, David J.
Saha, Suman
Hawthorn, Faith
Wheatley, Peter J.
Collins, Karen A.
Schwarz, Richard P.
Srdoc, Gregor
Apergis, Ioannis
Zivave, Tafadzwa
Lendl, Monika
Tofflemire, Benjamin M.
Doty, John P.
Hedges, Christina
Mireles, Ismael
Burleigh, Matthew R.
Kendall, Alicia
Harvey, George T.
Goad, Michael R.
Casewell, Sarah L.
Edkins, Troy
Earth and Planetary Astrophysics
Solar and Stellar Astrophysics
Observations have shown that planets similar to Neptune are rarely found orbiting Sun-like stars with periods up to ~4 days, defining the so-called Neptune desert region. Therefore, the detection of each individual planet in this region holds a high value, providing detailed insights into how such a population came to form and evolve. Here we report the detection of TOI-333b, a Neptune desert planet with a mass, radius, and bulk density of 20.1 $\pm$ 2.4 M$_{\oplus}$, 4.26 $\pm$ 0.11 R$_{\oplus}$, and 1.42 $\pm$ 0.21 \gccc, respectively. The planet orbits a F7V star every 3.78 d, whose mass, radius and effective temperature are of 1.2 $\pm$ 0.1 \msun, 1.10 $\pm$ 0.03 \rsun, and 6241$^{+73}_{-62}$ K, respectively. TOI-333b is likely younger than 1 Gyr, which is supported by the presence of the doublet Li line around 6707.856 textup{~Å} and its comparison to Li abundances in open clusters with well constrained ages. The planet is expected to host only 8.5$^{+10.9}_{-8.3}\%$ gas-to-core mass ratio for a H/He envelope. On the other hand, irradiated ocean world models predict 20$^{+11}_{-10}\%$ H$_2$O mass fraction with a core fraction of 35$^{+20}_{-23}\%$. Therefore, we expect that TOI-333b internal composition may be dominated by a pure rocky composition with almost no H/He envelope, or a rocky world with almost equal mass fraction of water. Finally, TOI-333b is more massive and larger than 77$\%$ and 82$\%$ of its Neptune desert counterparts, respectively, while its host ranks among the hottest known for Neptune Desert planets, making this system a unique laboratory to study the evolution of such planets around hot stars.
title TOI-333b: A Neptune Desert planet around a F7V star
topic Earth and Planetary Astrophysics
Solar and Stellar Astrophysics
url https://arxiv.org/abs/2511.13832