_version_ 1866913418136518656
author Nabbie, Emma
Huang, Chelsea X.
Burt, Jennifer A.
Armstrong, David J.
Mamajek, Eric E.
Adibekyan, Vardan
Sousa, Sérgio G.
Lopez, Eric D.
Thorngren, Daniel P.
Fernández, Jorge
Li, Gongjie
Jenkins, James S.
Vines, Jose I.
da Silva, João Gomes
Wittenmyer, Robert A.
Bayliss, Daniel
Briceño, César
Collins, Karen A.
Dumusque, Xavier
Horne, Keith D.
Keniger, Marcelo F.
Law, Nicholas
Lillo-Box, Jorge
Liu, Shang-Fei
Mann, Andrew W.
Nielsen, Louise Dyregaard
Osborn, Ares
Relles, Howard M.
Rodrigues, José J.
Bell, Juan
Srdoc, Gregor
Stockdale, Chris
Strøm, Paul A.
Gardner-Watkins, Cristilyn N.
Wheatley, Peter J.
Wright, Duncan J.
Zhou, George
Ziegler, Carl
Ricker, George R.
Seager, Sara
Vanderspek, Roland
Winn, Joshua W.
Jenkins, Jon M.
Fausnaugh, Michael
Kunimoto, Michelle
Osborn, Hugh P.
Quinn, Samuel N.
Wohler, Bill
author_facet Nabbie, Emma
Huang, Chelsea X.
Burt, Jennifer A.
Armstrong, David J.
Mamajek, Eric E.
Adibekyan, Vardan
Sousa, Sérgio G.
Lopez, Eric D.
Thorngren, Daniel P.
Fernández, Jorge
Li, Gongjie
Jenkins, James S.
Vines, Jose I.
da Silva, João Gomes
Wittenmyer, Robert A.
Bayliss, Daniel
Briceño, César
Collins, Karen A.
Dumusque, Xavier
Horne, Keith D.
Keniger, Marcelo F.
Law, Nicholas
Lillo-Box, Jorge
Liu, Shang-Fei
Mann, Andrew W.
Nielsen, Louise Dyregaard
Osborn, Ares
Relles, Howard M.
Rodrigues, José J.
Bell, Juan
Srdoc, Gregor
Stockdale, Chris
Strøm, Paul A.
Gardner-Watkins, Cristilyn N.
Wheatley, Peter J.
Wright, Duncan J.
Zhou, George
Ziegler, Carl
Ricker, George R.
Seager, Sara
Vanderspek, Roland
Winn, Joshua W.
Jenkins, Jon M.
Fausnaugh, Michael
Kunimoto, Michelle
Osborn, Hugh P.
Quinn, Samuel N.
Wohler, Bill
contents The recent discoveries of Neptune-sized ultra-short period planets (USPs) challenge existing planet formation theories. It is unclear whether these residents of the Hot Neptune Desert have similar origins to smaller, rocky USPs, or if this discrete population is evidence of a different formation pathway altogether. We report the discovery of TOI-3261b, an ultra-hot Neptune with an orbital period $P$ = 0.88 days. The host star is a $V = 13.2$ magnitude, slightly super-solar metallicity ([Fe/H] $\simeq$ 0.15), inactive K1.5 main sequence star at $d = 300$ pc. Using data from the Transiting Exoplanet Survey Satellite and the Las Cumbres Observatory Global Telescope, we find that TOI-3261b has a radius of $3.82_{-0.35}^{+0.42}$ $R_{\oplus}$. Moreover, radial velocities from ESPRESSO and HARPS reveal a mass of $30.3_{-2.4}^{+2.2}$ $M_{\oplus}$, more than twice the median mass of Neptune-sized planets on longer orbits. We investigate multiple mechanisms of mass loss that can reproduce the current-day properties of TOI-3261b, simulating the evolution of the planet via tidal stripping and photoevaporation. Thermal evolution models suggest that TOI-3261b should retain an envelope potentially enriched with volatiles constituting $\sim$5% of its total mass. This is the second highest envelope mass fraction among ultra-hot Neptunes discovered to date, making TOI-3261b an ideal candidate for atmospheric follow-up observations.
format Preprint
id arxiv_https___arxiv_org_abs_2407_04225
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Surviving in the Hot Neptune Desert: The Discovery of the Ultra-Hot Neptune TOI-3261b
Nabbie, Emma
Huang, Chelsea X.
Burt, Jennifer A.
Armstrong, David J.
Mamajek, Eric E.
Adibekyan, Vardan
Sousa, Sérgio G.
Lopez, Eric D.
Thorngren, Daniel P.
Fernández, Jorge
Li, Gongjie
Jenkins, James S.
Vines, Jose I.
da Silva, João Gomes
Wittenmyer, Robert A.
Bayliss, Daniel
Briceño, César
Collins, Karen A.
Dumusque, Xavier
Horne, Keith D.
Keniger, Marcelo F.
Law, Nicholas
Lillo-Box, Jorge
Liu, Shang-Fei
Mann, Andrew W.
Nielsen, Louise Dyregaard
Osborn, Ares
Relles, Howard M.
Rodrigues, José J.
Bell, Juan
Srdoc, Gregor
Stockdale, Chris
Strøm, Paul A.
Gardner-Watkins, Cristilyn N.
Wheatley, Peter J.
Wright, Duncan J.
Zhou, George
Ziegler, Carl
Ricker, George R.
Seager, Sara
Vanderspek, Roland
Winn, Joshua W.
Jenkins, Jon M.
Fausnaugh, Michael
Kunimoto, Michelle
Osborn, Hugh P.
Quinn, Samuel N.
Wohler, Bill
Earth and Planetary Astrophysics
The recent discoveries of Neptune-sized ultra-short period planets (USPs) challenge existing planet formation theories. It is unclear whether these residents of the Hot Neptune Desert have similar origins to smaller, rocky USPs, or if this discrete population is evidence of a different formation pathway altogether. We report the discovery of TOI-3261b, an ultra-hot Neptune with an orbital period $P$ = 0.88 days. The host star is a $V = 13.2$ magnitude, slightly super-solar metallicity ([Fe/H] $\simeq$ 0.15), inactive K1.5 main sequence star at $d = 300$ pc. Using data from the Transiting Exoplanet Survey Satellite and the Las Cumbres Observatory Global Telescope, we find that TOI-3261b has a radius of $3.82_{-0.35}^{+0.42}$ $R_{\oplus}$. Moreover, radial velocities from ESPRESSO and HARPS reveal a mass of $30.3_{-2.4}^{+2.2}$ $M_{\oplus}$, more than twice the median mass of Neptune-sized planets on longer orbits. We investigate multiple mechanisms of mass loss that can reproduce the current-day properties of TOI-3261b, simulating the evolution of the planet via tidal stripping and photoevaporation. Thermal evolution models suggest that TOI-3261b should retain an envelope potentially enriched with volatiles constituting $\sim$5% of its total mass. This is the second highest envelope mass fraction among ultra-hot Neptunes discovered to date, making TOI-3261b an ideal candidate for atmospheric follow-up observations.
title Surviving in the Hot Neptune Desert: The Discovery of the Ultra-Hot Neptune TOI-3261b
topic Earth and Planetary Astrophysics
url https://arxiv.org/abs/2407.04225