TY - JOUR
T1 - TOI-663
T2 - a newly discovered multi-planet system with three transiting mini-Neptunes orbiting an early M star
AU - Cointepas, M.
AU - Bouchy, F.
AU - Almenara, J. M.
AU - Bonfils, X.
AU - Astudillo-Defru, N.
AU - Knierim, H.
AU - Stalport, M.
AU - Mignon, L.
AU - Grieves, N.
AU - Bean, J.
AU - Brady, M.
AU - Burt, J.
AU - Canto Martins, B. L.
AU - Collins, K. A.
AU - Collins, K. I.
AU - Delfosse, X.
AU - de Medeiros, J. R.
AU - Demory, B.-O.
AU - Dorn, C.
AU - Forveille, T.
AU - Fukui, A.
AU - Gan, T.
AU - Gómez Maqueo Chew, Y.
AU - Halverson, S.
AU - Helled, R.
AU - Helm, I.
AU - Hirano, T.
AU - Horne, K.
AU - Howell, S. B.
AU - Isogai, K.
AU - Kasper, D.
AU - Kawauchi, K.
AU - Livingston, J. H.
AU - Massey, B.
AU - Matson, R. A.
AU - Murgas, F.
AU - Narita, N.
AU - Palle, E.
AU - Relles, H. M.
AU - Sabin, L.
AU - Schanche, N.
AU - Schwarz, R. P.
AU - Seifahrt, A.
AU - Shporer, A.
AU - Stefansson, G.
AU - Sturmer, J.
AU - Tamura, M.
AU - Tan, T.-G.
AU - Twicken, J. D.
AU - Watanabe, N.
AU - Wells, R. D.
AU - Wilkin, F. P.
AU - Ricker, G. R.
AU - Seager, S.
AU - Winn, J. N.
AU - Jenkins, J. M.
N1 - Funding: The authors acknowledge funding from the European Research Council under the ERC Grant Agreement n. 337591-ExTrA. This work is partly supported by JSPS KAKENHI Grant Numbers JP17H04574, JP18H05439, JP 18H05442, JP19K14783, JP20K14521, JP21H00035, JP21K13955, JP21K20376, Grant-in-Aid for JSPS Fellows, Grant Number JP20J21872, JST CREST Grant Number JPMJCR1761, and Astrobiology Center SATELLITE Research project AB022006. M.T. is supported by JSPS KAKENHI grant Nos.18H05442. C.D. acknowledges support from the Swiss National Science Foundation under grant TMSGI2_211313. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE 1746045. G.S. acknowledges support provided by NASA through the NASA Hubble Fellowship grant HST-HF2-51519.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. J.R.M. and B.L.C.M. acknowledge continuous grants from the brazilian funding agencies CAPES (Finance Code 001) and CNPq. The material is based upon work supported by NASA under award number 80GSFC21M0002.
PY - 2024/5/1
Y1 - 2024/5/1
N2 - We present the detection of three exoplanets orbiting the early M dwarf TOI-663 (TIC 54962195; V = 13.7 mag, J = 10.4 mag, R* = 0.512 ± 0.015 R☉, M* = 0.514 ± 0.012 M☉, d = 64 pc). TOI-663 b, c, and d, with respective radii of 2.27 ± 0.10 R🜨, 2.26 ± 0.10 R🜨, and 1.92 ± 0.13 R🜨 and masses of 4.45 ± 0.65 M🜨, 3.65 ± 0.97 M🜨, and <5.2 M🜨 at 99%, are located just above the radius valley that separates rocky and volatile-rich exoplanets. The planet candidates are identified in two TESS sectors and are validated with ground-based photometric follow-up, precise radial-velocity measurements, and high-resolution imaging. We used the software package juliet to jointly model the photometric and radial-velocity datasets, with Gaussian processes applied to correct for systematics. The three planets discovered in the TOI-663 system are low-mass mini-Neptunes with radii significantly larger than those of rocky analogs, implying that volatiles, such as water, must predominate. In addition to this internal structure analysis, we also performed a dynamical analysis that confirmed the stability of the system. The three exoplanets in the TOI-663 system, similarly to other sub-Neptunes orbiting M dwarfs, have been found to have lower densities than planets of similar sizes orbiting stars of different spectral types.
AB - We present the detection of three exoplanets orbiting the early M dwarf TOI-663 (TIC 54962195; V = 13.7 mag, J = 10.4 mag, R* = 0.512 ± 0.015 R☉, M* = 0.514 ± 0.012 M☉, d = 64 pc). TOI-663 b, c, and d, with respective radii of 2.27 ± 0.10 R🜨, 2.26 ± 0.10 R🜨, and 1.92 ± 0.13 R🜨 and masses of 4.45 ± 0.65 M🜨, 3.65 ± 0.97 M🜨, and <5.2 M🜨 at 99%, are located just above the radius valley that separates rocky and volatile-rich exoplanets. The planet candidates are identified in two TESS sectors and are validated with ground-based photometric follow-up, precise radial-velocity measurements, and high-resolution imaging. We used the software package juliet to jointly model the photometric and radial-velocity datasets, with Gaussian processes applied to correct for systematics. The three planets discovered in the TOI-663 system are low-mass mini-Neptunes with radii significantly larger than those of rocky analogs, implying that volatiles, such as water, must predominate. In addition to this internal structure analysis, we also performed a dynamical analysis that confirmed the stability of the system. The three exoplanets in the TOI-663 system, similarly to other sub-Neptunes orbiting M dwarfs, have been found to have lower densities than planets of similar sizes orbiting stars of different spectral types.
KW - Planets and satellites: detection
KW - Stars: low-mass
KW - Techniques: photometric
KW - Techniques: radial velocities
UR - https://www.scopus.com/pages/publications/85192824547
U2 - 10.1051/0004-6361/202346899
DO - 10.1051/0004-6361/202346899
M3 - Article
AN - SCOPUS:85192824547
SN - 0004-6361
VL - 685
JO - Astronomy & Astrophysics
JF - Astronomy & Astrophysics
M1 - A19
ER -