A sub-Neptune planet around TOI-1695 discovered and characterized with SPIRou and TESS

F. Kiefer, G. Hébrard, E. Martioli, E. Artigau, R. Doyon, J. F. Donati, C. Cadieux, A. Carmona, D. R. Ciardi, P. I. Cristofari, L. De Almeida, P. Figueira, E. Gaidos, E. Gonzales, A. Lecavelier Des Etangs, K. G. Stassun, L. Arnold, B. Benneke, I. Boisse, X. BonfilsN. J. Cook, P. Cortés-Zuleta, X. Delfosse, J. Dias Do Nascimento, M. Fausnaugh, W. Fong, P. Fouqué, T. Forveille, J. Gomes Da Silva, K. Hesse, Kóspál, H. Lewis, C. F. Liu, J. H.C. Martins, M. Paegert, S. Seager, H. Shang, J. D. Twicken, T. Vandal, S. Vinatier, T. Widemann, J. N. Winn

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


TOI-1695 is a V-mag = 13 M-dwarf star from the northern hemisphere at 45 pc from the Sun, around which a 3.134-day periodic transit signal from a super-Earth candidate was identified in TESS photometry. With a transit depth of 1.3 mmag, the radius of candidate TOI-1695.01 was estimated by the TESS pipeline to be 1.82 R with an equilibrium temperature of ~620 K. We successfully detected a reflex motion of the star and establish that it is due to a planetary companion at an orbital period consistent with the photometric transit period, thanks to a year-long radial-velocity monitoring of TOI-1695 by the SPIRou infrared spectropolarimeter. We used and compared different methods to reduce and analyze those data. We report a 5.5 detection of the planetary signal, giving a mass of 5.5±1.0 M and a radius of 2.03±0.18 R. We derive a mean equilibrium planet temperature of 590±90 K. The mean density of this small planet of 3.6±1.1 g cm3 is similar (1.7 lower) than that of the Earth. It leads to a nonnegligible fraction of volatiles in its atmosphere with fH,He = 0.280.23+0.46% or fwater = 23±12%. TOI-1695 b is a new sub-Neptune planet at the border of the M-dwarf radius valley that can help test formation scenarios for super-Earth and sub-Neptune-like planets.

Original languageEnglish (US)
Article numberA136
JournalAstronomy and Astrophysics
StatePublished - Feb 1 2023

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science


  • Planets and satellites: detection
  • Planets and satellites: fundamental parameters
  • Planets and satellites: individual: TOI-1695 b
  • Techniques: photometric
  • Techniques: radial velocities


Dive into the research topics of 'A sub-Neptune planet around TOI-1695 discovered and characterized with SPIRou and TESS'. Together they form a unique fingerprint.

Cite this