HD 206893 B - low-mass companion orbiting an F5V star with a debris disc

Projected separation 10 AU, inner edge of the debris disc is at ~50 AU. Depending on the age of the system, HD 206893 B is estimated to be in the range 24–73 Jupiter masses.

Milli et al. "Discovery of a low-mass companion inside the debris ring surrounding the F5V star HD206893"
https://arxiv.org/abs/1612.00333

Now with radial velocity data and astrometry...

Grandjean et al. "Constraining the properties of HD 206893 B. A combination of radial velocity, direct imaging, and astrometry data"
https://arxiv.org/abs/1906.02058

The RVs do not seem to be compatible with the properties of HD 206893 B, instead there may be an additional ~15 Jupiter mass object in an inner orbit (possibly around 1.6–4 years). Dynamical mass of HD 206893 B is estimated to be around 10 Jupiter masses but the inner companion (if it exists) may affect this.

Lazarus wrote:

Now with radial velocity data and astrometry... Dynamical mass of HD 206893 B is estimated to be around 10 Jupiter masses but the inner companion (if it exists) may affect this.

It seemingly exists: here HD 206893 C (or "c") is mentioned (and lies within the HZ too!).

GRAVITY K-band spectroscopy of HD 206893 B: brown dwarf or exoplanet

Quote :

We aim to reveal the nature of the reddest known substellar companion HD 206893 B by studying its near-infrared colors and spectral morphology and by investigating its orbital motion. We fit atmospheric models for giant planets and brown dwarfs and perform spectral retrievals with petitRADTRANS and ATMO on the observed GRAVITY, SPHERE, and GPI spectra of HD 206893 B. To recover its unusual spectral features, we include additional extinction by high-altitude dust clouds made of enstatite grains in the atmospheric model fits. We also infer the orbital parameters of HD 206893 B by combining the ∼100 μas precision astrometry from GRAVITY with data from the literature and constrain the mass and position of HD 206893 C based on the Gaia proper motion anomaly of the system. The extremely red color and the very shallow 1.4 μm water absorption feature of HD 206893 B can be fit well with the adapted atmospheric models and spectral retrievals. Altogether, our analysis suggests an age of ∼3-300 Myr and a mass of ∼5-30 _Jup for HD 206893 B, which is consistent with previous estimates but extends the parameter space to younger and lower-mass objects. The GRAVITY astrometry points to an eccentric orbit (e=0.29^+0.06_-0.11) with a mutual inclination of <34.4 deg with respect to the debris disk of the system. While HD 206893 B could in principle be a planetary-mass companion, this possibility hinges on the unknown influence of the inner companion on the mass estimate of 10⁺⁵_-4 M_Jup from radial velocity and Gaia as well as a relatively small but significant Argus moving group membership probability of ∼61%. However, we find that if the mass of HD 206893 B is <30 M_Jup, then the inner companion HD 206893 C should have a mass between ∼8-15 _Jup.

I come to know of a putative third outer planet within the debris disk too, though quoted from a previous paper.

Lazarus wrote:

Now with radial velocity data and astrometry... Dynamical mass of HD 206893 B is estimated to be around 10 Jupiter masses but the inner companion (if it exists) may affect this.

HD 206893 c is confirmed
Direct Discovery of the Inner Exoplanet in the HD206893 System
https://arxiv.org/abs/2208.04867
Yet EPE lists it as “candidate”. Have they read the paper title?