We report the confirmation of three transiting exoplanets orbiting, (LSPM J0902+7138), (G 2--21), and (Wolf 346) that were initially detected by through ground-based photometry and radial velocity follow-up measurements with CARMENES. The planets present short orbital periods of 4. 65, 5. 88, and 2. 59 days, and they orbit early-M dwarfs (M2. 0, V, M1. 5, V, and M3. 0, V, respectively). We were able to precisely determine the radius of all three planets with a precision of < 7, %, the mass of with a precision of 19, %, and upper mass limits for and The radius of is 2. 33 _, its mass is 7. 7 ± 1. 5, , and the mean density is 0. 61 ± 0. 15, M_⊕ The radius of is 1. 77 ^ +0. 09 -0. 08 R_⊕, the 3, and the 3. The third planet, _ upper mass limit is 4. 9, M_⊕ upper density limit is 0. 88, ̊ho_⊕ is Earth-sized with a radius of 0. 99 ^ +0. 07 -0. 06, R_⊕, a 3, and a 3. While upper mass limit of 2. 2, M_⊕ upper density limit of 2. 2, ̊ho_⊕ is most probably rocky, given its Earth-like radius, and are located in a highly degenerate region in the mass-radius space. appears to lean toward a water-world composition. has enough mass to host a significant H-He envelope, although a water-world and pure rocky compositions are also consistent with the data. Our analysis indicates that future atmospheric observations using JWST can aid in determining their real composition. The sample of small planets around M dwarfs is widely used to understand planet formation and composition theories, and our study adds three planets to this sample.
Poultourtzidis et al. (Tue,) studied this question.