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The KESPRINT consortium identified K2-216 as a planetary candidate host star in the K2 space mission Campaign 8 field with a transiting super-Earth. The planet has recently been validated as well. Our aim was to confirm the detection and derive the main physical characteristics of K2-216b, including the mass. We performed a series of follow-up observations: high resolution imaging with the FastCam camera at the TCS, the Infrared Camera and Spectrograph at Subaru, and high resolution spectroscopy with HARPS (ESO, La Silla), HARPS-N (TNG), and FIES (NOT). The stellar spectra were analyzed with the SpecMatch-Emp and SME codes to derive the stellar fundamental properties. We analyzed the K2 light curve with the Pyaneti software. The radial-velocity measurements were modelled with both a Gaussian process (GP) regression and the floating chunk offset (FCO) technique to simultaneously model the planetary signal and correlated noise associated with stellar activity. Imaging confirms that K2-216 is a single star. Our analysis discloses that the star is a moderately active K5V star of mass 0.70+/-0.03 Msun and radius 0.72+/-0.03 Rsun. Planet b is found to have a radius of 1.75+0.17-0.10 Rearth and a 2.17-day orbit in agreement with previous results. We find consistent results for the planet mass from both models: 7.4+/-2.2 Mearth from the GP regression, and 8.0+/-1.6 Mearth from the FCO technique, which implies that this planet is a super-Earth. The planet parameters put planet b in the middle of, or just below, the gap of the radius distribution of small planets. The density is consistent with a rocky composition of primarily iron and magnesium silicate. In agreement with theoretical predictions, we find that the planet is a remnant core, stripped of its atmosphere, and is one of the largest planets found that has lost its atmosphere.
K2-291 (EPIC 247418783) is a solar-type star with a radius of R_star = 0.899 $pm$ 0.034 R_sun and mass of M_star=0.934 $pm$ 0.038 M_sun. From K2 C13 data, we found one super-Earth planet (R_p = 1.589+0.095-0.072 R_Earth) transiting this star on a sho
The interaction between Earth-like exoplanets and the magnetic field of low-mass host stars are considered to produce weak emission signals at radio frequencies. A study using LOFAR data announced the detection of radio emission from the mid M-type d
HD3167 is a bright (V=8.9 mag) K0V star observed by the NASAs K2 space mission during its Campaign 8. It has been recently found to host two small transiting planets, namely, HD3167b, an ultra short period (0.96 d) super-Earth, and HD3167c, a mini-Ne
M-dwarfs have proven to be ideal targets for planetary radial velocity (RV) searches due to their higher planet-star mass contrast. The HADES and CARMENES programs aim to carry out extensive searches of exoplanetary systems around this type of stars
We report the discovery of the 1.008-day, ultra-short period (USP) super-Earth HD 213885b (TOI-141b) orbiting the bright ($V=7.9$) star HD 213885 (TOI-141, TIC 403224672), detected using photometry from the recently launched TESS mission. Using FEROS