J/A+A/705/A243ivo://CDS.VizieR/J/A+A/705/A243CDSCharpentier P.Moutou C.Donati J.-F.Larue P.Delfosse X.,Cortes-Zuleta P.Ould-Elhkim M.Artigau E.Cadieux C.Hebrard G.,L'Heureux A.Carmona A.Debras F.Boisse I.Cook N.J.,the SPIRou science Consortium2026-03-02T06:25:50Z2026-01-23T19:35:49ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frradial-velocityspectroscopymagnetic-fieldsM dwarfs are prime targets in the search for exoplanets due to their prevalence and the enhanced radial velocity (RV) detectability of low-mass planets. Recent advancements in instrumentation have extended RV observations from the optical to the near-infrared (nIR) domain, enabling more effective study of M dwarfs, which are known to frequently host rocky planets. The nIR range offers increased RV sensitivity and potentially reduced stellar activity signals, making it particularly well-suited for these stars. We analyze spectropolarimetric data of the M4.5V star GJ 4274, acquired using the nIR spectropolarimeter SPIRou, in order to characterize its stellar activity and search for planetary signals. We additionally examine the TESS photometric data to search for transits corresponding to the potential signals in the RV data. In this study, the line-by-line framework is employed to derive the RV signal of GJ ,4274 acquired with SPIRou, and analyze it. From the SPIRou spectra, we also derive and analyze the longitudinal large scale magnetic field, B_ell_, and the surface temperature variations, dTemp. We combine the SPIRou RV data with some RV measurements from CARMENES, to model possible planetary signals with both circular and eccentric orbits. The activity is modeled with a Quasi-Periodic Gaussian Process. We also perform injection-recovery tests to the photometric TESS data to assess transit detectability. We report the discovery of two exoplanets around the nearby M dwarf star GJ 4274. Both planets are in a circular orbit with respective periods of Pb=1.6339+/-0.0001 and Pc=69.6^+0.3^_-1.1_d, this second period being located beyond the habitable zone. From their RV semi-amplitude signals (Kb=5.10^+0.70^_-0.67_m/s and Kc=4.11+/-0.64m/s), we derived their minimum masses that are respectively mbsini=2.97^+0.54^_-0.50_M_{Earth}_ and m_c_sini=8.4+/-1.3M_{Earth}_. TESS photometric observations rule out most transit scenarios, including the inner planet, yielding a maximum inclination for the planet b of $i_b \leq 83^{\circ}$. We do not detect RV variations related to stellar magnetic activity in the SPIRou time series, despite a prominent large-scale magnetic field of up to 206^+158^_-62_G of amplitude. We derive a rotation period for the star of 4.600^+0.011^_-0.006_d from the activity indicators. The two planets reported belong to the super-Earth/sub-Neptune class. GJ 4274 b has one of the shortest orbital periods among planets around <0.2M_{sun}_ M dwarfs within 15 pc, while GJ 4274 c lies in a sparsely populated region of the mass-period diagram. Their discovery adds to the census of nearby planetary systems and provides promising targets for future surveys.2026A&A...705A.243Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/705/A243CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/705/A243https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/705/A243http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/705/A243https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/705/A243https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/705/A243http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/705/A243GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/705/A243/rvSPIRou RV and wapiti componentsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDTime (BJD-240000)dtime.epochdoubleRVRadial velocitym/sphys.veloc;pos.heliocentricdoublee_RVError on RVm/sstat.errordoubleV1First wapiti componentstat.fit.paramdoubleV2Second wapiti componentstat.fit.paramdoubleV3Third wapiti componentstat.fit.paramdoubleBERVBarrycentique Earth radial velocitykm/sspect.dopplerVeloc;pos.earth;pos.eopdoubleJ/A+A/705/A243/dtempDifferential temperature time seriesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDTime (BJD-240000)dtime.epochdoubledtempDifferential temperatureKphys.temperaturedoublee_dtempError on dtempKstat.errordoubleJ/A+A/705/A243/blLongitudinal magnetic field time seriesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDTime (BJD-2459000)dtime.epochdoubleBlLongitudinal magnetic fieldGphys.magFieldfloate_BlError on BlGstat.errorfloat