A&A 563, A22 (2014) Astronomy DOI: 10.1051/0004-6361/201322067 & c ESO 2014 Astrophysics The SOPHIE search for northern extrasolar planets VI. Three new hot Jupiters in multi-planet extrasolar systems ,, C. Moutou1, G. Hébrard2,3, F. Bouchy1,4, L. Arnold3,N.C.Santos5,10, N. Astudillo-Defru6, I. Boisse5, X. Bonfils6, S. Borgniet6,X.Delfosse6,R.F.Díaz1,D.Ehrenreich4, T. Forveille6, J. Gregorio7,O.Labrevoir8, A.-M. Lagrange6, G. Montagnier3,2, M. Montalto5,F.Pepe4, J. Sahlmann4,A.Santerne5, D. Ségransan4,S.Udry4, and M. Vanhuysse9 1 Aix Marseille University, CNRS, LAM (Laboratoire d’Astrophysique de Marseille) UMR 7326, 13388 Marseille Cedex 13, France e-mail: [email protected] 2 Institut d’Astrophysique de Paris, UMR 7095 CNRS, Université Pierre & Marie Curie, 98bis boulevard Arago, 75014 Paris, France 3 Observatoire de Haute-Provence, CNRS & OAMP, 04870 Saint-Michel l’Observatoire, France 4 Observatoire de Genève, Université de Genève, 51 Chemin des Maillettes, 1290 Sauverny, Switzerland 5 Centro de Astrofísica, Universidade do Porto, rua das Estrelas, 4150-762 Porto, Portugal 6 UJF-Grenoble 1/CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG) UMR 5274, 38041 Grenoble, France 7 Atalaia group, Crow Observatory-Portalegre, Portugal 8 Centre d’Astronomie, Plateau du Moulin à Vent, 04870 Saint-Michel-l’Observatoire, France 9 Oversky, 47 Allée des Palanques, 33127 Saint Jean d’Illac, France 10 Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal Received 16 June 2013 / Accepted 9 October 2013 ABSTRACT We present high-precision radial-velocity measurements of three solar-type stars: HD 13908, HD 159243, and HIP 91258. The obser- vations were made with the SOPHIE spectrograph at the 1.93 m telescope of the Observatoire de Haute-Provence (France). They show that these three bright stars host exoplanetary systems composed of at least two companions. HD 13908 b is a planet with a minimum mass of 0.865 ± 0.035 MJup on a circular orbit with a period of 19.382 ± 0.006 days. There is an outer massive companion in the system with a period of 931 ± 17 days, e = 0.12 ± 0.02, and a minimum mass of 5.13 ± 0.25 MJup. The star HD 159243 also has two detected companions with respective masses, periods, and eccentricities of Mp= 1.13 ± 0.05 and 1.9 ± 0.13 MJup, P = 12.620 ± 0.004 and 248.4 ± 4.9 days, and e = 0.02 ± 0.02 and 0.075 ± 0.05. Finally, the star HIP 91258 has a planetary companion with a minimum mass of 1.068 ± 0.038 MJup, an orbital period of 5.0505 ± 0.0015 days, and a quadratic trend indicating an outer planetary or stellar companion that is as yet uncharacterized. The planet-hosting stars HD 13908, HD 159243, and HIP 91258 are main-sequence stars of spectral types F8V, G0V, and G5V, respectively, with moderate activity levels. HIP 91258 is slightly over-metallic, while the other two stars have solar-like metallicity. The three systems are discussed in the frame of formation and dynamical evolution models of systems composed of several giant planets. Key words. planets and satellites: detection – techniques: radial velocities – techniques: photometric – stars: individual: HD 13908 – stars: individual: HD 159243 – stars: individual: HIP 91258 1. Introduction Wright et al. (2012), indicating the frequency of stars that har- Radial-velocity surveys have continuously provided new extra- bour close-in massive planets – also called hot Jupiters: Mayor . ± . solar planetary candidates since 1995 (Mayor & Queloz 1995). et al. (2011) reported a value of 0 89 0 36% for the occur- rence of planets more massive than 50 M⊕ that have periods The observing strategy, consisting of multiple observations of single stars, is time-consuming and requires long-term pro- shorter than 11 days, Howard et al. (2010) found an occurrence . ± . M⊕ grams on quasi-dedicated telescopes. These observations are of 1 2 0 2% for planets more massive than 100 with pe- riods shorter than 12 days and Wright et al. (2012) estimated necessary, however, to achieve a complete picture of the exo- . ± . M⊕ planet population, especially towards the most populated long- 1 2 0 38% for planets more massive than 30 with periods Kepler ff period or/and low-mass ends. Statistical analyses were recently shorter than 10 days. In the survey, which has a di erent target sample, 0.43% of stars are found to harbour giant plan- published by Mayor et al. (2011), Howard et al. (2010), and ets with radii between 6 and 22 Earth radii and periods shorter than 10 days (Howard et al. 2012; Fressin et al. 2013). The fre- Tables 5–8 are available at the CDS via anonymous ftp to quency of planets then increases towards lower masses, to reach cdsarc.u-strasbg.fr (130.79.128.5)orvia more than 50% of the stars (Mayor et al. 2011) within the cur- http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/563/A22 rent detection limits of the available instruments. Hot Jupiters Tables 5–7 are also available in electronic form at http://www.aanda.org are thus extremely rare objects, although they have been at the heart of exoplanetary science for more than fifteen years, partic- Based on observations collected with the SOPHIE spectrograph on the 1.93 m telescope at the Observatoire de Haute-Provence (CNRS), ularly for detailed characterizations, such as atmospheric studies France, by the SOPHIE RPE Consortium (program PNP.CONS). and observations. Article published by EDP Sciences A22, page 1 of 11 A&A 563, A22 (2014) In this paper, we report the discovery of three new plan- Table 1. Observed and inferred stellar parameters for the planet-hosting ets with orbital periods shorter than 20 days and projected stars. masses of about one Jupiter mass. Interestingly, they are the inner planets in a multiple system, with a more massive sec- Parameter HD 13908 HD 159243 HIP 91258 ond companion in the external part of the system. These dis- Sp F8V G0V G5V coveries were made in the context of a large program with V [mag] 7.51 (0.01) 8.65 (0.01) 8.65 (0.01) B − V [mag] 0.53 0.54 0.80 SOPHIE, the high-precision radial-velocity spectrograph at the π [mas] 14.05 (0.70) 14.45 (1.14) 22.26 (0.66) Observatoire de Haute-Provence. The survey for giant planets d [pc] 71.2 (3.5) 69.2 (5.5) 44.9 (1.3) occupies about 12% of the telescope time since 2006 and has al- MV [mag] 3.25 4.45 5.39 ready allowed the discovery of twelve companions in the planet B.C. [mag] –0.016 –0.030 –0.134 or brown dwarf range (da Silva et al. 2007; Santos et al. 2008; L [L] 4.0 1.3 0.6 Teff [K] 6255 (66) 6123 (65) 5519 (70) Bouchy et al. 2009; Hébrard et al. 2010; Boisse et al. 2010; Díaz log g [cgs] 4.11 (0.11) 4.55 (0.11) 4.53 (0.12) et al. 2012). In Sect. 2, we describe the observations and analy- [Fe/H] [dex] 0.01 (0.04) 0.05 (0.04) 0.23 (0.05) ses, in Sect. 3 we report the stellar properties, and in Sect. 4 we M∗ [M] 1.29 (0.04) 1.125 (0.03) 0.95 (0.03) − show and analyse the radial-velocity observations. In Sect. 5,we v sin i [km s 1] 4.2 (0.5) 3.8 (0.5) 3.5 (0.5) log R –4.9 (0.2) –4.65 (0.1) –4.65 (0.1) discuss the results and conclude. HK Age [Gy] 2.9 (0.4) 1.25 (1.1) 2.4 (2.4) R∗ [R] 1.67 (0.1) 1.12 (0.05) 1.0 (0.04) 2. Spectroscopic observations Notes. Uncertainties are noted between parentheses. The horizontal line separates the parameters given in van Leeuwen (2007) from the The spectroscopic observations were obtained with the SOPHIE parameters derived in this paper. spectrograph at the Observatoire de Haute-Provence with the 1.93 m telescope in the framework of the large pro- gram (PNP.CONS) led by the SOPHIE Exoplanet Consortium, and Sousa et al. (2008) was used on the mean high-signal-to- presented in detail by Bouchy et al. (2009). The SOPHIE in- noise-ratio spectrum obtained for each star. We derived the ef- strument (Perruchot et al. 2011) is a fiber-fed environmen- fective temperature T ff, gravity log g, and the iron content of the tally stabilized echelle spectrograph covering the visible range e stellar atmospheres of HD 13908, HD 159243, and HIP 91258 from 387 to 694 nm. The spectral resolving power is 75 000 in using equivalent width measurements of the Fe I and Fe II weak high-resolution mode. lines by imposing excitation and ionization equilibrium assum- The radial velocities (RV) are obtained by cross-correlating ing local thermal equilibrium. Errors were obtained by quadrat- the extracted spectra with a numerical mask based on stel- ically adding respectively 60 K, 0.1, and 0.04 dex to the internal lar spectra, following the method developed by Baranne et al. errors on T ff,logg,and[Fe/H]. (1996)andPepe et al. (2002). For all three stars the numerical e The new reduction of the Hipparcos data (van Leeuwen mask corresponding to a G2 spectral type was used because it 2007) was used to obtain the stellar parallaxes and derive the provides the smallest individual error bars and residual scatter stellar luminosities after including the bolometric corrections compared with the other available F0 and K5 masks.