Publication: Evidence of a massive planet candidate orbiting the young active K5V star BD+20 1790*,**
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2010-03
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Context. BD+20 1790 is a young active, metal-rich, late-type K5Ve star. We have undertaken a study of stellar activity and kinematics for this star over the past few years. Previous results show a high level of stellar activity, with the presence of prominence-like structures, spots on the surface, and strong flare events, despite the moderate rotational velocity of the star. In addition, radial velocity variations with a semi-amplitude of up to 1 km s(-1) were detected. Aims. We investigate the nature of these radial velocity variations, in order to determine whether they are due to stellar activity or the reflex motion of the star induced by a companion. Methods. We have analysed high-resolution echelle spectra by measuring stellar activity indicators and computing radial velocity (RV) and bisector velocity spans. Two-band photometry was also obtained to produce the light curve and determine the photometric period. Results. Based upon the analysis of the bisector velocity span, as well as spectroscopic indices of chromospheric indicators, Ca II H & K, H alpha, and taking the photometric analysis into account, we report that the best explanation for the RV variation is the presence of a substellar companion. The Keplerian fit of the RV data yields a solution for a close-in massive planet with an orbital period of 7.78 days. The presence of the close-in massive planet could also be an interpretation for the high level of stellar activity detected. Since the RV data are not part of a planet search programme, we can consider our results as a serendipitous evidence of a planetary companion. To date, this is the youngest main sequence star for which a planetary candidate has been reported.
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© ESO 2010. We thank Calar Alto Observatory for allocation of director’s discretionary time to this programme. This work was supported by the Spanish Ministerio de Educación y Ciencia (MEC) under grant AYA2005-02750, Ministerio de Ciencia e Innovación (MICINN) under grant AYA2008-06423-C03-03, and the Comunidad de Madrid under PRICIT project S-0505/ESP-0237 (ASTROCAM). M.C.G.O. acknowledges financial support from the European Commission in the form of a Marie Curie Intra European Fellowship (PIEF-GA- 2008-220679). M.H.O. and G.A.E. thank Dr. Chriss Moss, support astronomer at the LT for his help and patience. Also M.H.O. thanks Dr. Santos Pedraz, support astronomer at the Calar Alto Observatory for his help with DDT run. M.H.O. is grateful to Dr. José Antonio Caballero for valuable discussions, and also Dr. Laurence R. Doyle for his suggestions that was the initial inspiration for this work. This research has made use of the SIMBAD database, operated at CDS, Strasbourg, France. The authors gratefully acknowledge the valuable comments and suggestions of an anonymous referee that helped to improve the paper.
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Barden, S. C. 1985, ApJ, 295, 162
Barnes, J. R., Collier Cameron, A., James, D. J., & Donati, J.-F. 2000, MNRAS, 314, 162
Barnes, J. R., Cameron, A. C., Lister, T. A., et al. 2005, MNRAS, 356, 1501
Biazzo, K., Frasca, A., Henry, G. W., et al. 2007, ApJ, 656, 474
Bonfils, X., Mayor, M., Delfosse, X., et al. 2007, A&A, 474, 293
Bouvier, J., Alencar, S. H. P., Boutelier, T., et al. 2007, A&A, 463, 1017
Byrne, P. B., Eibe, M. T., & Rolleston, W. R. J. 1996, A&A, 311, 651
Cardiel, N. 1999, PhD Thesis, Universidad Complutense de Madrid
Carpenter, J. M., Bouwman, J., Silverstone, M. D., et al. 2008, ApJS, 179, 423
Carroll, B. W., & Ostlie, D. A. 2007, An Introduction to Modern Astrophysics, 2nd edn. (Pearson International Edition, Addison Wesley)
Catalano, S., Biazzo, K., Frasca, A., et al. 2002, A&A, 394, 1009
Collier Cameron, A. 1997, MNRAS, 287, 556
Collier Cameron, A. 2001, in Recent Insights into the Physics of the Sun and Heliosphere: Highlights from SOHO and Other Space Missions, IAU Symp., 203, 229
Collier Cameron, A., & Robinson, R. D. 1989a, MNRAS, 236, 57
Collier Cameron, A., & Robinson, R. D. 1989b, MNRAS, 238, 657
Collier Cameron, A., & Woods, J. A. 1992, MNRAS, 258, 360
Collier Cameron, A., Jardine, M. M., & Donati, J.-F. 2002, in Stellar Coronae in the Chandra and XMM-NEWTON Era, ASP Conf. Ser., 277, 397
Cumming, A. 2004, MNRAS, 354, 1165
Cuntz, M., & Shkolnik, E. 2002, 323, 387
Cuntz, M., Saar, S. H., & Musielak, Z. E. 2000, ApJ, 533, L151
Desort, M., Lagrange, A.-M., et al. 2007, A&A, 473, 983
Donati, J.-F., Mengel, M., Carter, B. D., et al. 2000, MNRAS, 316, 699
Eibe, M. T. 1998, A&A, 337, 757
Eibe, M. T., Byrne, P. B., Jeffries, R. D., et al. 1999, A&A, 341, 527
Esposito, M., Guenther, E., Hatzes, A. P., et al. 2006, Tenth Anniversary of 51 Peg-b: Status of and prospects for hot Jupiter studies, 127
Ferreira, J. M. 2000, MNRAS, 316, 647
Fischer, D. A., & Valenti, J. 2005, ApJ, 622, 1102
Fleming, T. A., Schmitt, J. H. M. M., & Giampapa, M. S. 1995, ApJ, 450, 401
Frasca, A., Biazzo, K., Catalano, S., et al. 2005, A&A, 432, 647
Gratton, R. G., Bonanno, G., Bruno, P., et al. 2001, Exp. Ast., 12, 107
González, G., Laws, C., Tyagi, S., et al. 2001, AJ, 121, 432
Guillot, T., Santos, N. C., Pont, F., et al. 2006, A&A, 453, L21
Hernán Obispo, M., de Castro, E., & Cornide, M. 2005, ESA SP, 560, 647
Hernán Obispo, M., de Castro, E., & Gálvez, M. C. 2007, Highlights of Spanish Astrophysics IV (Kluwer Academic Publishers)
Houdebine, E. R. 1992, Irish Astron. J., 20, 213
Huelamo, N., Figueira, P., Bonfils, X., et al. 2008, A&A, 489, L9
Huerta, M., Johns-Krull, C. M., Prato, L., et al. 2008, ApJ, 678, 472 Ip, W.-H., Kopp, A., & Hu, J.-H. 2004, ApJ, 602, L53
Jardine, M., & van Ballegooijen, A. A. 2005, MNRAS, 361, 1153
Jardine, M., Collier Cameron, A., Donati, J.-F., et al. 2001, MNRAS, 324, 201
Jeffries, R. D. 1995, MNRAS, 273, 559
Jeffries, R. D., & Jewell, S. J. 1993, MNRAS, 264, 106
Jeffries, R. D., Byrne, P. B., Doyle, J. G., et al. 1994, MNRAS, 270, 153
Kashyap, V. L., Drake, J. J., & Saar, S. H. 2008, ApJ, 687, 1339
Kurucz, R. L. 1993, Peculiar versus Normal Phenomena in A-type and Related Stars, IAU Colloq, 138, APCS, 44, 87
Kürster, M., Endl, M., Rouesnel, F., et al. 2003, A&A, 403, 1077
Lanza, A. F. 2008, A&A, 487, 1163
Lanza, A. F. 2009, A&A, 505, 339
López Santiago, J. 2005, PhD Thesis, Universidad Complutense de Madrid
López Santiago, J., Montes, D., Crespo Chacón, I., et al. 2006, ApJ, 643, 1160
Lowrance, P. J., Becklin, E. E., Schneider, G., et al. 2005, AJ, 130, 1845
Mamajek, E. E., & Hillenbrand, L. A. 2008, ApJ, 687, 1264
Mason, K. O., Hassall, B. J. M., Bromage, G. E., et al. 1995, MNRAS, 274, 1194
Martín, E. L., Guenther, E., Zapatero Osorio, M., et al. 2006, ApJ, 644, L75
Martínez Fiorenzano, A. F., Gratton, R. G., Desidera, S., et al. 2005, A&A, 442, 775
Mayor, M., & Queloz, D. 1995, Nature, 378, 355
Montes, D., de Castro, E., Fernández Figueroa, M. J., et al. 1995, A&AS, 114, 287
Norton, A. J., Wheatley, P. J., West, R. G., et al. 2007, A&A, 467, 785
Paulson, D. B., & Yelda, S. 2007, PASP, 118, 706
Paulson, D. B., Cochran, W. D., & Hatzes, A. P. 2004, AJ, 124, 3579
Pfeiffer, M. J., Frank, C., Baumueller, D., et al. 1998, A&AS, 130, 381
Prato, L., Huerta, M., Johns-Krull, C. M., et al. 2008, ApJ, 687, L103
Queloz, D., Henry, G. W., Sivan, J.P., et al. 2001, A&A, 379, 279
Reid, I. N., Cruz, K. L., Allen, P., et al. 2004, AJ, 128, 463
Rubenstein, E. P., & Schaefer, B. E. 2000, ApJ, 529, 1031
Saar, S. H. 2003, in Scientific Frontiers in Research on Extrasolar Planets, ASP Conf. Ser., 294, 65
Saar, S. H. 2009, AIP Conf. Ser., 1094, 152
Saar, S. H., & Donahue, R. A. 1997, ApJ, 485, 319
Saar, S. H., & Fischer, D. 2000, ApJ, 534, L105
Santos, N. C., Mayor, M., Naef, D., et al. 2000, A&A, 361, 265
Santos, N. C., Israelian, G., & Mayor, M. 2001, 373, 1019
Scargle, J. D. 1982, ApJ, 263, 835
Setiawan, J., Weise, P., Henning, T., et al. 2007, ApJ, 660, L145
Setiawan, J., Henning, T., Launhardt, R., et al. 2008, Nature, 451, 38
Sneden, C. 1973, ApJ, 184, 839
Steele, I. A., Smith, R. J., Rees, P. C., et al. 2005, SPIE Conf. Ser., 5489, 679
Tonry, J., & Davis, M. 1979, AJ, 84, 1511
Udry, S., & Santos, N. C. 2007, ARA&A, 45, 397
Walter, F. M. 1994, in Stellar Surface Structure, IAU Symp., 176, 355
Wu, Y., & Murray, N. 2003, ApJ, 589, 605