The SOPHIE search for northern extrasolar planets XIX. A system including a cold sub-Neptune potentially transiting a V=6.5 star HD 88986

被引：9

作者：

Heidari, N. ^{[1
,2
,3
,4
]}

Boisse, I. ^{[1
]}

Hara, N. C. ^{[5
]}

Wilson, T. G. ^{[6
]}

Kiefer, F. ^{[7
]}

Hebrard, G. ^{[2
,8
]}

Philipot, F. ^{[7
]}

Hoyer, S. ^{[1
]}

Stassun, K. G. ^{[9
]}

Henry, G. W. ^{[10
]}

Santos, N. C. ^{[11
,12
]}

Acuna, L. ^{[13
]}

Almasian, D. ^{[4
]}

Arnold, L. ^{[8
,14
]}

Astudillo-Defru, N. ^{[15
]}

Attia, O. ^{[5
]}

Bonfils, X. ^{[16
]}

Bouchy, F. ^{[5
]}

Bourrier, V. ^{[5
]}

Collet, B. ^{[1
]}

Cortes-Zuleta, P. ^{[1
]}

Carmona, A. ^{[16
]}

Delfosse, X. ^{[16
]}

Dalal, S. ^{[17
]}

Deleuil, M. ^{[1
]}

Demangeon, O. D. S. ^{[11
,12
]}

Diaz, R. F. ^{[20
,21
]}

Dumusque, X. ^{[5
]}

Ehrenreich, D. ^{[5
]}

Forveille, T. ^{[16
]}

Hobson, M. J. ^{[13
,19
]}

Jenkins, J. S. ^{[26
,33
]}

Jenkins, J. M. ^{[27
]}

Lagrange, A. M. ^{[7
]}

Latham, D. W. ^{[22
]}

Larue, P. ^{[16
]}

Liu, J. ^{[1
]}

Moutou, C. ^{[18
]}

Mignon, L. ^{[5
]}

Osborn, H. P. ^{[23
,24
,25
]}

Pepe, F. ^{[5
]}

Rapetti, D. ^{[27
,28
]}

Rodrigues, J. ^{[11
,12
,29
]}

Santerne, A. ^{[1
]}

Segransan, D. ^{[5
]}

Shporer, A. ^{[24
,25
]}

Sulis, S. ^{[1
]}

Torres, G. ^{[30
]}

Udry, S. ^{[5
]}

Vakili, F. ^{[3
]}

机构：

[1] Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France

[2] Univ Pierre & Marie Curie Paris VI, CNRS, UMR 7095, Inst Astrophys Paris, 98 Bis Blvd Arago, F-75014 Paris, France

[3] Univ Nice Sophia Antipolis UNS, CNRS, Observ Cote dAzur OCA, Lab JL Lagrange,UMR 7293, Campus Valrose, F-06108 Nice 2, France

[4] Shahid Beheshti Univ, Dept Phys, Tehran, Iran

[5] Univ Geneva, Observ Geneve, Chemin Pegasi 51, CH-1290 Sauverny, Switzerland

[6] Univ St Andrews, Sch Phys & Astron, SUPA, North Haugh KY16 9SS, Fife, Scotland

[7] Univ Paris, Univ PSL, Sorbonne Univ, LESIA,CNRS,Observ Paris, 5 Pl Jules Janssen, F-92195 Meudon, France

[8] Univ Aix Marseille, CNRS, Observ Haute Provence, F-04870 St Michel lObservatoire, France

[9] Vanderbilt Univ, Dept Phys & Astron, 6301 Stevenson Ctr Ln, Nashville, TN 37235 USA

[10] Tennessee State Univ, Ctr Excellence Informat Syst, 3500 John A Merritt Blvd,POB 9501, Nashville, TN 37209 USA

[11] Univ Porto, Inst Astrofis & Ciencias Espaco, CAUP, Rua Estrelas, PT-4150762 Porto, Portugal

[12] Univ Porto, Fac Ciencias, Dept Fis & Astron, Rua Campo Alegre, P-4169007 Porto, Portugal

[13] Max Planck Inst Astron, Heidelberg, Germany

[14] Canada France Hawaii Telescope Corp CFHT, 65-1238 Mamalahoa Hwy, Kamuela, HI 96743 USA

[15] Univ Catolica Santisima Concepcion, Dept Matemat & Fis Aplicadas, Alonso de Rivera 2850, Concepcion, Chile

[16] Univ Grenoble Alpes, CNRS, IPAG, F-38000 Grenoble, France

[17] Univ Exeter, Astrophys Grp, Exeter EX4 2QL, England

[18] Univ Toulouse, CNRS, IRAP, 14 Ave Belin, F-31400 Toulouse, France

[19] Millennium Inst Astrophys MAS, Nuncio Monsenor Sotero Sanz 100 Providencia, Santiago, Chile

[20] ECyT UNSAM, Int Ctr Adv Studies ICAS, CONICET, Campus Miguelete.25 Mayo & Francia, RA-1650 Buenos Aires, Argentina

[21] ECyT UNSAM, ICIFI CONICET, Campus Miguelete,25 Mayo & Francia, RA-1650 Buenos Aires, Argentina

[22] Harvard & Smithsonian, Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA

[23] Univ Bern, Phys Inst, Gesellsschaftstr 5, CH-3012 Bern, Switzerland

[24] MIT, Dept Phys, Cambridge, MA 02139 USA

[25] MIT, Kavli Inst Astrophys & Space Res, Cambridge, MA 02139 USA

[26] Univ Diego Portales, Inst Estudios Astrofis, Av Ejercito 441, Santiago, Chile

[27] NASA, Ames Res Ctr, Moffett Field, CA 94035 USA

[28] Univ Space Res Assoc, Res Inst Adv Comp Sci, Washington, DC 20024 USA

[29] Observ Francois Xavier Bagnoud OFXB, CH-3961 St Luc, Switzerland

[30] Harvard & Smithsonian, Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA

[31] Univ Paris Cite, F-75013 Paris, France

[32] Univ Paris Est Creteil, CNRS, LISA, F-75013 Paris, France

[33] Ctr Astrofis & Tecnol Afines CATA, Casilla 36-D, Santiago, Chile

[34] Univ Catolica Norte, Inst Astron, Angamos 0610, Antofagasta 1270709, Chile

来源：

ASTRONOMY & ASTROPHYSICS | 2024年 / 681卷

基金：

欧洲研究理事会; 英国科学技术设施理事会; 瑞士国家科学基金会;

关键词：

planets and satellites: detection; techniques: photometric; techniques: radial velocities; JUPITER-MASS COMPANION; RADIAL-VELOCITY; SUPER-EARTHS; TRANSMISSION SPECTROSCOPY; EQUILIBRIUM TEMPERATURE; MAGNETIC ACTIVITY; SPECTRAL-ANALYSIS; ERROR-CORRECTION; KEPLER STARS; SWEET-CAT;

D O I：

10.1051/0004-6361/202347897

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Transiting planets with orbital periods longer than 40 d are extremely rare among the 5000+ planets discovered so far. The lack of discoveries of this population poses a challenge to research into planetary demographics, formation, and evolution. Here, we present the detection and characterization of HD88986b, a potentially transiting sub-Neptune, possessing the longest orbital period among known transiting small planets (< 4 R-circle plus) with a precise mass measurement (sigma(M)/M > 25%). Additionally, we identified the presence of a massive companion in a wider orbit around HD88986. Our analysis reveals that HD88986b, based on two potential single transits on sector 21 and sector 48 which are both consistent with the predicted transit time from the RV model, is potentially transiting. The joint analysis of RV and photometric data show that HD88986b has a radius of 2.49 +/- 0.18 R-circle plus, a mass of 17.2(-3.8)(+4.0) M-circle plus, and it orbits every 146.05(-0.40)(+0.43) d around a subgiant HD88986 which is one of the closest and brightest exoplanet host stars (G2V type, R=1.543 +/- 0.065 R circle dot, V=6.47 +/- 0.01 mag, distance=33.37 +/- 0.04 pc). The nature of the outer, massive companion is still to be confirmed; a joint analysis of RVs, Hipparcos, and Gaia astrometric data shows that with a 3 sigma confidence interval, its semi-major axis is between 16.7 and 38.8 au and its mass is between 68 and 284 M-Jup. HD88986b's wide orbit suggests the planet did not undergo significant mass loss due to extreme-ultraviolet radiation from its host star. Therefore, it probably maintained its primordial composition, allowing us to probe its formation scenario. Furthermore, the cold nature of HD88986b (460 +/- 8 K), thanks to its long orbital period, will open up exciting opportunities for future studies of cold atmosphere composition characterization. Moreover, the existence of a massive companion alongside HD 88986 b makes this system an interesting case study for understanding planetary formation and evolution.

引用

页数：37