The GAPS Programme with HARPS-N at TNG

• Type: Article in International Scientific Journal
• Date: 2019

Authors

Barbato, D (Author) Other; Sozzetti, A (Author) Other; Biazzo, K (Author) Other; Malavolta, L (Author) Other; N.C. Santos (Author) FCUP; Damasso, M (Author) Other; Lanza, AF (Author) Other; Pinamonti, M (Author) Other; Affer, L (Author) Other; Benatti, S (Author) Other; Bignamini, A (Author) Other; Bonomo, AS (Author) Other; Borsa, F (Author) Other; Carleo, I (Author) Other; Claudi, R (Author) Other; Cosentino, R (Author) Other; Covino, E (Author) Other; Desidera, S (Author) Other; Esposito, M (Author) Other; Giacobbe, P (Author) Other; González-Álvarez, E (Author) Other; Gratton, R (Author) Other; Harutyunyan, A (Author) Other; Leto, G (Author) Other; Maggio, A (Author) Other; Maldonado, J (Author) Other; Mancini, L (Author) Other; Masiero, S (Author) Other; Micela, G (Author) Other; Molinari, E (Author) Other; Nascimbeni, V (Author) Other; Pagano, I (Author) Other; Piotto, G (Author) Other; Poretti, E (Author) Other; Rainer, M (Author) Other; Scandariato, G (Author) Other; Smareglia, R (Author) Other; Colombo, LS (Author) Other; Di Fabrizio, L (Author) Other; Faria, JP (Author) Other; Martinez Fiorenzano, A (Author) Other; Molinaro, M (Author) Other; Pedani, M (Author) Other

Journal

Title: Astronomy and Astrophysics

Vol. 621

Final page: A110

ISSN: 0004-6361

Publisher: EDP Sciences

Indexing

ISI Web of Knowledge - 7 Citations

Other information

Authenticus ID: P-00Q-CFJ

DOI: 10.1051/0004-6361/201834305

Abstract (EN): Context. Statistical studies of exoplanets have shown that giant planets are more commonly hosted by metal-rich dwarf stars than low-metallicity stars, while no such correlation is evident for lower mass planets. The search for giant planets around metal-poor stars and the estimate of their occurrence f(p) is an important element in providing support to models of planet formation. Aims. We present results from the HARPS-N search for giant planets orbiting metal-poor (-1.0 <= [Fe/H] <= -0.5 dex) stars in the northern hemisphere, complementing a previous HARPS survey on southern stars in order to update the estimate of f(p). Methods. High-precision HARPS-N observations of 42 metal-poor stars were used to search for planetary signals to be fitted using differential evolution Markov chain Monte Carlo single-Keplerian models. We then joined our detections to the results of the previous HARPS survey on 88 metal-poor stars to provide a preliminary estimate of the two-hemisphere f(p). Results. We report the detection of two new giant planets around HD 220197 and HD 233832. The first companion has Msin i = 0.20(-0.04)(+0.07) M-Jup and an orbital period of 1728(-80)(+162) days, and for the second companion, we find two solutions of equal statistical weight with periods of 2058(-40)(+47) and 4047(-117)(+91) days and minimum masses of 1.78(-0.06)(+0.08) and 2.72(-0.23)(+0.23) MJ(up), respectively. Joining our two detections with the three from the southern survey, we obtain a preliminary and conservative estimate of the global frequency of f(p) = 3.84(-1-06)(+2.45)% for giant planets around metal-poor stars. Conclusions. The two new giant planets orbit dwarf stars at the metal-rich end of the HARPS-N metal-poor sample. This corroborates previous results that suggested that giant planet frequency is still a rising function of the host star [Fe/H]. We also note that all detections in the overall sample are giant long-period planets.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12