| Full text | |
| Author(s): |
dos Santos, Leonardo A.
[1, 2]
;
Melendez, Jorge
[1]
;
Bedell, Megan
[3]
;
Bean, Jacob L.
[3]
;
Spina, Lorenzo
[1]
;
Alves-Brito, Alan
[4]
;
Dreizler, Stefan
[5]
;
Ramirez, Ivan
[6]
;
Asplund, Martin
[7]
Total Authors: 9
|
| Affiliation: | [1] Univ Sao Paulo, Inst Astron, Geofis & Ciencias Atmosfer, Rua Matao 1226, BR-05508090 Sao Paulo - Brazil
[2] Observ Univ Geneve, 51 Chemin Maillettes, CH-1290 Versoix - Switzerland
[3] Univ Chicago, Dept Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 - USA
[4] Univ Fed Rio Grande do Sul, Inst Fis, Av Bento Goncalves 9500, BR-90650002 Porto Alegre, RS - Brazil
[5] Univ Gottingen, Inst Astrophys, D-37077 Gottingen - Germany
[6] Tacoma Community Coll, Washington, WA 98466 - USA
[7] Australian Natl Univ, Res Sch Astron & Astrophys, Cotter Rd, Weston, ACT 2611 - Australia
Total Affiliations: 7
|
| Document type: | Journal article |
| Source: | Monthly Notices of the Royal Astronomical Society; v. 472, n. 3, p. 3425-3436, DEC 2017. |
| Web of Science Citations: | 9 |
| Abstract | |
Previous studies on the rotation of Sun-like stars revealed that the rotational rates of young stars converge towards a well-defined evolution that follows a power-law decay. It seems, however, that some binary stars do not obey this relation, often by displaying enhanced rotational rates and activity. In the Solar Twin Planet Search program, we observed several solar twin binaries, and found a multiplicity fraction of 42 per cent similar to 6 per cent in the whole sample; moreover, at least three of these binaries (HIP 19911, HIP 67620 and HIP 103983) clearly exhibit the aforementioned anomalies. We investigated the configuration of the binaries in the program, and discovered new companions for HIP 6407, HIP 54582, HIP 62039 and HIP 30037, of which the latter is orbited by a 0.06 M-circle dot brown dwarf in a 1 m long orbit. We report the orbital parameters of the systems with well-sampled orbits and, in addition, the lower limits of parameters for the companions that only display a curvature in their radial velocities. For the linear trend binaries, we report an estimate of the masses of their companions when their observed separation is available, and a minimum mass otherwise. We conclude that solar twin binaries with low-mass stellar companions at moderate orbital periods do not display signs of a distinct rotational evolution when compared to single stars. We confirm that the three peculiar stars are double-lined binaries, and that their companions are polluting their spectra, which explains the observed anomalies. (AU) | |
| FAPESP's process: | 14/15706-9 - Differential abundances in solar-type stars: implications for planets formation and stellar nucleosynthesis |
| Grantee: | Lorenzo Spina |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 16/01684-9 - Revealing the orbits of solar twin binaries with enhanced rotation |
| Grantee: | Leonardo Augusto Gonçalves dos Santos |
| Support Opportunities: | Scholarships abroad - Research Internship - Master's degree |
| FAPESP's process: | 12/24392-2 - High precision spectroscopy: impact in the study of planets, stars, the galaxy and cosmology |
| Grantee: | Jorge Luis Melendez Moreno |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 14/26908-1 - How common is our sun in its period of rotation? |
| Grantee: | Leonardo Augusto Gonçalves dos Santos |
| Support Opportunities: | Scholarships in Brazil - Master |