| Full text | |
| Author(s): |
Ponte, Geisa
;
Lorenzo-Oliveira, Diego
;
Melendez, Jorge
;
Yana Galarza, Jhon
;
Valio, Adriana
Total Authors: 5
|
| Document type: | Journal article |
| Source: | Monthly Notices of the Royal Astronomical Society; v. 522, n. 2, p. 8-pg., 2023-04-21. |
| Abstract | |
Stellar ages are elusive to measure, albeit being very important for understanding stellar evolution. We investigate the impact of photospheric activity on 2-min cadence light curves from the TESS/NASA mission of a selected sample of 30 solar-twins with well-determined ages. The photometric variability, A(T ESS), of the light curves due to rotational modulations by the presence of activ e re gions was estimated and correlated with chromospheric activity (Ca II H&K lines from an e xtensiv e High Accurac y Radial velocity Planet Searcher (HARPS) at the European Southern Observ atory (ESO) HARPS/ESO acti vity time series) and ages. Moreo v er, these results were compared with the total solar irradiance amplitude behaviour during the solar magnetic cycles 23 and 24, validating our findings for solar-twins. Our results show the photometric amplitude to be strongly correlated to the av erage lev el of chromospheric activity for the star sample. Also, we found a good correlation of A(T ESS) with stellar age (in Gyr) described by log t = + 12 . 239 - 0 . 894 log A(T ESS). In conclusion, stellar photometric variability A(T ESS )may be used as a simple age diagnostic for solar-twins. (AU) | |
| FAPESP's process: | 18/04055-8 - High precision spectroscopy: from the first stars to planets |
| Grantee: | Jorge Luis Melendez Moreno |
| Support Opportunities: | Research Projects - Thematic Grants |
| FAPESP's process: | 16/20667-8 - Stellar chronometers: the relation between age, chromospheric activity, rotation and lithium abundances in solar-type stars |
| Grantee: | Diego Lorenzo de Oliveira |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |