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Stellar chronometers: the relation between age, chromospheric activity, rotation and lithium abundances in solar-type stars

Grant number: 16/20667-8
Support Opportunities:Scholarships in Brazil - Post-Doctorate
Effective date (Start): April 01, 2017
Effective date (End): August 31, 2021
Field of knowledge:Physical Sciences and Mathematics - Astronomy - Stellar Astrophysics
Acordo de Cooperação: Coordination of Improvement of Higher Education Personnel (CAPES)
Principal Investigator:Jorge Luis Melendez Moreno
Grantee:Diego Lorenzo de Oliveira
Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil
Associated research grant:18/04055-8 - High precision spectroscopy: from the first stars to planets, AP.TEM


Our main goal is to study the impact of stellar abundances and other atmospheric parameters on the determination of chromospheric activity levels traced by different spectroscopic indicators such as: Ca II & K, Na I dublet, Halpha, Hbeta and Ca II infrared triplet lines. This study will use chromospheric fluxes to obtain stellar ages through age-activity relations. As a result, we plan to: 1) characterize comprehensively the chromospheric activity phenomena, exploring the correlations between the chromospheric activity indicators (flux-flux relations); 2) investigate the relationship between the stellar activity level, stellar rotation and the convective mixing processes traced by lithium depletion in solar-type stars. To this end, we will derive chromospheric absolute fluxes based on modern theoretical models of stellar atmospheres Lorenzo-Oliveira et al. 2016 for a benchmark sample of 88 solar twins (Ramírez et al. 2014) with high-precision spectroscopic parameters(sigma(Teff) = 7 K, sigma([Fe/H]) = 0.01 dex and sigma(log g) = 0.02 dex). Moreover, in order to extend the relations derived for solar twins, we compiled high spectral resolution and signal-to-noise ratio spectra for a large ancillary sample of solar-type stars within a broad range of masses and metallicities. Precise atmospheric parameters (Teff, [Fe/H] and log g) will be determined for these stars in the light of detailed spectroscopic line-by-line analysis (excitation and ionisation equilibria of Fe I and Fe II lines) and evolutionary parameters will be estimated through HR diagrams. Our final goal is to provide the most reliable activity-age relations for age dating. (AU)

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Scientific publications (14)
(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)
GIRIBALDI, R. E.; UBALDO-MELO, M. L.; PORTO DE MELLO, G. F.; PASQUINI, L.; LUDWIG, H-G; ULMER-MOLL, S.; LORENZO-OLIVEIRA, D.. Accurate effective temperature from H alpha profiles. Astronomy & Astrophysics, v. 624, . (16/20667-8)
BARRAGAN, O.; GANDOLFI, D.; SMITH, A. M. S.; DEEG, H. J.; FRIDLUND, M. C. V.; PERSSON, C. M.; DONATI, P.; ENDL, M.; CSIZMADIA, SZ.; GRZIWA, S.; et al. K2-139 b: a low-mass warm Jupiter on a 29-d orbit transiting an active K0 V star. Monthly Notices of the Royal Astronomical Society, v. 475, n. 2, p. 1765-1776, . (16/20667-8)
GALARZA, JHON YANA; MELENDEZ, JORGE; LORENZO-OLIVEIRA, DIEGO; VALIO, ADRIANA; REGGIANI, HENRIQUE; CARLOS, MARILIA; PONTE, GEISA; SPINA, LORENZO; HAYWOOD, RAPHAELLE D.; GANDOLFI, DAVIDE. The effect of stellar activity on the spectroscopic stellar parameters of the young solar twin HIP 36515. Monthly Notices of the Royal Astronomical Society, v. 490, n. 1, p. L86-L90, . (16/20667-8, 18/04055-8)
LORENZO-OLIVEIRA, DIEGO; FREITAS, FABRICIO C.; MELENDEZ, JORGE; BEDELL, MEGAN; RAMIREZ, IVAN; BEAN, JACOB L.; ASPLUND, MARTIN; SPINA, LORENZO; DREIZLER, STEFAN; ALVES-BRITO, ALAN; et al. The Solar Twin Planet Search The age-chromospheric activity relation. Astronomy & Astrophysics, v. 619, . (12/24392-2, 16/20667-8)
GIRIBALDI, R. E.; DE MELLO, G. F. PORTO; LORENZO-OLIVEIRA, D.; AMORES, E. B.; UBALDO-MELO, M. L.. Faint solar analogues at the limit of no reddening Precise atmospheric parameters from moderate low-resolution spectra. Astronomy & Astrophysics, v. 629, . (16/20667-8)
NETTO, YURI; LORENZO-OLIVEIRA, DIEGO; MELENDEZ, JORGE; YANA GALARZA, JHON; HAYWOOD, RAPHAELLE D.; SPINA, LORENZO; DOS SANTOS, LEONARDO A.. Radial-velocity Precision of ESPRESSO Through the Analysis of the Solar Twin HIP 11915. ASTRONOMICAL JOURNAL, v. 162, n. 4, . (18/04055-8, 19/20319-8, 16/20667-8)
LORENZO-OLIVEIRA, DIEGO; MELENDEZ, JORGE; PONTE, GEISA; GALARZA, JHON YANA. The ancient main-sequence solar proxy HIP 102152 unveils the activity and rotational fate of our Sun. Monthly Notices of the Royal Astronomical Society, v. 495, n. 1, p. L61-L65, . (16/20667-8, 18/04055-8)
GRIEVES, N.; GE, J.; THOMAS, N.; WILLIS, K.; MA, B.; LORENZO-OLIVEIRA, D.; QUEIROZ, A. B. A.; GHEZZI, L.; CHIAPPINI, C.; ANDERS, F.; et al. Chemo-kinematics of the Milky Way from the SDSS-III MARVELS survey. Monthly Notices of the Royal Astronomical Society, v. 481, n. 3, p. 3244-3265, . (16/20667-8)
TUCCI MAIA, M.; MELENDEZ, J.; LORENZO-OLIVEIRA, D.; SPINA, L.; JOFRE, P.. Revisiting the 16 Cygni planet host at unprecedented precision and exploring automated tools for precise abundances. Astronomy & Astrophysics, v. 628, . (16/20667-8, 14/15706-9, 18/04055-8)
LORENZO-OLIVEIRA, DIEGO; MELENDEZ, JORGE; GALARZA, JHON YANA; PONTE, GEISA; DOS SANTOS, LEONARDO A.; SPINA, LORENZO; BEDELL, MEGAN; RAMIREZ, IVAN; BEAN, JACOB L.; ASPLUND, MARTIN. Constraining the evolution of stellar rotation using solar twins. Monthly Notices of the Royal Astronomical Society, v. 485, n. 1, p. L68-L72, . (18/04055-8, 16/20667-8)
COSTA-ALMEIDA, ELLEN; PORTO DE MELLO, GUSTAVO F.; GIRIBALDI, RIANO E.; LORENZO-OLIVEIRA, DIEGO; UBALDO-MELO, MARIA L.. dwarf spectral indices at moderate resolution: accurate T-eff and [Fe/H] for 178 southern star. Monthly Notices of the Royal Astronomical Society, v. 508, n. 4, p. 5148-5162, . (16/20667-8)
GALARZA, JHON YANA; MELENDEZ, JORGE; KARAKAS, I, AMANDA; ASPLUND, MARTIN; LORENZO-OLIVEIRA, DIEGO. Explosive nucleosynthesis of a metal-deficient star as the source of a distinct odd-even effect in the solar twin HIP 11915. Monthly Notices of the Royal Astronomical Society, v. 502, n. 1, p. L104-L109, . (16/20667-8)
GALARZA, JHON YANA; LOPEZ-VALDIVIA, RICARDO; LORENZO-OLIVEIRA, DIEGO; REGGIANI, HENRIQUE; MELENDEZ, JORGE; GAMARRA-SANCHEZ, DANIEL; FLORES, MATIAS; PORTAL-RIVERA, JERRY; MIQUELARENA, PAULA; PONTE, GEISA; et al. Searching for new solar twins: The Inti survey for the Northern Sky. Monthly Notices of the Royal Astronomical Society, v. 504, n. 2, p. 1873-1887, . (16/20667-8, 18/04055-8)
GALARZA, JHON YANA; LOPEZ-VALDIVIA, RICARDO; MELENDEZ, JORGE; LORENZO-OLIVEIRA, DIEGO. Evidence of Rocky Planet Engulfment in the Wide Binary System HIP 71726/HIP 71737. ASTROPHYSICAL JOURNAL, v. 922, n. 2, . (16/20667-8, 18/04055-8)

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