Autor(es)

Araujo, Alexandre ; Valio, Adriana

• Tipo de documento: Artigo Científico
• Fonte: ASTROPHYSICAL JOURNAL; v. 956, n. 2, p. 6-pg., 2023-10-01.

Resumo

Stellar rotation is crucial for studying stellar evolution, since it provides information about age, angular momentum transfer, and magnetic fields of stars. In the case of the Sun, due to its proximity, detailed observation of sunspots at various latitudes and longitudes allows a precise estimation of the solar rotation period and its differential rotation. Here, we present for the first time an analysis of stellar differential rotation using starspot transit mapping as a means of detecting differential shear in solar-type and M stars. The aim of this study is to investigate the relationship between rotational shear, Delta Omega, and both the star's effective temperature (T-eff) and its average rotation period ((P) over bar). We present differential rotation profiles derived from previously collected spot transit mapping data for 13 slowly rotating stars (P-rot >= 4.5 days), with spectral types ranging from M to F, which were observed by the Kepler and CoRoT satellites. Our findings reveal a significant negative correlation between rotational shear and the mean period of stellar rotation (correlation coefficient of -0.77), which may be an indicator of stellar age. On the other hand, a weak correlation was observed between differential rotation and the effective temperature of the stars. Overall, the study provides valuable insights into the complex relationship between stellar parameters and differential rotation, which may enhance our understanding of stellar evolution and magnetic dynamos. (AU)

• Processo FAPESP: 18/04055-8 - Espectroscopia de alta precisão: das primeiras estrelas aos planetas
• Beneficiário: Jorge Luis Melendez Moreno
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 21/02120-0 - Investigação de fenômenos de astrofísica de plasmas e altas energias, instalação do ASTRI-Mini Array & construção dos telescópios de tamanho pequeno do Cherenkov Telescope Array (CTA-SSTs)
• Beneficiário: Elisabete Maria de Gouveia Dal Pino
• Modalidade de apoio: Auxílio à Pesquisa - Projetos Especiais