English

Something new under the Sun: A magnetically driven CH/CN anti-correlation

Solar and Stellar Astrophysics 2026-08-03 v1

Abstract

Spectroscopic monitoring surveys have shown that the magnetic cycle alters the photospheric structure of the Sun, perturbing the formation of molecular lines. In parallel, the study of Globular Clusters has remained centred on the multiple stellar populations conundrum, a phenomenon defined-most notably-by the anti-correlation between CH and CN molecular bands, serving to distinguish between first-population and second-population stars. We systematically monitored the behaviour of the CH and CN molecular bands as a function of the solar magnetic cycle. We demonstrate that the disc-integrated solar spectrum exhibits a distinct CH/CN anti-correlation driven by the magnetic cycle. Our results suggest that the spectroscopic and photometric anomalies defining the multiple populations conundrum may be physically linked to a differential spectral response to varying degrees of surface magnetic coverage.

Cite

@article{arxiv.2608.02721,
  title  = {Something new under the Sun: A magnetically driven CH/CN anti-correlation},
  author = {Y. Momany and L. Monaco and S. Villanova and S. Zaggia and I. Saviane and L. Girardi and G. Volpato and G. Costa and N. R. Landin and I. Yegorova and M. Montalto and M. Dima and F. R. Herpich and F. Almeida-Fernandes},
  journal= {arXiv preprint arXiv:2608.02721},
  year   = {2026}
}

Comments

19 pages, 7 figures. A&A, in press. Abstract shortened for arXiv