2 papers
astro-ph.CO2026
Fifty years of primordial helium abundances: A statistical reanalysis
Nabil Husain, Richard de Grijs, Giuseppe Bono
The primordial helium mass fraction, , is a key observational pillar of Big Bang nucleosynthesis and a sensitive probe of early-Universe physics. Over the past severa…
astro-ph.GA2026
Spectroscopic metallicities and first α-element abundances of RR Lyrae stars in Baade's Window
J. Olivares Carvajal, Ã. Rojas-Arriagada, M. Zoccali +10
RR Lyrae stars in the bulge have been reported to be associated with the spheroidal, relatively metal-poor component. They offer a way to trace this component with precise distance…