5 papers
Ba Isotope Ratio in CEMP-s and CEMP-rs Stars as a Signature of s-Process and i-Process
Tatyana Sitnova, Lyudmila Mashonkina
We present a spectroscopic analysis of three carbon-enhanced metal-poor (CEMP) stars of type CEMP-s and CEMP-rs and determine their non-local thermodynamic equilibrium (NLTE) abund…
No country for old stars -Spectroscopic confirmation of the first intermediate-age RR Lyrae in the open cluster Trumpler 5
Valentina D'Orazi, Cecilia Mateu, Giuliano Iorio +13
RR Lyrae stars are widely considered tracers of ancient (greater than 10 Gyr), metal-poor stellar populations. However, recent kinematic and photometric studies suggest the existen…
HD 188101: A Spotted B Star with Abundance Anomalies
R. M. Bayazitov, L. I. Mashonkina, Yu. V. Pakhomov +1
Based on spectroscopic and photometric observations, we have determined the fundamental parameters of the poorly studied star HD 188101 with a weak magnetic field. Its effective te…
Distinct barium isotope ratios in CEMP-s and CEMP-rs stars
T. M. Sitnova, L. I. Mashonkina, A. M. Romanovskaya +2
We present a spectroscopic analysis of ten carbon enhanced metal-poor (CEMP) stars of type CEMP-s and CEMP-rs and determine their NLTE abundances of Ba and Eu, as well as the fract…
Unlocking the mystery of Sr synthesis in the early Galaxy through analysis of barium isotopes in very metal-poor stars
T. M. Sitnova, L. Lombardo, L. I. Mashonkina +8
We determine the contributions of the rapid (r) and slow (s) neutron capture processes to the Ba isotope mixture, along with Ba, Eu, and Sr NLTE abundances, in a sample of very met…