Results 31 to 40 of about 250,517 (293)

ACTINIUM ABUNDANCES IN STELLAR ATMOSPHERES

Odessa Astronomical Publications, 2021
This paper presents a study of radioactive  actinium in the atmospheres of stars located in galaxies with different chemical evolution history – namely, Przybylski's Star (HD 101065) in the Milky Way and the red supergiant PMMR27 in the Small Magellanic Cloud; it also reports the findings of the previous research of the red supergiant RM 1-667 in ...
V. Yushchenko, V. Gopka, A.V. Yushchenko, A. Shavrina, Ya. Pavlenkо, S. Vasil’eva   +5 more
openaire   +4 more sources

Stellar evolution with SMC chemical abundances [PDF]

International Astronomical Union Colloquium, 1981
Evolutionary computations are presented for massive stars between 20 Mo and 100 Mo with chemical abundances holding for the Small Magellanic Cloud, i.e. X = .76 and Z = .003. Mass loss by stellar wind is taken into account during core hydrogen burning.
P. Hellings, D. Vanbeveren
openaire   +1 more source

The Abundance of S-Process Elements: Temporal and Spatial Trends from Open Cluster Observations

Universe, 2022
Spectroscopic observations of stars belonging to open clusters, with well-determined ages and distances, are a unique tool for constraining stellar evolution, nucleosynthesis, mixing processes, and, ultimately, Galactic chemical evolution.
Laura Magrini, Carlos Viscasillas Vázquez, Giada Casali, Martina Baratella, Valentina D’Orazi, Lorenzo Spina, Sofia Randich, Sergio Cristallo, Diego Vescovi   +8 more
doaj   +1 more source

Stellar and Gaseous Abundances in M82

The Astrophysical Journal, 2004
The near infrared (IR) absorption spectra of starburst galaxies show several atomic and molecular lines from red supergiants which can be used to infer reliable stellar abundances. The metals locked in stars give a picture of the galaxy metallicity prior to the last burst of star formation. The enrichment of the new generation of stars born in the last
Origlia, L., Ranalli, P., Comastri, A., Maiolino, R.   +3 more
openaire   +2 more sources

THE IMPACT OF STELLAR ABUNDANCE VARIATIONS ON STELLAR HABITABLE ZONE EVOLUTION [PDF]

The Astrophysical Journal, 2012
The high quality spectra required for radial velocity planet searches are well-suited to providing abundances for a wide array of elements in large samples of stars. Abundance ratios of the most common elements relative to Fe are observed to vary by more than a factor of two in planet host candidates. This level of variation has a substantial impact on
Young, Patrick A., Liebst, Kelley, Pagano, Michael   +2 more
openaire   +2 more sources

The role of neutrinos in explosive nucleosynthesis in core collapse supernova models with neutrino transport [PDF]

, 2007
The problem of core collapse supernova explosions is long standing and attempts to understand the mechanism have been ongoing. On one hand, a full understanding of the underlying mechanism is still pending.
Fröhlich, Carla
core   +1 more source

Lithium in Turnoff Stars in the Globular Cluster M5: A Quest for Primordial Lithium

The Astrophysical Journal, 2023
The light element lithium is formed by nucleosynthesis during the Big Bang. Its abundance can help to define the parameters of the early Universe. To find this primordial value, it is necessary to determine Li abundances in the oldest stars because it is
Ann Merchant Boesgaard, Constantine P. Deliyannis   +1 more
doaj   +1 more source

THE SENSITIVITY OF CONVECTION ZONE DEPTH TO STELLAR ABUNDANCES: AN ABSOLUTE STELLAR ABUNDANCE SCALE FROM ASTEROSEISMOLOGY [PDF]

The Astrophysical Journal, 2012
The base of the convection zone is a source of acoustic glitches in the asteroseismic frequency spectra of solar-like oscillators, allowing one to precisely measure the acoustic depth to the feature. We examine the sensitivity of the depth of the convection zone to mass, stellar abundances, and input physics, and in particular, the use of a measurement
van Saders, Jennifer L., Pinsonneault, Marc H.   +1 more
openaire   +2 more sources

Disk evolution, element abundances and cloud properties of young gas giant planets [PDF]

, 2014
ChHc and PBR highlights financial support of the European Community under the FP7 program by an ERC starting grant. PW, IK, and WFT acknowledge funding from the European Union Seventh Framework Programme FP7-2011 under grant agreement No.
Kamp, I., Peter Woitke, Woitke, P., Meijerink, R., Helling, C., Inga Kamp, Christiane Helling, Wing-Fai Thi, Kamp, Inga, Meijerink, Rowin, Woitke, Peter, Kamp, Inga; id_orcid, Rimmer, Paul B., Rowin Meijerink, Rimmer, P.B., Paul B. Rimmer, Thi, W.-F., Thi, Wing-Fai, Helling, Christiane, Paul Rimmer   +19 more
core   +2 more sources

Stellar population gradients in galaxy discs from the CALIFA survey : the influence of bars [PDF]

, 2014
We acknowledge financial support from the research projects under grants AYA2010-21887-C04-03, AYA2010-21322-C03-03 and AYA2010-15081 by the Spanish Ministerio de Ciencia e Innovación.While studies of gas-phase metallicity gradients in disc galaxies are ...
Wisotzki, L., S. Zibetti, Márquez, I., D. Mast, Papaderos, P., R. García Benito, Rosales-Ortega, F.F., Sánchez, S. F., I. Pérez, Sánchez, S.F., J. Falcón-Barroso, Ruiz Lara, T., P. Sánchez-Blázquez, R. Cid Fernandes, L. Wisotzki, G. van de Ven, de Lorenzo Cáceres, A., P. Papaderos, C. Catalán-Torrecilla, M. Mollá, González Delgado, R., Mendoza, M. A., Aguerri, J.A.L., F. F. Rosales-Ortega, Mendez Abreu, Jairo, Ruiz-Lara, T., Cid Fernandes, R., A. de Lorenzo-Caceres, J. Méndez-Abreu, Zibetti, S., T. Ruiz-Lara, Mendoza, M.A., Iglesias Paramo, Jorge, B. Husemann, Sánchez Blázquez, Patricia, Falcón Barroso, J., Bland-Hawthorn, J., M. A. Mendoza, B. Jungwiert, Catalán Torrecilla, Cristina, Mollá, M., A. Galazzi, C. J. Walcher, A. Gil de Paz, Rosales Ortega, F. F., Mast, D., Marino, Raffaella Anna, Husemann, B., De Amorim, A., J. A. L. Aguerri, Aguerri, J. A. L., Gil De Paz, Armando, Marino, R.A., J. Bland-Hawthorn, A. de Amorim, Pérez, I., R. A. Marino, Walcher, C. J., Méndez Abreu, J., I. Márquez, Walcher, C.J., Galazzi, A., Iglesias-Páramo, J., Jungwiert, B., S. F. Sánchez, R. González Delgado, De Lorenzo-Caceres Rodriguez, Adriana, Catalán-Torrecilla, C., Gil De Paz, A., Van De Ven, G., Falcón-Barroso, J., García Benito, R., Sánchez-Blázquez, P., Jorge Iglesias-Páramo   +73 more
core   +1 more source