Results 11 to 20 of about 4,406,721 (399)

Evolutionary origin of power-laws in Biochemical Reaction Network; embedding abundance distribution into topology [PDF]

, 2005
The evolutionary origin of universal statistics in biochemical reaction network is studied, to explain the power-law distribution of reaction links and the power-law distributions of chemical abundances. Using cell models with catalytic reaction network, we find evidence that the power-law distribution in abundances of chemicals emerges by the ...
Chikara Furusawa, H. R. Ueda, Kunihiko Kaneko, V. A. Kuznetsov   +3 more
arxiv   +3 more sources

The effect of rotation on the abundances of the chemical elements of the A-type stars in the Praesepe cluster [PDF]

, 2008
We study how chemical abundances of late B-, A- and early F-type stars evolve with time, and we search for correlations between the abundance of chemical elements and other stellar parameters, such as effective temperature and Vsini. We have observed a large number of B-, A- and F-type stars belonging to open clusters of different ages.
Abt, Abt, Adelman, Ahumada, An, Bagnulo, Balona, Baumgardt, Burkhart, Burkhart, Canuto, Charbonneau, Chen, Clampitt, Conti, Dias, Fossati, G. Wade, Girardi, Glebocki, González-Garcá, Hartkopf, Hauck, Hill, J. Landstreet, Kharchenko, Kunzli, Kupka, L. Fossati, Landstreet, Landstreet, M. Gebran, Madsen, Mason, McAlister, Mermilliod, Napiwotzki, O. Kochukhov, Pace, Piskunov, Pourbaix, R. Monier, Renson, Richer, Robichon, Rodríguez, Royer, Ryabchikova, Ryabchikova, S. Bagnulo, Savanov, Shulyak, Sills, Talon, Tassoul, van Leeuwen, W. Weiss   +56 more
arxiv   +4 more sources

Origin of cosmic chemical abundances [PDF]

Monthly Notices of the Royal Astronomical Society, 2015
Cosmological N-body hydrodynamic computations following atomic and molecular chemistry (e$^-$, H, H$^+$, H$^-$, He, He$^+$, He$^{++}$, D, D$^+$, H$_2$, H$_2^+$, HD, HeH$^+$), gas cooling, star formation and production of heavy elements (C, N, O, Ne, Mg ...
U. Maio, E. Tescari
semanticscholar   +5 more sources

On the influence of the environment on galactic chemical abundances [PDF]

Monthly Notices of the Royal Astronomical Society, 2017
We examine the influence of the environment on the chemical abundances of late-type galaxies with masses of 10(9.1)-10(11) M-circle dot using data from the Sloan Digital Sky Survey.
L. Pilyugin, E. Grebel, I. Zinchenko, Y. Nefedyev, L. Mattsson   +4 more
semanticscholar   +6 more sources

Chemical Abundances of the S star GZ Peg [PDF]

Publications of the Astronomical Society of Australia, 2009
The chemical compositions of stars from the Asymptotic Giant Branch are still poorly known due to the low temperatures of their atmospheres and therefore the presence of many molecular transitions hampering the analysis of atomic lines.
Allen, Alonso, Goriely, Gustafsson, Jorissen, L. Pompéia, Lebzelter, Smiljanic, Woolf   +8 more
core   +3 more sources

Chemical Abundances of Planetary Nebulae in M33 [PDF]

Astronomy & Astrophysics, 2004
Using spectroscopic data presented in Magrini et al. (2003), we have analyzed with the photoionization code CLOUDY 94.00 (Ferland et al. 1998) 11 Planetary Nebulae belonging to the spiral galaxy M 33. Central star temperatures and nebular parameters have
A. Mampaso, Ambartsumian, Armsdorfer, Che, Corradi, Costa, Dufour, Exter, Ferland, Gurzadyan, Henry, Howard, Iben, Jacoby, Jacoby, Jacoby, Kingsburgh, L. Magrini, Leisy, M. Perinotto, Magrini, Mampaso, Maran, Morisset, Peimbert, Perinotto, Phillips, R. L. M. Corradi, Rauch, Richer, Stasinska, Vílchez, Walsh, Walsh   +33 more
core   +4 more sources

JINAbase: A database for chemical abundances of metal-poor stars [PDF]

Astrophysical Journal Supplement Series, 2017
Reconstructing the chemical evolution of the Milky Way is crucial for understanding the formation of stars, planets, and galaxies throughout cosmic time. Different studies associated with element production in the early universe and how elements are incorporated into gas and stars are necessary to piece together how the elements evolved.
Abdu Abohalima, A. Frebel
arxiv   +3 more sources

Chemical Abundances for 25 JWST Exoplanet Host Stars with KeckSpec [PDF]

Research Notes of the AAS, 2022
Using a data-driven machine learning tool we report T eff, log(g) , vsin(i) , and elemental abundances for 15 elements (C, N, O, Na, Mg, Al, Si, Ca, Ti, V, Cr, Mn, Fe, Ni, Y) for a sample of 25 exoplanet host stars targeted by JWST's first year of ...
A. Polanski, I. Crossfield, A. Howard, H. Isaacson, M. Rice   +4 more
semanticscholar   +1 more source

Detailed Chemical Abundances for a Benchmark Sample of M Dwarfs from the APOGEE Survey [PDF]

Astrophysical Journal, 2022
Individual chemical abundances for 14 elements (C, O, Na, Mg, Al, Si, K, Ca, Ti, V, Cr, Mn, Fe, and Ni) are derived for a sample of M dwarfs using high-resolution, near-infrared H-band spectra from the Sloan Digital Sky Survey-IV/Apache Point Observatory
D. Souto, K. Cunha, V. Smith, C. Prieto, K. Covey, D. A. García-Hernández, J. Holtzman, H. Jönsson, S. Mahadevan, S. Majewski, T. Masseron, M. Pinsonneault, D. Schneider, M. Shetrone, K. Stassun, R. Terrien, O. Zamora, G. Stringfellow, R. Lane, C. Nitschelm, B. Rojas-Ayala   +20 more
semanticscholar   +1 more source

Detailed Chemical Abundances of Stars in the Outskirts of the Tucana II Ultrafaint Dwarf Galaxy [PDF]

Astronomical Journal, 2022
We present chemical abundances and velocities of five stars between 0.3 and 1.1 kpc from the center of the Tucana II ultrafaint dwarf galaxy (UFD) from high-resolution Magellan/MIKE spectroscopy. We find that every star is deficient in metals (−3.6 < [Fe/
A. Chiti, A. Frebel, A. Ji, Mohammad K. Mardini, X. Ou, J. Simon, H. Jerjen, Dongwon Kim, J. Norris   +8 more
semanticscholar   +1 more source