Inhomogeneous Chemical Evolution of the Galaxy in the Solar Neighbourhood

被引:7
作者
Sahijpal, S. [1 ]
机构
[1] Panjab Univ, Dept Phys, Chandigarh 160014, India
关键词
Galaxy evolution; stellar nucleosynthesis; chemical evolution; elemental abundances of dwarf stars; solar abundance; supernova; METAL-POOR STARS; EXTREME HALO STARS; GALACTIC DISK; OXYGEN ABUNDANCES; NITROGEN ABUNDANCES; INTERSTELLAR-MEDIUM; IA SUPERNOVAE; DWARF STARS; CARBON; ELEMENTS;
D O I
10.1007/s12036-013-9188-2
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
N-body numerical simulations of an inhomogeneous Galactic Chemical Evolution (GCE) of the solar neighbourhood with a high temporal resolution are presented. The solar annular ring is divided into distinct spatial grids of area similar to 1-2 kpc(2). Each grid evolves distinctly in terms of star formation and nucleosynthetic yields from numerous generations of stars. The evolution of the galaxy is simulated by considering discrete episodes of star formation. Subsequent to the evolution of the simulated stars within each grid the stellar nucleosynthetic yields are homogenized within the grid rather than the traditionally adopted criteria of homogenizing over the entire solar annular ring. This provides a natural mechanism of generating heterogeneities in the elemental abundance distribution of stars. A complex chemical evolutionary history is inferred that registers episodes of time-dependent contributions from SN II+Ib/c with respect to SN Ia. It was observed that heterogeneities can remerge even after episodes of large scale homogenizations on scales larger than the grid size. However, a comparison of the deduced heterogeneities with the observed scatter in the elemental abundances of the dwarf stars suggest only a partial match, specifically, for [Fe/H] > -0.5. The deduced heterogeneities in the case of carbon, oxygen, magnesium, silicon, sulphur, calcium and titanium can explain the observed heterogeneities for [Fe/H] < -0.5. It may not be possible to explain the entire observed spread exclusively on the basis of the inhomogeneous GCE.
引用
收藏
页码:297 / 316
页数:20
相关论文
共 65 条
  • [1] Galactic chemical abundance evolution in the solar neighborhood up to the iron peak
    Alibés, A
    Labay, J
    Canal, R
    [J]. ASTRONOMY & ASTROPHYSICS, 2001, 370 (03): : 1103 - 1121
  • [2] Argast D, 2000, ASTRON ASTROPHYS, V356, P873
  • [3] The Chemical Composition of the Sun
    Asplund, Martin
    Grevesse, Nicolas
    Sauval, A. Jacques
    Scott, Pat
    [J]. ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS, VOL 47, 2009, 47 : 481 - 522
  • [4] BARBUY B, 1989, ASTRON ASTROPHYS, V214, P239
  • [5] The origin and chemical evolution of carbon in the Galactic thin and thick discs
    Bensby, T
    Feltzing, S
    [J]. MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2006, 367 (03) : 1181 - 1193
  • [6] Oxygen in unevolved metal-poor stars from Keck ultraviolet hires spectra
    Boesgaard, AM
    King, JR
    Deliyannis, CP
    Vogt, SS
    [J]. ASTRONOMICAL JOURNAL, 1999, 117 (01) : 492 - 507
  • [7] A comparison of the chemical evolutionary histories of the galactic thin disk and thick disk stellar populations
    Brewer, MM
    Carney, BW
    [J]. ASTRONOMICAL JOURNAL, 2006, 131 (01) : 431 - 454
  • [8] CARBON AND NITROGEN ABUNDANCES IN METAL-POOR DWARFS OF THE SOLAR NEIGHBORHOOD
    CARBON, DF
    BARBUY, B
    KRAFT, RP
    FRIEL, ED
    SUNTZEFF, NB
    [J]. PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC, 1987, 99 (615) : 335 - 368
  • [9] Carretta E, 2000, ASTRON ASTROPHYS, V356, P238
  • [10] First stars V -: Abundance patterns from C to Zn and supernova yields in the early Galaxy
    Cayrel, R
    Depagne, E
    Spite, M
    Hill, V
    Spite, F
    François, P
    Plez, B
    Beers, T
    Primas, F
    Andersen, J
    Barbuy, B
    Bonifacio, P
    Molaro, P
    Nordström, B
    [J]. ASTRONOMY & ASTROPHYSICS, 2004, 416 (03) : 1117 - 1138