Star Formation History in the Solar Neighborhood: The Link Between Stars and Cosmology

We advance some results of our study of the star formation history of the Local Group dSph galaxy Leo I, obtained through the analysis of its deep HST color-magnitude diagram (CMD) using model CMDs computed from stellar evolutionary models. We conclude that most star formation (≃ 90%) took place in Leo I between 7 and 1 Gyr ago. It seems to have started at a very low rate ≃ 15 Gyr ago and continued, also at a very low rate, from 1 Gyr ago until the present time. A constant Z=0.0004 and a large fraction of binary stars are required to obtain the best agreement with both the distribution of stars across the CMD and with its morphology. An IMF like the one obtained by Kroupa et al. (1993) for the solar neighborhood, or steeper, is compatible with the data.

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Evolution of spiral galaxies. 2: The star formation history in the solar neighborhood

The Astrophysical Journal ◽

10.1086/173666 ◽

1994 ◽

Vol 421 ◽

pp. 491 ◽

Cited By ~ 12

Author(s):

Maria Chiara Pardi ◽

Federico Ferrini

Keyword(s):

Star Formation ◽

Spiral Galaxies ◽

Solar Neighborhood ◽

Star Formation History ◽

Formation History

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Two distinct halo populations in the solar neighborhood: evidence from stellar abundance of beryllium

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313006248 ◽

2013 ◽

Vol 9 (S298) ◽

pp. 83-85

Author(s):

Kefeng Tan ◽

Gang Zhao

Keyword(s):

Star Formation ◽

Galactic Halo ◽

Formation Rate ◽

Solar Neighborhood ◽

Elemental Abundance ◽

Star Formation History ◽

Dwarf Stars ◽

Formation History ◽

The Galaxy ◽

History Of

AbstractIt is now generally believed that the Galaxy was formed through hierarchical merging, which means that different components of the Galaxy may have experienced different chemical evolution histories. Since alpha elements are mainly produced by core collapse supernovae, they are closely associated with the star formation history of the Galaxy. In this regard, Galactic components with different alpha elemental abundance patterns may show different behaviors in beryllium abundances since the production of beryllium is correlated with the cosmic rays and thus the supernovae. A recent study by Nissen & Schuster (2010) has revealed the existence of two distinct halo populations in the solar neighborhood based on the alpha elemental abundances and kinematics of 94 dwarf stars. We determined beryllium abundances for some of these stars and find systematic differences in beryllium abundances between these two halo populations. Our results consolidate the conclusion of two distinct halo populations in the solar neighborhood. Our results also show that beryllium abundance is a very good indicator of star formation rate, and could be used to trace the substructures of the Galactic halo.

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The Star Formation History in the Solar Neighborhood as Told by Massive White Dwarfs

The Astrophysical Journal ◽

10.3847/2041-8213/ab238e ◽

2019 ◽

Vol 878 (1) ◽

pp. L11 ◽

Cited By ~ 8

Author(s):

Jordi Isern

Keyword(s):

Star Formation ◽

White Dwarfs ◽

Solar Neighborhood ◽

Star Formation History ◽

Formation History

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The Star Formation History and IMF in the LMC and SMC from Deep HST Imaging

Symposium - International Astronomical Union ◽

10.1017/s0074180900118200 ◽

1999 ◽

Vol 190 ◽

pp. 351-353

Author(s):

J. Holtzman ◽

J. R. Mould ◽

J. S. Gallagher

Keyword(s):

Star Formation ◽

Mass Function ◽

Initial Mass Function ◽

Solar Neighborhood ◽

Star Formation History ◽

Initial Mass ◽

Luminosity Functions ◽

Formation History

We present deep photometry to V ~ 27.5 obtained with the HST in several fields in the LMC and the SMC. We derive luminosity functions for the faintest stars which are consistent with an initial mass function similar to that of the solar neighborhood, although moderate variations are not excluded. We discuss implications of these observations for the star formation history in these regions of the LMC and SMC.

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