COLOR–MAGNITUDE DIAGRAM CONSTRAINTS ON THE METALLICITIES, AGES, AND STAR FORMATION HISTORY OF THE STELLAR POPULATIONS IN THE CARINA DWARF SPHEROIDAL GALAXY

AbstractWe took advantage of the Gaia DR1 to combine TGAS parallaxes with Tycho-2 and APASS photometry to calculate the star formation history (SFH) of the solar neighbourhood within 250 pc using the colour-magnitude diagram fitting technique. We present the determination of the completeness within this volume, and compare the resulting SFH with that calculated from the Hipparcos catalogue within 80 pc of the Sun. We also show how this technique will be applied out to ~5 kpc thanks to the next Gaia data releases, which will allow us to quantify the SFH of the thin disc, thick disc and halo in situ, rather than extrapolating based on the stars from these components that are today in the solar neighbourhood.

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Dissecting the Formation Histories of Galaxies with Stellar Populations Models

Proceedings of the International Astronomical Union ◽

10.1017/s174392131000270x ◽

2009 ◽

Vol 5 (S262) ◽

pp. 153-163

Author(s):

Ivo Labbé

Keyword(s):

Star Formation ◽

Current Knowledge ◽

High Redshift ◽

Local Environment ◽

Stellar Populations ◽

Current Data ◽

Star Formation History ◽

Spectral Energy ◽

Formation History ◽

History Of

AbstractHow did galaxies evolve from primordial fluctuations to the well-ordered but diverse population of disk and elliptical galaxies that we observe today? Stellar populations synthesis models have become a crucial tool in addressing this question by helping us to interpret the spectral energy distributions of present-day galaxies and their high redshift progenitors in terms of fundamental characteristics such as stellar mass and age. I will review our current knowledge on the evolution of stellar populations in early- and late type galaxies at z < 1 and the tantalizing – but incomplete – view of the stellar populations in galaxies at 1 < z < 3, during the global peak of star formation. Despite great progress, many fundamental questions remain: what processes trigger episodes of galaxy-scale star formation and what quenches them? To what degree does the star formation history of galaxies depend on the merger history, (halo) mass, or local environment? I will discuss some of the challenges posed in interpreting current data and what improved results might be expected from new observational facilities in the near- and more distant future.

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The Star Formation History of Leo I

Symposium - International Astronomical Union ◽

10.1017/s0074180900204063 ◽

1999 ◽

Vol 192 ◽

pp. 151-157

Author(s):

C. Gallart ◽

W. L. Freedman

Keyword(s):

Star Formation ◽

Binary Stars ◽

Large Fraction ◽

Solar Neighborhood ◽

Star Formation History ◽

Formation History ◽

Magnitude Diagram ◽

History Of ◽

The One ◽

Low Rate

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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PIXEL COLOR MAGNITUDE DIAGRAMS FOR SEMI-RESOLVED STELLAR POPULATIONS: THE STAR FORMATION HISTORY OF REGIONS WITHIN THE DISK AND BULGE OF M31

The Astrophysical Journal ◽

10.3847/0004-637x/827/1/9 ◽

2016 ◽

Vol 827 (1) ◽

pp. 9 ◽

Cited By ~ 9

Author(s):

Charlie Conroy ◽

Pieter G. van Dokkum

Keyword(s):

Star Formation ◽

Stellar Populations ◽

Star Formation History ◽

Formation History ◽

History Of ◽

Pixel Color

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Reconstructing the star formation history of the Solar neighbourhood with Gaia

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317008341 ◽

2017 ◽

Vol 13 (S334) ◽

pp. 158-161

Author(s):

Edouard J. Bernard

Keyword(s):

Star Formation ◽

Star Formation Rate ◽

Formation Rate ◽

Star Formation History ◽

Solar Neighbourhood ◽

The Past ◽

Formation History ◽

Magnitude Diagram ◽

History Of

AbstractTaking advantage of the Gaia DR1, we combined TGAS parallaxes with the Tycho-2 and APASS photometry to calculate the star formation history (SFH) of the solar neighbourhood within 250 pc using the colour-magnitude diagram fitting technique. Our dynamically-evolved SFH is in excellent agreement with that calculated from the Hipparcos catalogue within 80 pc of the Sun, showing an enhanced star formation rate (SFR) in the past ~4 Gyr. We then correct the SFR for the disc thickening with age to obtain a SFR that is representative of the whole solar cylinder, and show that even with an extreme correction our results are not consistent with an exponentially decreasing SFR as found by recent studies. Finally, we discuss how this technique can be applied out to ~5 kpc thanks to the next Gaia data releases, which will allow us to quantify the SFH of the thin disc, thick disc and halo in situ.

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The star-formation history of the Universe from the stellar populations of nearby galaxies

Nature ◽

10.1038/nature02474 ◽

2004 ◽

Vol 428 (6983) ◽

pp. 625-627 ◽

Cited By ~ 346

Author(s):

Alan Heavens ◽

Benjamin Panter ◽

Raul Jimenez ◽

James Dunlop

Keyword(s):

Star Formation ◽

Stellar Populations ◽

Star Formation History ◽

Formation History ◽

History Of ◽

Nearby Galaxies ◽

The Universe

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Stellar Populations in High-z Galaxy Mergers

Symposium - International Astronomical Union ◽

10.1017/s0074180900112628 ◽

1999 ◽

Vol 186 ◽

pp. 202-202

Author(s):

Yasuhiro Shioya ◽

Kenji Bekki

Keyword(s):

Star Formation ◽

Chemical Evolution ◽

Stellar Populations ◽

Star Formation History ◽

Galaxy Mergers ◽

Formation History ◽

Self Consistent ◽

Consistent Manner ◽

History Of ◽

The Difference

We investigate the nature of stellar populations of major galaxy mergers between late-type spirals considerably abundant in interstellar medium by performing numerical simulations designed to solve both the dynamical and chemical evolution in a self-consistent manner. We particularly consider that the star formation history of galaxy mergers is a crucial determinant for the nature of stellar populations of merger remnants, and therefore investigate how the difference in star formation history between galaxy mergers affects the chemical evolution of galaxy mergers.

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