c. morossi , m . franchini , p . di marcantonio

INAF – Osservatorio Astronomico di Trieste INAF – Osservatorio Astronomico di Trieste C. MorossiC. MorossiINAF – Osservatorio Astronomico di Trieste INAF – Osservatorio Astronomico di Trieste C. MorossiC. Morossi

Chemical evolution in the Universe: the next 30 years Chemical evolution in the Universe: the next 30 years 16-20 Sept, 2013 Castiglione della Pescaia, Italy16-20 Sept, 2013 Castiglione della Pescaia, ItalyChemical evolution in the Universe: the next 30 years Chemical evolution in the Universe: the next 30 years 16-20 Sept, 2013 Castiglione della Pescaia, Italy16-20 Sept, 2013 Castiglione della Pescaia, Italy

C. Morossi, M. Franchini, P. Di Marcantonio INAF-Osservatorio Astronomico Trieste, Italy

M.L. MalagniniDip. Fisica, Univ. Trieste, Italy

& INAF

M. ChavezINAOE, Mexico

Lick/SDSS library v2.0: a new tool to compute model of stellar populations with variable Alpha element

abundance ratios


Lick/SDSS Spectral IndicesLick/SDSS Spectral Indices


Lick/SDSS library v1.0 library v1.0 (Franchini et al. 2010)(Franchini et al. 2010)Lick/SDSS library v1.0 library v1.0 (Franchini et al. 2010)(Franchini et al. 2010)

Computed starting from synthetic spectra degraded at R=1800 (like SDSS)

Two grids of HiRes synthetic spectra:

Solar Scaled [ /Fe] = +0.0 (SSA) and -enhanced [ /Fe] = +0.4 (NSSA)

starting from Kurucz atmosphere models (ATLAS9) computed with solar and -enhanced ODF’s by Castelli (2003)

using SPECTRUM V.2.75 (Gray and Corbally 1994)

There is full consistency between synthetic spectra and the ODF of the atmosphere models

Teff : 3500-7000 K (250 K step)

log g: 0.5- 5.0 dex (0.5 dex step) [Fe/H]=-2.5,-2.0,-1.5,-1.0,-0.5,

[Fe/H]=-2.5,-2.0,-1.5,-1.0,-0.5,0.0,+0.2,+0.5 (NSSA)

[Fe/H]=-2.5,-2.0,-1.5,-1.0,-0.5,0.0,+0.2,+0.5 (SSA).0,+0.2,+0.5 (SSA)

[Fe/H]=-2.5,-2.0,-1.5,-1.0,-0.5,0.0,+0.2,+0.5 (NSSA)


Stellar atmospheric parametersStellar atmospheric parameters

From Lick/SDSS library v1.0 we (Franchini et al. ApJ 2011, 730, 117) derived the atmospheric parameters of more than 4000 F, G, and K SDSS stars by comparing synthetic and observed spectral indices

Indices are negligibly affected by errors in flux calibration and by reddening Narrow-band indices allow the measurement of the intensity of features of different chemical species separately Indices are characterized by higher S/N than the original spectra Homogeneous and self-consistent atmospheric parameter estimates

BUT ...


Lick/SDSS library v1.0 main limitations library v1.0 main limitationsLick/SDSS library v1.0 main limitations library v1.0 main limitations

• Only 2 values of [ /Fe]

• All element abundances varying in “lock steps”

• Matching with observed values via ad-hoc calibration


Is Is [ /Fe] the same for all the the same for all the elements?elements?Is Is [ /Fe] the same for all the the same for all the elements?elements?

The The [Mg/Fe][Mg/Fe] and and [Ca/Fe] [Ca/Fe] derived for more than 4000 F, G, and K SDSS-DR7 derived for more than 4000 F, G, and K SDSS-DR7 stars by means of stars by means of Lick/SDSS library v1.0 library v1.0 are different !are different !


Lick/SDSS library v2.0 library v2.0 (in preparation)(in preparation)Lick/SDSS library v2.0 library v2.0 (in preparation)(in preparation)

Kurucz atmosphere models computed with ATLAS12

Refined and more complete atomic and molecular line list

HiRes synthetic spectra computed with SPECTRUM V.2.76e (Gray and Corbally 1994)

several chemical compositions:

Solar Scaled with [Fe/H] from +0.5 to -3.0 with Δ[Fe/H]=0.25 (SSA)

-enhanced with [ /Fe] from +1.0 to -1.5 with Δ[α/Fe]=0.25 (NSSA)

Individual -element enhanced (i.e. Mg, Si, Ca, Ti)

full consistency between synthetic spectra and atmosphere models

No need of ad-hoc calibration for most of the synthetic indices

)


Are the new synthetic indices more reliable?Are the new synthetic indices more reliable?

Comparison with the observed ones requires:

•Good observations

•Accurate estimates of atmospheric stellar parameters


Good observationsGood observationsGood observationsGood observations

• The UVES Paranal Observatory Project: A Library of High- Resolution Spectra of Stars across the Hertzsprung-Russell Diagram (2003)Bagnulo, S.; Jehin, E.; Ledoux, C.; Cabanac, R.; Melo, C.; Gilmozzi, R

The Messenger (ISSN0722-6691), No.114, p. 10-14

• The ELODIE Archive (2004) Moultaka, J.; Ilovaisky, S. A.; Prugniel, P.; Soubiran, C.

The Publications of the Astronomical Society of the Pacific, Volume 116, Issue 821, pp. 693

• The Indo-US Library of Coudé Feed Stellar Spectra (2004)Valdes, Francisco; Gupta, Ranjan; Rose, James A.; Singh, Harinder P.; Bell, David J.

The Astrophysical Journal Supplement Series, Volume 152, Issue 2, pp. 251-259.

• Medium-resolution Isaac Newton Telescope library of empirical spectra - II. The stellar atmospheric parameters . (2007) Cenarro, A. J.; Peletier, R. F.; Sánchez-Blázquez, P.; Selam, S. O.; Toloba, E.; Cardiel, N.;

Falcón-Barroso, J.; Gorgas, J.; Jiménez-Vicente, J.; Vazdekis, A

Monthly Notices of the Royal Astronomical Society, Volume 374, Issue 2, pp. 664-690


Accurate estimates of atmospheric stellar parameters (1)Accurate estimates of atmospheric stellar parameters (1)Accurate estimates of atmospheric stellar parameters (1)Accurate estimates of atmospheric stellar parameters (1)

• The Chemical Evolution of the Galactic Disk - Part One - Analysis and Results Edvardsson, B.; Andersen, J.; Gustafsson, B.; Lambert, D. L.; Nissen, P. E.; Tomkin, J. < .Astron Astrophys., 275, 101 (1993)>

• Abundances and Kinematics of Field Halo and Disk Stars I: Observational Data and Abundance Analysis Fulbright J.P. . <Astron. J. 120, 1841 (2000)>

• The chemical compositions of Galactic disc F and G dwarfs Reddy, Bacham E.; Tomkin, Jocelyn; Lambert, David L.; Allende Prieto, Carlos <M.N.R.A.S., 340, 304 (2003)>

• Stellar chemical signatures and hierarchical galaxy formation. Venn K.A., Irwin M., Shetrone M.D., Tout C.A., Hill V., Tolstoy E. <Astron. J., 128, 1177-1195 (2004)>

• Alpha-, r-, and s-process element abundance trends in the Galactic thin and thick disks T. Bensby, S. Feltzing, I. Lundstrom, and I. Ilyin <Astron. Astrophys. 433l, 185 (2005)>

• Giants in the local region. Luck R.E., Heiter U. <Astron. J., 133, 2464-2486 (2007)>• Photospheric CNO abundances of solar-type stars. Takeda Y., Honda S. <Publ. Astron. Soc. Jap.,

57, 65-82 (2005)>• Fundamental parameters and elemental abundances of 160 F-G-K stars based on OAO spectrum

database. Takeda Y. <Publ. Astron. Soc. Jap., 59, 335-356 (2007)>• A holistic approach to carbon-enhanced metal-poor stars. Masseron T., Johnson J.A., Plez B., Van

Eck S., Primas F., Goriely S., Jorissen A. <Astron. Astrophys., 509, A93 (2010)>• Homogeneous photospheric parameters and C abundances in G and K nearby stars with and without

planets. Da Silva R., Milone A., Reddy B.E. <Astron. Astrophys. 526, A71 (2011)>• …


Accurate estimates of atmospheric stellar parameters (2)Accurate estimates of atmospheric stellar parameters (2)Accurate estimates of atmospheric stellar parameters (2)Accurate estimates of atmospheric stellar parameters (2)

The comparison of our results with published high-resolution analysis results shows that some of the latter may be affected by systematic errors and/or a lack of self-consistency.

I onizat ion fract ions1

f I I=

N I

N I I+

N I I

N I I+

N I I I

N I I(7.11)

1f I I I

=N I

N I I

N I I

N I I I+

N I I

N I I I+

N I I I

N I I I. (7.12)

El ect rons per nucleus

E =N e

N nuc lei= z N zf I I ( z ) + 2 z N zf I I I ( z )

z N z, (7.13)

Pr essure rat io

P g

P e=

(N ions + N atoms + N e) k TN ek T

=(N nuc lei + N e) k T

N ek T=

E + 1E

(7.14)

P e = P gE

E + 1. (7.15)


Accurate and complete atomic and molecular line list (1)Accurate and complete atomic and molecular line list (1)Accurate and complete atomic and molecular line list (1)Accurate and complete atomic and molecular line list (1)


Accurate and complete atomic and molecular line list (22)Accurate and complete atomic and molecular line list (22)Accurate and complete atomic and molecular line list (22)Accurate and complete atomic and molecular line list (22)

• Individual element abundancies

• Self-consistent models and spectra

• Empirical log gf’s• Different microturbulence

velocity for giants and dwarfs

•


Preliminary results based on 222 “bona-fide” stars (1)Preliminary results based on 222 “bona-fide” stars (1)Preliminary results based on 222 “bona-fide” stars (1)Preliminary results based on 222 “bona-fide” stars (1)


Preliminary results based on 222 “bona-fide” stars (2)Preliminary results based on 222 “bona-fide” stars (2)Preliminary results based on 222 “bona-fide” stars (2)Preliminary results based on 222 “bona-fide” stars (2)


Thank you

Chemical evolution in the Universe: the next 30 years Chemical evolution in the Universe: the next 30 years 16-20 Sept, 2013 Castiglione della Pescaia, Italy16-20 Sept, 2013 Castiglione della Pescaia, ItalyChemical evolution in the Universe: the next 30 years Chemical evolution in the Universe: the next 30 years 16-20 Sept, 2013 Castiglione della Pescaia, Italy16-20 Sept, 2013 Castiglione della Pescaia, Italy

c. morossi , m . franchini , p . di marcantonio

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