J/A+A/696/A210 Cu abundances (Caliskan+, 2025)
Revisiting inelastic Cu + H collisions and the non-LTE Galactic evolution of
copper.
Caliskan S., Amarsi A.M., Racca M., Koutsouridou I., Barklem P.S., Lind K.,
Salvadori S.
<Astron. Astrophys. 696, A210 (2025)>
=2025A&A...696A.210C 2025A&A...696A.210C (SIMBAD/NED BibCode)
ADC_Keywords: Atomic physics ; Abundances
Keywords: atomic processes - line: formation - radiative transfer -
stars: abundances - Galaxy: abundances
Abstract:
The Galactic evolution of copper remains poorly understood, partly
due to the strong departures from local thermodynamic equilibrium
(LTE) affecting CuI lines. A key source of uncertainty in non-LTE
modelling is the treatment of inelastic Cu+H collisions. We present
new rate coefficients based on a combined asymptotic LCAO (linear
combination of atomic orbitals) and free electron model approach,
which show significant differences from previous calculations.
Applying these updated rates to non-LTE stellar modelling, we find
reduced line-to-line scatter and improved consistency between
metal-poor dwarfs and giants. Our non-LTE analysis reveals a strong
upturn in the [Cu/Fe] trend towards lower [Fe/H]←1.7. We show that
this may reflect the interplay between external enrichment of Cu-rich
material of the Milky Way halo at low metallicities, and
metallicity-dependent Cu yields from rapidly rotating massive stars.
This highlights the unique diagnostic potential of accurate Cu
abundances for understanding both stellar and Galactic evolution.
Description:
abcor.dat contains the line-by-line non-LTE abundance correction for a
grid of stellar parameters.
abundances.dat contains the LTE and non-LTE [Cu/Fe] abundances for
each star studied in the paper.
CuLCAOstate.dat and Cufreestate.dat contain information about the
copper states included in the asymptotic LCAO and free electron
models, respectively.
CuLCAOrate.dat and Cufreerate.dat contain the Cu+H rate
coefficients calculated with the asymptotic LCAO and free electron
models, respectively.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
abcor.dat 78 273119 Line by line abundance corrections
abund.dat 90 834 Line averaged [Cu/Fe] abundances
culcaost.dat 34 30 Copper states in asymptotic LCAO model
culcaora.dat 29 18000 Rate coefficients for copper from
asymptotic LCAO model
cufreest.dat 33 69 Copper states in free electron model
cufreera.dat 29 190440 Rate coefficients for copper from
free electron model
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Byte-by-byte Description of file: abcor.dat
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Bytes Format Units Label Explanations
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6- 9 I4 K Teff Effective temperature
16- 19 F4.2 [cm/s2] logg Surface gravity
25- 29 F5.2 [-] [Fe/H] Metallicity
36- 39 F4.2 km/s Vmic Microturbulence
47- 52 F6.3 [-] [Cu/Fe]LTE Cu over Fe abundance (in LTE)
61- 65 F5.1 nm Line Wavelength of the line
73- 78 F6.3 --- LCAO+Free Abundance correction using LCAO+Free rate
coefficients
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Byte-by-byte Description of file: abund.dat
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Bytes Format Units Label Explanations
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1- 28 A28 --- Star Name of star
30- 33 I4 K Teff Effective temperature
35- 38 F4.2 [cm/s2] logg Surface gravity
40- 44 F5.2 [-] [Fe/H] Metallicity
46- 49 F4.2 km/s Vmic Microturbulence
51- 60 A10 ---- Pop Stellar population (from the source paper)
62- 76 A15 --- Ref Reference of the source paper (1)
78- 83 F6.3 [-] [Cu/Fe]LTE Cu over Fe abundance (in LTE)
85- 90 F6.3 [-] [Cu/Fe]NLTE Cu over Fe abundance (in NLTE using
LCAO+Free rate coefficients)
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Note (1): References as follows:
Delgado_Mena+17 = Delgado Mena et al., 2017A&A...606A..94D 2017A&A...606A..94D, Cat. J/A+A/606/A94
Yan+16 = Yan et al., 2016A&A...585A.102Y 2016A&A...585A.102Y, Cat. J/A+A/585/A102
Korotin+18 = Korotin et al., 2018MNRAS.480..965K 2018MNRAS.480..965K
Sneden+23 = Sneden et al., 2023ApJ...953...31S 2023ApJ...953...31S
Caffau+23 = Caffau et al., 2023MNRAS.518.3796C 2023MNRAS.518.3796C
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Byte-by-byte Description of file: culcaost.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- I State index
6- 17 A12 --- Label State configuration and term
26- 34 F9.6 eV E Cu level energy
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Byte-by-byte Description of file: culcaora.dat cufreera.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- I1 Initial state index
7- 9 I3 --- I2 Final state index
13- 17 I5 K T Temperature
21- 29 E9.3 cm3/s q Rate coefficient
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Byte-by-byte Description of file: cufreest.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- I State index
5- 11 A7 --- Label State configuration and term
25- 33 F9.6 eV E Cu level energy
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Acknowledgements:
Sema Caliskan, sema.caliskan(at)physics.uu.se
(End) Patricia Vannier [CDS] 03-Apr-2025