J/ApJ/817/53 Fe-group elemental abundance analysis in HD84937 (Sneden+, 2016)
Iron-group abundances in the metal-poor main-sequence turnoff star HD 84937.
Sneden C., Cowan J.J., Kobayashi C., Pignatari M., Lawler J.E.,
Den Hartog E.A., Wood M.P.
<Astrophys. J., 817, 53 (2016)>
=2016ApJ...817...53S 2016ApJ...817...53S (SIMBAD/NED BibCode)
ADC_Keywords: Abundances ; Stars, metal-deficient ; Spectroscopy
Keywords: atomic data; Galaxy: evolution;
nuclear reactions, nucleosynthesis, abundances; stars: abundances
stars: individual: HD 84937; stars: Population II
Abstract:
We have derived new, very accurate abundances of the Fe-group elements
Sc through Zn (Z=21-30) in the bright main-sequence turnoff star
HD84937 based on high-resolution spectra covering the visible and
ultraviolet spectral regions. New or recent laboratory transition data
for 14 species of seven elements have been used. Abundances from more
than 600 lines of non-Fe species have been combined with about 550 Fe
lines in HD84937 to yield abundance ratios of high precision. The
abundances have been determined from both neutral and ionized
transitions, which generally are in agreement with each other. We find
no substantial departures from the standard LTE Saha ionization
balance in this [Fe/H]=-2.32 star. Noteworthy among the abundances are
[Co/Fe]=+0.14 and [Cu/Fe]=-0.83, in agreement with past studies of
abundance trends in this and other low-metallicity stars, and
<[Sc,Ti,V/Fe]≥+0.31 which has not been noted previously. A detailed
examination of scandium, titanium, and vanadium abundances in
large-sample spectroscopic surveys reveals that they are positively
correlated in stars with [Fe/H]←2; HD84937 lies at the high end of
this correlation. These trends constrain the synthesis mechanisms of
Fe-group elements. We also examine the Galactic chemical evolution
abundance trends of the Fe-group elements, including a new
nucleosynthesis model with jet-like explosion effects.
Description:
Solar and HD 84937 data sets are the same as in previous papers of
this series. The spectra have been discussed in detail by Lawler et
al. (2013ApJS..205...11L 2013ApJS..205...11L).
For the Sun we used the photospheric center-of-disk spectrum of
Delbouille et al. (1973apds.book.....D 1973apds.book.....D).
The ground-based spectrum of HD 84937 was obtained from the ESO Very
Large Telescope UVES archive. It extends over
3100≲λ≲10000Å, with resolving power R∼60000 and
signal-to-noise ratio S/N∼100 at 3500Å.
The vacuum-UV spectrum of HD 84937 comes from the Hubble Space
Telescope Imaging Spectrograph (HST/STIS) public archive, having been
part of proposal #7402 (PI: R. C. Peterson) with a wavelength range
2280≲λ≲3120Å and R∼25000.
Objects:
------------------------------------------------------
RA (ICRS) DE Designation(s)
------------------------------------------------------
09 48 56.10 +13 44 39.3 HD 84937 = TYC 834-654-1
------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table3.dat 52 627 Line Abundances for FeI and FeII
table4.dat 52 278 Line Abundances for Other Fe-Group Species
--------------------------------------------------------------------------------
See also:
J/A+A/577/A9 : Sc, V, Mn, and Co in Milky Way stars (Battistini+, 2015)
J/ApJS/220/13 : Co I transition probabilities (Lawler+, 2015)
J/ApJS/215/23 : FeI lifetimes & branching fractions (Den Hartog+, 2014)
J/ApJS/215/20 : Vanadium log(gf) and transition probabilities (Lawler+, 2014)
J/A+A/571/A47 : Extensive linelist of CH in stellar atm. (Masseron+, 2014)
J/ApJS/214/26 : Line lists for CN isotopes transitions (Sneden+, 2014)
J/ApJS/214/18 : VII log(gf) values, and V abundance in HD 84937 (Wood+ 2014)
J/MNRAS/441/3127 : FeI oscillator strengths for Gaia-ESO (Ruffoni+, 2014)
J/AJ/147/136 : Stars of very low metal abundance. VI. (Roederer+, 2014)
J/ApJS/211/20 : NiI transition probability measurements (Wood+, 2014)
J/ApJS/211/5 : Improved line data for the Swan system 12C13C (Ram+, 2014)
J/ApJS/210/23 : Line intensities in CN transitions (Brooke+, 2014)
J/ApJ/778/56 : Hamburg/ESO Survey extremely metal-poor stars (Cohen+, 2013)
J/ApJS/208/27 : Sun and HD 84937 TiII log(gf) and abundances (Wood+, 2013)
J/ApJS/207/26 : MgH in the A2Π-X2Σ+ system (Hinkle+, 2013)
J/A+A/554/A96 : Spectra of LiI(670.8nm) line in metal-poor stars (Lind+, 2013)
J/ApJ/764/21 : Stellar evolutionary models with 13-120Msun (Chieffi+, 2013)
J/ApJ/762/26 : Most metal-poor stars. II. Galactic halo stars (Yong+, 2013)
J/ApJS/194/35 : Atomic transition probabilities of Mn (Den Hartog+, 2011)
J/ApJ/724/341 : Nucleosynthesis of massive metal-free stars (Heger+, 2010)
J/A+A/511/A68 : Transitions of CrII (Gurell+, 2010)
J/ApJS/182/80 : Rare earth abundances (Sneden+, 2009)
J/ApJS/182/51 : Rare earth element transition probabilities (Lawler+, 2009)
J/ApJ/667/1267 : CrI transition probabilities (Sobeck+, 2007)
J/A+A/467/665 : Manganese abundances in the Galactic disk (Feltzing+, 2007)
J/A+A/439/129 : HERES II. Spectroscopic analysis (Barklem+, 2005)
J/A+A/416/1117 : Abundances in the early Galaxy (Cayrel+, 2004)
J/AJ/128/2402 : Extremely metal-poor star candidates abundances (Lai+, 2004)
J/A+A/404/187 : Equivalent widths for metal-poor stars (Gratton+, 2003)
J/MNRAS/340/304 : [X/Fe] of Galactic disc F and G dwarfs (Reddy+, 2003)
J/A+A/377/361 : Fe II transition probabilities and loggf (Pickering+, 2001)
J/ApJ/562/528 : Teff and log(g) of low-metallicity stars (Snider+, 2001)
J/AJ/120/1841 : Abundances & Kinematics of Halo & Disk Stars (Fulbright 2000)
J/A+AS/129/237 : G and K dwarfs abundances (Feltzing+ 1998)
J/AJ/90/2089 : Stars of very low metal abundance. I (Beers+, 1985)
Byte-by-byte Description of file: table[34].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.2 0.1nm lamAir [2297.7/8824.3] Wavelength in air; Angstroms
11- 16 A6 --- species Species designation
17- 24 F8.3 eV chi [0/6] Lower excitation energy
25- 31 F7.2 --- log(gf) [-5/0.7] Log of the gf value
32- 37 A6 --- Ref Source of the gf value (1)
41- 45 F5.2 --- log(e)S [3/7.7]? Abundance in the Sun
46 A1 --- f_log(e)S [n] n=no
48- 52 F5.2 --- log(e) [1/5.4]? Abundance in HD 84937
--------------------------------------------------------------------------------
Note (1): Source as follows:
Den14 = Den Hartog et al. (2014, J/ApJS/215/23);
Obr91 = O'Brian et al. (1991JOSAB...8.1185O 1991JOSAB...8.1185O);
Ruf14 = Ruffoni et al. (2014, J/MNRAS/441/3127);
NIST = NIST database (http://www.nist.gov/pml/data/asd.cfm)
Law89 = Lawler & Dakin (1989JOSAB...6.1457L 1989JOSAB...6.1457L);
Sob07 = Sobeck et al. (2007, J/ApJ/667/1267);
Gur10 = Gurell et al. (2010, J/A+A/511/A68);
Nil06 = Nilsson et al. (2006A&A...445.1165N 2006A&A...445.1165N);
Den11 = Den Hartog et al. (2011, J/ApJS/194/35);
Roe14 = Roederer et al. (2014, J/AJ/147/136)
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 07-Apr-2016