J/ApJS/260/27 R-Process Alliance: UV sp. of HD 222925 (Roederer+, 2022)
The R-Process Alliance: a nearly complete r-process abundance template derived
from ultraviolet spectroscopy of the r-process-enhanced metal-poor star
HD222925.
Roederer I.U., Lawler J.E., Den Hartog E.A., Placco V.M., Surman R.,
Beers T.C., Ezzeddine R., Frebel A., Hansen T.T., Hattori K., Holmbeck E.M.,
Sakari C.M.
<Astrophys. J. Suppl. Ser., 260, 27 (2022)>
=2022ApJS..260...27R 2022ApJS..260...27R
ADC_Keywords: Abundances; Stars, metal-deficient; Spectra, ultraviolet
Keywords: Nucleosynthesis ; R-process ; Stellar abundances ;
Ultraviolet astronomy ; Spectral line identification
Abstract:
We present a nearly complete rapid neutron-capture process (r-process)
chemical inventory of the metal-poor ([Fe/H]=-1.46±0.10)
r-process-enhanced ([Eu/Fe]=+1.32±0.08) halo star HD 222925. This
abundance set is the most complete for any object beyond the solar
system, with a total of 63 metals detected and seven with upper
limits. It comprises 42 elements from 31≤Z≤90, including elements
rarely detected in r-process-enhanced stars, such as Ga, Ge, As, Se,
Cd, In, Sn, Sb, Te, W, Re, Os, Ir, Pt, and Au. We derive these
abundances from an analysis of 404 absorption lines in ultraviolet
spectra collected using the Space Telescope Imaging Spectrograph on
the Hubble Space Telescope and previously analyzed optical spectra. A
series of appendices discusses the atomic data and quality of fits for
these lines. The r-process elements from Ba to Pb, including all
elements at the third r-process peak, exhibit remarkable agreement
with the solar r-process residuals, with a standard deviation of the
differences of only 0.08dex (17%). In contrast, deviations among the
lighter elements from Ga to Te span nearly 1.4 dex, and they show
distinct trends from Ga to Se, Nb through Cd, and In through Te. The
r-process contribution to Ga, Ge, and As is small, and Se is the
lightest element whose production is dominated by the r-process. The
lanthanide fraction, log XLa=-1.39±0.09, is typical for r-process-
enhanced stars and higher than that of the kilonova from the GW170817
neutron-star merger event. We advocate adopting this pattern as an
alternative to the solar r-process-element residuals when confronting
future theoretical models of heavy-element nucleosynthesis with
observations.
Description:
HD 222925 was observed with the Space Telescope Imaging Spectrograph
(STIS) on board the Hubble Space Telescope (HST) between
2019-October-3 and 2020-March-20.
Observations were made using the E230H echelle grating, the 0.2"x0.09"
slit, and the near-UV Multianode Microchannel Array detector. This
setup produces spectra with a resolving power of R=114000. Five
central wavelength settings were used (i2063, i2313, i2563, i2812, and
c3012), resulting in complete wavelength coverage from 1936 to 3145Å.
The observations were made during 47 orbits spread across 17 visits.
We also revisit the optical spectrum of HD 222925 presented in
Roederer+ (2018, J/ApJ/865/129). That spectrum was collected using the
Magellan Inamori Kyocera Echelle spectrograph (MIKE) mounted on the
Landon Clay (Magellan II) Telescope at Las Campanas Observatory,
Chile. It has R=68000 in the blue (3330≤λ≤5000Å) and
R=61000 in the red (5000≤λ≤9410Å), with S/N of several
hundred per pixel.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
23 45 17.61 -61 54 42.8 HD 222925 = TYC 9127-939-1
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 42 411 Line atomic data, references, and derived abundances
table3.dat 39 70 *Recommended metal abundances in HD 222925
tablea1.dat 56 150 Hyperfine structure line component patterns
for CoII lines
tablea2.dat 56 9 Hyperfine structure line component patterns
for the AsIλ2288 line
tablea3.dat 60 6 Hyperfine structure and isotope shift line
component pattern for the InIIλ2306 line
tablea4.dat 60 44 Hyperfine structure and isotope shift line
component patterns for SbI lines
tablea5.dat 60 40 Estimated isotope shift line component patterns
for WII lines
tablea6.dat 60 60 Hyperfine structure and isotope shift line
component patterns for ReII lines
tablea7.dat 60 18 Hyperfine structure and isotope shift line
component pattern for the IrIλ2924 line
tablea8.dat 60 8 Hyperfine structure and isotope shift line
component pattern for the PtIλ2274 line
tablea9.dat 56 4 Hyperfine structure line component pattern
for the AuIλ2675 line
refs.dat 182 61 References
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Note on table3.dat: Readers interested in the details of why these
recommendations are made are encouraged to consult the relevant
sections in Appendix A. The C abundance is corrected for stellar
evolution effects as described in Placco+ (2014, J/ApJ/797/21).
The O abundance is adopted from Navarrete+ (2015, J/ApJ/808/103).
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See also:
J/A+AS/102/435 : Transitions of SI in visible and infra-red (Biemont+ 1993)
J/A+A/342/881 : Uncertainties in r-abundance distribution (Goriely 1999)
J/A+A/354/169 : Metal-poor field stars abundances (Gratton+, 2000)
J/ApJ/530/783 : The r-process enriched giant HD 115444 (Westin+, 2000)
J/A+A/439/129 : HERES II. Spectroscopic analysis (Barklem+, 2005)
J/ApJS/167/292 : Laboratory transition prob. for Gd II (Den Hartog+, 2006)
J/ApJ/645/613 : Abundances of HD 221170 (Ivans+, 2006)
J/ApJS/169/120 : Transition probabilities for HfII and Hf (Lawler+, 2007)
J/ApJ/667/1267 : CrI transition probabilities (Sobeck+, 2007)
J/ApJS/182/51 : Transition prob. of rare earth elements (Lawler+, 2009)
J/A+A/503/545 : Equivalent widths of Li, Na, Fe, Ca in NGC 6397 (Lind+, 2009)
J/A+A/511/A68 : Transitions of CrII (Gurell+, 2010)
J/MNRAS/418/284 : s-process in low-metallicity stars. II. (Bisterzo+, 2011)
J/ApJS/194/35 : Atomic transition probabilities of Mn (Den Hartog+, 2011)
J/AJ/141/175 : Abundances in M15 RGB/RHB stars (Sobeck+, 2011)
J/A+A/537/A74 : RhII oscillator strengths (Quinet+, 2012)
J/ApJ/750/76 : R-process peaks elements in HD 160617 (Roederer+, 2012)
J/ApJ/771/67 : Abundances for 97 metal-poor stars. II. (Ishigaki+, 2013)
J/ApJS/208/27 : Sun and HD 84937 TiII log(gf) and abundances (Wood+, 2013)
J/ApJ/794/58 : Metal-poor stars in the thick disk of the MW (Beers+, 2014)
J/ApJ/787/10 : Solar s-process contributions (Bisterzo+, 2014)
J/ApJ/797/21 : Carbon-enhanced metal-poor stars (Placco+, 2014)
J/ApJ/797/69 : Abundances of late-type stars (Roederer+, 2014)
J/AJ/147/136 : Stars of very low metal abundance. VI. (Roederer+, 2014)
J/ApJS/214/18 : VII log(gf) values, and V abundance in HD 84937 (Wood+ 2014)
J/ApJS/211/20 : NiI transition probability measurements (Wood+, 2014)
J/ApJ/807/171 : SkyMapper Survey metal-poor star sp. (Jacobson+, 2015)
J/ApJS/220/13 : Co I transition probabilities (Lawler+, 2015)
J/ApJ/808/103 : Kapteyn moving group star abundances (Navarrete+, 2015)
J/ApJS/216/1 : New FeI level energies from stellar spectra (Peterson+, 2015)
J/ApJ/812/109 : HST & Keck sp. of bright CEMP-s stars (Placco+, 2015)
J/MNRAS/460/884 : EMBLA survey. Galactic bulge metal-poor stars (Howes+, 2016)
J/ApJ/819/135 : Lithium-rich giants in globular clusters (Kirby+, 2016)
J/ApJ/821/37 : Abundances of metal-poor star HD 94028 (Roederer+, 2016)
J/ApJ/824/L19 : Carbon-enhanced metal-poor star BD+44493 (Roederer+, 2016)
J/ApJ/817/53 : Fe-group elemental abundances in HD84937 (Sneden+, 2016)
J/ApJS/228/10 : Transition prob. for 183 lines of Cr II (Lawler+, 2017)
J/ApJS/229/23 : FeI level energies from star spectra. II. (Peterson+, 2017)
J/ApJ/858/92 : RPA Southern Pilot Search of 107 Stars (Hansen+, 2018)
J/ApJ/857/2 : Abundances in 6 metal-poor stars (Roederer+, 2018)
J/AJ/156/179 : r-process-enhanced field stars kinematics (Roederer+, 2018)
J/ApJ/865/129 : Abundance analysis of HD 222925 (Roederer+, 2018)
J/ApJ/860/125 : Six warm metal-poor stars iron abundances (Roederer+, 2018)
J/ApJ/868/110 : R-Process Alliance: 1st release in Gal. halo (Sakari+, 2018)
J/ApJ/882/40 : Lanthanide fraction distribution of stars (Ji+, 2019)
J/ApJ/890/119 : Iron abundances in 3 very metal-poor stars (Cowan+, 2020)
J/ApJ/898/150 : High-res. MIKE obs. of metal-poor stars (Ezzeddine+, 2020)
J/ApJS/249/30 : R-Process Alliance: metal-poor star sp. (Holmbeck+, 2020)
J/ApJ/900/106 : Vanadium abundances for 255 metal-poor stars (Ou+, 2020)
J/ApJ/905/20 : Metal-poor stars observed with SALT/HRS (Rasmussen+, 2020)
J/ApJ/908/79 : The r-process Alliance; abund. in 519 stars (Gudin+, 2021)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- Sp Species
5 A1 --- n_Sp [ab] Flag on Sp (1)
7- 14 F8.3 0.1nm lambda [2024.3/6757.13] Wavelength in Angstroms
16- 19 F4.2 eV Elow [0/8.12] Energy of lower level of transition
21- 25 F5.2 [-] loggf [-7.2/1.02] Log of degeneracy times
oscillator strength
27- 28 I2 --- r_loggf [1/61] Reference for loggf (see refs.dat file)
30 A1 --- l_loge(X) Limit on loge(X)
32- 36 F5.2 [-] loge(X) [-0.9/6.7] Log epsilon abundance of element X
38- 42 F5.3 [-] e_loge(X) [0.05/0.4]? Uncertainty on loge(X)
--------------------------------------------------------------------------------
Note (1): Flag as follows:
a = The two AlI transitions at 2204.619 (E.P.=0.01 eV, log(gf)=-2.29,
NIST grade C) and 2204.660Å form a single line in our spectrum.
b = The two CuI transitions at 2024.323 and 2024.337Å form a single
line in our spectrum; HFS patterns are known for both lines, and the
NIST ASD lists B grades for both log(gf) values.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Z [3/92] Atomic number
4- 5 A2 --- Ion Element symbol
7 A1 --- l_loge(X) Limit flag on log(eps)(X)
9- 13 F5.2 [-] loge(X) [-0.9/7.65] Log epsilon abundance of element X
15 A1 --- l_[X/H] Limit flag on [X/H]
17- 21 F5.2 [-] [X/H] [-2.3/0.15]? The [X/H] abundance ratio
23- 26 F4.2 [-] e_[X/H] [0.07/0.27]? Uncertainty in [X/H]
28 A1 --- l_[X/Fe] Limit flag on [X/Fe]
30- 34 F5.2 [-] [X/Fe] [-0.84/1.61]? The [X/Fe] abundance ratio
36- 39 F4.2 [-] e_[X/Fe] [0.04/0.27]? Uncertainty in [X/Fe] (1)
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Note (1): The uncertainties in [X/Fe] abundance ratios also approximate the
uncertainty in abundance ratios of other elements relative to each
other; e.g., [Ba/Eu].
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea[1-9].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 F9.3 cm-1 WaveNum [34180.4/49245.4] Center-of-gravity
wavenumber (1)
11- 19 F9.4 0.1nm WaveAir [2029.9/2924.8] Center-of-gravity air wavelength
in Angstroms (1)
21- 23 F3.1 -- Fupp [0/7.5]? Component upper level F or
total angular momentum (not for Table 8)
25- 27 F3.1 -- Flow [0.5/8.5]? Component lower level F
or total angular momentum (not for Table 8)
29- 37 F9.6 cm-1 CWavecm [-1.7/2.3] Component offset wavenumber with
respect to center-of-gravity wavenumber (1)
39- 47 F9.6 0.1nm CWaveA [-0.2/0.09] Component offset wavelength with
respect to center-of-gravity wavelength
in Angstroms (1)
49- 56 F8.6 -- Str [0/1]? Component strength normalized
to sum to 1 for each isotope (not for Table 8)
58- 60 I3 --- Iso [113/198]? Isotope (not for Tables 4, 5 and 12)
--------------------------------------------------------------------------------
Note (1): Energy levels from the NIST ASD and the index of air
(Peck & Reeder 1972JOSA...62..958P 1972JOSA...62..958P) are used to compute the
center-of-gravity wavenumbers and air wavelengths. Line component
positions are given relative to those values.
The center-of-gravity wavenumber for the AsI 2288 line is from Howard
& Andrew (1985JOSAB...2.1032H 1985JOSAB...2.1032H).
For ReII lines (Table 9), center-of-gravity wavenumbers and air
wavelengths are given with component positions relative to those
values.
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Byte-by-byte Description of file: refs.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Ref Reference code
4- 22 A19 --- BibCode ADS bibcode of the reference
24- 41 A18 --- Auth First author's name(s)
43-182 A140 --- Comm Comment
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 01-Aug-2022