J/A+A/607/A91 CS 29497-004 abundances (Hill+, 2017)
The Hamburg/ESO R-process Enhanced Star survey (HERES).
XI. The highly r-process-enhanced star CS 29497-004.
Hill V., Christlieb N., Beers T.C., Barklem P.S., Kratz K.-L.,
Nordstrom B., Pfeiffer B., Farouqi K.
<Astron. Astrophys. 607, A91 (2017)>
=2017A&A...607A..91H 2017A&A...607A..91H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, giant ; Spectroscopy ; Abundances ; Equivalent widths
Keywords: stars: abundances - stars: individual: CS 29497-004 -
stars: Population II - stars: chemically peculiar - Galaxy: halo
Abstract:
We report an abundance analysis for the highly r-process-enhanced
(r-II) star CS 29497-004, a very metal-poor giant with solar system
Teff=5013K and [Fe/H]=-2.85, whose nature was initially discovered in
the course of the HERES project. Our analysis is based on high
signal-to-noise ratio, high-resolution (R∼75000) VLT/UVES spectra and
MARCS model atmospheres under the assumption of local thermodynamic
equilibrium, and obtains abundance measurements for a total of 46
elements, 31 of which are neutron-capture elements. As is the case for
the other ∼25 r-II stars currently known, the heavy-element abundance
pattern of CS 29497-004 well-matches a scaled solar system second peak
r-process-element abundance pattern. We confirm our previous detection
of Th, and demonstrate that this star does not exhibit an "actinide
boost". Uranium is also detected (logε(U)=-2.20±0.30),
albeit with a large measurement error that hampers its use as a
precision cosmochronometer. Combining the various elemental
chronometer pairs that are available for this star, we derive a mean
age of 12.2±3.7Gyr using the theoretical production ratios from
published waiting-point approximation models. We further explore the
high-entropy wind model (Farouqi et al., 2010ApJ...712.1359F 2010ApJ...712.1359F)
production ratios arising from different neutron richness of the
ejecta (Ye), and derive an age of 13.7±4.4Gyr for a best-fitting
Ye=0.447. The U/Th nuclei-chronometer is confirmed to be the most
resilient to theoretical production ratios and yields an age of
16.5±6.6Gyr. Lead (Pb) is also tentatively detected in CS 29497-004,
at a level compatible with a scaled solar r-process, or with the
theoretical expectations for a pure r-process in this star.
Description:
High-resolution spectra of CS 29497-004 were obtained with UVES at
VLT-UT2 during October-December 2002 and July-August 2003. A
total of 22 exposures were obtained with the BLUE346 setting, and six
with the BLUE437 setting. In both cases Image Slicer #2 was used,
yielding a nominal resolving power of
R=λ/Δλ=75000. The total useful wavelength range
covered by these two settings is 3050-4980Å in the rest frame of
the star.
Objects:
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RA (2000) DE Designation(s)
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00 28 06.92 -26 03 04.2 CS 29497-004 = BPS CS 29497-004
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 54 279 Neutron-capture elements linelist and individual
abundances in CS 29497-004
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See also:
J/A+A/439/129 : HERES II. Spectroscopic analysis (Barklem+, 2005)
J/A+A/516/A46 : HERES V. HE 2327-5642 abundance analysis (Mashonkina+, 2010)
J/A+A/528/A92 : HERES VI. Galactic chemical evolution of Si & C (Zhang+, 2011)
Byte-by-byte Description of file: tableb1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 A5 --- Species Species
7- 14 F8.3 0.1nm lambda Wavelength
16- 19 F4.2 eV EP Energy potential
21- 26 F6.3 [-] loggf Oscillator strength
28- 29 I2 --- r_loggf Reference for loggf (1)
31 I1 --- r_HFS ? Reference for hyperfine splitting parameters
used (2)
33- 36 F4.1 0.1pm EW ? Equivalent width
38- 40 A3 --- n_EW [syn] syn for synthetic
41 A1 --- --- [(]
42- 46 F5.1 0.1nm EWsyn ? Synthetic equivalent width
47 A1 --- --- [)]
49- 54 F6.3 [-] logeps Abundance
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Note (1): References for log gf sources as follows:
1 = Sneden et al. (2003ApJ...591..936S 2003ApJ...591..936S)
2 = Sneden et al. (1996ApJ...467..819S 1996ApJ...467..819S)
3 = Cowley & Corliss (1983MNRAS.203..651C 1983MNRAS.203..651C)
4 = Biemont et al. (1981ApJ...248..867B 1981ApJ...248..867B)
5 = Biemont et al. (1984A&A...131..364B 1984A&A...131..364B)
6 = Hannaford et al. (1985A&A...143..447H 1985A&A...143..447H)
7 = Whaling & Brault (1988, Phys. Scr, 38, 707)
8 = Salih & Lawler (1985, Journal of the Optical Society of America B Optical
Physics, 2, 422)
9 = Kwiatkowski et al. (1982A&A...112..337K 1982A&A...112..337K)
10 = Duquette & Lawler (1985, Journal of the Optical Society of America B
Optical Physics, 2, 1948)
11 = Corliss & Bozman (1962, Experimental transition probabilities for spectral
lines of seventy elements; derived from the NBS Tables of spectral-line
intensities)
12 = Migdalek (1978, J. Quant. Spec. Radiat. Transf., 20, 81)
13 = Miles & Wiese (1969, Atomic Data, 1, 1)
14 = McWilliam (1998AJ....115.1640M 1998AJ....115.1640M)
15 = Lawler et al. (2001ApJ...556..452L 2001ApJ...556..452L)
16 = DREAM database (Palmeri et al. 2000, Phys. Scr, 61, 323)
17 = Ivarsson et al. (2001. Phys. Scr, 64, 455)
18 = Den Hartog et al. (2003ApJS..148..543D 2003ApJS..148..543D)
19 = Lawler et al. (2006, Cat. J/ApJS/162/227)
20 = Lawler et al. (2001ApJ...563.1075L 2001ApJ...563.1075L)
21 = Lawler et al. (2001ApJS..137..341L 2001ApJS..137..341L)
22 = Lawler et al. (2004ApJ...604..850L 2004ApJ...604..850L)
23 = Lawler et al. (2008ApJS..178...71L 2008ApJS..178...71L)
24 = Lawler et al. (2007, Cat. J/ApJS/169/120)
25 = Ivarsson et al. (2003A&A...409.1141I 2003A&A...409.1141I)
26 = Grevesse (1969, Sol. Phys., 6, 381)
27 = Nilsson et al. (2002A&A...382..368N 2002A&A...382..368N)
28 = Nilsson et al. (2002A&A...381.1090N 2002A&A...381.1090N)
Note (2): References for hyperfine splitting parameters used as follows:
1 = McWilliam (1998AJ....115.1640M 1998AJ....115.1640M)
2 = Lawler et al. (2001ApJ...556..452L 2001ApJ...556..452L)
3 = Ivarsson et al. (2001, Phys. Scr, 64, 455)
4 = Lawler et al. (2001ApJ...563.1075L 2001ApJ...563.1075L)
5 = Lawler et al. (2001ApJS..137..341L 2001ApJS..137..341L)
6 = Lawler et al. (2004ApJ...604..850L 2004ApJ...604..850L)
7 = Martensson-Pendrill et al. (1994, 1994, Phys. Rev. A, 49, 3351)
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History:
From electronic version of the journal
References:
Christlieb et al., Paper I 2004A&A...428.1027C 2004A&A...428.1027C
Barklem et al., Paper II 2005A&A...439..129B 2005A&A...439..129B, Cat. J/A+A/439/129
Jonsell et al., Paper III 2006A&A...451..651J 2006A&A...451..651J
Hayek et al., Paper IV 2009A&A...504..511H 2009A&A...504..511H
Mashonkina et al., Paper V 2010A&A...516A..46M 2010A&A...516A..46M, Cat. J/A+A/516/A46
Zhang et al., Paper VI 2011A&A...528A..92Z 2011A&A...528A..92Z, Cat. J/A+A/528/A92
Ren et al., Paper VII 2012A&A...537A.118R 2012A&A...537A.118R
Cui et al., Paper VIII 2013A&A...558A..36C 2013A&A...558A..36C
Mashonkina & Christlieb, Paper IX 2014A&A...565A.123M 2014A&A...565A.123M
Mashonkina et al., Paper X 2014A&A...569A..43M 2014A&A...569A..43M
(End) Patricia Vannier [CDS] 14-Nov-2017