J/ApJ/915/103 Oscillator strength ref. for Indus_0 & Indus_13 (Hansen+, 2021)
S5: the destruction of a bright dwarf galaxy as revealed by the chemistry of
the Indus stellar stream.
Hansen T.T., Ji A.P., Da Costa G.S., Li T.S., Casey A.R., Pace A.B.,
Cullinane L.R., Erkal D., Koposov S.E., Kuehn K., Lewis G.F., Mackey D.,
Simpson J.D., Shipp N., Zucker D.B., Bland-Hawthorn J., S5 Collaboration
<Astrophys. J., 915, 103 (2021)>
=2021ApJ...915..103H 2021ApJ...915..103H
ADC_Keywords: Abundances; Atomic physics; References; Associations, stellar;
Spectra, optical
Keywords: Stellar abundances ; Dwarf galaxies ; Milky Way stellar halo ;
Globular star clusters
Abstract:
The recently discovered Indus stellar stream exhibits a diverse
chemical signature compared to what is found for most other streams
due to the abundances of two outlier stars, Indus_0 and Indus_13.
Indus_13 exhibits an extreme enhancement in rapid neutron-capture
(r-)process elements with [Eu/Fe]=+1.81. It thus provides direct
evidence of the accreted nature of r-process-enhanced stars. In this
paper we present a detailed chemical analysis of the neutron-capture
elements in Indus_13, revealing the star to be slightly actinide poor.
The other outlier, Indus_0, displays a globular cluster-like signature
with high N, Na, and Al abundances, while the rest of the Indus stars
show abundances compatible with a dwarf galaxy origin. Hence, Indus_0
provides the first chemical evidence of a fully disrupted dwarf
containing a globular cluster. We use the chemical signature of the
Indus stars to discuss the nature of the stream progenitor which was
likely a chemically evolved system, with a mass somewhere in the range
from Ursa Minor to Fornax.
Description:
Indus_0 and Indus_13 were observed in July 2019 with the Magellan/MIKE
spectrograph as part of the S5 (see Li+ 2019, J/MNRAS/490/3508)
high-resolution follow-up program. Indus_13 was again observed in
November 2020. All observations were executed using the 0.7" slit and
2x2 CCD binning, yielding a typical resolution of R∼35000/28000 in the
blue and red arms, respectively.
Objects:
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RA (ICRS) DE Designation(s)
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22 05 30.96 -56 30 53.2 Indus_13 = Gaia DR2 6412626111276193920
23 24 01.76 -64 02 20.7 Indus_0 = Gaia DR2 6390575508661401216
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File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table3.dat 38 200 Atomic data and abundances for individual
neutron-capture element lines
--------------------------------------------------------------------------------
See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
II/371 : The Dark Energy Survey (DES): Data Release 2 (Abbott+, 2021)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
J/AJ/118/1671 : Fornax cluster 4 VI photometry (Buonanno+, 1999)
J/A+A/439/129 : HERES II. Spectroscopic analysis (Barklem+, 2005)
J/ApJS/167/292 : Laboratory transitions for Gd II (Den Hartog+, 2006)
J/ApJ/645/613 : Abundances of HD 221170 (Ivans+, 2006)
J/ApJS/162/227 : Transition probabilities for SmII (Lawler+, 2006)
J/ApJS/169/120 : Transition probabilities for HfII and Hf (Lawler+, 2007)
J/ApJ/701/1053 : Abundances of 8 stars in the Draco dSph (Cohen+, 2009)
J/ApJS/182/51 : Transitions of rare earth elements (Lawler+, 2009)
J/ApJS/182/80 : Rare earth abundances (Sneden+, 2009)
J/ApJ/719/931 : Chemical evolution of the UMi dSph (Cohen+, 2010)
J/A+A/523/A17 : Individual stars in Fornax dSph center (Letarte+, 2010)
J/AJ/141/175 : Abundances in M15 RGB/RHB stars (Sobeck+, 2011)
J/AJ/144/168 : Spectroscopy of Scl 1019417 and UMi 20103 (Kirby+, 2012)
J/AJ/144/4 : Dwarf galaxies in the Local Group (McConnachie+, 2012)
J/ApJ/751/102 : Equivalent widths of 9 RGB in Carina dSph (Venn+, 2012)
J/ApJ/779/102 : Metallicities of RGB stars in dwarf galaxies (Kirby+, 2013)
J/ApJ/797/15 : HST/WFC3 obs. in 4 metal-poor GCs of Fornax (Larsen+, 2014)
J/A+A/572/A88 : Measured EWs for Fornax RGB stars (Lemasle+, 2014)
J/A+A/569/A43 : HE 2252-4225 abundance analysis (Mashonkina+, 2014)
J/A+A/571/A47 : Extensive linelist of CH in stellar atm. (Masseron+, 2014)
J/A+A/581/A70 : Grid of NLTE EW & NLTE corr. BaII lines (Korotin+, 2015)
J/AJ/151/82 : 4 brightest red giants in Ret 2 (Roederer+, 2016)
J/ApJ/838/44 : Abund. of the brightest member of Tuc III (Hansen+, 2017)
J/A+A/607/A91 : CS 29497-004 abundances (Hill+, 2017)
J/ApJS/230/28 : The populations of Carina. II. Abundances (Norris+, 2017)
J/ApJ/858/92 : RPA Southern Pilot Search of 107 Stars (Hansen+, 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/868/110 : R-Process Alliance: 1st release in Gal. halo (Sakari+, 2018)
J/ApJ/882/40 : Lanthanide distribution of metal-poor stars (Ji+, 2019)
J/MNRAS/490/3508 : The Southern Stellar Stream Sp. Survey (S5) (Li+, 2019)
J/ApJ/882/177 : Abundances of 4 member stars of Tucana III (Marshall+, 2019)
J/MNRAS/484/2832 : Proper motions of MW globular clusters (Vasiliev, 2019)
J/ApJ/875/L13 : DECam r & i magnitudes in the Fornax 6 cluster (Wang+, 2019)
J/ApJ/898/150 : High-res. MIKE obs. of metal-poor stars (Ezzeddine+, 2020)
J/ApJ/897/183 : Abundances of 3 stars in Grus II galaxy (Hansen+, 2020)
J/ApJ/901/23 : Gjoll stream stars & abund. of 4 members (Hansen+, 2020)
J/ApJS/249/30 : R-Process Alliance: metal-poor star sp. (Holmbeck+, 2020)
J/AJ/160/181 : Chemical abundances in red giants with Magellan (Ji+, 2020)
J/A+A/641/A127 : 13 dsph and ultra-faint galaxies analysis (Reichert+, 2020)
J/ApJ/891/39 : LAMOST DR3 very metal-poor stars of Gal. halo (Yuan+, 2020)
J/ApJ/908/79 : The r-process Alliance abundances (Gudin+, 2021)
J/ApJ/912/52 : Abundances of 22 metal-poor stars in the MW (Gull+, 2021)
J/ApJ/907/10 : The VMP HK/HES stars (Limberg+, 2021)
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- ID Ion
6- 12 F7.2 0.1nm lambda [3702.85/7370.22] Wavelength in Angstroms
14- 17 F4.2 eV ExPot [0/2.94] Excitation potential in eV
20- 24 F5.2 [-] log(gf) [-1.93/0.81] log of degeneracy times
oscillator strength
26- 30 F5.2 [-] log(eps) [-0.3/2.01] log epsilon abundance
32- 35 F4.2 [-] e_log(eps) [0.06/0.7] Uncertainty in log(eps)
37- 38 I2 --- r_log(gf) [1/23] Reference code on log(gf) (1)
--------------------------------------------------------------------------------
Note (1): Reference as follows:
1 = Kramida et al. (2018), NIST Atomic Spectra Database (ver. 5.5.6);
2 = Biemont et al. (2011MNRAS.414.3350B 2011MNRAS.414.3350B);
3 = Ljung et al. (2006A&A...456.1181L 2006A&A...456.1181L);
4 = Wickliffe et al. (1994JQSRT..51..545W 1994JQSRT..51..545W);
5 = Kramida et al. (2018) NIST Atomic Spectra Database (ver. 5.5.6),
using HFS/IS from McWilliam (1998AJ....115.1640M 1998AJ....115.1640M);
6 = Lawler et al. (2001ApJ...556..452L 2001ApJ...556..452L), using HFS from
Ivans et al. (2006ApJ...645..613I 2006ApJ...645..613I) when available;
7 = Lawler et al. (2009ApJS..182...51L 2009ApJS..182...51L);
8 = Li et al. (2007PhyS...76..577L 2007PhyS...76..577L), using HFS from
Sneden et al. (2009ApJS..182...80S 2009ApJS..182...80S);
9 = Den Hartog et al. (2003ApJS..148..543D 2003ApJS..148..543D), using HFS/IS from
Roederer et al. (2008ApJ...675..723R 2008ApJ...675..723R) when available;
10 = Lawler et al. (2006ApJS..162..227L 2006ApJS..162..227L), using HFS/IS from
Roederer et al. (2008ApJ...675..723R 2008ApJ...675..723R) when available;
11 = Lawler et al. (2001ApJ...563.1075L 2001ApJ...563.1075L), using HFS/IS from
Ivans et al. (2006ApJ...645..613I 2006ApJ...645..613I);
12 = Den Hartog et al. (2006ApJS..167..292D 2006ApJS..167..292D);
13 = Lawler et al. (2001ApJS..137..341L 2001ApJS..137..341L), using HFS from
Lawler et al. (2001ApJS..137..351L 2001ApJS..137..351L);
14 = Wickliffe et al. (2000JQSRT..66..363W 2000JQSRT..66..363W);
15 = Lawler et al. (2004ApJ...604..850L 2004ApJ...604..850L), using HFS from
Lawler et al. (2009ApJS..182...51L 2009ApJS..182...51L);
16 = Lawler et al. (2008ApJS..178...71L 2008ApJS..178...71L);
17 = Wickliffe & Lawler (1997JOSAB..14..737W 1997JOSAB..14..737W);
18 = Lawler et al. (2009ApJS..182...51L 2009ApJS..182...51L) for log(gf) values and HFS;
19 = Lawler et al. (2007ApJS..169..120L 2007ApJS..169..120L);
20 = Quinet et al. (2006A&A...448.1207Q 2006A&A...448.1207Q);
21 = Xu et al. (2007JQSRT.104...52X 2007JQSRT.104...52X), using HFS/IS from
Cowan et al. (2005ApJ...627..238C 2005ApJ...627..238C);
22 = Biemont et al. (2000MNRAS.312..116B 2000MNRAS.312..116B), using HFS/IS from
Roederer et al. (2012ApJS..203...27R 2012ApJS..203...27R);
23 = Nilsson et al. (2002A&A...382..368N 2002A&A...382..368N);
24 = Nilsson et al. (2002A&A...381.1090N 2002A&A...381.1090N).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 19-Dec-2022