2011A&A...530A..15N


Query : 2011A&A...530A..15N

2011A&A...530A..15N - Astronomy and Astrophysics, volume 530A, 15-15 (2011/6-1)

Two distinct halo populations in the solar neighborhood. II. Evidence from stellar abundances of Mn, Cu, Zn, Y, and Ba.

NISSEN P.E. and SCHUSTER W.J.

Abstract (from CDS):

Current models of galaxy formation predict that the Galactic halo was assembled hierarchically. By measuring abundance ratios in stars it may be possible to identify substructures in the halo resulting from this process. A previous study of 94 dwarf stars with -1.6<[Fe/H]←0.4 in the solar neighborhood has revealed the existence of two distinct halo populations with a systematic difference in [α/Fe] at a given metallicity. In continuation of that work, abundances of Mn, Cu, Zn, Y, and Ba are determined for the same sample of stars. Equivalent widths of atomic lines are measured from high resolution VLT/UVES and NOT/FIES spectra and used to derive abundance ratios from an LTE analysis based on MARCS model atmospheres. The analysis is made relative to two thick-disk stars, HD22879 and HD76932, such that very precise differential values are obtained. Systematic differences between the ``high-α'' and ``low-α'' halo populations are found for [Cu/Fe], [Zn/Fe], and [Ba/Y], whereas there is no significant difference in the case of [Mn/Fe]. At a given metallicity, [Cu/Fe] shows a large scatter that is closely correlated with a corresponding scatter in [Na/Fe] and [Ni/Fe]. The metallicity trends of [Cu/Fe], [Zn/Fe], and [Ba/Y] can be explained from existing nucleosynthesis calculations if the high-α stars formed in regions with such a high star formation rate that only massive stars and type II supernovae contributed to the chemical enrichment. The low-α stars, on the other hand, most likely originate from systems with a slower chemical evolution, characterized by additional enrichment from type Ia supernovae and low-mass AGB stars.

Abstract Copyright:

Journal keyword(s): stars: atmospheres - stars: abundances - Galaxy: abundances - Galaxy: halo - Galaxy: formation

VizieR on-line data: <Available at CDS (J/A+A/530/A15): table1.dat table2.dat table3u.dat table3f.dat>

Simbad objects: 105

goto Full paper

goto View the references in ADS

Number of rows : 105
N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2024
#notes
1 BD-03 56 PM* 00 29 26.6605338732 -02 20 57.055990746   11.269 10.648 10.630   ~ 33 0
2 HD 3567 PM* 00 38 31.9473242153 -08 18 33.392826667 9.54 9.70 9.23     F7/8wF3 207 0
3 NAME Sculptor Dwarf Galaxy G 01 00 09.4 -33 42 32   9.79 8.6 8.81   ~ 1358 4
4 IC 1613 GiC 01 04 48.4071 +02 07 10.185   10.42 10.01 9.77   ~ 1235 2
5 BD+47 451 SB* 01 34 22.6964788822 +48 44 27.436010103       10.4   K0 37 0
6 CD-61 282 PM* 01 36 05.8495294416 -61 05 03.492150337   10.63 10.10     G0 67 0
7 BD-01 306 PM* 02 14 40.2989460555 -01 12 05.123909214 9.60 9.631 9.066 8.712 8.377 G0 148 0
8 BD+26 377 PM* 02 16 56.5527833760 +27 24 48.417934572   11.06   9.9   G0 33 0
9 BD+32 467 PM* 02 34 13.2132669745 +33 00 05.091152673   11.13   10.2   G0 29 0
10 G 75-31 PM* 02 38 21.5033134703 +02 26 44.370557521   10.968 10.424 10.389   sd?F8 62 0
11 NAME Fornax Dwarf Spheroidal G 02 39 59.3 -34 26 57   9.02 7.4     ~ 1740 1
12 HD 17820 PM* 02 51 58.3551725257 +11 22 11.940361848 8.85 8.92   8.0   G5 111 0
13 G 5-19 PM* 03 11 26.5406862511 +12 37 09.570643728   11.77   11.0   ~ 46 0
14 Ross 374 PM* 03 26 59.7729638950 +23 46 35.925963580   11.36   10.6   F5 76 0
15 BD+20 571 PM* 03 27 39.4522217875 +21 02 34.994793492   11.36   10.8   G0 57 0
16 HD 22879 Pe* 03 40 22.0652879951 -03 13 01.124265616 7.146 7.222 6.667 6.346 6.016 G0VmF2 495 0
17 HD 25704 ** 04 01 44.6317980946 -57 12 24.598726799   8.65 8.10     F7V 151 0
18 HD 276029 PM* 04 03 55.2569638894 +39 44 19.199783595   11.27   10.3   F8 35 0
19 HD 284248 Pe* 04 14 35.5161858536 +22 21 04.252516252 9.49 9.68 9.23 8.77 8.43 sdG0 186 0
20 BD-06 855 PM* 04 14 58.1068708300 -05 37 48.859008052   11.278 10.601 10.192 9.794 ~ 84 0
21 HD 283807 PM* 04 44 42.0610259088 +25 56 09.599948808   10.78   9.7   G0 51 0
22 HD 277559 PM* 05 05 28.7086497622 +40 15 26.368031686   10.08   9.4   F5 58 0
23 HD 241253 PM* 05 09 56.9589768600 +05 33 26.741302308   10.24   9.4   G0 96 0
24 NAME LMC G 05 23 34.6 -69 45 22     0.4     ~ 17416 0
25 HD 246067 PM* 05 39 27.4342825426 +03 57 02.683945678       9.9   G0 54 0
26 HD 250792 Pe* 06 03 14.8636143602 +19 21 38.696218609 9.89 9.898 9.310 8.954 8.547 G1 165 0
27 BD+33 1279a PM* 06 13 49.8286755927 +33 25 02.118887862   11.65   11.1   F8 31 0
28 NAME Carina dSph G 06 41 36.7 -50 57 58   22.14 11.0 19.47   ~ 1124 0
29 G 192-43 PM* 06 47 44.9352596626 +58 38 34.532968179   10.75   10.1   F2 69 0
30 CD-33 3337 PM* 06 54 47.8101117384 -33 44 49.024262364   9.56 9.03     F5 93 0
31 G 103-69 PM* 06 54 56.2977228912 +35 30 58.636262340   11.55   11.1   sdF2 33 0
32 HD 51754 PM* 06 58 38.5387458343 -00 28 49.696648518 9.60 9.567 9.009 8.663 8.334 G2V 131 0
33 CD-57 1633 HV* 07 06 28.9516977109 -57 27 29.118927115   10.04 9.54     F7V 102 0
34 HD 59392 Pe* 07 28 03.2212916981 -38 00 41.278587469   10.17 9.7     F0V 92 0
35 CD-45 3283 PM* 07 34 18.5993129322 -45 16 42.883606401   11.08 10.43     G8V-VI 76 0
36 BD+00 2058A Pe* 07 43 43.9667566029 -00 04 00.973799875   10.653 10.202 9.888 9.578 sdF 81 0
37 BD+00 2058B PM* 07 43 44.0845747828 -00 03 49.307082024   11.741 11.253 10.909 10.593 ~ 52 0
38 HD 233511 PM* 08 19 22.5714563279 +54 05 09.623339988 10.02 10.24   9.4   F4 134 0
39 HD 76932 PM* 08 58 43.9327642391 -16 07 57.817644364 6.47 6.39 5.86     G2VFe-1.8CH-1 403 0
40 G 114-42 PM* 09 10 44.8904400192 -03 48 09.630888660   13.281 12.746 12.403 12.052 ~ 41 0
41 G 46-31 SB* 09 17 04.0007462520 +03 01 29.610961464   11.39   10.6   ~ 66 0
42 HD 237822 PM* 09 36 49.5206880772 +57 54 41.015334894   10.59   9.6   G3V 49 0
43 BD+29 1925 SB* 09 38 50.6066348979 +28 24 08.612287954       10.2   G5 30 0
44 BD-03 2764 PM* 09 45 37.8300847800 -04 40 28.499674008   11.333 10.849 10.499 10.175 ~ 35 0
45 NAME Sex A H2G 10 11 00.5 -04 41 30 12.48 12.13 11.93 11.78   ~ 727 2
46 HD 298986 PM* 10 17 14.8774744591 -52 29 18.694800089   10.46 10.03   9.48 F5 86 0
47 Ross 892 PM* 10 27 24.2460060626 +01 24 00.190284079   11.55   10.8   sdF8 71 0
48 CD-43 6810 PM* 11 08 40.0891980744 -44 15 33.814235556   10.38 9.82     F8 69 0
49 HD 97320 Pe* 11 11 00.7344001848 -65 25 37.745815656   9.769 9.269     F3V 145 0
50 BD+36 2165 PM* 11 12 47.9997679646 +35 43 43.885058670 9.98 10.19 9.76 9.34 9.02 G0 133 0
51 G 56-30 PM* 11 21 35.1061968969 +18 11 44.559215421   11.50   10.7   sd?G0 33 0
52 BD+20 2594 PM* 11 23 16.2307856395 +19 53 37.663112839   10.51   9.6   F9 75 0
53 BD+11 2369 PM* 11 32 34.1257455852 +10 54 11.307005592   10.73   9.7   G0 33 0
54 BD+26 2251 PM* 11 44 35.7049511770 +25 32 11.689104807   10.82   9.9   F6 90 0
55 BD+51 1696 Pe* 11 46 35.1556060454 +50 52 54.680145444 10.32 10.47   9.5   sdG0 153 0
56 BD-21 3420 PM* 11 55 28.4581009368 -22 23 13.324840296   10.649 10.107     F5 67 0
57 HD 103723 PM* 11 56 36.0251513496 -21 25 09.829610868   10.554 10.091     F5/6V 79 0
58 HD 105004 PM* 12 05 24.8526164337 -26 35 43.750181317   10.96 10.39     F9 107 0
59 HD 106516 SB* 12 15 10.55731 -10 18 44.6354 6.44 6.57 6.11     F9VFe-1.7CH-0.7 419 0
60 BD+02 2541 PM* 12 26 59.8614892629 +01 33 58.401336422   11.23   9.9   G3 52 0
61 HD 111980 SB* 12 53 15.0529661499 -18 31 20.013189741 8.80 8.91 8.38     F7V 172 0
62 HD 113679 PM* 13 05 52.8245053407 -38 30 59.990193435   10.342 9.797     G2/3V 100 0
63 HD 114762 SB* 13 12 19.7410686234 +17 31 01.630334317 7.78         F9VgF8mF4+M6?V 546 1
64 G 63-26 PM* 13 24 30.5997776592 +20 27 22.094791164   12.62 12.18 12.5   sd:F 61 0
65 NGC 5139 GlC 13 26 47.28 -47 28 46.1           ~ 3423 0
66 G 150-40 PM* 13 48 52.1482901497 +27 40 09.478619610       10.5   sdF9 36 0
67 HD 120559 PM* 13 51 40.3987847839 -57 26 08.350982731 8.679 8.647 7.982 7.605 7.217 G7VFe-1.4CH-1 155 0
68 HD 121004 PM* 13 53 58.1163626566 -46 32 19.522719077   10.112 9.522     G2V 151 0
69 HD 126681 PM* 14 27 24.9094012952 -18 24 40.454425566   9.939 9.535     G3V 189 0
70 BD+06 2932 PM* 14 43 17.9691516998 +05 49 39.761109950   11.33 10.51     G6V 106 0
71 HD 132475 PM* 14 59 49.7651173448 -22 00 45.815162806 8.98 9.11 8.55     F5/6V 240 1
72 NAME UMi Galaxy G 15 09 08.0 +67 13 21   13.60 10.6     ~ 1358 0
73 G 15-23 SB* 15 29 31.6798974496 +06 08 49.881802340   11.67   10.6   ~ 52 0
74 Wolf 615 PM* 15 58 18.6154199664 +02 03 06.102568584   11.41   10.3   ~ 35 0
75 BD+42 2667 Pe* 16 03 13.2988107325 +42 14 46.651500150   10.33   9.6   F5 145 0
76 HD 148816 PM* 16 30 28.4586254384 +04 10 41.602836534 7.75 7.81 7.28 6.82 6.49 F7V 310 0
77 NAME Dra dSph G 17 20 14.335 +57 55 16.39   12.40 10.6     ~ 1330 1
78 HD 159482 PM* 17 34 43.0816088882 +06 00 51.815208744   8.95   8.0   G0V 157 0
79 BD+18 3423 PM* 17 38 15.6094693200 +18 33 25.483804164 10.17 10.27   9.4   F6V 126 0
80 HD 160693 PM* 17 39 36.8721883235 +37 11 01.504256846 8.94 8.92   8.0   G0 210 0
81 NGC 6397 GlC 17 40 42.09 -53 40 27.6     5.17     ~ 1974 0
82 BD-08 4501 PM* 17 47 27.9712915686 -08 46 47.733112329   11.18 10.59     sdF8 127 0
83 HD 163810 ** 17 58 38.4538029750 -13 05 49.654844460 10.15 10.23 9.63     G3V 148 0
84 G 21-22 PM* 18 39 09.7158608590 +00 07 14.320687061   11.285 10.775 10.437 10.086 G4 64 0
85 HD 175179 PM* 18 54 23.2029803432 -04 36 18.621907480 9.56 9.61 9.03     G5V 120 0
86 HD 230409 PM* 19 00 43.3339876251 +19 04 28.418294811   10.78   9.6   G0 85 0
87 HD 177095 PM* 19 03 56.7108988306 -20 27 36.566397661   10.27 9.64     G6V 50 0
88 HD 179626 PM* 19 13 20.7189797919 -00 35 42.325251766   9.701 9.187 8.844 8.489 F5V 127 0
89 G 125-13 PM* 19 31 09.2290684806 +36 09 10.176410214   10.68   9.9   sdF7 68 0
90 HD 189558 PM* 20 01 00.2452184673 -12 15 20.353638621   8.28 7.73     F8/G2V 189 0
91 BD+05 4481 PM* 20 20 24.5608644037 +06 01 52.826286539   10.75   10.8   G4 63 0
92 HD 193901 PM* 20 23 35.8471605389 -21 22 14.226959304 9.08 9.22 8.67 8.17 7.87 F7V 280 0
93 HD 194598 PM* 20 26 11.9183775668 +09 27 00.429558608 8.62 8.82 8.34 7.90 7.56 F8 302 0
94 G 24-25 SB* 20 40 16.1053839864 +00 33 19.651652964       10.2   CEMP-s 50 0
95 HD 199289 PM* 20 58 08.5239126371 -48 12 13.459812756   8.82 8.30     F5V 122 0
96 HD 335471 PM* 21 03 06.1287954464 +29 28 56.213243727       9.7   G5 42 0
97 G 232-18 PM* 21 30 37.2926670600 +48 51 59.666714316       10.2   sd?G2 29 0
98 HD 205650 PM* 21 37 26.0286639804 -27 38 06.697265704   9.59 9.00     F6V 103 0
99 BD+26 4251 PM* 21 43 57.1238515464 +27 23 23.989925868       9.9   F6 88 0
100 BD+11 4725 SB* 22 05 40.6982164308 +12 22 36.113158501   10.19   9.2   G3 90 0
101 BD+07 4841 PM* 22 18 36.5059714907 +08 26 44.962089682   10.84   10.1   G0 116 0
102 G 127-26 PM* 22 23 49.0859208600 +24 23 33.136159236       10.2   F9 37 0
103 HD 219617 ** 23 17 05.04375 -13 51 03.5971 8.41 8.60 8.14 7.70 7.37 F8 309 0
104 HD 222766 PM* 23 43 34.9167361914 -07 55 24.014028099   10.769 10.115 9.728 9.349 G5/6V 82 0
105 NAME Galactic Bulge reg ~ ~           ~ 4290 0

To bookmark this query, right click on this link: simbad:objects in 2011A&A...530A..15N and select 'bookmark this link' or equivalent in the popup menu