2018ApJ...852...99N

Query : 2018ApJ...852...99N

2018ApJ...852...99N - Astrophys. J., 852, 99-99 (2018/January-2)

Chemical abundance analysis of three α-poor, metal-poor stars in the ultrafaint dwarf galaxy Horologium I.

NAGASAWA D.Q., MARSHALL J.L., LI T.S., HANSEN T.T., SIMON J.D., BERNSTEIN R.A., BALBINOT E., DRLICA-WAGNER A., PACE A.B., STRIGARI L.E., PELLEGRINO C.M., DEPOY D.L., SUNTZEFF N.B., BECHTOL K., WALKER A.R., ABBOTT T.M.C., ABDALLA F.B., ALLAM S., ANNIS J., BENOIT-LEVY A., BERTIN E., BROOKS D., CARNERO ROSELL A., CARRASCO KIND M., CARRETERO J., CUNHA C.E., D'ANDREA C.B., DA COSTA L.N., DAVIS C., DESAI S., DOEL P., EIFLER T.F., FLAUGHER B., FOSALBA P., FRIEMAN J., GARCIA-BELLIDO J., GAZTANAGA E., GERDES D.W., GRUEN D., GRUENDL R.A., GSCHWEND J., GUTIERREZ G., HARTLEY W.G., HONSCHEID K., JAMES D.J., JELTEMA T., KRAUSE E., KUEHN K., KUHLMANN S., KUROPATKIN N., MARCH M., MIQUEL R., NORD B., ROODMAN A., SANCHEZ E., SANTIAGO B., SCARPINE V., SCHINDLER R., SCHUBNELL M., SEVILLA-NOARBE I., SMITH M., SMITH R.C., SOARES-SANTOS M., SOBREIRA F., SUCHYTA E., TARLE G., THOMAS D., TUCKER D.L., WECHSLER R.H., WOLF R.C. and YANNY B.

Abstract (from CDS):

We present chemical abundance measurements of three stars in the ultrafaint dwarf galaxy Horologium I, a Milky Way satellite discovered by the Dark Energy Survey. Using high-resolution spectroscopic observations, we measure the metallicity of the three stars, as well as abundance ratios of several α-elements, iron-peak elements, and neutron-capture elements. The abundance pattern is relatively consistent among all three stars, which have a low average metallicity of [Fe/H] ∼ -2.6 and are not α-enhanced ([α/Fe] ∼ 0.0). This result is unexpected when compared to other low-metallicity stars in the Galactic halo and other ultrafaint dwarfs and suggests the possibility of a different mechanism for the enrichment of Hor I compared to other satellites. We discuss possible scenarios that could lead to this observed nucleosynthetic signature, including extended star formation, enrichment by a Population III supernova, and or an association with the Large Magellanic Cloud.

Abstract Copyright: © 2018. The American Astronomical Society. All rights reserved.

Journal keyword(s): galaxies: abundances - galaxies: dwarf - stars: abundances - stars: chemically peculiar - stars: chemically peculiar

VizieR on-line data: <Available at CDS (J/ApJ/852/99): table1.dat table2.dat table3.dat table4.dat>

Simbad objects: 28

goto Full paper

goto View the references in ADS

Number of rows : 28
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 SDSS J001820.51-093939.2 Pe* 00 18 20.5090518552 -09 39 39.110446908           F9 23 0
2 NAME Tri II G 02 13 17.40 +36 10 42.4           ~ 130 0
3 NAME Segue 2 G 02 19 16.0 +20 10 31     15.2     ~ 262 0
4 G 4-36 PM* 02 43 22.0483919796 +13 25 56.981522451   11.989 11.471 11.133 10.795 ~ 69 0
5 NAME Hor I G 02 55 31.7 -54 07 08           ~ 141 0
6 DES J025535.19-540644.0 * 02 55 35.2141523568 -54 06 43.942433004           ~ 7 0
7 DES J025540.30-540807.2 * 02 55 40.3200708576 -54 08 07.221816348           ~ 6 0
8 DES J025543.79-540519.6 * 02 55 43.8082890384 -54 05 19.597500456           ~ 4 0
9 NAME Magellanic Clouds GrG 03 00 -71.0           ~ 7062 0
10 NAME Reticulum II G 03 35 42.1 -54 02 57           ~ 309 0
11 NAME Eridanus II G 03 44 21.1 -43 32 00           ~ 174 0
12 NAME LMC G 05 23 34.6 -69 45 22     0.4     ~ 17428 0
13 BD+80 245 Pe* 08 11 06.2398198478 +79 54 29.556322137   10.50 9.96 9.88   G0 112 0
14 NAME Segue 1 G 10 07 03.2 +16 04 25     15.3     ~ 465 1
15 NAME UMa I Galaxy G 10 34 52.80 +51 55 12.0     14.4     ~ 328 1
16 NAME UMa Region reg 11 00 +50.0           ~ 327 0
17 NAME Leo IV Dwarf Galaxy G 11 32 57.0 -00 32 00     15.1     ~ 383 1
18 NAME Coma Dwarf Galaxy G 12 26 59.0 +23 54 15     14.1     ~ 452 1
19 NAME CVn II dSph G 12 57 09.6 +34 19 12     16.1     ~ 263 2
20 NAME Bootes II G 13 58 00.0 +12 51 00     15.4     ~ 241 0
21 NAME Bootes Dwarf Spheroidal Galaxy G 14 00 00.0 +14 30 00     12.8     ~ 437 0
22 HD 140283 Pe* 15 43 03.0971190219 -10 56 00.595693188 7.508 7.711 7.212 6.63 8.21 F9VkA5mA1 937 0
23 * del Oph PM* 16 14 20.7390218758 -03 41 39.572826363 6.30 4.34 2.75 1.46 0.43 M0.5III 363 0
24 NAME Hercules Dwarf Galaxy G 16 31 02.0 +12 47 30     14.0     ~ 345 1
25 NAME Tuc II G 22 51 55.1 -58 34 08           ~ 155 0
26 NAME Grus I G 22 56 42.4 -50 09 48           ~ 102 0
27 V* BX Scl SX* 23 43 54.4551676392 -28 18 34.627551660   13.82 13.56     A 42 0
28 NAME Tuc III G 23 56.6 -59 36           ~ 189 0

To bookmark this query, right click on this link: simbad:objects in 2018ApJ...852...99N and select 'bookmark this link' or equivalent in the popup menu