2006MNRAS.371.1983M


C.D.S. - SIMBAD4 rel 1.7 - 2020.02.25CET22:21:12

2006MNRAS.371.1983M - Mon. Not. R. Astron. Soc., 371, 1983-1991 (2006/October-1)

Discovery and analysis of three faint dwarf galaxies and a globular cluster in the outer halo of the Andromeda galaxy.

MARTIN N.F., IBATA R.A., IRWIN M.J., CHAPMAN S., LEWIS G.F., FERGUSON A.M.N., TANVIR N. and McCONNACHIE A.W.

Abstract (from CDS):

We present the discovery of three faint dwarf galaxies and a globular cluster in the halo of the Andromeda galaxy (M31), found in our MegaCam survey that spans the southern quadrant of M31, from a projected distance of ∼50 to ∼150kpc. Though the survey covers 57 deg2, the four satellites lie within 2° of one another. From the tip of the red giant branch (RGB), we estimate that the globular cluster lies at a distance of 631±58kpc from the Milky Way and along with a ∼100kpc projected distance from M31 we derive a total distance of 175±55kpc from its host, making it the farthest M31 globular cluster known. It also shows the typical characteristics of a bright globular cluster, with a half-light radius of 2.3±0.2pc and an absolute magnitude in the V band of M_V,0_= -8.5±0.3. Isochrone fitting reveals that it is dominated by a very old population with a metallicity of [Fe/H] ∼ -1.3. The three dwarf galaxies are revealed as overdensities of stars that are aligned along the RGB tracks in their colour-magnitude diagrams. These satellites are all very faint, with absolute magnitudes in the range -7.3 ≲ M_V,0_≲ -6.4, and show strikingly similar characteristics with metallicities of [Fe/H] ∼ -1.4 and half-light radii of ∼120±45pc, making these dwarf galaxies two to three times smaller than the smallest previously known satellites of M31. Given their faintness, their distance is difficult to constrain, but we estimate them to be between 740 and 955kpc which places them well within the virial radius of the host galaxy. The panoramic view of the MegaCam survey can provide an unbiased view of the satellite distribution of the Andromeda galaxy and, extrapolating from its coverage of the halo, we estimate that up to 45±20 satellites brighter than MV∼ -6.5 should be orbiting M31. Hence faint dwarf galaxies cannot alone account for the missing satellites that are predicted by Λ cold dark matter models, unless they reside in dark matter minihaloes that are more massive than the typical masses of 107Mcurrently inferred from their central radial velocity dispersion.

Abstract Copyright: 2006 The Authors. Journal compilation © 2006 RAS

Journal keyword(s): galaxies: dwarf - galaxies: formation - galaxies: individual: And XI - galaxies: individual: And XII - galaxies: individual: And XIII - galaxies: structure

Nomenclature: Table 1: And R (Nos XI to XIII) added. Table 1: [MII2006] GC N=1.

Simbad objects: 27

goto Full paper

goto View the reference in ADS

Number of rows : 27

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 NGC 147 GiG 00 33 12.120 +48 30 31.46   12.0 9.5     ~ 614 1
2 NAME Andromeda III G 00 35 22.7 +36 30 17     14.4     ~ 267 0
3 M 110 GiG 00 40 22.0544552438 +41 41 07.496294862   8.92 8.07     ~ 1195 1
4 M 31 G 00 42 44.330 +41 16 07.50 4.86 4.36 3.44     ~ 10711 1
5 NAME Andromeda I G 00 45 39.8 +38 02 28   13.9 12.7     ~ 300 0
6 NAME Andromeda XI G 00 46 20.0 +33 48 05     17.5     ~ 102 0
7 NAME Andromeda XII G 00 47 27.0 +34 22 29     18.3     ~ 103 0
8 NAME Martin-GC1 GlC 00 50 42.45 +32 54 58.7     15.50     ~ 43 1
9 NAME Andromeda XIII G 00 51 51.0 +33 00 16     18.1     ~ 103 0
10 NAME Andromeda IX G 00 52 53.0 +43 11 45     16.3     ~ 145 1
11 NAME Sculptor Dwarf Galaxy G 01 00 09.4 -33 42 32   9.79 8.6 8.81   ~ 1086 4
12 NAME Andromeda X G 01 06 33.70 +44 48 15.8     16.6     ~ 95 1
13 NAME Andromeda V G 01 10 17.1 +47 37 41     15.3     ~ 183 0
14 NAME Andromeda II G 01 16 29.8 +33 25 09     11.7     ~ 335 0
15 NAME Fornax Dwarf Spheroidal G 02 39 59.3 -34 26 57   9.02 7.4     ~ 1441 1
16 NAME Carina dSph G 06 41 36.7 -50 57 58   22.14 11.0 19.47   ~ 972 0
17 NAME Leo I dSph G 10 08 28.12 +12 18 23.4   11.3 10.0     ~ 1027 1
18 NAME Dwarf Elliptical Galaxy in Sex G 10 13 02.9 -01 36 53   12 10.4     ~ 684 0
19 NAME UMa I Galaxy G 10 34 52.80 +51 55 12.0     14.4     ~ 257 1
20 NAME Leo B G 11 13 28.13 +22 09 10.1   12.9 12.0     ~ 718 0
21 NAME CVn I dSph G 13 28 03.5 +33 33 21     13.1     ~ 242 1
22 NAME Bootes Dwarf Spheroidal Galaxy G 14 00 00.0 +14 30 00     12.8     ~ 321 0
23 NAME UMi Galaxy G 15 09 11.34 +67 12 51.7   13.60 10.6     ~ 1157 0
24 NAME Pisces II G 22 58 31.0 +05 57 09     16.3     ~ 204 0
25 NAME Andromeda VII GiG 23 26 31.7 +50 40 33   13.6 11.8     ~ 173 1
26 NAME Peg dSph GiG 23 51 46.4 +24 35 11   14.5 13.2     ~ 211 2
27 NAME Local Group GrG ~ ~           ~ 6806 0

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2006MNRAS.371.1983M and select 'bookmark this link' or equivalent in the popup menu


2020.02.25-22:21:12

© Université de Strasbourg/CNRS

    • Contact