Satellite systems around galaxies in hydrodynamic simulations

被引:83
作者
Libeskind, Noam I.
Cole, Shaun
Frenk, Carlos S.
Okamoto, Takashi
Jenkins, Adrian
机构
[1] Univ Durham, Dept Phys, Sci Labs, Durham DH1 3LE, England
[2] Natl Astron Observ, Mitaka, Tokyo 1818588, Japan
关键词
galaxies : formation; galaxies : haloes; galaxies : luminosity function; mass function; galaxies : spiral; cosmology : theory;
D O I
10.1111/j.1365-2966.2006.11205.x
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We investigate the properties of satellite galaxies formed in N-body/SPH simulations of galaxy formation in the Lambda CDM cosmology. The simulations include the main physical effects thought to be important in galaxy formation and, in several cases, produce realistic spiral discs. In total, a sample of nine galaxies of luminosity comparable to the Milky Way was obtained. At magnitudes brighter than the resolution limit, M-V=-12, the luminosity function of the satellite galaxies in the simulations is in excellent agreement with data for the Local Group. The radial number density profile of the model satellites, as well as their gas fractions also match observations very well. In agreement with previous N-body studies, we find that the satellites tend to be distributed in highly flattened configurations whose major axis is aligned with the major axis of the (generally triaxial) dark halo. In two out of three systems with sufficiently large satellite populations, the satellite system is nearly perpendicular to the plane of the galactic disc, a configuration analogous to that observed in the Milk Way. The discs themselves are perpendicular to the minor axis of their host haloes in the inner parts, and the correlation between the orientation of the galaxy and the shape of the halo persists even out to the virial radius. However, in one case the disc's minor axis ends up, at the virial radius, perpendicular to the minor axis of the halo. The angular momenta of the galaxies and their host halo tend to be well aligned.
引用
收藏
页码:16 / 28
页数:13
相关论文
共 82 条
[1]   N-BODY SIMULATIONS OF GALAXY CLUSTERING .1. INITIAL CONDITIONS AND GALAXY COLLAPSE TIMES [J].
AARSETH, SJ ;
GOTT, JR ;
TURNER, EL .
ASTROPHYSICAL JOURNAL, 1979, 228 (03) :664-683
[2]   Simulations of galaxy formation in a cold dark matter universe. II. The fine structure of simulated galactic disks [J].
Abadi, MG ;
Navarro, JF ;
Steinmetz, M ;
Eke, VR .
ASTROPHYSICAL JOURNAL, 2003, 597 (01) :21-34
[3]   The locations of satellite galaxies in a ΛCDM universe [J].
Agustsson, Ingolfur ;
Brainerd, Tereasa G. .
ASTROPHYSICAL JOURNAL, 2006, 650 (02) :550-559
[4]  
ASHOORIOOON A, 2006, UNPUB HUTP
[5]  
AZZARO M, 2006, UNPUB MNRAS
[6]   Internal alignment of the halos of disk galaxies in cosmological hydrodynamic simulations [J].
Bailin, J ;
Kawata, D ;
Gibson, BK ;
Steinmetz, M ;
Navarro, JF ;
Brook, CB ;
Gill, SPD ;
Ibata, RA ;
Knebe, A ;
Lewis, GF ;
Okamoto, T .
ASTROPHYSICAL JOURNAL, 2005, 627 (01) :L17-L20
[7]   Internal and external alignment of the shapes and angular momenta of ACDM halos [J].
Bailin, J ;
Steinmetz, M .
ASTROPHYSICAL JOURNAL, 2005, 627 (02) :647-665
[8]   Can the faint submillimetre galaxies be explained in the cold dark matter model? [J].
Baugh, CM ;
Lacey, CG ;
Frenk, CS ;
Granato, GL ;
Silva, L ;
Bressan, A ;
Benson, AJ ;
Cole, S .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2005, 356 (03) :1191-1200
[9]   The effects of photoionization on galaxy formation -: I.: Model and results at z=0 [J].
Benson, AJ ;
Lacey, CG ;
Baugh, CM ;
Cole, S ;
Frenk, CS .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2002, 333 (01) :156-176
[10]   The effects of photoionization on galaxy formation - II. Satellite galaxies in the Local Group [J].
Benson, AJ ;
Frenk, CS ;
Lacey, CG ;
Baugh, CM ;
Cole, S .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2002, 333 (01) :177-190