Clusters of galaxies Virgo cluster Abell 1689

28 Pages·2013·5.22 MB·English

Clusters of galaxies
Virgo cluster
Abell 1689
Perseo cluster
Coma cluster
Deep field SDSS
H-R diagram
Hertzsprung (1873-1967)

Russell (1877-1957)
the colour-magnitude relation
Scaling relations:
Showing two different properties of the galaxies as their lumonisity (or magnitudes)
against their colours we obtain a distrution of points in the plane not uniform
(Baldry 2006):
SDSS, galaxias
a z < 0.1
• “red sequence”

• “blue cloud”
Bimodalilty in colours is present up to z≈1

(Strateva et al. 2001; Blanton et al. 2003; Baldry et al. 2006)
The Colour-Magnitud Relation (CMR):
Fornax cluster
Hilker et al. (2003)
Hydra I
cluster
(Misgeld et al.
2008)
Abell 1644, 1069
There is evidence of the break in
Vaucoleurs et al. (1961), Tremonti
et al. (2004), Baldry et al. (2004),
Ferrarese et al. (2006), Boselli et al.
(2008), Metcalfe, Godwin & Peach
(1994)
Virgo cluster (SDSS)
Janz & Lisker 2009
Hydra I cluster
(Misgeld et al.
2008)
Motivation:

The CMR constitutes an excelent tool to constrain galaxy formation
models since galactic evoution is evidenced through the relation

What are the physical processes involved in the development of the
CMR of cluster galaxies?

How can we explain the behavior of the bright end?
Hybrid Model of Galaxy
Formation
N-body Semi-analytical
Simualtions model of galaxy
Formation (SAG)
Semi-Analytic model of Galaxy Formation (SAG)
Simulated clusters (Dolag et al. 2005):

 Originally extracted from a DM-only
simulation with a box size of 479 h−1 Mpc

C15: 3 clusters
 The Lagrangian regions surrounding
M (z=0) ~ 1015 h-1 M
the selected clusters have been 
resimulated at higher mass and force
resolution using the ’zoomed initial
conditions’ technique (Tormen et al. 1997)
C14: 5 clusters

M (z=0) ~ 1014 h-1 M

9 −1
M = 1.13× 10 h M
DM o
Ω = 0.3, Ω = 0.7,Ω = 0.13
m Λ b
GADGET- 2
Γ= 0.21, σ = 0.9 (Springel et al. 2005)
8
−1 −1
H = 100 km s Mpc , h= 0.7
0
M   M (M(i)  M(i)  M(i) )
hot b vir star cold BH
i
3 kT (r)
g
t (r) 
cool 2 m n2(r)(T,Z)
p e
dM dr
cool  4r2 cool
cool
dt dt
The model is calibrated to reproduce
simultnaneously several galactic properties as the
STARS n
dM  V  M
  vir  cold
LF, the MBH, the CMR, morpholgy ratios, etc 
4  E dt 220kms1 t
M   SNCC SNCC M  
reheat 3 V2  dyn
vir
Low mass
stars
SN CC
SN Ia