Transcript Presentazione di PowerPoint

What did today’s
passive galaxies do in
the past
Bianca Poggianti
INAF – Osservatorio Astronomico Padova
T. Bridges
D. Carter
N. Kashikawa
Y. Komiyama
B. Mobasher
S. Okamura
B.M. Poggianti
M. Yagi
Post-starburst galaxies
and the intracluster
medium
in the Coma cluster
B and R
with Japanese mosaic
CCD camera on WHT
Spectra for 300 members
with WYFFOS/WHT, 69 A res., 3600-6600 A
EW(Hdelta) > 3 A
Faint k+a in Coma
Poggianti et al. 2004
Red and blue
Poggianti,Bridges,Komiyama et
al. 2004
X-ray from Neumann et al.
2003
all dwarfs
strong, young k+a’s
weak, older k+a’s
K+a galaxies and substructure in
Coma
1.
The position of faint post-starburst galaxies in Coma relative
to X-ray substructure strongly suggestive:
The recent infall of these galaxies onto the cluster and the
consequent interaction with the hot ICM were the cause for
the abrupt change in their star formation histories
“CAUGHT IN THE ACT”
2. k+a spectrum (=truncation of SF) related to cluster
3. The impact with the ICM can have a strong effect on the SFH
of a galaxy. The effect is FAST. (Vollmer et al. 99,00,01, Quilis et al.
00, Abadi et al. 99)
4. It isn’t easy to pinpoint relation between gal. evol. and
substructure, ‘cause it is not easy to identify substructure, i.e.
reconstruct the infall history of a cluster
Post-starburst/post-starforming (k+a) galaxies in the
MORPHS sample of 10 clusters at z=0.4-0.5
Dressler et al. 1999, Poggianti et al. 1999, Dressler et al. 2004
Observing
late star-forming faint
galaxies becoming
“dwarf ellipticals”
About 10% of the dwarf
cluster population
Caldwell et al.’s works
Tran et al. 2003
Comparison
Coma - clusters at z=0.4-0.5
Downsizing effect:
k+a’s: a luminous phenomenon at z=0.5 and a faint one at z=0?
probably reflecting a change in the SF properties of the
infalling galaxies
evolution of the MAXIMUM LUMINOSITY of k+a galaxies
in clusters – another evidence for downsizing
going to lower redshifts, the maximum luminosity/mass of
galaxies with significant SF activity progressively decreases –
active star formation in low mass galaxies seems to be (on
average) more protracted than in massive galaxies
Well-known dependence on galaxy mass/luminosity:
the more massive, the oldest
both in clusters –
Smail et al. 1998
Bower et al. 1999
Halliday 1999
Kajisawa et al. 2000
Nakata et al. 2001
Kodama & Bower 2001
Poggianti et al. 2001a,b (ages and metallicities as a fn. of the galaxy luminosity)
De Propris et al. 2003
De Lucia et al. 2004
Kodama et al. 2004
and in the field –
Cowie et al. 1996, Kauffmann et al. 2003, Bell et al. 2003
The questions
1.
Was the SB induced by the impact with the ICM? Possibly
2.
Could it be strangulation?
No
3. Is the origin of k+a galaxies in distant clusters the same as of
k+a’s in Coma?
?
4. Are there k+a dwarf galaxies in distant clusters?
? Ongoing VLT
project
5. k+a’s in the field at low z are dwarf galaxies too?
Giant galaxies known
6. Is this inconsistent with hierarchical modeling+semianalytics?
It depends on SFE assumptions
7. What is the origin of the downsizing effect?
SF in low mass galaxies more protracted on average than in
massive galaxies: most likely “intrinsic”, not environmental
The ESO Distant Cluster Survey
Study evolution of clusters and cluster galaxies
in a uniform imaging and spectroscopic database
over ½ of the Hubble time
S. White ( MPA-Garching, D )
A. Aragón-Salamanca ( Nottingham, UK )
R. Bender ( Munich, D )
P. Best ( ROE, Scotland )
M. Bremer ( Bristol, UK )
S. Charlot ( MPA, D & IAP, F )
D. Clowe ( Bonn, D)
J. Dalcanton ( U.Washington, USA )
B. Fort ( IAP, F )
P. Jablonka ( OPM, F )
G. Kauffmann ( MPA, D )
Y. Mellier ( IAP, F )
R. Pello ( OMP, F )
B. Poggianti ( Padova, I )
H. Rottgering ( Leiden, NL )
P. Schneider ( Bonn, D )
D. Zaritsky ( U. Arizona, USA )
M. Dantel ( OPM, F )
G. De Lucia ( MPA, D )
V. Desai ( U. Washington, USA )
C. Halliday ( Padova, I )
B. Milvang-Jensen ( MPE, D )
S. Poirier ( OPM, F )
G. Rudnick ( MPA, D )
R. Saglia ( Munich, D )
L. Simard ( U. Victoria, C )
EDisCS – ESO Distant Cluster Survey
10 + 10 cluster fields selected from the Las
Campanas Distant Cluster Survey (Gonzales et al.
2001):
• Deep imaging: VRIJK at z~0.8, BVIK at z~0.5
(11n FORS2 + 20n SOFI)
• Spectroscopy: at least 4 FORS2 masks at long
exposure to get spectra to I~23 (z~0.8) or 22
(z~0.5) (22n FORS2)
• HST/ACS imaging for 10 most distant clusters (80
orbits)
• WFI 3-color imaging for all 20 fields (84hr WFI)
ESO LP allocation: 36n VLT/FORS2 + 20n NTT/SOFI
EDisCS Imaging
10 “high-z” fields in VRIJK, 10 “low-z” fields in BVIK
CL1354.1-1231
CL1054.4-1245
z=0.76
CL1037.5-1243
z=0.75
z=0.58
CL1232.3-1250
CL1202.4-1224
z=0.54
z=0.42
EDisCS – ESO Distant Cluster Survey
10 + 10 cluster fields selected from the Las
Campanas Distant Cluster Survey (Gonzales et al.
2001):
• Deep imaging: VRIJK at z~0.8, BVIK at z~0.5
(11n FORS2 + 20n SOFI)
• Spectroscopy: at least 4 FORS2 masks at long
exposure to get spectra to I~23 (z~0.8) or 22
(z~0.5) (22n FORS2)
• HST/ACS imaging for 10 most distant clusters (80
orbits)
• WFI 3-color imaging for all 20 fields (84hr WFI)
ESO LP allocation: 36n VLT/FORS2 + 20n NTT/SOFI
Morphology  HST
CL1037.5-1243
z=0.58
CL1216.4-1201
z=0.79
EDisCS – ESO Distant Cluster Survey
10 + 10 cluster fields selected from the Las
Campanas Distant Cluster Survey (Gonzales et al.
2001):
• Deep imaging: VRIJK at z~0.8, BVIK at z~0.5
(11n FORS2 + 20n SOFI)
• Spectroscopy: at least 4 FORS2 masks at long
exposure to get spectra to I~23 (z~0.8) or 22
(z~0.5) (22n FORS2)
• HST/ACS imaging for 10 most distant clusters (80
orbits)
• WFI 3-color imaging for all 20 fields (84hr WFI)
ESO LP allocation: 36n VLT/FORS2 + 20n NTT/SOFI
Halliday et al. 2004
A&A in press
(astro-ph 0408071)
Halliday et al. 2004 --- cl1216 at z=0.8
Halliday et al. 2004
(astro-ph 0408071)
Halliday et al. 2004 (astro-ph 0408071)
Halliday et al.
2004 (astro-ph
0408071)
De Lucia et al. 2004, ApJL 610, L77
Data from Terlevich et
al. (2001)
De Lucia et al. 2004
ApJ Letter
Smail et al. 1998; Kajisawa et al. 2000,
Nakata et al. 2001, Kodama et al. 2004
-- Defining as “faint” galaxies 0.4 < L/L* < 0.1 (5σ
detection limit), the luminous-to-faint ratio on the red
sequence is 0.34±0.06 in Coma and 0.81±0.18 in
EDisCS
-- The effect is seen also in the single-cluster
distributions, despite of the variety of cluster
properties: such a deficit may be a universal
phenomenon in clusters at these redshifts
A deficiency of red galaxies at faint magnitudes
compared to Coma
-- A synchronous formation of stars in all red
sequence galaxies is ruled out, and the comparison
with Coma quantifies the effect as a function of
galaxy magnitude
De Lucia et al. 2004 ApJL
-- A large fraction of the red faint galaxies has moved
onto the red sequence relatively recently, having their
SF presumably ended at z<0.8
Stay tuned on EDisCS……..
Stellar population analysis of cluster galaxy spectra
(see Halliday’s poster)
Tully-Fisher relation of cluster and field galaxies up to z~0.8
(see Milvang-Jensen’s poster)
Metallicity-luminosity relation of star-forming galaxies
(see Moustakas’s poster)
Stay tuned on EDisCS…soon to come
Evolution of galaxy masses and IR phot.
(Aragon-Salamanca et al.)
Weak lensing mass reconstructions
(Clowe et al.)
HST galaxy morphologies in clusters at 0.8 – Evolution of galaxy Hubble types,
of merger rates and properties, and of the morphology-density relation
(Desai et al.)
Differences between group and cluster galaxies up to z~0.8
(Halliday et al.)
The spectroscopy of the remaining 14 clusters
(Milvang-Jensen et al.)
Star formation and evolutionary histories in clusters from z=0.8
(Poggianti et al.)
The Fundamental-Plane of early-type galaxies (Saglia et al.)
Bulge-to-disk decompositions and early-type galaxy fractions
(Simard et al.)
Presentation of the survey and of the optical photometry
(White et al.)………………………
Halliday et al. 2004
Tran et al. 2003 (see Tran’s talk)
EDisCS is an international project involving 26 astronomers from 7 countries.
The original proposal was submitted by the following group of co-investigators :
S. White ( MPA-Garching, D ) - Principal Investigator A. Aragón-Salamanca ( Nottingham, UK )
R. Bender ( Munich, D )
P. Best ( ROE, UK )
M. Bremer ( Bristol, UK )
S. Charlot ( MPA, D & IAP, F )
D. Clowe ( Bonn, D)
J. Dalcanton ( U.Washington, USA )
B. Fort ( IAP, F )
P. Jablonka ( OPM, F )
G. Kauffmann ( MPA, D )
Y. Mellier ( IAP, F )
R. Pello ( OMP, F )
B. Poggianti ( Padova, I )
H. Rottgering ( Leiden, NL )
P. Schneider ( Bonn, D )
D. Zaritsky ( U. Arizona, USA )
Others actively involved in the project currently include:
M. Dantel ( OPM, F )
G. De Lucia ( MPA, D )
V. Desai ( U. Washington, USA )
C. Halliday ( Padova, I )
B. Milvang-Jensen ( MPE, D )
S. Poirier ( OPM, F )
G. Rudnick ( MPA, D )
R. Saglia ( Munich, D )
L. Simard ( U. Victoria, C )
cl1054-11
z=0.70
EDISCS - Desai et al. in preparation
Ground based and HST images
Cl1037
- Desai et al. in prep.
Cl1037.5-1243