P bi Hi h U i
Probing High‐z Universe with GRB
ith GRB
●
GRB Afterglows as Cosmic Lighthouses
 detect highest‐z GRBs AG at their brightest phase
●
GRB as the tracer of high‐z star‐formation
What are the GRB precursors?
p
Are GRBs unbiased or biased tracers of SF?
How they probe the formation of very massive stars?
yp
y
●
GRB as cosmological standard candle
GRB as cosmological standard candle
Outline
1. GRB Hosts and High‐z Galaxies
2. Massive‐star formation at high‐redshift
Does IMF change?
Does IMF change? 3. Probing Star‐Formation at z=7‐20,
“That is your WISH, isn’t it?”
GRB Hosts: SFR/Stellar Mass
/
GRB hosts
GRB hosts
× galaxies
GRB @ z=0‐6.3
Savaglio et al. 2008
et al 2008
also, e.g., Jakobsson et al. 2005
GRB Hosts: UV Luminosityy
UV Luminosity Distribution of GRB (w/opt. AG) Hosts
y
( / p
)
(7 hosts detected/15 at z> 2)
GRB
~General
General Gal
Population
Chen et al. 2009
GRB Hosts: Morphology
p
gy
Morphology of GRB hosts
Morphology
of GRB hosts
~exp profile , large irregularity GRBs
Majority
at z = 1‐2
Re
Wainwright et al. 2007
MB
Similar Size‐Luminosity Relation with the general sample?
Conselice et al. 2005
et al 2005
Large concentration at high‐z?
GRB Hosts: Metallicityy
Metallicity distribution: scattered, ~general
distribution: scattered ~general
Collapser
C
ll
th h ld
threshold
Z~0.3Zsun
ALS
GRBs
Fynbo et al. 2006
Erb et al.
GRB
GRB Savaglio et al. 2008
also see Chen et al. 2009
GRB Hosts (long burst, w/OA)
● SFR
SFR, M*, UV Luminosity Distribution M* UV L i it Di t ib ti
… ~ Random Galaxy Population
e.g., Chen et al. 2009, Savaglio et al. 2008, Wainwright et al. 2007
● Morphology
… similar with the general? larger concentration?
e g Wainwright et al 2007 / Concelice et al. 2005
e.g., Wainwright et al. 2007 / Concelice
et al 2005
● ISM Metallicity
… <0.3 Z
<0 3 Zsun (Collapser model threshold)
model threshold)
but ~ Unbiased Population at z>2
e g Fynbo et al.2006, Price et al. 2007
e.g., Fynbo
et al 2006 Price et al 2007
Dust in GRB Line of Sight
g
Peyley
ey ey et
et al. 2009
a 009
Prochaska et al. 2007
GRB (z=3 03) Av=3 2
GRB (z=3.03) Av=3.2
GRB as a tracer of high‐z star‐formation
g
Unbiased Tracers? GRB rate vs UV SFR
Unbiased Tracers? GRB rate vs. UV SFR
Cosmic SF History
GRB
LBGs
GRB rate,
GRB
rate
Normalized to SFR
at z=1‐4 Kistler et al. 2008
But see Jakobsson et al. 2005
● GRB Hosts seems GRB Hosts seems
distributed over the general population ..But this is reasonable if GRBs are certain‐type, but f
frequent population of massive stars.
t
l ti
f
i
t
● GRB seems to be Unbiased
GRB seems to be Unbiased Tracers Tracers
of Star Formation?

Massive star formation at High Redshift
Some Evidence of Flat/Top‐Heavy IMF / p
y
In Local and High‐z Universe NGC3603
Stella Mass Function in NGC3603
Stella Mass Function in NGC3603
VLT+NACO
Harayama et al. 2007
‐ Stellar mass segregation is observed
‐ yet, the IMF for the entire cluster is still flat yet the IMF for the entire cluster is still flat
x=‐0.74 ( > ‐1.35, Salpeter)
Large L/Mdyn
Large L/M
of a Cluster (F) in M82
(F) in M82
d of a Cluster
Salpeter (Kroupa) IMF
 L/Mdyn ~ 7‐12 L
7‐12 Lsun/Msun
(for 60Myr age)
Observed 42±10 Lsun/Msun
Observed 42±10
M82
Bastian et al. 2007
Change of Mdyn/L along the time: Cl t Elli ti l Fundamental Plane at z=0.1‐0.8
Cluster Ellipticals
F d
t l Pl
t 0108
Fundamental Plane
Evolution
Changes in M/L
I
Is more consistent
it t
with flat (x=0.3) IMF
Van Dokkum 2008
Δ(U‐V) ~ Age,
Δ(U
V) ~ A
Not depending as much on IMF slope as on age
Cosmic SF History and IMF
Cosmic SF History and IMF
Inconsistent Normalization of
l
f
Cosmic SFR and Stellar Mass History
Star Formation Rate
Integration
Uncertainties:
‐ High‐z Mass Function
‐ IMF
‐ Field‐to‐Field Variance
Stellar Mass Density
Stellar Mass Density
Hopkins and Beacom 2006
MOIRCS Deep Survey (MODS) J, H, Ks, (NB119)
Wide
K~22.5 (Vega)
Deep
K~23 6 (Vega)
K~23.6 (Vega)
BVIzJHK IRAC ch1‐4
GOODS‐N
P.I. Takashi Ichikawa
Cosmic SF Rate Density and Stellar‐Mass Density Our Results
Our Results
Kajisawa et al. 2009 MOIRCS Deep Survey Cosmic SF Rate Density and Stellar‐Mass Density Stellaar Mass Densiity
Change of IMF needed
Change
of IMF needed
More contribution by 1.5‐4Msun stars at high‐z
Fardal et al. 2006
Redshift
Large Equivalent Width of Lyα Emitters
Lyα Equivalent Width
Equivalent Width
~ Lyα Line Luminosity T C
Top
h
heavy iIMF x=0.5
05 L
/ Adj
/ Adjacent Continuum Luminosity per wavelength
i i
l
h
~240Å
~ Number of Ionizing Photon / Non‐Ionizing Photon
(for Photo Ionization)
S l t IMF x=2.35
Salpeter
2 35
Constant Continuous SF, 1/20 Zsolar
Ml=1 Msun , Mu=120 Msun
Malhotra et sl. 2002; Charlot and Fall 1993
Shimasaku+06
Z=5.7 LAE
SSA22 z=3.1
SSA22 z
3.1 LAE Sample
LAE Sample
General Fields
SSA22
SXDS
SDF
1391LAEs
589LAEs
Black points: LAEs
Bl
k i t LAE
Green lines: contour of average number density of LAEs
Gray Region: masked region to avoid some bright stars
Large Equivalent Width of Lyα Emitters
Large Equivalent Width of Lyα
Nakamura 2010
Shaded area: lower limit
Large Equivalent Width of Lyα Emitters
Large Equivalent Width of Lyα
Including the toal
Lyα and UV
and UV
Lyα
UV
Nakamura 2010
Very Blue UV Slop of z=7 Galaxies
e y ue U S op o
Ga a es
Fλ
β
~ λλ
（UV wavelength）
Bluer in
Bluer
in
◆ higher‐z galaxies
◆ fainter galaxies
f i t
l i
β
How to make β ~ ‐3
Very Metal Poor Hot Stars
y
Large Escape Fraction
M(UV)
Bouwens et al. 2010 High‐z Type‐IIn
g
yp
Super Novae
p
More than a few Type‐IIn SNe
detected at z~2
Cooke et al. 2009
k
l
Epoch 1
Epoch 2
Cooke et al. (2009) argues that
The current rate is still consistent with
Salpeter like IMF though small statistics
Salpeter‐like IMF, though small statistics
Observed
Subtracted
Massive Star Formation at High Redshift
Massive Star Formation at High Redshift
Evidence suggesting enhanced massive‐star formation is being observed
formation is being observed.
More direct constraints needed ‐ Colors of Very High
Colors of Very High‐zz Galaxies
Galaxies
POPII/III stars toward z=20
‐ GRB / Type‐IIn
GRB / T
II SNe, SN
tracers of massive stars at intermediate and high redshift
P bi th V E l U i
Probing the Very Early Universe:
That is our WISH
That is our WISH WISH
Wide-field
Wide
field Imaging Surveyor for High
High-Redshift
Redshift
超広視野初期宇宙探査衛星
WISH W ki G
WISH Working Group
http://www.wishmission.org/en/index.html
M31 Phot: R.Gendler
WISH WG under JAXA/ISAS Science Committee
R&D On‐Going
Toru Yamada, Chihiro
d h h Tkokku
k kk (Tohoku University)
( h k
)
Ikuru Iwata, S.Tsuneta, T.Morokuma, T.Kodama, Y.Komiyama
k
d
(
(NAOJ)
)
H.Matsuhara, T.Wada, Y.Oyabu (JAXA/ISAS)
K.Ohta, K.Yabe
h
b (Kyoto University)
(
i
i )
M.Doi, N.Yasuda (University of Tokyo)
NK
N.Kawai
i (TiTEC)
A.Inoue (Osaka Sangyo University)
Y Ik d (Photocoding)
Y.Ikeda
(Ph
di )
T.Iwamura (M.R.J)
CG of a 1st –gen galaxy, by Toru Yamada
Cosmic Microwave Background (CMB)
Universe: Neutral
WISH
First‐Generation
Galaxies Galaxies
Ultimate Frontier
of Galaxies
Universe: Ionized
Subaru
VLT
…………
Hubble Space Telescope
Hubble Space Telescope
WISH Science Goals
WISH Science Goals
[1] Discovery of the First Generation Objects
(galaxies SMBH
(galaxies,
SMBH, and GRB)
and Study Galaxy Formation at EoR.
[2] Study of the expansion history of the universe
properties
p
of dark energy
gy by
y using
g type-Ia
yp
and p
supernovae luminosity at rest-frame
NIR(i-band) wavelength
[3] Extensive study of galaxy formation and
evolution utilizing the unique wide-area
NIR observations
WISH Specifications Quick Summary
WISH Specifications Quick Summary
Pi
Primary Mirror Diameter
Mi
Di
t 1.5m
1 5m
Wavelength Coverage
g
g 1‐5μm
μ
Image Quality achieving diffraction limit to the FoV edge
at 1‐5 μm
at 1‐5 μm
Spatial Sampling 0.15”/18μm (optimized at 1.5μm )
Limiting Magnitude ~28 AB/10‐20h ~20nJy (3sigma)
Camera Field of View ~１０００acmin2
Orbit SSE‐L2
Launcher Japanese HIIA (fit to the Dual Launch)
WISH Optical Layout and the Focal Plane Layout
Three Mirror system,
Very FLAT FP
Diffraction limit ff
l
at 1‐5μm Current Plan
Current
Plan
For the FP Layout
WISH 5 Years Survey Plan
y
S
Surveys
A
Area
D h
Depth
N
Note
Ultra Deep
Ultra Deep
100 deg2
100 deg2
~28AB
28AB
ZZ~10‐17
10 17
Multi‐band
~10 deg2
~28
Z~8‐10
Ultra wide
~1000 deg2
~25
QSO,WL
Extreme
~1 deg2
~29‐30
Faint End
WISH is the survey dedicated mission
Survey speed 2X of JWST w/ φ 0 2” aperture photometry
Survey speed 2X of JWST w/ φ=0.2” aperture photometry
½X Point Sources E pected N mbers
Expected Numbers
Number / 1 deg2
Expected Numbers
No Evol.
No Evolution from z=7
By Iwata, Yabe
for WISH team extrapolation
Semi‐analytic
Kobayashi, M.
y
For WISH