1. Recovery of The Signal from the Epoch of Reionization
Tozzi & Illiev
2002

2. from the Epoch of Reionization ?
21cm H-line
@ hi-Z
SignalS
EoR
-> Dark Age
? Recovery ? of
?The Signal?
from the Epoch of Reionization ?
Tozzi & Illiev
2002

3. Roberston, Ellis, et al 2010, Nature, astroph/1011.0727
Identified Galaxy Population sufficient to ionize Universe by Z=7
Gradual reionization starting Z~20, completing Z~6 (WMAP)
most likely Dust-free, Metal-poor, high Escape-fraction
no need for BHs, exotic radiation source => X-rays

4. from the Epoch of Reionization ?
21cm H-line
@ hi-Z
SignalS
EoR
-> Dark Age
? Recovery ? of
?The Signal?
from the Epoch of Reionization ?
Tozzi & Illiev
2002

5. from the Epoch of Reionization ?
? Recovery ? of
?The Signal?
from the Epoch of Reionization ?
Tozzi & Illiev
2001
Pritchard & Loeb
2010
WMAP 2003

6. δTb: 21cm Brightness temperature
Cosmology
Astrophys.

7. The Global evolution of the Spin Temperature
Collisions
Ts -> Tkinetic
Radiation
Ts -> Tcmb
Ly Scattering
Loeb & Zaldarriaga 04, Baek et al , Thomas & Zaroubi 2010, Pritchard & Loeb 2010

8. 21cm Brightness Temp Simulations
150mK
50mK
Z=21
Z=17
100mK
30mK
Z=14
Z=11
Santos et al. 2010, see also Mesinger et al 2010

9. Roberston, Ellis, et al 2010, Nature, astroph/1011.0727
Growth of structure in 21cm Sky
… according to theory… (Barkana 2006)
Each
Frequency
Slice
Roberston, Ellis, et al 2010, Nature, astroph/

10. Schematic of Reionization…
dTB
High Neutral Fraction
Maximum fluctuation
Low Neutral Fraction
Good experimental technique… should bracket the period of max contrast

11. Extraction through the skewness
Iliev et al. 2006
Thomas et al. 2008
Harker et al. 2009

12. Schematic of Reionization…
dTB

13. Schematic of Reionization… Power Spectra of Faint Fluctuations
dTB
Z=15
Z=13
Z=18
Z=12
L = 2/
Furlanetto et al 2004

14. The signal + Foregrounds
Jelic et al. 2009, Shaver et al. 99, Di Matteo et al, Santos et al 05, Gleser et al 09

15. The signal + Foregrounds
Assessment of foregrounds
Bernardi et al, 2010 … WSRT study
Paciga et al, 2010 GMRT study
Brentjens Faraday Rotation in diffuse emission on size scales of EoR fluctuations + calibration errors
RM=-50 to +100, located within 1kpc.

16. Recovery Strategies for hi-Z HI signals…
Power Spectra,
Freq-bracket,
Cross-Correlation(QSO,gals?),
Global Signature… (using arrays for calibration and
redundancy)
Mapping individual features - … SKA project

17. Centaurus A

18. Centaurus A

20. Spin Temperature issues
In case the spin temp. is of the order the CMB temp.
or smaller an absorption signature is expected at high
redshifts.
Thomas & Zaroubi 2010
See also Baek et al. 2010

21. EoR & Dark Ages: Key Science Questions
Typical size of ionized regions as a function of redshift.
Thermal history of the IGM
Influence of the EoR on subsequent structure formation and evolution
Do we know that reionization is photon starved? Is this a strong constraint of reionization?
Cosmology:
PS, high-order statistics, cosmological PS, primordial non-Gaussianity, constrain DM candidates, Alcock Paczynski test, ....
Global Evolution of the EoR. How did reionization proceed?
What are the first sources?
Stars: How did they form?
The role of H2 & HI cooling.
Pop.II vs Pop III
BH + mini-QSOs
DM decay or annihilation.
Topology of the IGM during the EoR.
When reionization became complete?
Individual Halos.

22. 1. Imaging: an Example Z21 Diam integ 6.5 0.3 km 2 hr integ (LFD)
5 year hr b

23. 3. Faint Brightness Fluctuations:
Survey Area has N independent synthesized
beam areas with RMS fluctuation
<Tb2>1/2
Noise level:
Uncertainty in Estimate of <Tb2>1/2 is
20 deg

24. HST nature result X
compare to texture in IGM X
equation containing cosmo and astro X
deviation of Tkin from Tcmb and when Tspin ->
my model of the signal X
skewness X
?fluctuations dependence on filling factor?
punch line… from theorists - use Eqn slide again
assessment of foregrounds
Bernardi et al, 2010 … WSRT study
Paciga et al, 2010 GMRT study
Brentjens - cross check ang-scale against frequency periodicity=> size scales of EoR fluctuations
RM=-50 to +100, located within 1kpc.
60MHz Z=23 => sigma=20mK
emphasize Freq-bracket, Cross-Correlation(QSO,gals?)
global signal but using arrays for calibration and
redundancy