Recovery of The Signal from the Epoch of Reionization Tozzi & Illiev 2002
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
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
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
from the Epoch of Reionization ? ? Recovery ? of ?The Signal? from the Epoch of Reionization ? Tozzi & Illiev 2001 Pritchard & Loeb 2010 WMAP 2003
δTb: 21cm Brightness temperature Cosmology Astrophys.
The Global evolution of the Spin Temperature Collisions Ts -> Tkinetic Radiation Ts -> Tcmb Ly Scattering Loeb & Zaldarriaga 04, Baek et al. 2010, Thomas & Zaroubi 2010, Pritchard & Loeb 2010
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
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/1011.0727
Schematic of Reionization… dTB High Neutral Fraction Maximum fluctuation Low Neutral Fraction Good experimental technique… should bracket the period of max contrast
Extraction through the skewness Iliev et al. 2006 Thomas et al. 2008 Harker et al. 2009
Schematic of Reionization… dTB
Schematic of Reionization… Power Spectra of Faint Fluctuations dTB Z=15 Z=13 Z=18 Z=12 L = 2/ Furlanetto et al 2004
The signal + Foregrounds Jelic et al. 2009, Shaver et al. 99, Di Matteo et al, Santos et al 05, Gleser et al 09
The signal + Foregrounds Assessment of foregrounds Bernardi et al, 2010 … WSRT study Paciga et al, 2010 GMRT study Brentjens 2010 - Faraday Rotation in diffuse emission on size scales of EoR fluctuations + calibration errors RM=-50 to +100, located within 1kpc.
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
Centaurus A
Centaurus A
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
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.
1. Imaging: an Example Z21 Diam integ 6.5 0.3 km 2 hr integ (LFD) 13 0.56 32 5 year 17 0.72 114 24 1.0 500 hr b
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
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. 3000K @ 60MHz Z=23 => sigma=20mK emphasize Freq-bracket, Cross-Correlation(QSO,gals?) global signal but using arrays for calibration and redundancy