Micro
wave
Backg
round
Image fromSpace TelescopeScience Institute
What reionizedWhat reionizedthe universe?the universe?
Searching for Lyman Beyond Reionization
Betsy Barton (UC Irvine)
Recent reionization results
• Wilkinson Microwave Anisotropy Probe (WMAP):
– Reionization begins at 14 < z < 20 (Kogut et al. 2003)
• Becker et al. (2001); Djorgovski et al. (2001); Fan et al. (2002):
– Absorption systems and Gunn-Peterson troughs in distant quasar spectra
– Reionization ends near z ~ 6
• Fan et al. (2001):
– quasars not enough to reionize universeSTAR-FORMING GALAXIES!
(see Tinsley 1973)
How can we find these galaxies?
Cosmological hydrodynamic simulations form “tiny” early seed galaxies
(Davé, Katz, & Weinberg)
z=8 Ly
star formation
cooling radiation
Cosmological hydrodynamic simulations: the star formation history of the universe
redshift
glo
bal
sta
r fo
rmat
ion
rat
e
(Springel &Hernquist 2003)
Peak is near z=5
rate significantat extremely high redshifts
Finding “holes” in the night sky
Atmospheric lines dominate
At higher spectral resolution, observe between them
Window at z=8.227
Narrow-bandfilter (R=125)
Noise down byfactor of >10 from other Gemini/NIRInarrow-bandfilters
transmissiontransmission
skyskyemissionemission
The Production and Escape of High-redshift Lyman- Photons
{{
{{stellar initialstellar initialmass functionmass function
star formation ratestar formation rate
penetration through penetration through intergalactic mediumintergalactic medium
escape ofescape ofionizing andionizing andLyLy photons photons
partially neutral IGM(above z ~ 6.2)
Adopted Lyman scenarios
ScenarioIMF
(MO)
Metallicity
(ZO)fIGM fesc fLy
Optimistic 300-1000 0 1.0 0.35 2.1 x 1043
Plausible 50-500 0 0.25 0.1 6.4 x 1042
Heavy Salpeter 1-500 10-5 0.25 0.1 1.8 x 1042
Salpeter 1-100 0.2 0.25 0.1 7.3 x 1041
Lyman Luminosity Function
8m8m30+ hrs30+ hrs
Models: Bartonet al. (2004)
Data: varioussources compiledin Santos et al. (2004)
“optimistic” scenario simulation
48 hour obs.1.122m20% throughputR=125 filter0.35-arcsec seeing
Springel & Hernquist (2003) model
(Barton et al. 2004)
z=8.2 galaxiesz=8.2 galaxies
10 10 hh-1-1 comoving Mpc=5.4 arcmin comoving Mpc=5.4 arcmin
Narrow-band filter
Hubble Deep Field
[OII] line emission at z=2.01, 15 hours with Gemini/NIRI
The Next Steps: FLAMINGOS 2 and MOSFIRE
Keck MOSFIRE:
6.2’ FOV
Gemini-SouthFLAMINGOS 2:
6.1’ FOV
F2T2F2T2An engineering prototype for the JWST Tunable Filter
Imager… F2T2 will be fed by a multi-conjugate adaptive optics system and be a facility-class instrument on
Gemini next year.
An engineering prototype for the JWST Tunable Filter Imager… F2T2 will be fed by a multi-conjugate adaptive
optics system and be a facility-class instrument on Gemini next year.
The F2T2 TeamBob
AbrahamU. Toronto
Steve EikenberryU. Florida
Nick RainesU.Florida
Jeff JulianU.Florida
Betsy BartonUC Irvine
Dave LoopHIA, Victoria
Al ScottCOMDEV
JD SmithU.Arizona
David Crampton
HIA, Victoria
Joss Bland-Hawthorn
AAO
Mike GladdersU.Chicago
Roger JulianU.Florida
Neil RowlandsCOMDEV
Matt BershadyU. Wisconsin
René DoyonU de Montréal
Jean-Paul Kneib
Marseilles
JWST TFI Gemini F2T2
First light
Spectral resolution
Wavelength range
Field of view
Image quality
P.I.
Prototype single etalon IR tunable filter for JWST. This opto-mechanical design is the basis for F2T2. Contributed by the Canadian Space Agency.
Polished F2T2 optics. F2T2 will be inserted into Flamingos-2 and fed by the Gemini MCAO system.
~2014
100
1.5µm – 3.5µm
~2.5’
Diffraction limited
R. Doyon (Montreal)
Early 2007
800+ (wing suppressed)
30% of the range 1.0µm – 1.35µm
~50”
R. Abraham (Toronto)
MCAO
JWST TFI and Gemini F2T2 share key optics and electronics. The biggest optical difference is that F2T2 is designed to work inside contaminating OH lines, and has two etalons running in series to suppress transmission profile wings.
New observatories will reveal the birth of galaxies
Thirty Meter Telescope James WebbSpace Telescope
The FutureR >> 125 gives more sensitivity but less volume
Maximum R set by intrinsic linewidths
Need larger telescopes to study:• IMF• metallicity• line profiles • clustering
8m30m
Penetrating the IGM with ionized bubbles
Furlanetto & Oh (2005)Furlanetto, Zaldarriaga, & Hernquist (2004)
Penetrating the IGM with ionized bubbles
Best places to find PopIII Ly may be small galaxies inside these ionized bubbles
Luminous sources already enriched(e.g., Davé, Finlator, & Oppenheimer 2005)
HeII (1640): signature of Pop III
Pop III
Pop II
• Only PopIII has detectable HeII (1640) emission
• Schaerer (2003) predicts high (>~ 20 Angstrom) equivalent widths for young, zero-metal bursts
Summary
• Ly at z=8 may be detectable with present-day technology
–high e from WMAP suggests that conditions favorable
–Gemini survey underway with NIRI
• Future will focus on luminosity function, topology of reionization, searches for PopIII