Looking forward to new telescopes and back to the dark ages Jeremy Mould NOAO

Outline The star formation history of the Universe “First light” NGST ALMA GSMT “First light” after recombination and before reionization Source counts with GSMT

The star formation history Three very complementary views: Ha to redshift 10 with NGST encumbered by dust the FIR calorimeter and CO with ALMA the fossil record with GSMT count the low mass stars and infer the rest encumbered by the IMF

Redshifted emission lines Z [OII] [OIII] Ha Lya .5 5590A 1.0m 1 1.3m 2 1.5m 3 2.0m 4860A 5 2.23m 9 1.2m

SFH in local group galaxies Just count the stars at the base of the red giant branch => SFR(t)

Stellar populations with ELTs Basic assumption: IMF is robust verified by HST studies of local dwarfs maybe inapplicable to Pop.III In all Local Group galaxies, full Star Formation History is on display CMDs show number of stars formed each Gyr in the Hertsprung gap just count the stars as they cross !

First light scenarios We have no real idea what first light was like So, compare with things we do know Globular clusters 10 pc = 1.5 mas Starbursts 100 pc = 15 mas Dwarf galaxies 1 kpc = 0.15 arcsec assuming DA = 0.3 Hubble radius at 3 < z < 10 noting l/d = 10 mas at 1.5m for d = 30m GSMT

First light in the Universe Assembly of galaxies A diffraction limited GSMT will complement ALMA and NGST in resolution First light in the Universe What reionized the Universe ? the first QSOs, formation and growth supernovae in the first globular clusters

SNe in the 1st globular clusters 106 Mo star cluster => 104 SNe in 108 yrs SN 1987A models yield 1051 ergs (only 1048 in photons) 100 such star clusters yield enough energy to ionize 4 x 1010 Mo hydrogen t = 108 yrs in matter dominated Universe is z = 20

Sensitivity GSMT 1m NGST 10m ALMA 1mm Young Globulars 108 Lo J = 31 at z = 3 109 Lo e.g. N5253 Starbursts Dusty ? 1010 Lo 2mJy at z = 3 4mJy at z = 10 Dwarfs SBF P(D)

Source Counts Deeper counts will constrain 1 galaxy/arcsec = 107 gal deg-2 Deeper counts will constrain [cosmology] SFH / evolution assembly

AGN counts Evolution of QSO luminosity and density Sloan survey coming 2dF survey =>

Counts of star forming galaxies Counts of absorbers Clearly a constraint on reionization Counts of star forming galaxies SIRTF will be an interesting preview, but very confusion limited

CIB DIRBE/ IRAS data

IRAS / MIPS galaxy counts

ISO counts

MIPS simulation

White dwarf counts and dark matter Early IMF rich in intermediate mass stars dark halo with 10-3 Mo/pc3 in white dwarfs carbon rich ISM White dwarfs with MJ = 15, J = 30 r -3 density law 104 WDs deg-2 /mag

ALMA/GSMT synergies In galaxy formation science, GSMT offers Resolution Redshifts Inventory of the parts for galaxy assembly which parts ? stars giant HII regions warm ISM