The Transient Radio Sky Astrophysical and Artificial

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Star formation at high redshift (2 lt z lt 7)

• Methods for deriving star formation rates
• UV continuum ionizing photons (dust
  obscuration?)
• Ly a ionizing photons (dust obscuration?)
• Far IR bolometric (covering factor?)
• Radio continuum (synchrotron) empirical (radio
  FIR correlation?)
• Radio free-free/RRLs ionizing photons
  (sensitivity, spectral confusion?)
• All relate mostly to massive stars (gt 5 M_sun) gt
  total SFR depends on extrapolation of IMF, and
  temporal behavior

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Cosmic (proper) time
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Radio-FIR correlation tightest correlation in
extragalactic astronomy
Separating FF Synch is difficult
Thermal dust
M82
Synch.
Free-free
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SKA in context
EVLA
z8
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Cosmic background ½ starlight reprocessed by
dust
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Madau-Lilly plot evolution of cosmic star
formation rate density
Evolution of space density of luminous QSOs (Fan
et al. 2003)
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Galaxy populations at high redshift (2 lt z lt 7)

• Radio galaxies only z gt 0.5 galaxies before 90s
• UV dropouts/Ly-break broadband colors
• Ly a narrow band imaging
• Submm (sub)mm bolometer camera imaging
• QSO Hosts HST, (sub)mm

• QSO absorption lines metalicity evolution,
  parent galaxies
• z0.3 to 2 EROs, faint blue, Butcher-Oemler, mJy
  radio sources, ISO
• GRB hosts
• Pop III stars early reionization by 100 M_sun
  stars in minihalos at z 20?

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High z radio galaxies (L_1.4 gt 1e28 W/Hz)
z0.057 1954
z3.8 1990
10kpc
10kpc
z0.49 1980
z 5.2 2000
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K-z relation HzRGs Giant Ellipticals
zgt8 radio galaxies?
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Alignment effect Jet-induced star
formation? Clumpy morphologies gt forming
ellipticals? 1138-262 z2.2
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Alignement effect Radio-Xray
18kpc
Radio-Lya halo
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Clustering on Mpc scales around HzRGs (1138-262
z2.2) gt protoclusters?
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Dusty radio galaxies at high z? Overdensity of
submm galaxies?
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UV dropouts/Ly break (Ly a)
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(No Transcript)
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Star formation rates in Ly break galaxies
Extinction uncorrected corrected
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Correlation between extinction and SFR gt L_UV
is independent of SFR
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Ly break galaxies highly biased (ie. clustered)
galaxy formation
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Ly break galaxies with Ly a halos
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SUBMM galaxies dust obscured galaxy formation
HDF 850 mm
HDF - optical
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Dust obscured star formation dominates at zgt2?
Submm galaxies L_FIR 1e12 to 1e13 L_sun gt
SFR 100 to 1000 M_sun /yr M_dust 1e8-9 M_sun
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Magic of submm
350 GHz
250 GHz
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Brightest mm source in HDF K 23.5
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Radio photometric redshifts two colors, or
drop-outs
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Redshift distribution
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Next step photometric redshifts
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CO emission gt M(H_2) 1e10-11 M_sun
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Submm galaxies
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QSO host galaxies

• Most low z spheroidal galaxies have SMBH
• M_BH 0.002 M_bulge
• gt Causal connection between SMBH and spheroidal
  galaxy formationn (Gebhardt et al. 2002)?

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z6.4 S_2505.5mJy
23221944

• 30 of luminous QSOs have S_250 gt 2 mJy
• L_FIR gt 7e12 M_sun
• Dust heating starburst or AGN?

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Radio-to-IR SED M82
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CO(1-0) w. VLA L_FIR 3e13 L_sun M(H_2) 1e11
M_sun
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A Molecular Einstein Ring VLA 45 GHz
observations of CO2-1 emission from the
gravitationally lensed QSO 23221944 at z4.12
(Carilli et al. 2003)
Keck Rband
VLA CO2-1
2
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Using the gravitational lens to probe sub-kpc
scales in 23221944 A starburst disk
surrounding a SMBH gt coeval SMBH galaxy
formation?
Optical QSO
Starburst disk molecular gas, dust, radio
continuum
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• Starbursts in QSO host galaxies?
• 30 of luminous QSOs (M_B lt -27) have L_FIR
  1e13 L_sun (independent of redshift)
• Z 2 sample All L_FIR luminous QSOs detected at
  1.4 GHz, and in all cases q consistent with
  star forming galaxy (2.3 /- 0.3)

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• Questions
• Relationships between different high z galaxy
  types?
• Halos masses and end-products (spirals,
  ellipticals)?
• Is gt 1000 M_sun/yr possible, sustainable (Heckman
  limit)?
• IMF top heavy? Star formation in extreme
  environments (P100xISM)? Timescales?
• Dust formation at zgt6 gt1e8 M_sun in lt 0.7 Gyr?
• What fraction of high z galaxy formation is
  dust-obscured?
• Submm galaxies redshift distribution?
• radio FIR correlation mechanism? vs. redshift?
• M-s relation coeval SMBH and galaxy formation?
• QSO dust heating star formation or AGN?
• L_FIR from S_250?
• X gas mass to CO luminosity conversion? L_FIR
  to dust mass conversion?
• Pop III stars, minihalos, and first luminous
  objects role of radio astronomy?