The ASTROF Far Infrared AllSky Survey

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The ASTRO-F Far Infrared All-Sky Survey
Seb Oliver, Rich Savage, Bob Nichol
the ASTRO-F team

• ASTRO-F
• Why all-sky FIR survey?
• AAOmega Follow-up?
• Science from AAO/ASTRO-F z-surveys

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The ASTRO-F collaboration.

• Hiroshi Shibai, Toshio Matsumoto, Hiroshi
  Murakami, Takao Nakagawa, Mitsunobu Kawada,
  Takashi Onaka, Hideo Matsuhara, Tsuneo Kii, Issei
  Yamamura, Chris Pearson, Takehiko Wada, Michael
  Rowan-Robinson, Glenn White, Seb Oliver, Rich
  Savage, Steve Serjeant, Toshinobu Takagi and the
  ASTRO-F team
• A collaboration between Japan, Korea, ESA and
  the IKSG (Imperial-Kent-Sussex-Groningen)
  consortium

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ASTRO-F Satellite Instruments

• Mid-Far IR satellite
• 2 instruments (FIS, IRC)
• Surveyor observatory
• Launch date August 2005
• Mission lifetime 550 days

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The all-sky survey

• 4 bands, paired up to observe at 80 and 160
  microns.
  
• The first ever all-sky survey at 160 microns.
• Will see of order 106 sources.
• Objects out to redshift of well beyond unity.
• Cover 95 of sky, 99 reliability.

Mission IRAS ISO (ELAIS) SPITZER (SWIRE)
Wavelength 60µm 90µm 70µm
Sensitivity 500 mJy 100 mJy 20 mJy
Area All Sky 12 sq.deg. 50 sq.deg.
Numbers 104 103 104
ASTRO-F 80µm 30 mJy 1000 sq.
deg 105
ASTRO-F 80µm 200 mJy
all-sky 2-3X105
Preliminary numbers
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Why Far Infrared?

• Detecting hidden star-formation
• Quantifying star-formation
• Insensitive to Galactic extinction
• Strong emission lines and easy redshift follow-up

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Because its there
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Obscured star-formation
Hopkins et al. 2001 ApJ 122, 288
Lots of action at z1
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FIR as a measure of star-formation
Hopkins et al. 2003 ApJ 599, 971
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Why all-sky?

• Rare objects
• Good statistical sampling of populations
• Access to large spatial scales
• Overcome cosmic variance
• Clean window function

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Practical Considerations for AAOmega
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Expected numbers of sources
3?105sr-1 100 sq.deg.-1 300 AAO-1
30 mJy
Spitzer number counts from Dole et al. 2004
astro-ph/0406021
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Expected redshift distribution
Pearson et al.2004MNRAS.347.1113P
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Expected optical magnitudes
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Emission line equivalent widths
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Going beyond z1?

• UV spectra of IRAS galaxies?
• Wu et al. 2002
• http//morpheus.phys.lsu.edu/starbrst/

AAW_at_z1.5
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Depth vs Area Preliminary
H. Matsuhara
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Science from a mega redshift survey
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Science

• Cosmological star-formation
• star-formation in normal galaxies
• monsters the transition from IRAS to SCUBA
• star-formation environment on small-large
  scales
  
• Galaxies as probes of cosmology
• Integrated Sachs Wolfe (ISW) effect
• Baryon Oscillations

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Star-formation in monsters
Luminosity functions
SCUBA
Dz 0.2 DLogL 0.2 DN 100
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Star-formation Environment

• Smallest scales (internal to galaxies)
• LFIR vs LOPT SFR vs Stellar mass
• requires large dynamic range in L and z
• Small scales
• SF as a function of local density
• requires large variety of environments
• I.e. sufficient volume to include many clusters
  at different z 1000 sq deg.
  
• Largest scales
• SFR density field
• Requires large volume

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Resolving the SFH in Time and Space
Kauffmann et al. (1999) 21x21x8 (Mpc/h)3 red ? b
lue increasing SFR
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Environments SFR
Balogh et al. astro-ph/0311379
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Large-scale Structure
Gonzalez-Solares E. A., Oliver S. et al. 2004
MNRAS
but stronger clustering in deep ISO surveys
SCUBA surveys
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ASTRO-F LSS c.f. other IR surveys
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Late-time Integrated Sachs Wolfe
(ISW) Effect
The ISW measures a differential redshift of CDM
photons in a evolving potential well (see
figure). In a flat, matter-dominated universe,
density fluctuations dont grow. Therefore if
the Universe is flat, any detected ISW effect is
a direct physical measurement of Dark Energy
Figure from Wayne Hu
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ISW and the SDSS

• Searching for a detection
• LRG selection to z0.6 (Eisenstein et al. 2001)
• 3500 sq degrees
• Achromatic (no contamination)
• Jacknife errors
• Compared to a null result
• 90 all samples
• Low redshift sample contaminated by stars
• Individually 2s per redshift slice
• 4 redshift shells (significant overlap)

Grey Clean, Red Q, Blue W, Green V
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Future ISW Directions

• dg/dz is a very powerful probe
• See Cooray, Huterer, Baumann 2003
• Errors dominated by 2 effects
• Cosmic Variance. Therefore all-sky surveys are
  key
  
• ASTRO-F all-sky out to z1.5
• 3sigma detection on large scales (2 degrees) in
  3 z shells (figure opposite)
  
• Accurate photometric redshifts are also key
• Need enough (real) redshifts to determine n(z)
  precisely (eg SDSS-2dF LRG survey)
  
• Make thinner z shells

z0.3
z0.5
z1.0
The S/N for the 3 bands is 3.0, 3.4 and 4.1 for
N60, WideS and WideL
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Prediction Explanation

• Assumes Lambda CDM
• Used gaussian n(z) for the three slices
• N60 z_mean0.3 z_sig0.1
• WideS z_mean0.5 z_sig0.2
• WideL z_mean1.0 z_sig0.5
• Assume all-sky (no galaxy subtract)
• The S/N for the 3 bands is 3.0, 3.4 and 4.1 for
  N60, WideS and WideL
  
• Uses Halo model

• .

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Baryon Oscillations

• A clean measurement of Dark Energy parameters
• Tentative detections
• PSC-z 20k sources, all-sky 1s (? Et al.)
• 2dFGRS 200k sources, 1000 sq deg. (Percival et al. 2003)
  
• 10 s measurement requires
• 1 Million redshifts
• 10k sq deg.
• AAO omega
• 3000 Pointings 10k sq deg 1M galaxies
• _at_ 1hr per pointing 400 nights

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Baryon Oscillations

• Measuring the baryonic oscillations gives you a
  standard ruler at known redshift, which gives..
  

• 300 nights using FMOS on Subaru (1000 sq. deg.)
  (predictions by Karl Glazebrook)or cover the
  whole southern sky using ASTRO-F and AAOmega in
  375 nights!

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Conclusion

• ASTRO-F
• Launch date August 2005 (1 year away)
• Major new all-sky survey Super IRAS
• Will probe star-formation 0
• Probing galaxy clustering in general on all
  scales
  
• Redshift surveys with AAOmega Super PSC-z
• 1,000 sq. deg. 40 nights - SFR(r,t) ISW
• 10,000 sq. deg. 400 nights - Baryon
  Oscillations (ASTRO-F )