Science Background to Galaxies Case Piero Rosati, ESO

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Science Background to Galaxies Case(Piero
Rosati, ESO)

• Characterizing properties and evolutionary
  history of galaxies by comparing multi-color
  photometry with a spectral library of models (or
  observed templates)
• Methodology adopted in the Demo is shared by a
  broad range of astrophysical applications
• Elements and Applications used in the workflow
  routinely applied by astronomers for the
  interpretation of their data
• VO and Grid concepts Registry used to discover
  Data and Applications, distributed resources,
  images/spectra studied with VO-compliant
  visualization tools

AVO Jan 2005 Demo Background to the Galaxies
Case (ESAC Jan 25, 2005)
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Methodology Flow
Multi-band Photometric Catalog
Spectral synthesis models or Library of observed
templates
More Applications..
Match/Fit
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Comparing SEDs with models the case of Lyman
Break Galaxies (drop-outs)
(Dickinson 2000)
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Comparing SEDs with templates constraining
nature of LBGs at z 3
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Comparing SEDs with models constraining ages,
stellar masses and metallicities
(Cimatti et al. 2001)
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Comparing SEDs with models/templates
constraining redshift
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Watch the Demo now !
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• Spectral Synthesis Models
• compute spectral evolution of stellar
  populations for a wide range of star formation
  histories and stellar population parameters
• GALAXEV (Bruzual Charlot, 2004)
• PEGASE (Fioc Rocca-Volmerange, 2003)
• Interface to input parameters and output files
  not user friendly
• format of output files and metadata not
  homegeneous ? they benefit from a web-service
  VO compliant interface

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ELAIS Catalog (Rowan-Robinson et al.
2004) (http//astro.ic.ac.uk/Elais/index.html)

• European Large-Area ISO Survey 3523 ISO selected
  sources over 10 deg2 (5 fields)
• Broad wavelength coverage ISO 6.7, 15, 90,
  175 µm VLA 20cm 2MASS J, H, K WFS _at_INT U,
  g, r, I, ZFinal band-merged catalog published
  in Rowan-Robinson et al.
• Large fraction of sources have spectroscopic
  redshifts
• Public Spitzer Observations from the SWIRE survey
  (see Demo cutouts)

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Further Applications of Spectral Models

• Evolutionary tracks in color-color space
• Color terms computation in multi-band photometry
• K-corrections computation
• Passive evolution of Luminosities, Colors
• Simulations of galaxy evolution, etc.