Transcript Web based Spectrum Databases and Utilities

Web based
spectrum databases
and utilities
László Dobos
Tamás Budavári
István Csabai
MAGPOP kick-off meeting, January 2005. Cassis
Main goal
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Develop easy-to-use software for further
scientific application (photo-z)
Uniformed web interface
 Web Services
 Virtual Observatory compliant

Advantages of web based tools
Databases are 100s of Gbytes
 Database and tools are on the same high
performance server
 Only results pushed through the network
 No local installation
 No local storage required
 No high network traffic
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Tasks to do
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Convert legacy datasets into hierarchical
databases
Create wrappers for existing software tools to
provide web service interface
Create easy-to-use web sites to test tools and
access all documentation you need
Write web service client programs in minutes to
access data and use the tools
Spectrum Database
Developed at JHU for the SDSS spectra
 More than 1,000,000 spectra, 150Gb
 SDSS, 2dF
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Users can upload their own spectra and
store in the database
Spectrum search
Cone search by celestial coordinates
 Advanced search:
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 Object
class
 Redshift
 Wavelength coverage
 Etc.
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SQL search for complex queries
Search results
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Plot them on a graph
Perform on-the-fly operations:
 Put
into restframe
 Normalize flux
 Generate composite spectra
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Save them to ‘my spectra’
Download them in several formats
 ASCII,
XML, VOTable
‘My spectra’
Password protected part of the database
 You can save results of computations here
 Run queries on them, such on the large
database
 Publish them to other users
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Filter profile service
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Central repository of optical filter profile curves
Advanced search possibilities
Users can upload their own filter profiles
Can be user with the spectrum database to
calculate synthetic magnitudes (still in
development)
Bruzual & Charlot Models
Wrapper interface for the Fortran program
 Provides similar web interface as the
Spectrum Service
 Run modelling with few mouse clicks
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Not all program features are available via
the interface
BC Modelling Results
Display the result on a graph
 Download in several formats

 XML
 VOTable
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Upload to a remote database,
to ‘my spectra’
Color-space visualization tool
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Plot 2D and 3D histograms of the
distribution of galaxies in the color space
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Plot the color-index curve of spectra by
redshift
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Still in development
Web addresses
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Spectrum service:
http://voservices.net/spectrum
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Filter profile service:
http://voservices.net/filter
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Bruzual-Charlot Galaxev 2003
http://redshift.elte.hu/bc03ws