PGos3: the prototype version of the Legacy ToolPGos3: the prototype version of the Legacy Tool

Roberto Terlevich

INAOE, Puebla, Mexico andIoA, Cambridge, UK

La Thuile, March 8th 2005

Elena Terlevich INAOE, Mexico Coordination

Miguel Cerviño IAA, Spain Coordination

Peter Anders Gottingen University, Germany SSP & galaxy modeling

Emanuele Bertone INAOE, Mexico Atmosphere Models

Sandro Bressan Observatorio di Padova, Italy SSP & galaxy modelling

Uta Fritze-v.Alvensleben Gottingen University, Germany SSP & galaxy modeling

Jesús González INAOE, Mexico Observational Databases, Data Mining

Valentina Luridiana IAA, Spain Conceptual design, Documentation, Photoionization modelling

Ángeles López INAOE, Mexico System support

Aurelio López INAOE, Mexico Conceptual design

Miguel Martínez INAOE, Mexico System support

Christophe Morisset UNAM, Mexico System development, VOTable management, Photoionization models

Enrique Pérez IAA, Spain Conceptual design

Carlos Rodrigo LAEFF, Spain System development, PGos3 design and database management, VOTable management

Roberto Terlevich INAOE, Mexico Conceptual design, Observational Databases

The need for a theory-data intelligent interface

● Many of the most fundamental problems in star cluster formation and evolution seem to be on the verge of solution by combining multi-wavelength observations with theoretical modelling that integrates stellar evolution, stellar dynamics, gas dynamics and chemical evolution, as well as the microphysics implicit in photo ionisation, radiative transfer, diffusion, dust formation and mixing, to name a few.

● Most groups so far have concentrated in either producing large quantities of data or model computing. The limitation in the approach means that only a small part of the phase space volume has been explored looking for solutions when comparing theory and observations.

● Substantial progress rests with methods that can deal simultaneously with large observational and theoretical datasets, i.e. megadatasets.

● Progress will therefore depends on improving not only the theory and observations but the interface between them. This is the area that we are actively exploring.

● As a first stage we are developing multiwavelenght Evolutionary Synthesis capability for megadatasets (3D spectroscopy).

Evolutionary Synthesis

● Is a powerful tool to interpret the light of a stellar population (introduced by Tinsley 1968)

● Makes estimates of the history of star formation, chemical evolution and IMF

● During the last decade models have improved significantly using the latest evolutionary tracks and stellar libraries (Cervino & Mas-Hesse 1994;Fioc & Rocca-Volmerange 1997;Leitherer et al. 1999;Vazdekis 1999;Buzzoni 2002;Sculz et al. 2002;Bruzual & Charlot 2003)

● However it is well known that the power of this method is extremely dependent on the reliability of the stellar models used as ingredients (Leitherer, Fritze-v.Alvensleben & Huchra 1996).

About the Legacy Tool

● We are building a sophisticated open-source software tool (the ``Legacy Tool'' ) that incorporates the most advanced theoretical high-resolution synthesis models of stellar populations, chemical evolution, abundance determination and chemo-dynamical models. The authors of the codes belong to this collaboration.

● This tool brings many dispersed efforts into a single access mode that will guide the user via a user-friendly interface.

● Includes modules of Data Mining and Machine learning algorithms to obtain from large databases the maximum of information in a fast and accurate manner.

● An interface is also planned, with chemical evolution, photoionization, chemodynamical and dynamical models. In addition, the LT will include a series of utilities for the analysis of both theoretical and observational data, e.g. the determination of colours from `filters', extinction correctors, etc.

PGos3 present status

● The main problem to solve when bringing to a common environment software that has been independently developed is that of communication and interoperability

● Moreover, the results from the models should have a format that allows easy comparison with the data.

● The solution: VOtables

● A working prototype of the Legacy Tool, the PG0s3 is being implemented in the IBM super-server of the INAOE Virtual Observatory http://ov.inaoep.mx/

● Already allows the comparison of the different ingredients and synthesis code results. Big surprises!!

PGos3 Present Status

NUV-Optical High Resolution @ 3Myr

NUV-Optical High Resolution @ 3Myr

Determination of Stellar Population

Parameters in Galaxies Using Active

Instance-based Machine Learning

(Solorio et al 2005)

Very Fast!

S/N=5

Residuals and Lick indeces

PGos3 Second Stage

PGos3 Third Stage

THE BEGGINING

AIMS

● Our group aims to provide the infrastructure to assemble interdisciplinary teams with the breath of expertise in computation, astrophysics, statistics, dynamics and visualization to exploit the anticipated massive data flow from future cosmology-related experiments, both ground and space based.