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Multi-wavelength Astronomy using VOSpec Deborah Baines European Space Astronomy Centre (ESAC) Science Archives and VO Team. Outline. The VOSpec tool and it’s functionalities Access to services: Simple Spectral, Simple Line and Theoretical Services VOSpec Demo VOSpec in the literature
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Multi-wavelength Astronomy using VOSpec Deborah Baines European Space Astronomy Centre (ESAC) Science Archives and VO Team
Outline • The VOSpec tool and it’s functionalities • Access to services: Simple Spectral, Simple Line and Theoretical Services • VOSpec Demo • VOSpec in the literature • Summary
ISO PHT HST FOS IUE ISO LWS HST INES HUT EUVE VOSpec • Multi-wavelength spectral analysis tool developed at ESAC by ESA-VO • Create a SED with spectra from: • a wide range of different providers registered in the VO Registry • local data (FITS, ASCII, VOT) • User-friendly (true!) SSAP Wrapper applied on your own set of local spectra. • Graphical options: • plot colour, title and axis label modifications • Zoom/unzoom • Automatic conversion of all units via dimensional analysis.
Arithmetic between spectra VOSpec: spectral analysis functionalities • Line fitting (Gaussian, Lorentzian, Voigt). • Rest-frame (redshift correction) • Spectral arithmetic and convolution between spectra. • De-reddening • Calzetti law • Cardelli-O’Donnell law • LMC Fit of an absorption line profile with different models (Gaussian, Lorentzian, Voigt)
Filtering Line Mirroring Spectrum Mirroring Polynomial fitting Bisector applied to a spectrum in velocity space VOSpec: spectral analysis functionalities cont. • Continuum fitting (BB, polynomial). • Integrated flux, line flux and equivalent width calculations. • Filtering • Averaging • Convolution • Wavelet • Tuning: rebinning, reject zero points, cut spectrum. • Mirroring: line and spectrum mirroring. • Bisector • Wavelength-to-velocity conversion.
Simple Spectral Access (SSA) services • SSA services accessed by VOSpec • SSA services registered in the VO registry. • Over 30 services. • 10 within the past year which include: • Hubble Legacy Archive (HLC) (near-UV to near-IR) • AXIS-XMS (An XMM International Survey – X-ray Medium Survey). 319 X-ray sources observed in optical. • EPIC Spectra for the 2XMMi Catalogue. 96176 EPIC spectra. • HEROS spectrograph, 6000 high resolution (R=20000) spectra, in optical.
Simple Line Access through VOSpec • VOSpec provides access to atomic and molecular line Databases (SLAP): • NIST Atomic Spectra • CHIANTI (X-rays) • CIELO (XMM-Newton) • IASD (ISO) • LERMA (molecular) • STSCI (UV) • This allows on-the-fly identification of transitions associated to a given observed feature.
Access to Theoretical models (TSAP) • 10 Theoretical Spectral Services accessed by VOSpec which include: • Evolutionary synthesis models • Models of stellar atmospheres, e.g. Kurucz, PGos3 • D’Alessio models of pre-main sequence stellar discs. • The VOSpec Normalization tool can be applied to both theoretical and non-calibrated spectra. Kurucz stellar model and D’Alessio model of PMS discs fit to UV and IR spectra of HD 141569
The power of interoperability Aladin: multipanel imaging AstroScope: catalogue search (PLASTIC) GB 2MASS SDSS ROSAT Chandra VOSpec: generation of SEDs TOPCAT: tabular data plotting/manipulation
Demo – A typical session: http://www.sciops.esa.int/SD/ESAVO/images/VOSpec/VOSpec_ABAur_flash.htm
VOSpec in the literature • Scientific cases/papers (not complete): • Guainazzi M. et al (2008) ‘Catalogue of ionized emission line spectra in obscured AGN’, AdSpR, 41, 1998. • Guainazzi et al (2007) ‘A VO-based solution to the origin of soft X-ray emission in obscured AGN’, HiA, 14, 582, Proceedings of the IAU, 2006. • Richards, et al (2005) ‘Hunting post-AGB/RSG objects using Virtual Observatories and other internet-based technology’, MmSAI, 76, 467. • Technical papers: • Laruelo A. et al (2008) ‘VOSpec Spectral Analysis Tools’, ASPC, 394, 513. • Salgado J. et al (2007) ‘How to Access Spectral Line Databases in the IVOA: SLAP Services in VOSpec’, ASPC, 376, 603. • Osuna P. et al (2006), ‘Theoretical Support to Observational data in VO Context’, ASPC, 351, 363.
VOSpec Summary • On-the-fly SED generation with VOSpec • Spectra access from SSAP-compatible server • Automatic handling of units • Spectral analysis tools • Large number of spectral analysis tools available • Multi-component fit possible • Interoperability • VOSpec uses PLASTIC • Literature - VOSpec beginning to be used by the scientific community • Usage on large sets of data - Mainly designed to handle one source at the time → highly interactive. - Good News: ability to handle large lists of objects about to be developed.
To know more • VOSpec web pages: http://esavo.esac.esa.int -> http://www.sciops.esa.int/index.php?project=ESAVO&page=vospec • To launch VOSpec: http://esavo.esac.esa.int /vospec/