VOSA: A short introduction.

SEDs in the Virtual Observatory

Francisco Jiménez-Esteban

Enrique Solano, Carlos Rodrigo

Astronomy ESFRI & Research Infrastructure Cluster

ASTERICS - 653477

VOSA Intro. F. Jiménez-EstebanGaia Data Workshop, Heidelberg. June 2018 1/11

Why SEDs (Spectral Energy Distributions)?

VOSA Intro. F. Jiménez-EstebanGaia Data Workshop, Heidelberg. June 2018 2/11

Why SEDs (Spectral Energy Distributions)?

VOSA Intro. F. Jiménez-EstebanGaia Data Workshop, Heidelberg. June 2018 3/11

Why SEDs (Spectral Energy Distributions)?

VOSA Intro. F. Jiménez-EstebanGaia Data Workshop, Heidelberg. June 2018 4/11

� Discovery of information: Observational photometry and theoretical models.

Building SEDs: Difficulties

Gaia Data Workshop, Heidelberg. June 2018 VOSA Intro. Enrique Solano 5/11

Building SEDs: Difficulties

� Data Manipulation: From magnitudes to fluxes

VOSA Intro. F. Jiménez-EstebanGaia Data Workshop, Heidelberg. June 2018 6/11

Building SEDs: Difficulties

� Data Manipulation: From theoretical spectra to synthetic photometry

VOSA Intro. F. Jiménez-EstebanGaia Data Workshop, Heidelberg. June 2018 7/11

� Available since 2008.

� > 1500 users.

� > 4.700.000 objects.

� > 100 refereed papers.

http://svo2.cab.inta-csic.es/theory/vosa/

Building SEDs: Difficulties

Gaia Data Workshop, Heidelberg. June 2018 VOSA Intro. Enrique Solano 8/11

Science case

VOSA Intro. F. Jiménez-EstebanGaia Data Workshop, Heidelberg. June 2018 9/11

Science case

� Masses and radii of planets are necessary to:

� Shed light on inflated hot-Jupiters.

� 0.2-2.1MJup. Radii larger than predicted by models.

� Internal heating.

→ Planet radius as a func*on of irradia*on, age,

magnetic fields, winds,…

VOSA Intro. F. Jiménez-EstebanGaia Data Workshop, Heidelberg. June 2018 10/11

Science case

� Empirical determination (model independent) of the radii and

masses of stars hosting planets.

� SED fitting → Fbol and Teff

� L = 4πD²Fbol (D from Gaia-DR2 parallaxes)

� R=sqrt(L/(4πσTeff⁴))

� g= G M / R²

VOSA Intro. F. Jiménez-EstebanGaia Data Workshop, Heidelberg. June 2018 11/11