Polarbase SSAP ivo://ov-gso/ssap/polarbase OV-GSO Polarbase SSAP service for ESPaDOns/Narval spectra Pascal Petit Spectropolarimetry Spectroscopy This database contains reduced spectra from Narval and ESPaDOns instruments http://polarbase.irap.omp.eu https://www.polarbase.ovgso.fr/download/ssa_polarbase? query custom archival 180 0 0