Transformation equations between GALEX and UBV photometric systems


Creative Commons License

Alan N., Bilir S., Güçtekin S. T., Çelebi M., Yontan T., Plevne O., ...More

Turkish Physical Society 35th International Physics Congress, TPS 2019, Konacik-Bodrum, Turkey, 4 - 08 September 2019, vol.2178 identifier identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 2178
  • Doi Number: 10.1063/1.5135420
  • City: Konacik-Bodrum
  • Country: Turkey
  • Keywords: star: main-sequence, technical: photometric, catalogue, sky survey. Inadequacy of photometric data in the U-filter of RIK type stars in the solar neighborhood
  • Istanbul University Affiliated: Yes

Abstract

The insufficiency of photometric data in the U-band of the RIK-type stars in the solar neighborhood makes difficult to determine the flux of the blue region of their spectral energy distributions, and causes to the inadequacy in the estimation of the photometric metallicit,' and the color excesses of these stars. To overcome this problem, the U- f' color indices of 556 stars in different luminosity class, whose spectroscopic, photometric and astrometric data are well known, were calculated using derived transformation equations sensitive to GALEX and B V color indices. In order to obtain the transformation equations; GALEX DR7.ATUF and Johnson-Morgan UBV photometric data were used. Model atmosphere parameters (Te; log g, [FeIH1) collected from the literature concerning the stars were separated into different metal abundance intervals and FIR diagrams were created. Then PARSEC mass tracks were added to these HR diagrams to determine the luminosity classes of the stars in the sample. The transformation equations, which were designed based on two color indices; were derived for stars in different luminosity classes. The analyses showed that LI- T7 color index calculations performed by the newly obtained photometric transformation equations, provide highly sensitive results (A(U-1,)o 0.05 mag).