author = "Carlesso, Franciele",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)}",
                title = "Study of cavities geometry for absolute radiometer",
            booktitle = "Anais...",
                 year = "2018",
         organization = "IAU General Assembly, 30.",
             abstract = "The measurement of the Total Solar Irradiance (TSI) and its 
                         variations are very important to understand the influence of Suns 
                         radiant output on the Earths climate. Space-borne instruments have 
                         made TSI measurements continually and allowed advances in the TSI 
                         understanding. These measurements rely on active cavity 
                         radiometers, which use black interior surfaces to absorb incident 
                         sunlight. Black Ni-P was firstly applied in active cavity 
                         radiometers for measuring solar irradiance in TIM (Total 
                         Irradiance Monitor) instrument [1]. The development of an absolute 
                         radiometer is currently been done at INPE. We obtained black Ni-P 
                         by electroless deposition for application in the interior of the 
                         silver cavities. We used bidirectional reflectance distribution 
                         function (BRDF) data to describe the surface reflectance 
                         properties of the Ni-P film. The BRDF data were used in the 
                         geometry study of the absorber cavity in a ray tracing software - 
                         ZEMAX. These measures allowed cavities geometries optimization 
                         considering the characteristics of the black Ni-P produced at 
                         INPE. We intend to use this cavity in a bench prototype radiometer 
                         under development. The current status of the study and obtained 
                         results are presented in detail.[1] G. Kopp, Journal of Space 
                         Weather and Space Climate, 4, A14 (2014).",
  conference-location = "Vienna, Austria",
      conference-year = "20-31 aug.",
             language = "pt",
        urlaccessdate = "26 nov. 2020"