@Article{ConstāncioJśniorAdAgArMaOkWi:2020:SiEmFu,
               author = "Const{\^a}ncio J{\'u}nior, M{\'a}rcio and Adhikari, Rana X. and 
                         Aguiar, Odylio Denys de and Arai, Koji and Markowitz, Aaron and 
                         Okada, Marcos Andr{\'e} and Wipf, Chris C.",
          affiliation = "{Instituto Nacional de Pesquisas Espaciais (INPE)} and {California 
                         Institute of Technology} and {Instituto Nacional de Pesquisas 
                         Espaciais (INPE)} and {California Institute of Technology} and 
                         {California Institute of Technology} and {Instituto Nacional de 
                         Pesquisas Espaciais (INPE)} and {California Institute of 
                         Technology}",
                title = "Silicon emissivity as a function of temperature",
              journal = "International Journal of Heat and Mass Transfer",
                 year = "2020",
               volume = "157",
                pages = "e119863",
                month = "Aug.",
             keywords = "LIGO, Silicon, Thermal emissivity, Gravitational waves.",
             abstract = "In this paper we present the temperature-dependent emissivity of a 
                         silicon sample, estimated from its cool-down curve in a constant 
                         low temperature environment ( ~ 82K). The emissivity value follow 
                         a linear dependency in the 120260 K temperature range. This result 
                         is of great interest to the LIGO Voyager gravitational wave 
                         interferometer project since it would mean that no extra high 
                         thermal emissivity coating on the test masses would be required in 
                         order to cool them down to 123 K. The results presented here 
                         indicate that bulk silicon itself can have sufficient thermal 
                         emissivity in order to cool the 200 kg LIGO Voyager test masses 
                         only by radiation in a reasonable short amount of time (less than 
                         a week). However, it is still not clear if the natural emissivity 
                         of silicon will be sufficient to maintain the LIGO Voyager test 
                         masses at the desired temperature (123 K) while removing power 
                         absorbed by the test masses. With the present results, a black 
                         coating on the barrel surface of the test masses would be 
                         necessary if power in excess of 6 W is delivered. However, the 
                         agreement we found between the hemispherical emissivity obtained 
                         by a theory of semi-transparent Silicon and the obtained 
                         experimental results makes us believe that the LIGO Voyager test 
                         masses, because of their dimensions, will have effective 
                         emissivities around 0.7, which would be enough to remove about 8.6 
                         W (7.5 W) for a shield at 60 K (80 K). This hypothesis may be 
                         confirmed in the near future with new measurements.",
                  doi = "10.1016/j.ijheatmasstransfer.2020.119863",
                  url = "http://dx.doi.org/10.1016/j.ijheatmasstransfer.2020.119863",
                 issn = "0017-9310",
             language = "en",
           targetfile = "constancio_silicon.pdf",
        urlaccessdate = "26 abr. 2024"
}