Abstract
A sunspot catalogue was published by the Coimbra Astronomical Observatory (Portugal), which is now called the Geophysical and Astronomical Observatory of the University of Coimbra, for the period 1929 – 1941. We digitalised data included in that catalogue and provide a machine-readable version. We show the reconstructions for the (total and hemispheric) sunspot number index and sunspot area according to this catalogue and compare it with the sunspot number index (version 2) and the Balmaceda sunspot area series (Balmaceda et al. in J. Geophys. Res. 114, A07104, 2009). Moreover, we also compared the Coimbra catalogue with records made at the Royal Greenwich Observatory. The results demonstrate that the historical catalogue compiled by the Coimbra Astronomical Observatory contains reliable sunspot data and can therefore be considered for studies about solar activity.
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Acknowledgements
This work was partly funded by FEDER-Junta de Extremadura (Research Group Grant GR15137 and project IB16127) and from the Ministerio de Economía y Competitividad of the Spanish Government (AYA2014-57556-P and CGL2017-87917-P). JF, TB, and AL acknowledge support from the Fundação para a Ciência e a Tecnologia and Centro de investigação da Terra e do Espaço da Universidade de Coimbra Funds (UID/Multi/00611/2013) and ReNATURE (CENTRO-01-0145-FEDER-000007). Authors have benefited from the participation in workshops at the International Space Science Institute.
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Appendix
Bibliographic references containing the original data of the Coimbra Astronomical Observatory are listed in this appendix:
da Costa Lobo, F.M.: 1929, Anais do Observatório Astronómico da Universidade de Coimbra Tomo I, Universidade de Coimbra, Coimbra.
da Costa Lobo, F.M.: 1933, Anais do Observatório Astronómico da Universidade de Coimbra Tomo II, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1936, Anais do Observatório Astronómico da Universidade de Coimbra Tomo III 1931, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1937, Anais do Observatório Astronómico da Universidade de Coimbra Tomo IV 1932, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1940, Anais do Observatório Astronómico da Universidade de Coimbra Tomo V 1933, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1941, Anais do Observatório Astronómico da Universidade de Coimbra Tomo VI 1934, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1942, Anais do Observatório Astronómico da Universidade de Coimbra Tomo VII 1935, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1943, Anais do Observatório Astronómico da Universidade de Coimbra Tomo VIII 1936, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1945, Anais do Observatório Astronómico da Universidade de Coimbra Tomo IX 1937, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1947, Anais do Observatório Astronómico da Universidade de Coimbra Tomo X 1938, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1949, Anais do Observatório Astronómico da Universidade de Coimbra Tomo XI 1939, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1957, Anais do Observatório Astronómico da Universidade de Coimbra Tomo XII 1940, Universidade de Coimbra, Coimbra.
dos Reis, M.: 1965, Anais do Observatório Astronómico da Universidade de Coimbra Tomo XI 1941, Universidade de Coimbra, Coimbra.
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Carrasco, V.M.S., Vaquero, J.M., Gallego, M.C. et al. Sunspot Catalogue of the Observatory of the University of Coimbra (1929 – 1941). Sol Phys 293, 153 (2018). https://doi.org/10.1007/s11207-018-1373-7
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DOI: https://doi.org/10.1007/s11207-018-1373-7