| Full text | |
| Author(s): |
Selhorst, Caius L.
[1]
;
Kallunki, Juha
[2]
;
Gimenez de Castro, C. Guillermo
[3, 4]
;
Valio, Adriana
[3]
;
Costa, Joaquim E. R.
[5]
Total Authors: 5
|
| Affiliation: | [1] Univ Cidade Sao Paulo, Univ Cruzeiro Sul, NAT Nucleo Astrofis, Sao Paulo, SP - Brazil
[2] Aalto Univ, Metsahovi Radio Observ, Kylmala - Finland
[3] Univ Presbiteriana Mackenzie, CRAAM, BR-01302907 Sao Paulo, SP - Brazil
[4] Univers Buenos Aires, IAFE, CONICET, Buenos Aires, DF - Argentina
[5] Inst Nacl Pesquisas Espaciais, CEA, BR-12201970 Sao Jose Dos Campos, SP - Brazil
Total Affiliations: 5
|
| Document type: | Journal article |
| Source: | SOLAR PHYSICS; v. 294, n. 12 DEC 16 2019. |
| Web of Science Citations: | 0 |
| Abstract | |
To better understand the influence of the activity cycle on the solar atmosphere, we report the time variation of the radius observed at 37 GHz (lambda=8.1 mm) obtained by the Metsahovi Radio Observatory (MRO) through Solar Cycles 22 to 24 (1989 - 2015). Almost 5800 maps were analyzed, however, due to instrumental setup changes the dataset showed four distinct behaviors, which required a normalization process to allow for the whole interval analysis. When the whole period was considered, the results showed a positive correlation index of 0.17 between the monthly means of the solar radius at 37 GHz and solar flux obtained at 10.7 cm (F10.7). This correlation index increased to 0.44, when only the data obtained during the last period without instrumental changes were considered (1999 - 2015). The solar radius correlation with the solar cycle agrees with the previous results obtained at mm/cm wavelengths (17 and 48 GHz), nevertheless, this result is the opposite of that reported at submillimeter wavelengths (212 and 405 GHz). (AU) | |
| FAPESP's process: | 19/03301-8 - Observation and models of solar and stellar active regions at radio wavelengths (mm/sub-mm) |
| Grantee: | Caius Lucius Selhorst |
| Support Opportunities: | Regular Research Grants |