Abstract
The results here discussed were produced by a program of visual observations carried out at the Calern Observatory from 1975 to 1998. The sun radius data collected display some variability, in particular an oscillation of 0.2′' amplitude and 11.8 years period which seems anticorrelated with the sunspot cycle. These apparent variations might also be put together with other structural solar parameters: frequency shifts of low-degree p-modes or neutrino flux. Moreover, the series shows a deviation from the mean diameter as a function of heliographic latitude. The origin of these apparent variations is currently unclear and will be better understood by ground measurements over a long period of time (e.g. the DORAYSOL Instrument and Program at Calern) and by the results expected from the future PICARD mission of the French Space Agency CNES.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Comptes Rendus de l'Academie des Sciences Series IIB Mechanics Physics Astronomy
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
