Physics
Scientific paper
Dec 2010
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010nspm.conf...58d&link_type=abstract
Proceedings of the 20th National Solar Physics Meeting, held 31 May - 4 June, 2010 in Papradno, Slovakia, p. 58-63
Physics
Scientific paper
The solar activity (SA) evolution levels are not identical in the northern and southern Sun's hemispheres. This fact was repeatedly confirmed in the past by the analysis of a number of long-term observations of various SA indices in individual atmospheric layers of the Sun and in different bandwidths. The north-south asymmetry (NSA) is thus a significant tool in investigation of long-term SA variations. This paper presents a software tool to determine the NSA of the area of bright chromospheric plages, as measured in the Ca II K3 spectroheliograms registered since 1926 in the Observatário Astronómico da Universidade de Coimbra, Portugal, as well as evolution of sizes of these areas in the period 1996 - 2006. The algorithm of the program is limited to determining the total area of bright features in the Ca II K3 emission line based on the definition of the threshold value for relative brightness and, therefore, it does not resolve brightness of individual chromospheric features. A comparison and cross-correlation of this NSA with the NSAs found for the sunspots and coronal green line brightness have been added. In the near future we intend to 1) determine the NSA of the area of bright chromospheric Ca II K3 regions back to the year 1926, and 2) compare the evolution of the surface area of these regions in the period 1970-2006 with the evolution of the magnetic index obtained at Mt. Wilson Observatory, which would also help in setting up a proxy reconstruction of the magnetic index back to 1926. Since 2007 new spectroheliograms have been recorded using a CCD camera and, therefore, in the future we will also address this issue for the period 2007 - present.
Dorotovič Ivan
Garcia Arnaldo
Journoud P.
Rybák Ján
No associations
LandOfFree
North-south asymmetry of Ca II K regions determined from OAUC spectroheliograms: 1996 - 2006 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with North-south asymmetry of Ca II K regions determined from OAUC spectroheliograms: 1996 - 2006, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and North-south asymmetry of Ca II K regions determined from OAUC spectroheliograms: 1996 - 2006 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1309697