On anticorrelation of number Coronal Bright Points with sunspot number during 1996-2005
Abstract
X-ray Bright Points XBP were extensively studied using observations from various instruments Golub at all 1979 have found that number of XBP anticorralates with sunspot number and suggested that solar cycle may be characterized as an oscillator in wavenumber space This finding prompted Yoshmura 1983 to suggest the existence of a secondary cycle of magnetic activity running in opposite phase to the sunspot cycle Later however Nakakubo Hara 2000 concluded that the variation in number of XBPs might be visibility effect as the enhanced brightness of corona may hinder identification of dimmer XBPs Sattarov at al 2002 found that while the number of bright points exhibit cyclic variation the number of magnetic bipoles with a particular flux and separation does not change from solar minimum to the maximum Hence Sattarov et al 2002 concluded that cyclic variation in XBP number may be a visibility effect In this work we continue study the properties of coronal bright points CBPs features that include XBPs and bright points in other wavelengths using SOHO EIT 195A data from 1996-2005 We identify CBPs using automatic procedure developed by us Sattarov et al 2005 Karachik et al 2006 and calculate various parameters including heliographic position intensity area and background intensity around each CBP Analyzing this data we found that the latitude-cycle variations of CBPs cannot be completely explained by the visibility effect These irregularities suggest that in addition to the isibility effect the actual number of coronal bright points on
- Publication:
-
36th COSPAR Scientific Assembly
- Pub Date:
- 2006
- Bibcode:
- 2006cosp...36..974S