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: Image Synthesis : Example of Analysis Session : Choose an Event   目次

Light Curves

図 1: Light curves (Correlation plot)
\begin{figure}
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After choosing an event for analysis, see the light curves. It is useful to plot the correlation instead of the flux density. The method is as follows (Fig 1).
IDL> norh_rd_tcx,'1999-8-28',index,data $<$CR$>$
IDL> utplot,index,data,/ylog $<$CR$>$
Definition of 'correlation' is "averaged values of correlation of antenna pairs (after removing short base-line pairs) of NoRH". Correlation increases as a strong microwave signal comes due to e.g. a flare. So it is used instead of the real light curve (plot of flux density). For 17 GHz plot, 1 % of correlation corresponds to 30 SFU flux density. It is used because much computation resource is necessary for image synthesis that is the only method to obtain flux density at each time (see section 3.5.6). And correlation has an advantage that it is almost not affected by the weather condition. However, it does not increase when the flux is so strong because it has an upper limit of unity.


next up previous contents
: Image Synthesis : Example of Analysis Session : Choose an Event   目次
Takaaki YOKOYAMA 平成12年10月25日