deletions | additions       diff --git a/figures/fig_for_inclass_nova1/caption.tex b/figures/fig_for_inclass_nova1/caption.tex  index b6eeab4..64e775e 100644  --- a/figures/fig_for_inclass_nova1/caption.tex  +++ b/figures/fig_for_inclass_nova1/caption.tex 
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\label{ref:lab_inclass}  Figure supporting an in-class exercise, exercise on understanding image values and signal-to-noise,  carried out during the lab period. The students were asked to answer exercise itself consisted of  the following questions: following:  \begin{itshape}  Consider \emph{Consider  the attached image of a nova observed with the millimeter telescope CARMA at 96 GHz (Panel A). Histograms of pixel values are shown in Panels B and C (Panel C is just a zoom-in of a region on Panel B); these are just like the histograms you made in DS9's \verb|Scale Parameters|. The pixel values after calibration are expressed as flux density per pixel (units of mJy/pixel). The plotted range ($-2$ to 36 mJy/pixel) includes all pixels in the image. image.}  \noindent 1) Estimate the average background value ($\bar{S}$) and explain your reasoning.\\ 
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standard deviation of the background. In other words, the source's peak flux should be $S_{\rm max} > (\bar{S} + 5 \sigma$). Estimate how many sigma the peak flux density   of the nova is, and show your reasoning. Would this detection be taken seriously by   other astronomers?   \end{itshape}