After having read the WBS data with YODAT, you can get a light curve of the
count rate of the ratio of GRS-PHLi-j to GRS-PHLk-l with UTPLOT. This
works in a similar way to light curve of ratio of HXS-PHi-j to HXS-
PHk-l. For GRS-PHL1:
IDL> grsphl1=mk_grsphl1(index,data,xtime=xtime,channel=[i,j])
IDL> grsphl2=mk_grsphl1(index,data,xtime=xtime,channel=[k,l])
MK_GRSPHL1 is a function for making a float array of each of 128
GRS-PHL1 data. Next you extract background data.
IDL> bgph=out_grsphl1(index,data,/disp)
IDL> bgph=out_grsphl1(index,data,stime=stime)
OUT_GRSPHL1 is a function for output of the grs_phl1 data structure.
Now you subtract the background data and plot it.
IDL> subph1=grsphl1/4.0-total(bgph.signal(i:j))
IDL> subph2=grsphl2/4.0-total(bgph.signal(k:l))
IDL> utplot,xtime,subph2/subph1,index(0)
For GRS-PHL2, you can do a similar calculation using MK_GRSPHL2 and OUT_GRSPHL2.