import org.jfree.ui.RectangleAnchor as RectangleAnchor
import org.jfree.ui.TextAnchor as TextAnchor
p=plot(None)[0]
m1=p.addMarker(0,None,"",Color.WHITE)
m2=p.addMarker(0,None,"",Color.WHITE)
m2.setLabelAnchor(RectangleAnchor.TOP) 
while True:
    p.getSeries(0).setData(psss_spectrum_x.take(), psss_spectrum_y.take())  
    m1.value, m2.value =  psss_center.take() - psss_fwhm.take(),psss_center.take() + psss_fwhm.take()
    m2.label = str(psss_center.take())    
    time.sleep(1.0)