NED object is RX_J1211.2+3911; Reference is  2000ApJS..126..209R

   Figs. 98-134 show the source (light gray plus black) and background (dark
 gray) apertures used to define total count rates, cr_r_, for Bright SHARC
 clusters. Masked out pixels are shown in white. N.B.: The central black region
 represents the aperture used to define the wavelet count rates, cr_w_. Each
 image is 120 X 120 pixels, with a pixel scale of 14.947".