more refinements to the example notebook

docs/tutorials/background_estimation/continuum_estimation/BG_estimation_example.ipynb

@@ -315,7 +315,7 @@
    "source": [
     "# Detector response file\n",
     "# Make sure to unzip file after downloading!\n",
-    "fetch_wasabi_file('COSI-SMEX/DC2/Responses/SMEXv12.Continuum.HEALPixO3_10bins_log_flat.binnedimaging.imagingresponse.nonsparse_nside8.area.good_chunks_unzip.h5.zip')"
+    "fetch_wasabi_file('COSI-SMEX/DC2/Responses/SMEXv12.Continuum.HEALPixO3_10bins_log_flat.binnedimaging.imagingresponse.nonsparse_nside8.area.good_chunks_unzip.earthocc.h5.zip')"
    ]
   },
   {
@@ -401,7 +401,9 @@
    "id": "25c9e430-05c7-4119-bc05-ec025223c237",
    "metadata": {},
    "source": [
-    "Now let's calculate the estimated background. To make a short example, we'll only consider 1 Em bin and 2 Phi bins, as specified by the optional keywords e_loop and s_loop, respectively. We'll also make plots here for demonstrational purposes. "
+    "Now let's calculate the estimated background. To make a short example, we'll only consider 1 Em bin and 2 Phi bins, as specified by the optional keywords e_loop and s_loop, respectively. We'll also make plots here for demonstrational purposes. \n",
+    "\n",
+    "Note that the current code has not yet been optimized for speed, as it uses a simple nested for loop. The time required to generate the estimated background using all bins is roughyly 4 hours. The option to use a subset of the Em bins and/or Phi bins may be useful for analyses that also use a given subset, but at this point the main motivation for this option is for demonstrational purposes, and when using this option, nothing is done with the other bins. "
    ]
   },
   {