First release

README.md

@@ -57,6 +57,12 @@ The current release of the proton response files is based on:
   * MOS: 1.5 - 11.5 keV
   * PN: 1.5 - 20 keV
 
+* The response files are available for three optical filters: 
+  * thin: 0.16 um of polyimide and 0.04 um of aluminium
+  * medium: 0.16 um of polyimide and 0.08 um of aluminium
+  * thick: 0.33 um of polypropylene, and 0.11 um of aluminium, and 0.045 um of tin
+
+
 <!-- LICENSE -->
 ## License