RFC data model cross section

[tiborsimko]

We need a field where to store the cross section information.

One possibility is to use something simple:

   "cross_section": "0.001pb",

Another possibility is to use something more exapandable:

    "cross_section":  {
       "value": 0.001,
       "unit": "pb",
       "filter_efficiency": 1,
       "match_efficiency": 1,
       "description": "This is....",
       "note": "Please note..."
   }

CC @ArtemisLav @heitorPB @katilp

[heitorPB]

Unfortunately the unit is not available in the metadata we get from the databases. The values extracted differ in several orders of magnitude: from 0.01 to 23095400400.

From the ~3300 datasets (2010, 2011, 2012), only 24 have this information.

[tiborsimko]

Putting to Someday since the data is not ready yet.