This data record optionally defines a name for a spectral group. It is associated with the currently defined Spectral Group.

      2   5  7   11         21
    - --- -- ---- ---------- ----------
   |X|   |  |SGNM|XXXXXXXXXX|          |
    - --- -- ---- ---------- ----------
       |  |   |                 |
       |  |   |                 |_(2) Name for this Spectral Group
       |  |   |
       |  |   |_(1) Compulsory Data Record Keyword(A4)
       |  |
       |  |_Optional User Identifier (A2)
       |
       |_Compulsory END on last data record in Data Category (A3)