The Collaborative International Dictionary of English v.0.48:

Impanelment \Im*pan"el*ment\, n.
   The act or process of impaneling, or the state of being
   impaneled.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

26 Moby Thesaurus words for "impanelment":
   booking, cataloging, chronicling, enlistment, enrollment, entering,
   entry, indexing, inscribing, inscription, insertion, inventorying,
   jury selection, listing, logging, matriculation, posting,
   record keeping, recordation, recording, register, registration,
   registry, tabulation, venire, venire facias