diff --git a/matlab/TCV_IMAS/tcv_get_ids_core_sources.m b/matlab/TCV_IMAS/tcv_get_ids_core_sources.m
index 8a2236ca7deaaf410202a8fc3e2630d5980e9979..2e598bb85ce17983dcf90ac7092a7e5daabd0e20 100644
--- a/matlab/TCV_IMAS/tcv_get_ids_core_sources.m
+++ b/matlab/TCV_IMAS/tcv_get_ids_core_sources.m
@@ -200,7 +200,7 @@ if ~isempty(ec_gdat.ec.data) % if EC data available, fill sources
   production = 'TORAY';
   id_ec.index = 3; id_ec.name = 'ec';
   for i_lau = 1:nb_active
-    id_ec.description = sprintf('L%i/G%i, %s from %s double width CD profiles',i_lau,ec_inputs.gyro2launcher.data(i_lau),main_desc,production);
+    id_ec.description = sprintf('L%i/G%i, %s from %s double width CD profiles',active_launchers(i_lau),ec_inputs.gyro2launcher.data(active_launchers(i_lau)),main_desc,production);
     ids_core_sources.source{last_index+i_lau} = source_template;
     ids_core_sources.source{last_index+i_lau}.identifier = id_ec;
     ids_core_sources.source{last_index+i_lau}.profiles_1d(1:nt_ec_out) = {profiles_template};