Correct the description of REMOTEPARTDEL

control.asciidoc

@@ -155,9 +155,12 @@ MTSSUBSTEPS::
   increasing this value is the recommended way to reduce space charge
   solve frequency.
 REMOTEPARTDEL::
-  Artificially delete the remote particle if its distance to the beam
-  mass is larger than `REMOTEPARTDEL` times of the beam rms size, its
-  default values is -1 (no delete). Only used in _OPAL-cycl_.
+  Artificially delete remote particles if their distances to the beam
+  centroid is larger than `REMOTEPARTDEL` times of the beam rms size. The
+  default value is 0, i.e. no particles are deleted. In _OPAL-t_ only the 
+  longitudinal component of the particles is considered. In _OPAL-cycl_ all 
+  components are considered if the the value is negative (further on using its 
+  absolute value) and only the transverse components if the value is positive.
 RHODUMP::
   If true the scalar latexmath:[\rho] field is saved each time a phase
   space is written. There exists a reader in Visit with versions greater