FUNCTION DTC(VS,RS,W,P0)
C "DECAY TIME CONSTANT". TIME CONSTANT OF DECAY OF
C NEGATIVE PHASE BACK TO AMBIENT PRESSURE.
C	VS = SCHALLGESCHWINDIGKEIT IM GAS ZWISCHEN
C	     DEN ELEKTRODEN [M/S]
C	RS = MITTLERER KONTAKT-RADIUS [M]
C	 W = ENERGIE DER ENTLADUNG [J]
C	P0 = NORMALER GASDRUCK [PA]
C FORTRAN II
	FK5=1.
	DTC=(RS+.4(W/(FK5*P0)**(1./3.)))/VS
	RETURN
	END