diff --git a/src/phase_mechanical_plastic_dislotwin.f90 b/src/phase_mechanical_plastic_dislotwin.f90
index 6a9043cde..e1ccf3f5f 100644
--- a/src/phase_mechanical_plastic_dislotwin.f90
+++ b/src/phase_mechanical_plastic_dislotwin.f90
@@ -940,7 +940,6 @@ pure subroutine kinetics_tw(Mp,T,dot_gamma_sl,ph,en,&
     ddot_gamma_dtau_tw
 
   real :: &
-    ratio_tau_r, &
     tau, tau_r, &
     dot_N_0, &
     x0, &
@@ -966,9 +965,8 @@ pure subroutine kinetics_tw(Mp,T,dot_gamma_sl,ph,en,&
         tau_r = mu*prm%b_tw(i)/(2.0_pReal*PI)*(1.0_pReal/(x0+prm%x_c_tw)+cos(PI/3.0_pReal)/x0)      ! ToDo: In the paper, the Burgers vector for slip is used
 
         if (tau > tol_math_check .and. tau < tau_r) then
-          ratio_tau_r = (dst%tau_hat_tw(i,en)/tau)**prm%r(i)
-          P = exp(-ratio_tau_r)
-          dP_dTau = prm%r(i) * ratio_tau_r/tau * P
+          P = exp(-(dst%tau_hat_tw(i,en)/tau)**prm%r(i))
+          dP_dTau = prm%r(i) * (dst%tau_hat_tw(i,en)/tau)**prm%r(i)/tau * P
 
           s = prm%fcc_twinNucleationSlipPair(1:2,i)
           dot_N_0 = sum(abs(dot_gamma_sl(s(2:1:-1)))*(stt%rho_mob(s,en)+stt%rho_dip(s,en))) &
@@ -1031,7 +1029,6 @@ pure subroutine kinetics_tr(Mp,T,dot_gamma_sl,ph,en,&
     ddot_gamma_dtau_tr
 
   real :: &
-    ratio_tau_s, &
     tau, tau_r, &
     dot_N_0, &
     x0, &
@@ -1056,9 +1053,8 @@ pure subroutine kinetics_tr(Mp,T,dot_gamma_sl,ph,en,&
       tau_r = mu*prm%b_tr(i)/(2.0_pReal*PI)*(1.0_pReal/(x0+prm%x_c_tr)+cos(PI/3.0_pReal)/x0)        ! ToDo: In the paper, the Burgers vector for slip is used
 
       if (tau > tol_math_check .and. tau < tau_r) then
-        ratio_tau_s = (dst%tau_hat_tr(i,en)/tau)**prm%s(i)
-        P = exp(-ratio_tau_s)
-        dP_dTau = prm%s(i) * ratio_tau_s/tau * P
+        P = exp(-(dst%tau_hat_tr(i,en)/tau)**prm%s(i))
+        dP_dTau = prm%s(i) * (dst%tau_hat_tr(i,en)/tau)**prm%s(i)/tau * P
 
         s = prm%fcc_twinNucleationSlipPair(1:2,i)
         dot_N_0 = sum(abs(dot_gamma_sl(s(2:1:-1)))*(stt%rho_mob(s,en)+stt%rho_dip(s,en))) &