diff --git a/src/core/lb/particle_coupling.hpp b/src/core/lb/particle_coupling.hpp
index bacdd1061f..d5e7cdf3a5 100644
--- a/src/core/lb/particle_coupling.hpp
+++ b/src/core/lb/particle_coupling.hpp
@@ -32,7 +32,6 @@
 #include <utils/Vector.hpp>
 #include <utils/math/sqr.hpp>
 
-#include <cassert>
 #include <cmath>
 #include <unordered_set>
 #include <vector>
@@ -93,17 +92,16 @@ class ParticleCoupling {
 public:
   ParticleCoupling(LBThermostat const &thermostat, LB::Solver &lb,
                    BoxGeometry const &box_geo, LocalBox const &local_box,
-                   double time_step, double kT = -1.)
+                   double time_step)
       : m_thermostat{thermostat}, m_lb{lb}, m_box_geo{box_geo},
         m_local_box{local_box}, m_time_step{time_step} {
-    assert(kT >= 0. or kT == -1.);
     /* Eq. (16) @cite ahlrichs99a, without the gamma term.
      * The factor 12 comes from the fact that we use random numbers
      * from -0.5 to 0.5 (equally distributed) which have variance 1/12.
      * The time step comes from the discretization.
      */
     auto constexpr variance_inv = 12.;
-    kT = (kT >= 0.) ? kT : lb.get_kT() * Utils::sqr(lb.get_lattice_speed());
+    auto const kT = lb.get_kT() * Utils::sqr(lb.get_lattice_speed());
     m_thermalized = (kT != 0.);
     m_noise_pref_wo_gamma = std::sqrt(variance_inv * 2. * kT / time_step);
   }
diff --git a/src/core/unit_tests/lb_particle_coupling_test.cpp b/src/core/unit_tests/lb_particle_coupling_test.cpp
index 2d4e6893dc..542587dc89 100644
--- a/src/core/unit_tests/lb_particle_coupling_test.cpp
+++ b/src/core/unit_tests/lb_particle_coupling_test.cpp
@@ -175,12 +175,13 @@ BOOST_AUTO_TEST_CASE(rng) {
   auto &thermostat = *espresso::system->thermostat->lb;
   auto const &box_geo = *espresso::system->box_geo;
   auto const &local_box = *espresso::system->local_geo;
+  auto const tau = params.time_step;
   thermostat.rng_initialize(17u);
   thermostat.set_rng_counter(11ul);
   thermostat.gamma = 0.2;
+  espresso::set_lb_kT(1.);
 
-  LB::ParticleCoupling coupling{thermostat,       lb, box_geo, local_box,
-                                params.time_step, 1.};
+  LB::ParticleCoupling coupling{thermostat, lb, box_geo, local_box, tau};
   BOOST_CHECK_EQUAL(thermostat.rng_seed(), 17u);
   BOOST_CHECK_EQUAL(thermostat.rng_counter(), 11ul);
   BOOST_CHECK(not thermostat.is_seed_required());
@@ -206,8 +207,9 @@ BOOST_AUTO_TEST_CASE(rng) {
   BOOST_CHECK(step1_random1 != step2_random1);
   BOOST_CHECK(step1_random1 != step2_random2);
 
-  LB::ParticleCoupling coupling_unthermalized{
-      thermostat, lb, box_geo, local_box, params.time_step, 0.};
+  espresso::set_lb_kT(0.);
+  LB::ParticleCoupling coupling_unthermalized{thermostat, lb, box_geo,
+                                              local_box, tau};
   auto const step3_norandom =
       coupling_unthermalized.get_noise_term(test_partcl_2);
   BOOST_CHECK((step3_norandom == Utils::Vector3d{0., 0., 0.}));
diff --git a/src/script_interface/thermostat/thermostat.hpp b/src/script_interface/thermostat/thermostat.hpp
index 1125f04200..c2494362d8 100644
--- a/src/script_interface/thermostat/thermostat.hpp
+++ b/src/script_interface/thermostat/thermostat.hpp
@@ -146,9 +146,9 @@ class Interface : public AutoParameters<Interface<CoreClass>, System::Leaf> {
 #ifdef PARTICLE_ANISOTROPY
           static_assert(std::is_same_v<T, Utils::Vector3d>);
           T gamma{};
-          try {
+          if (is_type<int>(v) or is_type<double>(v)) {
             gamma = T::broadcast(get_value<double>(v));
-          } catch (...) {
+          } else {
             gamma = get_value<T>(v);
           }
 #else