diff --git a/FixedOrderGen/t/CMakeLists.txt b/FixedOrderGen/t/CMakeLists.txt
index f4294fb..9503a66 100644
--- a/FixedOrderGen/t/CMakeLists.txt
+++ b/FixedOrderGen/t/CMakeLists.txt
@@ -1,108 +1,128 @@
 set(tst_dir "${CMAKE_CURRENT_SOURCE_DIR}")
 foreach(tst W_reconstruct_enu W_2j_classify W_nj_classify)
   add_executable(test_${tst} ${tst_dir}/${tst}.cc)
   target_link_libraries(test_${tst} hejfog_lib)
   add_test(NAME ${tst} COMMAND test_${tst} WORKING_DIRECTORY ${tst_dir})
 endforeach()
 # this only tests if the runcard actually works, not if the result is correct
 add_test(
   NAME main_2j
   COMMAND HEJFOG ${tst_dir}/config_2j.yml
   )
 add_test(
   NAME main_h2j
   COMMAND HEJFOG ${tst_dir}/config_h2j.yml
   )
 add_test(
   NAME main_h2j_decay
   COMMAND HEJFOG ${tst_dir}/config_h2j_decay.yml
   )
 add_test(
   NAME peakpt
   COMMAND HEJFOG ${tst_dir}/config_2j_peak.yml
   )
 
 # check that uno emission doesn't change FKL xs
 add_executable(FKL_uno FKL_uno.cc)
 target_link_libraries(FKL_uno hejfog_lib)
 add_test(
   NAME FKL_uno
   # calculated with HEJ revision 9570e3809613272ac4b8bf3236279ba23cf64d20
   COMMAND FKL_uno ${tst_dir}/config_h3j_uno.yml 0.0243548 0.000119862
 )
 # xs tests
 add_executable(xs_gen xs_gen.cc)
 target_link_libraries(xs_gen hejfog_lib)
 ## Higgs
 add_test(
   NAME xs_h2j
   # calculated with HEJ revision 9570e3809613272ac4b8bf3236279ba23cf64d20
   COMMAND xs_gen ${tst_dir}/config_h2j.yml 2.04928 0.00956022
 )
 add_test(
   NAME xs_h3j
   # calculated with HEJ revision bd4388fe55cbc3f5a7b6139096456c551294aa31
   COMMAND xs_gen ${tst_dir}/config_h3j.yml 1.07807 0.0132409
 )
 add_test(
   NAME xs_h5j
   # calculated with HEJ revision dbde2ffbb3b383ae6709b2424d8f0f9d5658270b
   COMMAND xs_gen ${tst_dir}/config_h5j.yml 0.0112504 0.000199633
 )
 add_test(
   NAME xs_h3j_uno
   # calculated with HEJ revision 9570e3809613272ac4b8bf3236279ba23cf64d20
   COMMAND xs_gen ${tst_dir}/config_h3j_uno.yml 0.00347538 3.85875e-05
 )
 add_test(
   NAME xs_h2j_decay
   # calculated with HEJ revision 9570e3809613272ac4b8bf3236279ba23cf64d20
   COMMAND xs_gen ${tst_dir}/config_h2j_decay.yml 0.00466994 2.20995e-05
 )
 ## pure jets
 add_test(
   NAME xs_2j
   # calculated with "combined" HEJ svn r3480
   COMMAND xs_gen ${tst_dir}/config_2j.yml 86.42031848e06 590570
 )
 add_test(
   NAME xs_3j_uno
   # calculated with HEJ revision 9401196fba75b5d16bc33f2a309175fecaca00f1
   COMMAND xs_gen ${tst_dir}/config_3j_uno.yml 900 14.3131
 )
 add_test(
   NAME xs_3j_qqx
   # calculated with HEJ revision 9401196fba75b5d16bc33f2a309175fecaca00f1
   COMMAND xs_gen ${tst_dir}/config_3j_qqx.yml 62040 1005
 )
 add_test(
   NAME xs_4j_qqx
   # calculated with HEJ revision 9401196fba75b5d16bc33f2a309175fecaca00f1
   COMMAND xs_gen ${tst_dir}/config_4j_qqx.yml 28936 550
 )
 add_test(
   NAME xs_4j
   # calculated with HEJ revision 13207b5f67a5f40a2141aa7ee515b022bd4efb65
   COMMAND xs_gen ${tst_dir}/config_4j.yml 915072 15402.4
 )
 ## W
 add_test(
   NAME xs_W2j
   # calculated with HEJ revision 987bb30a7985a24a7961f98cfbbc74d3a7992970
   COMMAND xs_gen ${tst_dir}/config_Wm2j.yml 231.404 3.43798
 )
 add_test(
   NAME xs_W3j_uno
   # calculated with HEJ revision 996f728a56ed67b980fccbe79948fe56914aaccd+1
   COMMAND xs_gen ${tst_dir}/config_Wp3j_uno.yml 0.295275 0.0056667
 )
 add_test(
   NAME xs_W3j_eqqx
   # calculated with HEJ revision 987bb30a7985a24a7961f98cfbbc74d3a7992970
   COMMAND xs_gen ${tst_dir}/config_Wp3j_qqx.yml 8.45323 0.103449
 )
 add_test(
   NAME xs_W4j_qqx
   # calculated with HEJ revision 987bb30a7985a24a7961f98cfbbc74d3a7992970
   COMMAND xs_gen ${tst_dir}/config_Wp4j_qqx.yml 0.0851908 0.00300447
 )
+
+# PSP tests
+add_executable(PSP_channel PSP_channel.cc)
+target_link_libraries(PSP_channel hejfog_lib)
+add_test(
+  NAME channel_2j
+  COMMAND PSP_channel ${tst_dir}/config_2j.yml
+)
+add_test(
+  NAME channel_3j_qqx
+  COMMAND PSP_channel ${tst_dir}/config_3j_qqx.yml
+)
+add_test(
+  NAME channel_3j_uno
+  COMMAND PSP_channel ${tst_dir}/config_3j_uno.yml
+)
+add_test(
+  NAME channel_4j_qqx
+  COMMAND PSP_channel ${tst_dir}/config_4j_qqx.yml
+)
diff --git a/FixedOrderGen/t/PSP_channel.cc b/FixedOrderGen/t/PSP_channel.cc
new file mode 100644
index 0000000..2c2e494
--- /dev/null
+++ b/FixedOrderGen/t/PSP_channel.cc
@@ -0,0 +1,172 @@
+/**
+ *  check that the sum of all possible quarks is the same as a proton
+ *
+ *  \authors   The HEJ collaboration (see AUTHORS for details)
+ *  \date      2020
+ *  \copyright GPLv2 or later
+ */
+#include <array>
+#include <iostream>
+#include <memory>
+
+#include "HEJ/Mixmax.hh"
+#include "HEJ/Event.hh"
+
+#include "config.hh"
+#include "EventGenerator.hh"
+
+//! throw error if condition not fulfilled
+#define ASSERT(x) if(!(x)) { \
+    throw std::logic_error("Assertion '" #x "' failed."); \
+  }
+
+//! throw error if condition not fulfilled
+#define ASSERT_THROW(x, exception) try { \
+      x; \
+      std::cerr << "'" #x "' did not throw an exception.\n"; \
+      throw; \
+    } catch(exception const & ex){ \
+      std::cout << "throw triggered: " << ex.what() << std::endl; \
+    } \
+    catch (...) { \
+      std::cerr << "Unexpected exception thrown for '" #x "'.\n"; \
+      throw; \
+    }
+
+namespace {
+
+  HEJFOG::EventGenerator make_generator(
+    HEJFOG::Config const & config,
+    std::shared_ptr<HEJ::RNG> ran
+  ){
+    return HEJFOG::EventGenerator{
+      config.process,
+      config.beam,
+      HEJ::ScaleGenerator{
+        config.scales.base,
+        config.scales.factors,
+        config.scales.max_ratio
+      },
+      config.jets,
+      config.pdf_id,
+      config.subleading_fraction,
+      config.subleading_channels,
+      config.particle_decays,
+      config.Higgs_coupling,
+      config.ew_parameters,
+      ran
+    };
+  }
+
+  const static std::array<HEJ::ParticleID, 11> PARTONS{
+    HEJ::ParticleID::g,
+    HEJ::ParticleID::d, HEJ::ParticleID::u,
+    HEJ::ParticleID::s, HEJ::ParticleID::c,
+    HEJ::ParticleID::b,
+    HEJ::ParticleID::d_bar, HEJ::ParticleID::u_bar,
+    HEJ::ParticleID::s_bar, HEJ::ParticleID::c_bar,
+    HEJ::ParticleID::b_bar
+  };
+
+  bool only_channel(
+    HEJFOG::Subleading channels,
+    HEJFOG::subleading::Channels selected
+  ){
+    return channels[selected] && channels.reset(selected).none();
+  }
+
+  void generate_till_throw(HEJFOG::EventGenerator & gen ){
+    for(std::size_t i=0; i<100; ++i){
+        auto ev = gen.gen_event();
+        if(gen.status()==HEJFOG::Status::good){
+          std::cerr << "Wrongfully generated valid event!" << *ev <<"\n";
+          throw;
+        }
+    }
+    std::cerr << "Unable to generate a proper throw!\n";
+    throw;
+  }
+}
+
+int main(int argc, char const *argv[])
+{
+  if(argc != 2){
+    std::cerr << "Usage: " << argv[0] << " config.yaml\n";
+    return EXIT_FAILURE;
+  }
+  std::cout <<std::scientific;
+
+  auto config = HEJFOG::load_config(argv[1]);
+  config.events = 100000;
+  auto ran = std::make_shared<HEJ::Mixmax>();
+
+  double tot_weight = 0.;
+  double tot_err = 0.;
+  config.process.incoming[0] = config.process.incoming[1] = HEJ::ParticleID::proton;
+  {
+    HEJFOG::EventGenerator gen = make_generator(config, ran);
+    for(std::size_t i=0; i<config.events; ++i){
+      auto const ev = gen.gen_event();
+      if(ev){
+        double const wgt = ev->central().weight/config.events;
+        tot_weight += wgt;
+        tot_err += wgt*wgt;
+      }
+    }
+
+  }
+  tot_err = std::sqrt(tot_err);
+
+
+  config.events /= PARTONS.size();
+  double tot_channels = 0.;
+  double err_channels = 0.;
+  for(auto b1: PARTONS){
+    for(auto b2: PARTONS){
+      double wgt_channel = 0.;
+      double err_channel = 0.;
+      config.process.incoming[0] = b1;
+      config.process.incoming[1] = b2;
+      HEJFOG::EventGenerator gen = make_generator(config, ran);
+      std::cout << name(b1) << "+" << name(b2) << " " <<std::flush;
+      // for pure subleading configurations some setups states should throw
+      if(config.subleading_fraction == 1.){
+        if( only_channel(config.subleading_channels, HEJFOG::subleading::uno) ){
+          if(HEJ::is_gluon(b1) && HEJ::is_gluon(b2)){
+            std::cout << "uno" << std::endl;
+            ASSERT_THROW(generate_till_throw(gen), std::invalid_argument);
+            continue;
+          }
+        }
+        if( only_channel(config.subleading_channels, HEJFOG::subleading::eqqx) ){
+          if(HEJ::is_anyquark(b1) && HEJ::is_anyquark(b2)){
+            std::cout << "eqqx" << std::endl;
+            ASSERT_THROW(generate_till_throw(gen), std::invalid_argument);
+            continue;
+          }
+        }
+      }
+      for(std::size_t i=0; i<config.events; ++i){
+        // everything else should work
+        auto const ev = gen.gen_event();
+        if(ev){
+          double const wgt = ev->central().weight/config.events;
+          wgt_channel += wgt;
+          err_channel += wgt*wgt;
+        }
+      }
+      tot_channels += wgt_channel;
+      err_channels += err_channel;
+      err_channel = std::sqrt(err_channel);
+      std::cout << "=> " << wgt_channel << " +/- " << err_channel << std::endl;
+    }
+  }
+  err_channels = std::sqrt(err_channels);
+  std::cout << tot_weight << " +/- " << tot_err
+    << " vs. " << tot_channels << " +/- " << err_channels << std::endl;
+
+  ASSERT(std::abs(tot_weight - tot_channels)
+    < 2.*sqrt(err_channels*err_channels+tot_err*tot_err));
+
+  return EXIT_SUCCESS;
+}