Neutrino interactions with pythia 8310

Never mind the branch name. This uses the latest pythia 8.310.

tests/modules/testPythia8.cpp

@@ -302,4 +302,36 @@ TEST_CASE("Pythia8Interface", "modules") {
                 {Proton::mass, {rootCS, {0_eV, 0_eV, 0_eV}}}) ==
             std::make_tuple(CrossSectionType::zero(), CrossSectionType::zero()));
   }
+
+  SECTION("pythia neutrino interaction") {
+
+    // this will be a nu-p collision at sqrts=3.5TeV -> no problem for pythia
+    auto [stackPtr, secViewPtr] = setup::testing::setup_stack(
+        Code::NuE, 7_TeV, (DummyEnvironment::BaseNodeType* const)nodePtr, *csPtr);
+    auto& view = *secViewPtr;
+
+    corsika::pythia8::NeutrinoInteraction collision(100_TeV, true);
+
+    REQUIRE(collision.isValid(
+        Code::NuE, Code::Proton,
+        {calculate_total_energy(100_TeV, NuE::mass), {rootCS, {0_eV, 0_eV, 100_TeV}}},
+        {Nitrogen::mass, {rootCS, {0_eV, 0_eV, 0_eV}}}));
+
+    REQUIRE(collision.getCrossSection(Code::NuE, Code::Proton,
+                                      {100_GeV, {rootCS, {0_eV, 0_eV, 100_GeV}}},
+                                      {Proton::mass, {rootCS, {0_eV, 0_eV, 0_eV}}}) !=
+            CrossSectionType::zero());
+
+    collision.doInteraction(
+        view, Code::NuE, Code::Nitrogen,
+        {calculate_total_energy(100_TeV, NuE::mass), {rootCS, {0_eV, 0_eV, 100_TeV}}},
+        {Nitrogen::mass, {rootCS, {0_eV, 0_eV, 0_eV}}});
+    REQUIRE(view.getSize() >= 2);
+
+    // no interaction for protons
+    REQUIRE(collision.getCrossSection(Code::Proton, Code::Proton,
+                                      {100_GeV, {rootCS, {0_eV, 0_eV, 100_GeV}}},
+                                      {Proton::mass, {rootCS, {0_eV, 0_eV, 0_eV}}}) ==
+            CrossSectionType::zero());
+  }
 }