| 210 | |

| 211 | Notice that if the "background" tree-level structure is very different than the loop-induced ones you are interfering against, then it might be a good idea to add the corresponding tree-level topologies to the multi-channel. |

| 212 | This can be achieved with the following small modifications. Around line 104 of the file '<MG_root_path>/madgraph/various/diagram_symmetry.py' , to the lines |

| 213 | {{{ |

| 214 | base_diagrams = base_objects.DiagramList( |

| 215 | [(d.get_contracted_loop_diagram(base_model,FDStructRepo) if |

| 216 | isinstance(d,loop_base_objects.LoopDiagram) else d) for d in |

| 217 | matrix_element.get('base_amplitude').get('loop_diagrams') \ |

| 218 | if d.get('type')>0]) |

| 219 | diagrams = matrix_element.get_loop_diagrams() |

| 220 | }}} |

| 221 | Add the following ones right below: |

| 222 | {{{ |

| 223 | base_diagrams.extend([(d.get_contracted_loop_diagram(base_model,FDStructRepo) if |

| 224 | isinstance(d,loop_base_objects.LoopUVCTDiagram) else d) for d in |

| 225 | matrix_element.get('base_amplitude').get('loop_UVCT_diagrams')]) |

| 226 | diagrams.extend(matrix_element.get_loop_UVCT_diagrams()) |

| 227 | }}} |

| 228 | And then around the line 317 of '<MG_root_path>/madgraph/iolibs/group_subprocs.py' , to the line |

| 229 | {{{ |

| 230 | diagrams = [(d.get_contracted_loop_diagram(model,FDStructRepo) if |

| 231 | isinstance(d,loop_base_objects.LoopDiagram) else d) for d in |

| 232 | me.get('base_amplitude').get('loop_diagrams') if d.get('type')>0] |

| 233 | }}} |

| 234 | Add the following one, right below: |

| 235 | {{{ |

| 236 | diagrams.extend([(d.get_contracted_loop_diagram(model,FDStructRepo) if |

| 237 | isinstance(d,loop_base_objects.LoopUVCTDiagram) else d) for d in |

| 238 | me.get('base_amplitude').get('loop_UVCT_diagrams')]) |

| 239 | }}} |

| 240 | Finally, when using these modifications and in order to activate all these extra integration channels, you must set |

| 241 | {{{ |

| 242 | MG5_aMC>set group_subprocesses False |

| 243 | }}} |

| 244 | before the generation of your process (irrespectively of your MG5aMC distribution this time). |