Problem in Pythia output for multiparticle vertices -- fixed

[Johan Alwall]

Hi,

I'm trying to plug a new model with Feynrules/Madgraph5/Pythia8. Everything is ok until I want to make an output for pythia8 . The model uses 2 Fermion to 2 (Scalar/Fermion/Verctor) interactions in a 4 particle vertex.

The first message occurs when I try a e+ e- > s1+ s1- (Scalars) process:

Command "output pythia8" interrupted with error:
AttributeError : 'NoneType' object has no attribute 'get'
Please report this bug on https://bugs.launchpad.net/madgraph5
More information is found in 'MG5_debug'.
Please attach this file to your report.

The second message occurs when I try a e+ e- > e+ e- Process (as test):

Command "output pythia8" interrupted with error:
KeyError : ('FFSS1', 4)
Please report this bug on https://bugs.launchpad.net/madgraph5
More information is found in 'MG5_debug'.
Please attach this file to your report.

For the second there was a bug #861263, which is marked as solved. So I am nor sure if this is a question or a bug.

The Debug for the first is:

Traceback (most recent call last):
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/interface/extended_cmd.py", line 548, in onecmd
    return cmd.Cmd.onecmd(self, line)
  File "/usr/lib/python2.7/cmd.py", line 219, in onecmd
    return func(arg)
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/interface/master_interface.py", line 291, in do_output
    return self.cmd.do_output(self, *args, **opts)
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/interface/madgraph_interface.py", line 3289, in do_output
    self.export(nojpeg, main_file_name)
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/interface/madgraph_interface.py", line 3423, in export
    process_number = group_number, path = path)
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/iolibs/export_cpp.py", line 944, in generate_process_files_pythia8
    process_exporter_pythia8.generate_process_files()
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/iolibs/export_cpp.py", line 312, in generate_process_files
    self.write_process_h_file(writers.CPPWriter(filename))
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/iolibs/export_cpp.py", line 350, in write_process_h_file
    process_class_definitions = self.get_process_class_definitions()
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/iolibs/export_cpp.py", line 1015, in get_process_class_definitions
    replace_dict['resonances'] = self.get_resonance_lines()
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/iolibs/export_cpp.py", line 1170, in get_resonance_lines
    sids, singleres, schannel = self.get_resonances()
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/iolibs/export_cpp.py", line 1199, in get_resonances
    width = self.model.get_particle(sid).get('width')
AttributeError: 'NoneType' object has no attribute 'get'

For the second:

Traceback (most recent call last):
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/interface/extended_cmd.py", line 548, in onecmd
    return cmd.Cmd.onecmd(self, line)
  File "/usr/lib/python2.7/cmd.py", line 219, in onecmd
    return func(arg)
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/interface/master_interface.py", line 291, in do_output
    return self.cmd.do_output(self, *args, **opts)
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/interface/madgraph_interface.py", line 3289, in do_output
    self.export(nojpeg, main_file_name)
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/interface/madgraph_interface.py", line 3433, in export
    self._curr_model, self._export_dir)
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/iolibs/export_cpp.py", line 2085, in convert_model_to_pythia8
    model_builder.write_files()
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/iolibs/export_cpp.py", line 1643, in write_files
    self.write_aloha_routines()
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/madgraph/iolibs/export_cpp.py", line 1898, in write_aloha_routines
    aloha_model.compute_all(save=False)
  File "/net/home/lxtsfs1/tpe/mhuck/MadGraph5_v1_4_5/aloha/create_aloha.py", line 502, in compute_all
    self[(conjg_builder.name, outgoing)].add_combine(m)
KeyError: ('FFSS1', 4)

[Johan Alwall (johan-alwall)]

In fact, this was two bugs, one for the Pythia 8 matrix element output and one for the C++ ALOHA output. Both will be fixed in upcoming v. 1.4.6.

Many thanks MoritzHuck for reporting this.

All the best,
Johan