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New Model Beynod the Standard Model Formulation

  1. Aug 19, 2012 #1

    I'm working on a new model beynod the standard model one of MSSM with B-L symmetry
    I'm trying to install CompHep (Event Generator) on Linux OS (Fedora 17)
    but always i get the same error

    gcc -o bin/tab_view.exe src/plot/view_tab.o -lnum -lserv -Llib -lX11 -lm -lg2c
    /usr/bin/ld: cannot find -lg2c
    collect2: ld returned 1 exit status
    make: *** [link] Error 1

    i have already installed
    2)libX11 package.
    3)g77 Compiler.

    I dont Know what is the Problem

    many thanks
  2. jcsd
  3. Aug 19, 2012 #2


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    Gold Member

    +1 to the B-L

    gfortran and gcc have packaging problems during the transition from gcc3.x to gcc4. Note I say "gfortran"; one of the problems was the change of flavour of the fortran compiler. It could help if you install or uninstall some packages in Fedora.
  4. Aug 19, 2012 #3
    i'm sorry i don't understand
    do you mean i must install gfortran
    can i talk you from E-mails
  5. Aug 19, 2012 #4
    Use a combination of madgraph 5 and the Feynrules mathematica package instead of CompHEP. You can just drop your lagrangian into Mathematica, and everything else is taken care of for you. Its much easier to use, especially if you aren't familiar with all the headaches that can arise because of the switch from g77 to gfortran. I think the Feynrules page even has an MSSM implementation that should be easy to modify for your purposes.
  6. Aug 19, 2012 #5
    Ok How can i implement such a model in mathematica
  7. Aug 19, 2012 #6


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    Yes I mean that depending of your version of gcc you can need either g77 or gfortran. I am sorry I do not remember the details.
  8. Aug 19, 2012 #7
    Ok thank you for your concern
  9. Aug 20, 2012 #8
    Download the feyrules package (google it). Download the MSSM implementation. Modify the lagrangian as necessary. Use the madgraph output format.

    To generate events, download madgraph 5, follow the instructions to point it to the output files from feynrules.
  10. Aug 20, 2012 #9

    Vanadium 50

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    One issue with MG/ME is that they use g77, f77 and gfortran, sometimes interchangably, sometimes not, and different gcc releases and different architectures treat those three aliases differently. In particular, 64-bit is usually a lot fussier than 32-bit. I don't think there is a simple solution, although running on a 32-bit machine usually helps.
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