getting zero result

Hi,

Did you cross-check that your CKM matrix is non diagonal?
Otherwise I suppose that your results is indeed analytically zero and that madgraph returns the correct answer.

Cheers,

Olivier

> On Mar 30, 2016, at 08:27, SUBHASISH BEHERA <email address hidden> wrote:
>
> Question #289539 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/289539
>
> Description changed to:
> Dear MG5 Team,
> I have import a model "topFCNC" which can be found here : https://feynrules.irmp.ucl.ac.be/wiki/GeneralFCNTop#no1
>
> I was generating a process : define j = j b b~
> generate p p > t j , (t > w+ b) NP=99 QED=99
>
>
> After this I launch the process which some changes in Param card like : CM energy : "7 Tev" and no o fevents to "50000" and pdf set to "cteq6l1" and then run the process with pythia remain on.
>
> Surprisingly I am getting the following error with zero result. I have
> gone through the faq but unable to understand "How to come out of it ?"
> The following error occurs :
>
>
>> 0
> Generating 50000 events with run name run_01
> survey run_01
> INFO: compile directory
> compile Source Directory
> Using random number seed offset = 21
> INFO: Running Survey
> Creating Jobs
> Working on SubProcesses
> INFO: P1_gg_tux_t_wpb
> INFO: P1_gg_tcx_t_wpb
> INFO: P1_gu_tg_t_wpb
> INFO: P1_gc_tg_t_wpb
> INFO: P1_uu_tu_t_wpb
> INFO: P1_uc_tu_t_wpb
> INFO: P1_uc_tc_t_wpb
> INFO: P1_ud_td_t_wpb
> INFO: P1_us_ts_t_wpb
> INFO: P1_uux_tcx_t_wpb
> INFO: P1_cc_tc_t_wpb
> INFO: P1_cd_td_t_wpb
> Note: The following floating-point exceptions are signalling: IEEE_INVALID_FLAG
> INFO: P1_cs_ts_t_wpb
> INFO: P1_cux_tux_t_wpb
> INFO: P1_ccx_tux_t_wpb
> INFO: P1_ddx_tux_t_wpb
> INFO: P1_ddx_tcx_t_wpb
> INFO: P1_ssx_tux_t_wpb
> INFO: P1_ssx_tcx_t_wpb
> INFO: Idle: 0, Running: 2, Completed: 39 [ current time: 19h45 ]
> INFO: Idle: 0, Running: 1, Completed: 40 [ 7.9s ]
> INFO: Idle: 0, Running: 0, Completed: 41 [ 9.2s ]
> INFO: End survey
> refine 50000
> Creating Jobs
> INFO: Refine results to 50000
> INFO: Generating 50000.0 unweigthed events.
> INFO: Effective Luminosity 6e+103 pb^-1
> INFO: need to improve 0 channels
> Survey return zero cross section.
> Typical reasons are the following:
> 1) A massive s-channel particle has a width set to zero.
> 2) The pdf are zero for at least one of the initial state particles
> or you are using maxjetflavor=4 for initial state b:s.
> 3) The cuts are too strong.
> Please check/correct your param_card and/or your run_card.
> Zero result detected: See https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/FAQ-General-14
> INFO:
>
> INFO:
>
> quit
> INFO:
>
> INFO:
>
> more information in /home/users/rs/subhasish/Research/EVENT_GENERATORS/MG5_aMC_v2_3_3/Fpp2tj/index.html
> MG5_aMC>>0
> Generating 50000 events with run name run_01
> survey run_01
> INFO: compile directory
> compile Source Directory
> Using random number seed offset = 21
> INFO: Running Survey
> Creating Jobs
> Working on SubProcesses
> INFO: P1_gg_tux_t_wpb
> INFO: P1_gg_tcx_t_wpb
> INFO: P1_gu_tg_t_wpb
> INFO: P1_gc_tg_t_wpb
> INFO: P1_uu_tu_t_wpb
> INFO: P1_uc_tu_t_wpb
> INFO: P1_uc_tc_t_wpb
> INFO: P1_ud_td_t_wpb
> INFO: P1_us_ts_t_wpb
> INFO: P1_uux_tcx_t_wpb
> INFO: P1_cc_tc_t_wpb
> INFO: P1_cd_td_t_wpb
> Note: The following floating-point exceptions are signalling: IEEE_INVALID_FLAG
> INFO: P1_cs_ts_t_wpb
> INFO: P1_cux_tux_t_wpb
> INFO: P1_ccx_tux_t_wpb
> INFO: P1_ddx_tux_t_wpb
> INFO: P1_ddx_tcx_t_wpb
> INFO: P1_ssx_tux_t_wpb
> INFO: P1_ssx_tcx_t_wpb
> INFO: Idle: 0, Running: 2, Completed: 39 [ current time: 19h45 ]
> INFO: Idle: 0, Running: 1, Completed: 40 [ 7.9s ]
> INFO: Idle: 0, Running: 0, Completed: 41 [ 9.2s ]
> INFO: End survey
> refine 50000
> Creating Jobs
> INFO: Refine results to 50000
> INFO: Generating 50000.0 unweigthed events.
> INFO: Effective Luminosity 6e+103 pb^-1
> INFO: need to improve 0 channels
> Survey return zero cross section.
> Typical reasons are the following:
> 1) A massive s-channel particle has a width set to zero.
> 2) The pdf are zero for at least one of the initial state particles
> or you are using maxjetflavor=4 for initial state b:s.
> 3) The cuts are too strong.
> Please check/correct your param_card and/or your run_card.
> Zero result detected: See https://cp3.irmp.ucl.ac.be/projects/madgraph/wiki/FAQ-General-14
> INFO:
>
> INFO:
>
> quit
> INFO:
>
> INFO:
>
> more information in /home/users/rs/subhasish/Research/EVENT_GENERATORS/MG5_aMC_v2_3_3/Fpp2tj/index.html
> MG5_aMC>
>
>
> Thanks,
>
> Subhasish
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Dear Olivier,
        The model ".nb" file don't take ckm.rst into account, as you can see from its site. It only load the "SM.fr" and "topFCNC.fr" files only. Thus the CKM matrix is non diagonal I believe !!! Am I right ?

Thanks,

Subhasish

Thanks Olivier Mattelaer, that solved my question.