File with 0 momentum and mass (tW channel)

Asked by Jazmine Jefferson on 2018-06-11

I have been attempting to generate a single top tW channel decay in mg5 using the following commands:
>import model loop-sm_no-b-mass
>generate p p > t w-, w- > mu- vm~
>add process p p > t~ w+, w+ > mu+ vm
>output
>launch

It generates a root file where half of the ts and mus have 0 momentum and 0 mass. Would appreciate any input.

Question information

Language:
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Status:
Answered
For:
MadGraph5_aMC@NLO Edit question
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Last query:
2018-06-15
Last reply:
2018-06-15

Can you check the lhe file.
We do not produce root file ourself.
So the first step is to check if our lhe file is correct or not.
If it is, I would need to know how you create your root file in order to be able to comment.

Cheers,

Olivier

> On 12 Jun 2018, at 00:08, Jazmine Jefferson <email address hidden> wrote:
>
> New question #670144 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/670144
>
> I have been attempting to generate a single top tW channel decay in mg5 using the following commands:
>> import model loop-sm_no-b-mass
>> generate p p > t w-, w- > mu- vm~
>> add process p p > t~ w+, w+ > mu+ vm
>> output
>> launch
>
> It generates a root file where half of the ts and mus have 0 momentum and 0 mass. Would appreciate any input.
>
>
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Jazmine Jefferson (jjeffers) said : #2

The LHEF shows the same issue, and then I simply use ExRootAnalysis to convert to the root file

Hi,

First the command:
> import model loop-sm_no-b-mass
does not correspond to any know model.
So I have try with
> import model loop_sm-no_b_mass
If this is not the model that you are using, please send me your model such that I can reproduce your run

Therefore I have run the following script:

> import model loop_sm-no_b_mass
> generate p p > t w-, w- > mu- vm~
> add process p p > t~ w+, w+ > mu+ vm
> output
> launch

I put below some of the events that are produced:

> <event>
> 6 1 +6.0227000e+00 2.11564900e+02 7.54677100e-03 1.15596600e-01
> 21 -1 0 0 501 502 +0.0000000000e+00 +0.0000000000e+00 +1.0758056114e+03 1.0758056114e+03 0.0000000000e+00 0.0000e+00 -1.0000e+00
> 5 -1 0 0 502 0 -0.0000000000e+00 -0.0000000000e+00 -3.0438170672e+01 3.0438170672e+01 0.0000000000e+00 0.0000e+00 -1.0000e+00
> -24 2 1 2 0 0 +4.6909363183e+01 -1.1238424165e+02 +5.1409390645e+02 5.3439478597e+02 8.0340130021e+01 0.0000e+00 0.0000e+00
> 6 1 1 2 501 0 -4.6909363183e+01 +1.1238424165e+02 +5.3127353428e+02 5.7184899611e+02 1.7300000000e+02 0.0000e+00 -1.0000e+00
> 13 1 3 3 0 0 +6.4181954667e+01 -9.0239787708e+01 +3.2787737519e+02 3.4607241403e+02 0.0000000000e+00 0.0000e+00 -1.0000e+00
> -14 1 3 3 0 0 -1.7272591484e+01 -2.2144453943e+01 +1.8621653127e+02 1.8832237194e+02 0.0000000000e+00 0.0000e+00 1.0000e+00

so here top mass is 173, the muon mass is indeed zero (as it should since the above model assumes zero mass for the muon)
Here is a second where you can see the same:

> <event>
> 6 1 +6.0227000e+00 2.24253500e+02 7.54677100e-03 1.14412900e-01
> 5 -1 0 0 502 0 -0.0000000000e+00 +0.0000000000e+00 +2.0833089562e+02 2.0833089562e+02 0.0000000000e+00 0.0000e+00 -1.0000e+00
> 21 -1 0 0 501 502 +0.0000000000e+00 -0.0000000000e+00 -3.0177044867e+02 3.0177044867e+02 0.0000000000e+00 0.0000e+00 -1.0000e+00
> -24 2 1 2 0 0 -1.1408599174e+02 +8.5703191537e+01 +1.1904681322e+02 2.0116752224e+02 7.7042700609e+01 0.0000e+00 0.0000e+00
> 6 1 1 2 501 0 +1.1408599174e+02 -8.5703191537e+01 -2.1248636627e+02 3.0893382204e+02 1.7300000000e+02 0.0000e+00 -1.0000e+00
> 13 1 3 3 0 0 -1.1712570269e+02 +8.8067056032e+01 +1.2597195218e+02 1.9324380799e+02 0.0000000000e+00 0.0000e+00 -1.0000e+00
> -14 1 3 3 0 0 +3.0397109564e+00 -2.3638644948e+00 -6.9251389570e+00 7.9237142567e+00 0.0000000000e+00 0.0000e+00 1.0000e+00
> <mgrwt>

and a third (for the opposite sign w/top)

> <event>
> 6 2 +6.0227000e+00 2.21604600e+02 7.54677100e-03 1.14617400e-01
> -5 -1 0 0 0 501 -0.0000000000e+00 +0.0000000000e+00 +5.1067510685e+02 5.1067510685e+02 0.0000000000e+00 0.0000e+00 1.0000e+00
> 21 -1 0 0 501 502 +0.0000000000e+00 -0.0000000000e+00 -3.6806641612e+02 3.6806641612e+02 0.0000000000e+00 0.0000e+00 1.0000e+00
> 24 2 1 2 0 0 +1.0890952437e+02 -8.5547153041e+01 +4.6260557982e+02 4.8950302420e+02 8.0185337399e+01 0.0000e+00 0.0000e+00
> -6 1 1 2 0 502 -1.0890952437e+02 +8.5547153041e+01 -3.1999688909e+02 3.8923849877e+02 1.7300000000e+02 0.0000e+00 1.0000e+00
> -13 1 3 3 0 0 +7.0815643242e+01 -8.6273265120e+01 +2.5393021818e+02 2.7737787819e+02 0.0000000000e+00 0.0000e+00 1.0000e+00
> 14 1 3 3 0 0 +3.8093881133e+01 +7.2611207924e-01 +2.0867536164e+02 2.1212514602e+02 0.0000000000e+00 0.0000e+00 -1.0000e+00

So I can not reproduce your error.

One wild guess is that you are using a code of reshuffling restoring the muon mass (do you?) in that case, this might be what the problem is.

Cheers,

Olivier

> On 15 Jun 2018, at 02:32, Jazmine Jefferson <email address hidden> wrote:
>
> Question #670144 on MadGraph5_aMC@NLO changed:
> https://answers.launchpad.net/mg5amcnlo/+question/670144
>
> Status: Answered => Open
>
> Jazmine Jefferson is still having a problem:
> The LHEF shows the same issue, and then I simply use ExRootAnalysis to
> convert to the root file
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

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