Parton-Shower error in e+e- collision

Asked by Jian Zhang

Hi,

I generate e- e+ > t t~ , ( t > b w+ , w+ > j j ) , ( t~ > b~ w- , w- > j j ) with MG5_aMC_v3_3_2. Operation steps are as follows

generate e- e+ > t t~ , ( t > b w+ , w+ > j j ) , ( t~ > b~ w- , w- > j j )
output smee
launch
1
2
0
set lpp1 +3
set lpp2 -3
set pdlabel1 clic3000ll
set pdlabel2 clic3000ll
set ebeam 1500
/home/usr/MG5_aMC_v3_3_2/Delphes/cards/delphes_card_CLICdet_Stage3_fcal.tcl

and then I get "ERROR: Parton-Shower are not yet ready for such proton component definition. Parton-shower will be switched off"

What's the problem?

Thanks
Cheers

Jian

Question information

Language:
English Edit question
Status:
Answered
For:
MadGraph5_aMC@NLO Edit question
Assignee:
No assignee Edit question
Last query:
Last reply:
Revision history for this message
Olivier Mattelaer (olivier-mattelaer) said :
#1

Hi,

I think that the issue is double here:
1) we use a convoluted PDF for beamstrahlung and ISR, those effect should be handle differently by the parton-shower.
and therefore the parton-shower lack information to disantengle them
2) the second issue is the the lhe format has not convention to provide such imformation in a consistent way.

Now if you turn off all QED parton-shower/initial state parton shower and are only interested in the FS/QCD radiation,
then you should be able to run pythia.
Now for that you need to tweak the input file for pythia
(and therefore likely run pythia by hand, running pythia via the ./bin/madevent might also work actually but then you need to edit the pythia8_card.dat to configure pythia8 as you want --i.e. do not blindly trust/use the default configuration).

Cheers,

Olivier

> On 9 May 2022, at 16:05, Jian Zhang <email address hidden> wrote:
>
> New question #701726 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/701726
>
> Hi,
>
> I generate e- e+ > t t~ , ( t > b w+ , w+ > j j ) , ( t~ > b~ w- , w- > j j ) with MG5_aMC_v3_3_2. Operation steps are as follows
>
> generate e- e+ > t t~ , ( t > b w+ , w+ > j j ) , ( t~ > b~ w- , w- > j j )
> output smee
> launch
> 1
> 2
> 0
> set lpp1 +3
> set lpp2 -3
> set pdlabel1 clic3000ll
> set pdlabel2 clic3000ll
> set ebeam 1500
> /home/usr/MG5_aMC_v3_3_2/Delphes/cards/delphes_card_CLICdet_Stage3_fcal.tcl
>
>
> and then I get "ERROR: Parton-Shower are not yet ready for such proton component definition. Parton-shower will be switched off"
>
> What's the problem?
>
> Thanks
> Cheers
>
> Jian
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Can you help with this problem?

Provide an answer of your own, or ask Jian Zhang for more information if necessary.

To post a message you must log in.