update beam polarisation

Asked by Karla Tame on 2018-11-22

Hello,

I have the newest MadGraph5 version (2.6.4) and I am trying to edit the
beam polarization in the run card, however, in this version is not
as easy as in the old one, now this option appears as:

#*********************************************************************
# Collider type and energy *
# lpp: 0=No PDF, 1=proton, -1=antiproton, 2=photon from proton, *
# 3=photon from electron *
#*********************************************************************
     0 = lpp1 ! beam 1 type
     1 = lpp2 ! beam 2 type
     60.0 = ebeam1 ! beam 1 total energy in GeV
     7000.0 = ebeam2 ! beam 2 total energy in GeV
# To see polarised beam options: type "update beam_pol"
#*********************************************************************

However I have tried to type in the run card and before launching
but nothing happens. Where should I type "update beam_pol"
and how can I do it?

Thank you very much!!

Cheers,
Karla.

Question information

Language:
English Edit question
Status:
Solved
For:
MadGraph5_aMC@NLO Edit question
Assignee:
No assignee Edit question
Solved by:
Karla Tame
Solved:
2018-11-23
Last query:
2018-11-23
Last reply:
2018-11-22

When you see this:(or something very similar since it depends of what you ask to run)

Do you want to edit a card (press enter to bypass editing)?
> /------------------------------------------------------------\
> | 1. param : param_card.dat |
> | 2. run : run_card.dat |
> | 3. madanalysis5_parton : madanalysis5_parton_card.dat |
> \------------------------------------------------------------/
> you can also
> - enter the path to a valid card or banner.
> - use the 'set' command to modify a parameter directly.
> The set option works only for param_card and run_card.
> Type 'help set' for more information on this command.
> - call an external program (ASperGE/MadWidth/...).
> Type 'help' for the list of available command
> [0, done, 1, param, 2, run, 3, madanalysis5_parton, enter path][90s to answer]

Now this is only going to add the following line inside the run_card:

> #*********************************************************************
> # Beam polarization from -100 (left-handed) to 100 (right-handed) *
> #*********************************************************************
> 0.0 = polbeam1 ! beam polarization for beam 1
> 0.0 = polbeam2 ! beam polarization for beam 2

If you edit your run_card outside of the MG5_aMC question related to the card edition (via a text editor for example) you are fully free to add those lines (the commented line and the content after the "!" are not needed in anyway) to use that functionality.

Cheers,

Olivier

PS: The same is true for any other "semi-hidden" block of the run_card
PPS: This is also true for FULLY hidden parameter of the run_card (those that do not have dedicated update function associated to them except the "update to_full"

> On 22 Nov 2018, at 19:27, Karla Tame <email address hidden> wrote:
>
> New question #676308 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/676308
>
>
> Hello,
>
> I have the newest MadGraph5 version (2.6.4) and I am trying to edit the
> beam polarization in the run card, however, in this version is not
> as easy as in the old one, now this option appears as:
>
> #*********************************************************************
> # Collider type and energy *
> # lpp: 0=No PDF, 1=proton, -1=antiproton, 2=photon from proton, *
> # 3=photon from electron *
> #*********************************************************************
> 0 = lpp1 ! beam 1 type
> 1 = lpp2 ! beam 2 type
> 60.0 = ebeam1 ! beam 1 total energy in GeV
> 7000.0 = ebeam2 ! beam 2 total energy in GeV
> # To see polarised beam options: type "update beam_pol"
> #*********************************************************************
>
> However I have tried to type in the run card and before launching
> but nothing happens. Where should I type "update beam_pol"
> and how can I do it?
>
> Thank you very much!!
>
> Cheers,
> Karla.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Karla Tame (karla15) said : #2

Dear Oliver,

Thank you very much!! I will do that.