install mg5amc_py8_interface linking to local pythia installation

[Pablo Martin]

Hi Olivier,

I am doing some work with MG5 at NLO. I would like to know how to install the mg5amc_py8_interface and link it to a local pythia installation.

I can correctly set the pythia8_path in the mg5 configuration file, but the script compile.py in HEPTools/MG5aMC_PY8_interface assumes that Makefile.inc is in pythia8235/, but in my pythi installation is by default in pythia8/share/Pythia8/examples/. This problem has already been presented in this thread:

https://bugs.launchpad.net/mg5amcnlo/+bug/1674095

How should I modify the script to make it work? I want to run a NLO+PS with FxFx matching and merging and would like to be able to use this interface.

I am actually more interested in using the default pythia8 installation within madgraph5, but I already had some problems before due to a missing iostreams library, which I reported in this thread:

https://bugs.launchpad.net/mg5amcnlo/+bug/1779081

and Marco suggested to try an external pythia8 installation. I have tried to understand the problem in this last thread and I still don't know how could I solve the issue :S

Thanks!

Pablo

[Olivier Mattelaer (olivier-mattelaer)]

Hi Pablo,

The "mg5amc_py8_interface" is only needed for LO run not for NLO+PS
so this should not be an issue for you for the moment as far as I have understood what you want to do.

For the rest, I will assign this to Valentin which should be able to help you.

Cheers,

Olivier

> On 26 Sep 2018, at 16:54, Pablo Martin <email address hidden> wrote:
>
> Public bug reported:
>
> Hi Olivier,
>
> I am doing some work with MG5 at NLO. I would like to know how to
> install the mg5amc_py8_interface and link it to a local pythia
> installation.
>
> I can correctly set the pythia8_path in the mg5 configuration file, but
> the script compile.py in HEPTools/MG5aMC_PY8_interface assumes that
> Makefile.inc is in pythia8235/, but in my pythi installation is by
> default in pythia8/share/Pythia8/examples/. This problem has already
> been presented in this thread:
>
> https://bugs.launchpad.net/mg5amcnlo/+bug/1674095
>
> How should I modify the script to make it work? I want to run a NLO+PS
> with FxFx matching and merging and would like to be able to use this
> interface.
>
> I am actually more interested in using the default pythia8 installation
> within madgraph5, but I already had some problems before due to a
> missing iostreams library, which I reported in this thread:
>
> https://bugs.launchpad.net/mg5amcnlo/+bug/1779081
>
> and Marco suggested to try an external pythia8 installation. I have
> tried to understand the problem in this last thread and I still don't
> know how could I solve the issue :S
>
> Thanks!
>
> Pablo
>
> ** Affects: mg5amcnlo
> Importance: Undecided
> Status: New
>
> --
> You received this bug notification because you are subscribed to
> MadGraph5_aMC@NLO.
> https://bugs.launchpad.net/bugs/1794543
>
> Title:
> install mg5amc_py8_interface linking to local pythia installation
>
> Status in MadGraph5_aMC@NLO:
> New
>
> Bug description:
> Hi Olivier,
>
> I am doing some work with MG5 at NLO. I would like to know how to
> install the mg5amc_py8_interface and link it to a local pythia
> installation.
>
> I can correctly set the pythia8_path in the mg5 configuration file,
> but the script compile.py in HEPTools/MG5aMC_PY8_interface assumes
> that Makefile.inc is in pythia8235/, but in my pythi installation is
> by default in pythia8/share/Pythia8/examples/. This problem has
> already been presented in this thread:
>
> https://bugs.launchpad.net/mg5amcnlo/+bug/1674095
>
> How should I modify the script to make it work? I want to run a NLO+PS
> with FxFx matching and merging and would like to be able to use this
> interface.
>
> I am actually more interested in using the default pythia8
> installation within madgraph5, but I already had some problems before
> due to a missing iostreams library, which I reported in this thread:
>
> https://bugs.launchpad.net/mg5amcnlo/+bug/1779081
>
> and Marco suggested to try an external pythia8 installation. I have
> tried to understand the problem in this last thread and I still don't
> know how could I solve the issue :S
>
> Thanks!
>
> Pablo
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/mg5amcnlo/...

[Pablo Martin (pmartin7)]

Hi Olivier,

thanks for your reply. So just to make sure I understand it correctly, at NLO I only have to set the ickkw parameter in the run_card to its value and the corresponding Qcut and njetmax FxFx parameters in the shower_card. Is that right?

For LO+PS I will wait for Valentin's response. But one more question about this: how do I set this option in the run_card? I know that in older versions of MG5 there used to be an ickkw = 1 option in the run_card for the MLM scheme. How should I proceed now?

Thanks very much!

Pablo

[Pablo Martin (pmartin7)]

P.S: forget about the ickkw = 1 option in the run_card for the MLM scheme. I just realised this is only available when importing a LO model, but not when importing the corresponding NLO model and running at LO+PS

[Olivier Mattelaer (olivier-mattelaer)]

Hi,

> P.S: forget about the ickkw = 1 option in the run_card for the MLM
> scheme. I just realised this is only available when importing a LO
> model, but not when importing the corresponding NLO model and running at
> LO+PS

That's not true. You can run LO+PS and set up MLM (or CKKW-L) even if the model is NLO.
But in that case, your process should not request ANY NLO contribution.
i.e. you can do

import loop_sm
generate p p > t t~
add process p p > t t~ j
output
launch

In that case, ickkw is actually automatically set to one.

> at NLO I only have to set the ickkw parameter in the run_card to its
> value and the corresponding Qcut and njetmax FxFx parameters in the
> shower_card. Is that right?

Don't you have also to add the veto cut inside the parton-shower?

Cheers,

Olivier

> On 27 Sep 2018, at 11:11, Pablo Martin <email address hidden> wrote:
>
> P.S: forget about the ickkw = 1 option in the run_card for the MLM
> scheme. I just realised this is only available when importing a LO
> model, but not when importing the corresponding NLO model and running at
> LO+PS
>
> --
> You received this bug notification because you are subscribed to
> MadGraph5_aMC@NLO.
> https://bugs.launchpad.net/bugs/1794543
>
> Title:
> install mg5amc_py8_interface linking to local pythia installation
>
> Status in MadGraph5_aMC@NLO:
> New
>
> Bug description:
> Hi Olivier,
>
> I am doing some work with MG5 at NLO. I would like to know how to
> install the mg5amc_py8_interface and link it to a local pythia
> installation.
>
> I can correctly set the pythia8_path in the mg5 configuration file,
> but the script compile.py in HEPTools/MG5aMC_PY8_interface assumes
> that Makefile.inc is in pythia8235/, but in my pythi installation is
> by default in pythia8/share/Pythia8/examples/. This problem has
> already been presented in this thread:
>
> https://bugs.launchpad.net/mg5amcnlo/+bug/1674095
>
> How should I modify the script to make it work? I want to run a NLO+PS
> with FxFx matching and merging and would like to be able to use this
> interface.
>
> I am actually more interested in using the default pythia8
> installation within madgraph5, but I already had some problems before
> due to a missing iostreams library, which I reported in this thread:
>
> https://bugs.launchpad.net/mg5amcnlo/+bug/1779081
>
> and Marco suggested to try an external pythia8 installation. I have
> tried to understand the problem in this last thread and I still don't
> know how could I solve the issue :S
>
> Thanks!
>
> Pablo
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/mg5amcnlo/+bug/1794543/+subscriptions

[Pablo Martin (pmartin7)]

Hi Olivier,

Don't you have also to add the veto cut inside the parton-shower?
>

Yes, I forgot about that in my last comment. Thanks!

I will wait for Valentin's response about the NLO question.

Chers,

Pablo

El vie., 28 sept. 2018 a las 9:25, Olivier Mattelaer (<
<email address hidden>>) escribió:

> Hi,
>
> > P.S: forget about the ickkw = 1 option in the run_card for the MLM
> > scheme. I just realised this is only available when importing a LO
> > model, but not when importing the corresponding NLO model and running at
> > LO+PS
>
> That's not true. You can run LO+PS and set up MLM (or CKKW-L) even if the
> model is NLO.
> But in that case, your process should not request ANY NLO contribution.
> i.e. you can do
>
> import loop_sm
> generate p p > t t~
> add process p p > t t~ j
> output
> launch
>
> In that case, ickkw is actually automatically set to one.
>
> > at NLO I only have to set the ickkw parameter in the run_card to its
> > value and the corresponding Qcut and njetmax FxFx parameters in the
> > shower_card. Is that right?
>
>
> Don't you have also to add the veto cut inside the parton-shower?
>
> Cheers,
>
> Olivier
>
>
> > On 27 Sep 2018, at 11:11, Pablo Martin <email address hidden>
> wrote:
> >
> > P.S: forget about the ickkw = 1 option in the run_card for the MLM
> > scheme. I just realised this is only available when importing a LO
> > model, but not when importing the corresponding NLO model and running at
> > LO+PS
> >
> > --
> > You received this bug notification because you are subscribed to
> > MadGraph5_aMC@NLO.
> > https://bugs.launchpad.net/bugs/1794543
> >
> > Title:
> > install mg5amc_py8_interface linking to local pythia installation
> >
> > Status in MadGraph5_aMC@NLO:
> > New
> >
> > Bug description:
> > Hi Olivier,
> >
> > I am doing some work with MG5 at NLO. I would like to know how to
> > install the mg5amc_py8_interface and link it to a local pythia
> > installation.
> >
> > I can correctly set the pythia8_path in the mg5 configuration file,
> > but the script compile.py in HEPTools/MG5aMC_PY8_interface assumes
> > that Makefile.inc is in pythia8235/, but in my pythi installation is
> > by default in pythia8/share/Pythia8/examples/. This problem has
> > already been presented in this thread:
> >
> > https://bugs.launchpad.net/mg5amcnlo/+bug/1674095
> >
> > How should I modify the script to make it work? I want to run a NLO+PS
> > with FxFx matching and merging and would like to be able to use this
> > interface.
> >
> > I am actually more interested in using the default pythia8
> > installation within madgraph5, but I already had some problems before
> > due to a missing iostreams library, which I reported in this thread:
> >
> > https://bugs.launchpad.net/mg5amcnlo/+bug/1779081
> >
> > and Marco suggested to try an external pythia8 installation. I have
> > tried to understand the problem in this last thread and I still don't
> > know how could I solve the issue :S
> >
> > Thanks!
> >
> > Pablo
> >
> > To manage notifications about this bug go to:
> > https://bugs.launchpad.net/mg5amcnlo/+bug/1794543/+subscriptions
>
> --
> You received this bug notification because...