Method to exclude duplicated processes

Asked by Sihyun Jeon

Dear Olivier,

I am trying to make WW NLO samples with same flavor lepton decays but wonder if what I am doing would make sense.

So I am doing like below
generate p p > e+ ve w- [QCD] -> [1]
add process p p > e- ve~ w+ [QCD] -> [2]

and in MadSpin
decay w- > e- ve~ -> [3]
decay w+ > e+ ve -> [4]

But this would be problematic when the "e+ ve" from [1] is from onshell W+ since it will give you duplicated contributions from [2] + [4]. Is my guess correct?

[1] + [3] will give you :
(1) onshell w+ & onshell w-
(2) offshell w+ & onshell w-

[2] + [4] will give you :
(3) onshell w+ & onshell w-
(4) onshell w+ & offshell w-

Due to (1) and (3), there is some double countings -> This is my understanding

If my understanding is correct I wonder if this would avoid the double counting issues
generate p p > e+ ve w- $$ w+ [QCD] -> [1]
add process p p > e- ve~ w+ [QCD] -> [2]

and in MadSpin
decay w- > e- ve~ -> [3]
decay w+ > e+ ve -> [4]

Then I expect that [1] would not allow onshell w+ production and thus give you
[1] + [3]
(1) offshell w+ & onshell w-

[2] + [4]
(2) onshell w+ & onshell w-
(3) onshell w+ & offshell w-

Would this be a correct way to remove duplicated onshell w+ and onshell w- contributions?

Regards,
Sihyun.

Question information

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

Hi,

The answer is not trivial, the issue with the $$ syntax is that you might break gauge invariance of the theory.
I do not know if this is the case for this process.
You can do
check p p > e+ ve w- $$ w+, w- > e- ve~
and
check p p > e+ ve w- j $$ w+, w- > e- ve~

to check that.

Independently of that,
I would suggest to simply do
generate p p > e+ ve e- ve~ [QCD]

Cheers,

Olivier

> On 7 Oct 2021, at 14:45, Sihyun Jeon <email address hidden> wrote:
>
> New question #698999 on MadGraph5_aMC@NLO:
> https://answers.launchpad.net/mg5amcnlo/+question/698999
>
> Dear Olivier,
>
> I am trying to make WW NLO samples with same flavor lepton decays but wonder if what I am doing would make sense.
>
> So I am doing like below
> generate p p > e+ ve w- [QCD] -> [1]
> add process p p > e- ve~ w+ [QCD] -> [2]
>
> and in MadSpin
> decay w- > e- ve~ -> [3]
> decay w+ > e+ ve -> [4]
>
> But this would be problematic when the "e+ ve" from [1] is from onshell W+ since it will give you duplicated contributions from [2] + [4]. Is my guess correct?
>
> [1] + [3] will give you :
> (1) onshell w+ & onshell w-
> (2) offshell w+ & onshell w-
>
> [2] + [4] will give you :
> (3) onshell w+ & onshell w-
> (4) onshell w+ & offshell w-
>
> Due to (1) and (3), there is some double countings -> This is my understanding
>
>
> If my understanding is correct I wonder if this would avoid the double counting issues
> generate p p > e+ ve w- $$ w+ [QCD] -> [1]
> add process p p > e- ve~ w+ [QCD] -> [2]
>
> and in MadSpin
> decay w- > e- ve~ -> [3]
> decay w+ > e+ ve -> [4]
>
> Then I expect that [1] would not allow onshell w+ production and thus give you
> [1] + [3]
> (1) offshell w+ & onshell w-
>
> [2] + [4]
> (2) onshell w+ & onshell w-
> (3) onshell w+ & offshell w-
>
>
> Would this be a correct way to remove duplicated onshell w+ and onshell w- contributions?
>
> Regards,
> Sihyun.
>
> --
> You received this question notification because you are an answer
> contact for MadGraph5_aMC@NLO.

Revision history for this message
Sihyun Jeon (shjeon) said :
#2

Thanks Olivier Mattelaer, that solved my question.

Revision history for this message
Arlen Roper (tfenimoreson2) said :
#3

In the context of a list of items, the process of creating copies of something can be called duplication, but is there a single word for the process of removing duplicates to create a list of unique items?

I'm open to any other ways of expressing this eg:

(Adjective + list) - expressing the state of the list before and after removing duplicates. (for the after state, I feel like I could use unique list, but what would I call it in the before-removal-of-duplicates stage?)

Note that I'm not talking about duplication of the entire list i.e. "duplicated list", I'm talking about a list that has duplicated elements that should be removed

https://www.hairstylenext.com

According to ODO, there is a predictable answer:

    deduplicate [verb] [with object]

    Eliminate duplicate or redundant information from (something, especially computer data)

    ‘they can deduplicate files uploaded by many different users to keep costs lower than otherwise possible’

A Google Ngram shows that it is used (if not all that often). Apparently in bursts, though it's possible that most of the examples in the earlier tranches (if not all) are typos and the like.

Revision history for this message
Joseph Kramer (jchadwickson2) said :
#4

In the context of a list of items, the process of creating copies of something can be called duplication, but is there a single word for the process of removing duplicates to create a list of unique items? https://exams.com.pk/

I'm open to any other ways of expressing this eg:

(Adjective + list) - expressing the state of the list before and after removing duplicates. (for the after state, I feel like I could use unique list, but what would I call it in the before-removal-of-duplicates stage?)

Note that I'm not talking about duplication of the entire list i.e. "duplicated list", I'm talking about a list that has duplicated elements that should be removed
Sometimes duplicate data is useful, sometimes it just makes it harder to understand your data. Use conditional formatting to find and highlight duplicate data. That way you can review the duplicates and decide if you want to remove them.
Select the range of cells that has duplicate values you want to remove. Tip:
Remove any outlines or subtotals from your data before trying to remove duplicates. Click Data > Remove Duplicates, and then Under Columns, check or uncheck the columns where you want to remove the duplicates.