Single Event yields different PT

Asked by Joakim Flinckman on 2018-05-03

Hi!

I was getting weird results from a PT plot in MA5. So I tried to plot one single event to compare the result from doing the calculation by hand (with 4-momentum in LHE file). However MA5 didn't want to plot 1 single event. So i copied the 1 event 21 times in the LHE and ran MA5 again, this resulted in multiple spread bins in the histogram, like 50 GeV, 400 GeV and so on! The real value is ~25 GeV so something is clearly fishy here.

I generated the event ( g g > t1 t1~ , (t1 > t n1 , t > l+ vl b) , (t1~ > t~ n1 , t~ > l- vl~ b~) ) from the standard MSSM model in MG5.
Ran MA5 manually (./bin/ma5) and:
import single_event.lhe
plot PT(invisible)
submit single_analysis
open

What might cause this craziness? Im I doing something wrong?
Thanks!
/Joakim

Question information

Language:
English Edit question
Status:
Solved
For:
MadAnalysis 5 Edit question
Assignee:
No assignee Edit question
Solved by:
Benjamin Fuks
Solved:
2018-05-05
Last query:
2018-05-05
Last reply:
2018-05-04
Best Benjamin Fuks (fuks) said : #1

Hi Joakim,

The two commands
  plot PT(invisible)
and
  plot MET
are not equivalent. With the first one, one plots the pt of each invisible particle in the event. This means that one will have more than one entry per event. And of course this is not the MET spectrum which is what you are interested in.

I hope this clarifies.

Regards,

Benjamin

> On 3 May 2018, at 15:42 , Joakim Flinckman <email address hidden> wrote:
>
> New question #668551 on MadAnalysis 5:
> https://answers.launchpad.net/madanalysis5/+question/668551
>
> Hi!
>
> I was getting weird results from a PT plot in MA5. So I tried to plot one single event to compare the result from doing the calculation by hand (with 4-momentum in LHE file). However MA5 didn't want to plot 1 single event. So i copied the 1 event 21 times in the LHE and ran MA5 again, this resulted in multiple spread bins in the histogram, like 50 GeV, 400 GeV and so on! The real value is ~25 GeV so something is clearly fishy here.
>
> I generated the event ( g g > t1 t1~ , (t1 > t n1 , t > l+ vl b) , (t1~ > t~ n1 , t~ > l- vl~ b~) ) from the standard MSSM model in MG5.
> Ran MA5 manually (./bin/ma5) and:
> import single_event.lhe
> plot PT(invisible)
> submit single_analysis
> open
>
> What might cause this craziness? Im I doing something wrong?
> Thanks!
> /Joakim
>
>
>
> --
> You received this question notification because you are an answer
> contact for MadAnalysis 5.
>

Joakim Flinckman (jofl90) said : #2

Thanks Benjamin Fuks, that solved my question.