[Rivet] how to use W/ZFinders for WZ analysis

[Roman Lysak]

  Hi Frank,

thanks for all your help.
Using Rivet 1.8.1 seem to improve things.

Thanks again,
   Roman

On 09/20/2012 07:50 PM, Frank Siegert wrote:
> Hi Roman,
>
> Actually, I think you almost gave the answer yourself: You want to use
> Rivet 1.8.x, since that contains a bug fix for W/ZFinder not dealing
> correctly with the input final state argument:
>
> http://rivet.hepforge.org/trac/changeset/3519
>
> Let us know whether that has fixed your problem.
>
> Cheers,
> Frank
>
> On 20 September 2012 18:03, Roman Lysak <lysak at fzu.cz> wrote:
>>    Dear Rivet authors,
>>
>> I'm trying to run Rivet analysis which selects one W and one Z boson which
>> both decay to electrons or muons (see the attachment).
>> In the analysis, I try to use W(Z)Finder projection.
>>
>> There is one problem when having events where both W and Z decay to leptons
>> of the same flavor (e.g. three electrons in final state): W and ZFinder can
>> use the same leptons to find W/Z boson.
>> Therefore, we apply the condition on W/Z leptons that they are not the same
>> (see lines 95-102). However, this is not ideal thing to do, since there
>> could be some events we are loosing with such condition (other leptons could
>> form W bosons too).
>>
>> I tried to use VetoedFinalState::addVetoOnThisFinalState() (see lines 40-50)
>> in order to restrict the particles WFinder can use (ZFinder uses all of the
>> particles).
>> However, this seem to have no effect and I still get the same numbers
>> (cross-section) as before when I did not apply this veto.
>> Actually, the cross-sections are quite different depending whether we use
>> (or not)  our condition on leptons from W/Z not being the same (about 50%
>> difference).
>>
>> Could you suggest what would be the best procedure to use to solve this?
>>
>> Thanks a lot,
>>    Roman Lysak
>>
>> P.S. I'm using Rivet 1.7.0, but as far as I understand there is the same
>> functionality for W/ZFinder in Rivet 1.8.0 just with a little bit different
>> syntax.
>>
>>
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