[Rivet] Z projection on Rivet

[Gavin Hesketh]

Hi Frank,


Frank Siegert wrote:
> Hi all,
> 
> On 01/02/11 12:01, Frank Siegert wrote:
>>> 2) for D0 Z->mm, don't add the photons; for ATLAS Z->mm and all Z->ee,
>>> add the photons. I'm sure there is an easy way to code a switch here.
>>> Note that for the D0 Z->mm, still need to select the photons in a 0.2
>>> cone and exclude them from the jet finder.
>>
>> Ok, I'm starting to wonder whether we should put all of this into the
>> ZFinder projection or give up having a uniform ZFinder and do all of
>> this stuff "manually" in the analyses. Opinions?
>>
>>> The current analyses
>>> (D0_2009_S8349509.cc, D0_2008_S7863608.cc) instead apply a cut on
>>> jet-muon overlap, which which was not done in the data analysis.
>>
>> Right, thanks. That's my mistake, I didn't see the clear specification
>> of particle-level cuts which don't contain the overlap cut anymore. It's
>> good to have the author of these analyses checking them thoroughly :)
> 
> These two issues are fixed now in
> http://projects.hepforge.org/rivet/trac/changeset/2918
> 
>  >> 1) calculate the mass after adding the photons, if the photons are
>  >> going to be added (probably a tiny effect)
> 
> What about the pT and eta cuts, also after photons are added or before?


After. If the photons are going to be added, they should be added to the 
nearest electron before any cuts are applied; it's equivalent to cutting 
on calorimeter-based objects.

cheers,
	Gsvin



> Cheers,
> Frank
> 
> PS: When this is finished, I'll have to re-validate the ZFinder and 
> related analyses.