[Rivet] submission of analysis ATLAS_2014_I1282447

[Kristin Lohwasser]

Hi,

To be more specific, the disabling FSR is concerning QED only and it is to
get born level electrons. I agree it is unfortunate,it was not my decision
and should be changed for the next round of w+c analysis.

I tried to tune the selection such that it is very close to born,it should
be 1-2% accurate judging from 10000 events cutflow comparing the born level
to the rivet code.

Best
Kristin
 Am 23.11.2014 18:56 schrieb "Andy Buckley" <andy.buckley at cern.ch>:

> Hi Kristin,
>
> Thanks! I've copied in Roman L as the current ATLAS Rivet contact, and
> James & Monica since I don't know if the system has changed at all with
> the shift to the new PMG group.
>
> Just to clarify, when you say "FSR must be turned off", do you mean that
> *QED* FSR must be turned off? That should have less impact than
> disabling QCD FSR, which I really hope isn't what you meant, but is
> still a bit against the Rivet ethos.
>
> Assuming that you do mean QED FSR, I thought that all ATLAS SM EW
> results were now meant to use dressed leptons, plus Born ones if
> necessary -- in existing EW measurements such as the Z pT and phi*
> observables, and even the Z underlying event, we only implemented the
> dressed version in Rivet because there isn't any portable definition of
> Born leptons. Requiring that no QED FSR is enabled is one way to force a
> portable Born definition, but a) it means this analysis can't be used in
> the same MC run as other 7 TeV pp W analyses, and b) I guess that matrix
> elements containing higher-order QED corrections are also not usable
> with this analysis, since the _ME_ is then providing the sort of QED
> correction that you're labelling as "FSR", and there really is no "Born"
> W to compare to?
>
> If all this is unavoidable, then we just deal with it and of course any
> analysis code is better than none, but since the MC/theory technology is
> ever-improving if this analysis can be made more future proof using the
> existing data then now is the time to do so.
>
> Thanks again,
> Andy
>
>
>
> On 22/11/14 23:37, Kristin Lohwasser wrote:
> > Dear all,
> >
> > herewith I would like to submit ATLAS analysis ATLAS_2014_I1282447
> > (W+charm production)
> >
> > Two things to note:
> > -- some part of the measurements are ratios (also to Winclusive
> > production), this is a bit harder to implement and not possible in one
> > go, therefore I have put a description at the start of the .cc file
> > (thinking about it, also the W+/W- histograms probably will work only
> > for post-processing in the case of generators only producing one
> > charge). [however the most interesting plots can ge gotten out straigh
> > away]
> > -- THE CODE SHOULD BE RUN WITH FSR TURNED OFF!!!
> >
> > It has been tested with the ATLAS version of Rivet 2.x.
> >
> > Please let me know, once this is uploaded to your website.
> >
> > Best
> > Kristin
> >
> >
> >
> > _______________________________________________
> > Rivet mailing list
> > Rivet at projects.hepforge.org
> > https://www.hepforge.org/lists/listinfo/rivet
> >
>
>
> --
> Dr Andy Buckley, Royal Society University Research Fellow
> Particle Physics Expt Group, University of Glasgow / PH Dept, CERN
>
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