multijet analysis

[roberto ruiz]

Dear Developers,

I have been trying to validate the "0 leptons + 2-6 jets + Etmiss" analysis of
ATLAS for SUSY searches using the msugra model as reference. The point is that for large m0's or m12's

or in other words heavy squarks/gluinos, the efficiencies are not well reproduced for most of the signal regions defined by the collaboration analysis. I'm using delphes 3.0.5 for the task.
I would like to know whether is possible to tune some of the parameters defined in the ATLAS card to improve this.

Best Regards,
Roberto

[Alexandre Mertens]

Hello Roberto,

Thanks for using Delphes3.

Each analysis is using different algorithms and then different efficiencies. Therefore the card provided is a realistic example that can be tuned by the user. But it cannot be used to reproduce any analysis out of the box.

We are currently working on an improved ATLAS card.

In your particular example, in which variable do you see a discrepancy?

by the way, Delphes is evolving a lot thanks to user comments, so don't hesitate to update your version to the current one (3.0.9).

cheers,

Alexandre

[Alexandre Mertens]

Hello,

It is not easy to link these results with what has to be changed in the Card. I just had a look to the paper you mentioned and they are using anti-kt jet clustering algorithm with a radius parameter of 0.4.

Did you already modified this value?

Also in the version 3.0.10, we will add a module to correct for the Jet Energy Scale which might be important in your case.

cheers,

Alexandre