Expected limt

Roofit and RooStats
#1

hello ROOT team

now I try to draw Xsection with expected limit like this http://inspirehep.net/record/901200/files/fig20.png

my data signals are

mass Xsection
500 .30430E-06
1000 .43762E-07
1500 .10090E-07
2000 .29253E-08
2500 .95735E-09
3000 .33629E-09

and backgrounds are .45655E-03
.24545E-02

assumed luminosity is 10 fb^-1

I studied some roostat examples but could not understand.

so if you know any solution or information, could you help me?

-nam

#2

Hi,

Which limit would you like to compute ? CLs ? You could use for example the asymptotic formulae to compute it. In RooStats you can do it with the AsymptoticCalculator (using from example the StandardHypoTestInvDemo.C macro).
In order to use it you need to build a workspace, with your model, which I presume, is a simple number counting model, i.e. a Poissson(nobs | nexp).
You can see some examples in the RooStats tutorials,
twiki.cern.ch/twiki/bin/view/Ro … isson_Coun

Best Regards

Lorenzo