
   Request for a DESY Summer Student in 2012
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   Name :   Dr. Pavel Starovoitov       email :      Pavel.Starovoitov@desy.de
  
   Tel  :  5380                    Room :   03/042
 
   DESY-Group/Experiment :  ATLAS

 
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   Short description of the project the student should work on  :

ATLAS collaboration publishes all the jet measurements with two jet size parameters (R=0.4 and R=0.6). The jet energy scale (JES) uncertainty is the main source 
of systematic uncertainty on the published cross sections. In the recent ATLAS publications the JES uncertainty 
in each rapidity bin was divided into 13 components, each is 100% correlated across transverse momentum bins separately for each jet size. 
In order  to simultaneously include both the jet sizes in the NLO QCD interpretation one need to know the correlations of the components of 
JES uncertainty between different jet sizes. 
The main goal of the project would be to study  an amount of energy shared by jets with R=0.6 
and R=0.4 and to evaluate the correlations of each component of JES uncertainty between different jet sizes. 
The obtained JES correlation will be used for the simultaneous determination of strong coupling from the measured 
inclusive jet spectrum with two different jet radii. This should reduce the largest systematic uncertainty.


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   Physics / Computing/ Engineering  Content of the project :

      50%/50%/0%
      
   During his/her stay the summer student will acquaint with next-to-leading order MC generators and real data analysis. 
   The student will deepen his/her understanding of the Standard Model of particle physics, especially of perturbative QCD. 
   He/She will study the dependence of the single inclusive jet cross section on the jet radius as 
   well as on the choice of the parton density functions set.  The student will investigate the difference in jet properties arising 
   from the different jet sizes and evaluate the correlation of the JES uncertainties between different jet radii. 
   He/she will propagate this correlation to the final uncertainty on the determination of strong coupling from jet spectrum.
   
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  Special Qualifications expected from the student ( Computing,...) :
 
          C/C++,ROOT,Statistics would be helpful

 
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  Other remarks :  



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   Supervisor(s) during the project (17/07/12 - 6/09/12) :
 
  
   Name:   Dr. Pavel Starovoitov           Tel:   5380    email : Pavel.Starovoitov@desy.de
