FastJet  3.1.3
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1 Note on the implementation of the CMS Iterative Plugin
2 
3 The code is initially the CMSSW implementation in
4 CMSIterativeConeAlgorithm.cc in /CMSSW/RecoJets/JetAlgorithms
5 (more precisely, Revision 14 of the cc file)
6 
7 To avoid importing too many files from CMSSW, we did a couple of
8 modifications starting from the CMSIterativeConeAlgorithm file:
9 
10  - directly used the FastJet PseudoJet instead of the InputItem
11  present initially. Note that access to the info then has to be done
12  using . instead of -> which implies a few small modifications here
13  and there.
14 
15  - added a small piece of code to compute Et. That peice of code is
16  the same as tracked down in the CMS code. It comes from the Root
17  Lorentzvector, more precisely, the PxPyPzE4D implementation.
18 
19  - The ordering in Et, NumericSafeGreaterByEt, is imported from
20  EtComparator.h in PhysicsTools/Utilities/
21 
22  - The DeltaR2 computation is imported from DeltaR.cc and DeltaPhi.cc
23  in CMSSW/DataFormats/Math
24 
25  - finally, instead of the ProtoJet construction, we use the
26  ClusterSequence-compatible clustering. That one follows the line of
27  what is done in the SISCone plugin. Note that ve've checked in the
28  CMSSZ code that the protojet is indeed reconstructed using E-scheme
29  recombination (while the stability test is done using Et-scheme)
30 
31 Finally, we want to thank Andreas Oehler for pointing us to the CMS
32 code.