WWANA: A DELPHI WW Analysis Package


A standard package for W analyses

Version 6.00

For a full description of WWANA you can have a look at the WWANA delphi note.
For an update of settings and inputs to WWANA version 6.00 and a detailed description of its new ntuple structure please read the documentation in wwana afs public area (see the location of the code) or in the following postscript format.
Here you will find a flow chart of the program.

WWANA Authors


WWANA is intended as a standard DELPHI package for use in WW physics analysis: it provides information relevant to both W mass measurements and TGC studies. The program is written in PATCHY format (click here for reference manual ) and uses the SKELANA package to fill the common blocks which contain the information from the DST. The main output of the package is a column wise ntuple organised in blocks of relevance to particular W decay channels and of more general event information. By setting logical parameters, the user can choose which blocks of information to include in the ntuple. This choice will depend on which analysis and which W decay channels the user is interested in studying. All the variables and the physical quantities that have been evaluated are stored in common blocks; these have the same structure as the ntuple blocks.

Location of the code

The WWANA program is composed of several PAM files, which are located in the common area for DELPHI LEP200 physics on afs machines: /afs/cern.ch/delphi/tasks/lep200/wphysics/wwana The core of the program is composed of two PAM files: Two versions of the main program are stored in this area: a stable version wwanaxx.car, wwcdexx.car updated every few weeks, and a development version wwana.car_vyyy, wwcde.car_vyyy updated as soon as changes are suggested. WWANA also uses the following files: A further two files are provided in this area to assist the WWANA user:

How to use WWANA

WWANA works in SKELANA framework. To be appended to SKELANA the user has to include:
WWANA handles the flags for the filling of the SKELANA common blocks in the WWINI subroutine, where they should be set to the desired values. The SKELANA LVLOCK array is used inside WWANA for track selection; WWANA re-orders the VECP array so that the locked tracks are at the end. The users can perform their own track selection within SKELANA or use the W team track selection within WWANA by switching the corresponding logical word in the file wwcde.car.
The user can set general cuts to be used inside WWANA for the tagging of the different WW decay channels. These cuts are defined inside +KEEP,WWCUTS. in wwcde.car and are set by default to very loose values in order to maximize the tagging efficiency, thus leaving complete control to the user. The full list of the cuts is reported in the documentation (at the beginning of the page).
The user can also set a certain number of parameters which control the logic of the analysis. They are related to the options for the constrained fit, the lepton identification and the jet clustering algorithm to be used. The full list of the parameters with their default and allowed values is reported in the documentation.
A Column-Wise Ntuple is used to store all the event information: this choice allows the use of a block structure for the ntuple. The user can therefore decide which of the blocks they want to include in their ntuple in order to meet the individual needs of their analysis. The ntuple output file ww.ntp is generated automatically when running the program.

Ntuple blocks

The optional blocks of the ntuple and their contents are described below. Only the TITLE block, the HEADER block and the EVENT block are always filled, while the other blocks can be excluded (or included) by changing the corresponding logical word in wwcde.car.

R. C. : (Send me an e-mail)