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The inclusive mode

The algorithm proceeds as follows:
  1. For every final state object1 $h_k$ and for every pair $h_k$ and $h_l$, compute the resolution variables $d_{kB}$ and $d_{kl}$. The precise definition of these variables can be chosen by the user (using the parameter angle), and will be described in detail in section 2.4. They always have the property that in the small angle limit they reduce respectively to the squared relative transverse momentum of the object with respect to the beam direction, and the squared relative transverse momentum of one object with respect to the other.
    $\displaystyle d_{kB}$ $\textstyle \simeq$ $\displaystyle E_k^2 \theta_{kB}^2$ (1)
      $\textstyle \simeq$ $\displaystyle k_{\perp kB}^2, {\rm for~} \theta \rightarrow 0$  
    $\displaystyle d_{kl}$ $\textstyle \simeq$ $\displaystyle {\rm min}(E_k^2,E_l^2)\theta_{kl}^2$ (2)
      $\textstyle \simeq$ $\displaystyle k_{\perp kl}^2, {\rm for~} \theta_{kl} \rightarrow 0$  

    At this stage, a dimensionless parameter $R$ is introduced[3], which plays a radius-like role in defining the extent of the jets. This is usually set to 1.0.
  2. Scale the $d_{kB}$ by $R^2$
    \begin{displaymath}
d_k = d_{kB} R^2
\end{displaymath} (3)

  3. Find the smallest value among the $d_k$ and $d_{kl}$. If a $d_{kl}$ is the smallest, $h_k$ and $h_l$ are combined into a single object with momentum $p_{(kl)}$ according to a user specified recombination scheme (parameter recom) which will be described in section 2.5. As an example, recom = 1 would correspond to 4-vector addition. If a $d_k$ is the smallest, object $k$ is defined to be a jet and is removed from the list of objects to be merged.
  4. Repeat until all objects have been included in jets.

next up previous
Next: The exclusive mode Up: The algorithm Previous: The algorithm
Jonathan Couchman 2002-10-02