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Subsections

Broadening with respect to the photon axis (normalized to E)


Definition of the observable

We consider here the jet broadening with respect to the photon axis measured in the currect hemisphere of the Breit frame defined as

$\displaystyle B_{zE} =\frac{\sum_{i \in {\cal H}_{\mathrm{C}}}\vert\vec{p}_i \times \vec{n}\vert} {2 \sum_{i \in {\cal H}_{\mathrm{C}}}\vert\vec{p}_i\vert}\>.$ (6)

where the unit vector $ \vec{n}$ refers to the direction of the photon axis in the Breit frame and $ {\cal H_{\mathrm{C}}}$ denotes the current hemisphere. This observable has been resummed in [2].

Born event used for the analysis

The hard scale (Q) is taken to be photon virtuality.

Elementary tests on the observable

Test result
check number of jets T
all legs positive T
globalness T

Single emission properties

leg $ \ell$ $ a_{\ell}$ $ b_{\ell}$ $ g_{\ell}(\phi)$ $ d_{\ell}$ $ \langle \ln g_{\ell}(\phi) \rangle$
1 1.000 $ 0.000$ 1 1.000 0
2 1.000 $ 0.000$ 1 2.000 0

Multiple emission tests

Test result
continuously global T
exponentiation (condition 1) T
exponentiation (condition 2a) T
exponentiation (condition 2b) T
exponentiation T
additivity F
eliminate subleading effects T
opt. probe region exists T

Information regarding the presence of possible zeros

leg 1 2
1 good zero no zero
2 no zero no zero

Classification of legs into divergent sequences with shared properties

Sequence number 1 has 1 legs
Legs in the sequence: 1
Orientation of the legs: 1
Type of zero: zt_sumvecpt
Position of the divergence: $ \sum_{i \in seq.} R_i = 2.000$

Multiple emission effects

Second order coefficient $ {\cal F}_2$ of the function $ {\cal F}$

Number of events used: 1000000

Result for each colour configuration
  $ {\cal F}_2 =-0.26740\pm 0.00179$

For a precise definition of the configurations see [6].

The multiple emission function $ {\cal F}$

Number of events used: 1000000
\begin{figure}\centering \epsfig{file=../OutputAnalysis/brd_zE.ff.eps, width=.7\textwidth, angle=0} \end{figure}

Collection of automatically generated results

brd_zE.tar.gz collects all files produced automatically by Caesar.
next up previous
Next: Mass (normalized to E) Up: Observables in DIS Previous: Thrust with respect to
Giulia Zanderighi 2004-11-19