Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Handy Tool for History Keeping of Geant4 Tracks -- J4HistoryKeeper --   The Particle Flow Analysis (PFA) is currently under intense studies as the
most promising way to achieve precision jet energy measurements required at the
future linear $e^+e^-$ collider. In order to optimize detector configurations
and to tune up the PFA it is crucial to identify factors that limit the PFA
performance and clarify the fundamental limits on the jet energy resolution
that remain even with the perfect PFA and an infinitely granular calorimeter.
This necessitates a tool to connect each calorimeter hit in particle showers to
its parent charged track, if any, and eventually all the way back to its
corresponding primary particle, while identifying possible interactions and
decays along the way. In order to realize this with a realistic memory space,
we have developed a set of C++ classes that facilitates history keeping of
particle tracks within the framework of Geant4. This software tool, hereafter
called J4HistoryKeeper, comes in handy in particular when one needs to stop
this history keeping for memory space economy at multiple geometrical
boundaries beyond which a particle shower is expected to start. In this paper
this software tool is described and applied to a generic detector model to
demonstrate its functionality.

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The categories of this paper are: patt-sol
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The categories of this paper are: hep-lat
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The categories of this paper are: cs
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The categories of this paper are: eess
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The categories of this paper are: supr-con
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The categories of this paper are: cmp-lg
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The categories of this paper are: chem-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-th
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The categories of this paper are: acc-phys
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The categories of this paper are: alg-geom
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The categories of this paper are: q-bio
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The categories of this paper are: solv-int
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The categories of this paper are: math-ph
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The categories of this paper are: q-fin
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The categories of this paper are: q-alg