Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Physics with Far Detectors at Future Lepton Colliders   At the Large Hadron Collider (LHC), several far detectors such as FASER and
MATHUSLA have been proposed to target the long-lived particles (LLPs) featured
with displaced vertices. Naturally one question arises as to the feasibility of
installing similar far detectors at future lepton colliders like the CEPC and
FCC-ee. Because of the different kinematics of final state particles and the
freedom to locate both the experiment hall and the detectors, the future lepton
collider with an additional far detector may play a unique role in searching
for LLPs. In this study, we consider various locations and designs of far
detectors at future $e^- e^+$ colliders and investigate their potentials for
discovering LLPs in the physics scenarios including exotic Higgs decays, heavy
neutral leptons, and the lightest neutralinos. Our analyses show that the
kinematical distinctions between the lepton and hadron colliders render the
optimal positions of far detectors lying at the direction perpendicular to the
collider beams at future $e^- e^+$ colliders, in contrast to the LHC where a
boost in the forward direction can be exploited. We also find that when
searching for LLPs, such new experiments with far detectors at future lepton
colliders may extend and complement the sensitivity reaches of the experiments
at the future lepton colliders with usual near detectors, and the present and
future experiments at the LHC. In particular, we find that, for the theory
models considered in this study, a MATHUSLA-sized far detector would give a
modest improvement compared to the case with a near detector only at future
lepton colliders.

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The categories of this paper are: cond-mat
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The categories of this paper are: nlin
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The categories of this paper are: astro-ph
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The categories of this paper are: q-alg
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The categories of this paper are: hep-th
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The categories of this paper are: hep-lat
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The categories of this paper are: bayes-an
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The categories of this paper are: funct-an
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The categories of this paper are: q-fin
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The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con
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The categories of this paper are: adap-org
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The categories of this paper are: quant-ph
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The categories of this paper are: physics
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The categories of this paper are: plasm-ph
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The categories of this paper are: comp-gas