A Search for resonance decays to lepton + jet at HERA and limits on leptoquarks

A search for narrow-width resonances that decay into electron+jet or neutrino+jet has been performed with the ZEUS detector at HERA operating at center-of-mass energies of 300 and 318 GeV. An integrated e+p luminosity of 114.8 pb-1 and e-p luminosity of 16.7 pb-1 were used. No evidence for any resonance was found. Limits were derived on the Yukawa coupling as a function of the mass of a hypothetical resonance that has arbitrary decay branching ratios into electron+quark or neutrino+quark. These limits also apply to squarks predicted by R-parity-violating supersymmetry. Limits for the production of leptoquarks described by the Buchmuller-Ruckl-Wyler model were also derived for masses up to 400 GeV. For Yukawa coupling of 0.1, leptoquark masses up to 290 GeV are excluded.

Note:

30 pages, 12 figures, 6 tables Report-no: DESY-03-041

14.80.-j
13.60.-r
electron p: colliding beams
positron p: colliding beams
narrow resonance: search for
final state: (jet lepton)
leptoquark: mass
lower limit
squark
supersymmetry

References(41)

Figures(13)

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(
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)
,
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(
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)
,
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(
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)

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(
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,
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(
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)
,
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(
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