Related papers: Speculations on ALEPH's Dijet Enhancement
We investigate the possibility that the excess of four-jet events in $e^+e^-$ collisions at LEP-1.5 which has been reported by the ALEPH Collaboration could be due to the production of charginos or neutralinos, followed by their decay into…
We review briefly the indications for some relatively light superpartners based on the ~$R_b$ ~anomaly and discuss the dependence of the potential increase in $R_b$ on the assumption about ~$R-$parity (non)conservation. We point out that…
ALEPH has reported a significant excess of four-jet events in the LEP runs above the Z^0 resonance, which however has not been confirmed by the other LEP collaborations. We assume here that this excess corresponds to a physics signal and…
We suggest that the anomalous 4-jet events recently reported by ALEPH may be the first indication of low scale technicolour. According to our interpretation about half of the events are due to resonantly enhanced pair production of charged…
The ALEPH collaboration has recently reported a significant excess of four-jet events at the LEP 1.5 and LEP 2. While not yet confirmed by the other collaborations, it was recently proposed that this excess may be explained by certain…
In this paper, we address the observability of four-jet signatures from light neutral and charged Higgs bosons at LEP2 energies in the framework of 2-Higgs Doublet Models (2HDMs). The main signal production channels are via $e^+ e^- \to Ah$…
Events with four distinct jets from e^+e^- collisions, collected by the OPAL detector at centre-of-mass energies between 130 and 184 GeV, are analysed for a peak in the sum of dijet masses. This search is motivated by the ALEPH…
We present the results of a calculation of the rate for the annihilation of an $e^+e^-$ pair into a jet containing an energetic photon and a single further jet at order $\alpha \alpha_{s}$. By comparing these results with the existing data…
We show that a recently proposed extension of QCD by the addition of a multiplet of scalars transforming as (2,2,1) under $SU(2)_L\times SU(2)_R\times SU(3)_ {colour}$ provides a natural and parameter-free explanation for many observed…
When the gluino is light and long lived, missing energy is a poor signature for both squarks and gluinos. Instead, $S_q S_q^*$ production in $e^+ e^-$ and $p \bar{p}$ collisions characteristically results in events with $\ge 4$ jets.…
We study the pair production of charginos in e+e- collisions followed by the decay via R-parity violating LQD operators. We determine the complete matrix element squared for chargino decays via LQD or LLE operators. We find regions in MSSM…
Possible spin-3/2 quark resonances would have a significant effect on high E$_{\mbox{\rm t}}$ jet production through their contribution to the subprocess $q+{\bar q}\rightarrow g+g$. Such enhancements are compared to a, recently reported,…
The first measurements of energy spectra and substructure of anti-$k_{T}$ jets in hadronic $Z^0$ decays in $e^+e^-$ collisions are presented. The archived $e^+e^-$ annihilation data at a center-of-mass energy of 91.2 GeV were collected with…
We study axion-like particles (ALPs) with quark-flavor-violating couplings at the LHC. Specifically, we focus on the theoretical scenario with ALP-top-up and ALP-top-charm interactions, in addition to the more common quark-flavor-diagonal…
Searches for the pair production of supersymmetric particles under the assumption that R-parity is violated via a single dominant LLEbar, LQDbar or UbarDbarDbar coupling are performed using the data collected by the ALEPH detector at LEP at…
The CMS Collaboration at the Large Hadron Collider (LHC) has observed two four-jet events with a total invariant mass of about 8 TeV; within each event, the jets can be paired into two dijets with invariant masses of 2 TeV each. These are…
Dijet production is studied in collisions of quasi-real photons radiated by the LEP beams at e+e- centre-of-mass energies sqrt(s)_ee=161 and 172 GeV. Jets are reconstructed using a cone jet finding algorithm in the range |eta(jet)|<2 and…
In previous work, we identified an anomalous number of events in the LHC jets+MET searches characterized by low jet multiplicity and low-to-moderate transverse energy variables. Here, we update this analysis with results from a new ATLAS…
We report on the calculation of the NLO QCD corrections to top quark pair production in association with two hard jets at the LHC. We take into account higher-order effects in both the production and decays of the top-quark pair. The latter…
Formation and evolution of the elliptic flow pattern in Pb+Pb collisions at sqrt{s}=5.5 ATeV and in Au+Au collisions at sqrt{s}=200 AGeV are analyzed for different hadron species within the framework of HYDJET++ Monte-Carlo model. The model…