Related papers: Quaero@H1: An Interface to High-pT HERA Event Data
We investigate an event excess in the reaction $e^+p \to e^+ X$ with large $x$ and high $Q^2$ observed at HERA and show that the events could naturally be interpreted as a signature of the production of the scalar top quarks (stops) in a…
Searches for New Particles including future sensitivity prospects are reviewed. The main focus is placed on results obtained at LEP, HERA and the Tevatron on generic searches such as searches for excited fermions, searches for leptoquarks…
A light stop, with an R-parity-violating coupling $\lambda'_{131}$, has been suggested as an explanation of the excess in high-$Q^2$ neutral current events observed at the HERA collider. We show that in this scheme a corresponding excess in…
Results of a general search for new phenomena at high transverse momentum and of a dedicated search for events with isolated leptons and missing transverse momentum are reported. These searches were performed on a data sample collected at…
The status of searches for new particles and new physics during the past year at the Fermilab Tevatron, at HERA and at LEP is summarized. A discussion of the hints for the Standard Model Higgs boson from LEP2 data is presented. Searches for…
Over the last two decades, the HERA collider has provided a large amount of new information about QCD dynamics at high energy. While the most appreciated are the measurements of the proton structure functions in a wide range of parton…
Many explanations for the excess high-Q^2 $e^+p \to e^+X$ events from H1 and ZEUS at HERA have been proposed each with criticisms. We propose a new method to distinguish different models by looking at a new distribution which is insensitive…
The excess of high-$Q^2$ events found by H1 and ZEUS at HERA in $e^+p$ deep-inelastic scattering above the Standard Model prediction motivates us to calculate the NLO QCD corrections to the HERA scalar leptoquark (or squark) production…
Searches for physics beyond the Standard Model of particle physics are performed at accelerators worldwide. Although having poorer detection capabilities and large beam uncertainties, ultra high energy cosmic ray (UHECR) experiments present…
Searches for contact interactions, leptoquark bosons and excited fermions carried out at the HERA ep collider are presented here. The searches are based on ~ 40 pb^-1 of e+ p data per experiment collected at a centre of mass energy ~ 300…
In this review there is first a survey of the HERA data. Then we discuss the theory response including querying the consistency of the data, compositeness, contact terms, and leptoquarks including as a special case the R symmetry violating…
A search for scalar and vector leptoquarks coupling to first generation fermions is performed in the H1 experiment at the ep collider HERA. The analysis uses e^- p data collected in 1998 and 1999 at a centre-of-mass energy of 320 GeV,…
We present possible strategies for anomaly detection of rare particle decays and exotic hadrons, such as pentaquarks, in low-background environments such as those characteristic of diffractive events and ultraperipheral \pp, \pA, or \AAcoll…
Measures taken to extend the acceptance of the H1 detector at HERA for photoproduction events are described. These will enable the measurement of electrons scattered in events in the high y range 0.85 < y < 0.95 in the 1998 and 1999 HERA…
The latest results from the H1 and ZEUS collaborations which challenge the QCD description of high energy $ep$ collisions are presented. Data from HERA continue to provide precision measurements and are compared to the latest theoretical…
A search for excited neutrinos produced in electron--proton collisions is performed using a data sample corresponding to an integrated luminosity of 114 pb$^{-1}$ recently collected by the H1 detector at HERA. In absence of a signal, the…
The search for events containing isolated leptons (electrons or muons) and missing transverse momentum produced in $e^{\pm}p$ collisions is performed with the H1 detector at HERA in the period 1994--2005. The analysed data sample…
The analysis of events containing multiple high Pt leptons (electrons and muons) produced in ep collisions has been performed with the H1 and ZEUS detectors at HERA, using the full data sets collected by the experiments in the period…
We explore interpretations of the anomaly observed by H1 and ZEUS at HERA in deep-inelastic e^+ p scattering at very large Q^2. We discuss the possibilities of new effective interactions and the production of a narrow state of mass 200 GeV…
A search for scalar and vector leptoquarks coupling to first generation fermions is performed using the e^+p and e^-p scattering data collected by the H1 experiment between 1994 and 2000. The data correspond to a total integrated luminosity…