相关论文: Beyond the Standard Model at HERA
We review supersymmetry models with and without R-parity. After briefly describing the Minimal Supersymetric Standard Model and its particle content we move to models where R-parity is broken, either spontaneously or explicitly. In this…
All experimental measurements of particle physics today are beautifully described by the Standard Model. However, there are good reasons to believe that new physics may be just around the corner at the TeV energy scale. This energy range is…
A search for scalar top quarks in R-parity violating supersymmetry is performed in e^+ p collisions at HERA using the H1 detector. The data, taken at sqrt{s}=319 GeV and 301 GeV, correspond to an integrated luminosity of 106 pb^-1. The…
A search for physics beyond the Standard Model has been performed with high-Q^2 neutral current deep inelastic scattering events recorded with the ZEUS detector at HERA. Two data sets, e^+ p \to e^+ X and e^- p \to e^- X, with respective…
These four lectures constitute a gentle introduction to what may lie beyond the standard model of quarks and leptons interacting through $SU(3)_c \otimes SU(2)_L \otimes U(1)_Y$ gauge bosons, prepared for an audience of graduate students in…
Various searches for leptoquarks, scalar quarks in $R_p$-violating supersymmetric models, and excited fermions performed by the HERA experiments H1 and ZEUS are reviewed. No evidence for new particle production was observed from data…
Recent results on the searches for new physics in ep collisions at HERA using the ZEUS and H1 detectors are presented. No evidence for excited fermions or supersymmetric particles within the context of the Minimal Supersymmetric Standard…
Following a general introduction to open questions beyond the Standard Model, the prospects for addressing them in the new era opened up by the LHC are reviewed. Sample highlights are given of ways in which the LHC is already probing beyond…
We summarize two sets of signals at HERA in supersymmetric models with explicitly broken R-parity. (1) The resonant production of single squarks through an operator $L_1Q_i{ \bar D}_j$. (2) The MSSM production of a squark and a slepton…
The supersymmetric extension of the Standard Model can contain interactions violating the so-called R-parity symmetry. Such couplings would lead to the lepton and/or baryon number violation and modify deeply the phenomenology of…
In this talk I discuss some recent developments in physics beyond the Standard Model. After some initial comments on neutrino masses, I discuss the status of low-energy supersymmetry and finally turn to describing some recent work in…
Events with isolated leptons and missing transverse momentum are searched for in electron- or positron-proton collisions at HERA by the H1 and ZEUS experiments. Such events may be explained within the Standard Model by W boson production,…
In this work, we explore a well motivated beyond the Standard Model scenario, namely, R-parity violating Supersymmetry, in the context of light neutrino masses and mixing. We assume that the R-parity is only broken by the lepton number…
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…
This is an auspicious moment in experimental particle physics -there are large data samples at the Tevatron and a new energy regime being explored at the Large Hadron Collider with ever larger data samples. The coincidence of these two…
The R parity odd renormalizable Yukawa interactions of quarks and leptons with the scalar superpartners have the ability to violate the baryon and lepton numbers, change the hadron and lepton flavors and make the lightest supersymmetric…
We examine the stop production scenario for the anomalous excess of high $Q^2$ events observed at HERA, by taking into account the constraints coming from the leptoquark search at Tevatron and the atomic parity violation experiments. This…
R-parity conservation is an ad-hoc assumption in the most popular versions of supersymmetric scenarios. Hence R-parity violation (RPV) not only is allowed but, if induced by bilinear terms (bRPV), it also provides an explanation for the…
This is a brief review of experimental strategies for physics beyond the Standard Model based on the talk given in the ``Physics at LHC'' in Vienna, July 2004 \cite{vienna}. The emphasis is on Tevatron thematology and experience.
If a signal for physics beyond the Standard Model is observed at the Tevatron collider or LHC, we will be eager to interpret it. Because only certain observables can be studied at a hadron collider, it will be difficult or impossible to…