Related papers: Physics with Single Photons plus Missing Energy Fi…
A search for signals of new physics has been carried out in the channel p pbar -> gamma gamma + ETmiss. This signature is expected in various recently proposed supersymmetric (SUSY) models. We observe 842 events with two photons having…
Rare decays of the Z boson provide a sensitive probe for physics beyond the Standard Model (SM). This study investigates the $e^{+}e^{-} \to Z \to \nu\bar{\nu}\gamma$ process within the context of the Tera-Z programmes at future colliders…
We study the sensitivity for testing the anomalous triple gauge couplings $ZZ\gamma$ and $Z\gamma\gamma$ via the process $e^+e^-\to \nu \bar\nu \gamma$ at high energy linear colliders. For integrated luminosities of 500 $fb^{-1}$ and center…
Recent experimental results of searches for new phenomena performed at high energy colliders are reviewed. The results reported are based on data samples of up to 1 fb^-1 and 4 fb^-1 collected at HERA and at the Tevatron, respectively. No…
A search for supersymmetric particles in events with large missing transverse momentum, heavy flavor jet candidates and no leptons (e,mu) in sqrt{s} = 7 TeV proton-proton collisions is presented. In a data sample corresponding to an…
Supersymmetry, if realized in Nature, predicts the existence of new particles, as chargino and neutralino, which might manifest themselves with peculiar signatures. Three leptons and large missing transverse energy in the event could signal…
One of the simplest extensions of the Standard Model (SM) is an extra U(1) gauge group under which SM matter does not carry any charge. The associated boson -- the hidden photon -- then interacts via kinetic mixing with the ordinary photon.…
This paper presents the observation of the electroweak production of single top quarks in the D0 detector at the Fermilab Tevatron Collider at a center-of-mass energy of 1.96 TeV. Events containing an isolated electron or muon and missing…
Results are reported from a search for supersymmetry with gauge-mediated supersymmetry breaking in electroweak production. Final states with photons and large missing transverse energy (MET) were examined. The data sample was collected in…
We have studied anomalous four-photon couplings in the $\mu^+\mu^- \rightarrow \mu^+ \gamma\gamma \mu^-$ scattering at a future muon collider. The collision energies of 3 TeV, 14 TeV, and 100 TeV are addressed. Both differential and total…
We present results of a search in 929 pb-1 of ppbar collisions at 1.96 TeV for the anomalous production of events containing a charged lepton (electron or muon) and a photon, both with high transverse momentum, accompanied by additional…
The CDF experiment reported a lepton photon missing transverse energy (E_T) signal 3 sigma in excess of the Standard Model prediction in Tevatron Run I data. The excess can be explained by the resonant production of a smuon, which…
We present three recent photon analyses from data collected at the Fermilab Tevatron: measurements of the direct photon pair production cross section at CDF and D0, measurements of azimuthal decorrelations and multiple parton interactions…
We study the rare decay process of $Z$ boson into photon, accompanied by a CP-even or CP-odd scalar. We present the analytical delineation of the processes through the model-independent parametrizations of the new physics couplings and,…
Searches for the production of electroweak supersymmetric particles decaying into final states with exactly two isolated, oppositely-charged leptons (electrons, muons), no reconstructed jets and missing transverse momentum are performed…
We present the results of a search in pbar-p collisions at root-s=1.8 TeV for anomalous production of events containing a photon and a lepton (e or mu), both with large transverse energy, using 86 pb-1 of data collected with the Collider…
Motivated by recent studies of supersymmetry in higher-dimensional spaces, we discuss the experimental signatures of a superlight gravitino, mass < 0.001 eV. We concentrate on the process (e- gamma -> selectronR gravitino) as a probe of…
We provide a detailed investigation of single-photon production processes in $e^+e^-$ collisions with missing momenta carried by neutrinos or neutralinos. The transition amplitudes for both processes can be organized into a generic…
A study of Z-boson pair production in e+e- annihilation at center-of-mass energies between 190 GeV and 209 GeV is reported. Final states containing only leptons, (l+l-l+l- and l+l-nn), quark and lepton pairs, (qql+l-, qqnn) and only hadrons…
Results of a search for new phenomena in events with an energetic photon and large missing transverse momentum with the ATLAS experiment at the LHC are reported. Data were collected in proton--proton collisions at a center-of-mass energy of…