摘要:

Results from searches for new particles ine+e−collisions at energies of 161 GeV and 172 GeV at LEP will be reported. Limits for the production of Higgs bosons, SUSY particles and excited leptons are summarized. The “four jet puzzle” is reviewed. ©1997 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.54462

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

We discuss the results of a global fit to precision data in supersymmetric models. We consider both gravity- and gauge-mediated models. As the superpartner spectrum becomes light, the global fit to the data typically results in larger values of&khgr;2.We indicate the regions of parameter space which are excluded by the data. We discuss the additional effect of theB(B→Xs&ggr;)measurement. Our analysis excludes chargino masses belowMZin the simplest gauge-mediated model with&mgr;>0,with stronger constraints for larger values oftan &bgr;.©1997 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.54472

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Preliminary electroweak results are discussed from the Fermilab experiments, CDF and DO&slash;, based on Tevatron run 1b data. These include an updated precision measurement of theWmass which when combined with previous Tevatron, CERNSp¯pS,and LEP-II results gives a combined world averageMW=80.40±0.08 GeV/c2.Also presented are new limits on anomalous gauge boson self-couplings, measurement of theWcharge asymmetry,&sgr;⋅B(W→&tgr;&ngr;&tgr;),and limits on quark/lepton compositeness from high mass Drell-Yan production. ©1997 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.54494

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

The Tevatron at Fermilab has recently completed a four year run ofpp¯collisions ats=1.8 TeV.During this run (Run I), the two large experiments, CDF and DO&slash;, recorded over100 pb−1data each. Analysis of this data is now in progress, including a vigorous search for new phenomena beyond the Standard Model. Here is a review of a subset of these explorations including a selection of topics on the searches for supersymmetry and leptoquarks. ©1997 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.54446

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

We classify the sensitivities of the future high energy hadron and electron colliders, such as the LHC and the future Linear Colliders, to probing all the next-to-leading order (NLO) bosonic operators for studying the electroweak symmetry breaking (EWSB) mechanism. We first develop a power counting rule (a generalization of Weinberg’s counting method for the nonlinear sigma model) for the electroweak theories formulated by the chiral Lagrangian. Then, we formulate the Longitudinal-Goldstone Boson Equivalence Theorem as a physical criterion to discriminate the scattering processes that are not sensitive to the EWSB sector. Thecomplementarityof different scattering processes via different colliders for a complete probe of all these NLO effective operators is demonstrated. ©1997 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.54448

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Key electroweak measurements performed by the SLD collaboration at the SLC are described and recent results given. The left-right cross-section asymmetry,ALR,has been updated to include the 1996 data. It remains the single most precise measurement ofsin2 &thgr;Weffand it is compared to the LEP results. The polarized differential cross section forb-quarks is measured and is used to perform a unique direct measurement of the parity violation parameter forbquarks,Ab.The excellent capability to perform secondary vertexing at SLC with CCD-based vertex detectors is described, including first physics results with the new detector VXD3. The vertexing is used to full advantage to make a highly pureBtag to measure the fraction of hadronicZ0decays going tobquarks,Rb.The vertexing, in combination with electron-beam polarization, is used to measureBd0mixing. The prospects for making aBs0mixing measurement are excellent given good SLC performance in the upcoming SLC run(s). ©1997 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.54489

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

NOMAD is an experiment searching for&ngr;&mgr;&zigarr;&ngr;&tgr;(&ngr;e)oscillations in the CERN Wide Band Neutrino Beam. After its completion (August 1995), the detector has performed according to expectations and has been taking data since. A preliminary analysis, based upon the event sample collected in 1995, saw no evidence for oscillations, thus setting an upper limit in the mixing angle for high&Dgr;m2values ofsin2 2&thgr;<4×10−3for&ngr;&mgr;&zigarr;&ngr;&tgr;andsin2 2&thgr;<2×10−3for&ngr;&mgr;&zigarr;&ngr;e(90&percent; C.L.). ©1997 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.54447

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

We are searching for&ngr;&mgr;to&ngr;&tgr;oscillation via the observation of the decay of the tau lepton generated in charged current interactions of&ngr;&tgr;.The beam exposure started in May 1994 and will finish in Nov. 1997. A partial sample of neutrino interactions reconstructed by the electronic detector have been located in the emulsion target and analyzed to search for tau decays. No candidate has been observed. This result translates in an upper limit on the oscillation parametersin2 2&thgr;=4.5×10−3.Within 2 years, a sensitivity tosin2 2&thgr;=2×10−4will be reached. ©1997 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.54490

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Deep-inelastic scattering events produced in position proton collisions with momentum transfers up to≈30000 GeV2have been observed at HERA using the data sample from the years 1994–1996 recorded by the H1 detector. The number of observed neutral and charged current events is compared to the extrapolated standard DIS cross-section expectation. Possible explanations beyond the Standard Model are discussed. A search for Rp-violating supersymmetric squarks based on a much smaller data sample is summarized. ©1997 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.54491

出版商:AIP    

年代:1997

数据来源: AIP

摘要:

Results are presented on a number of searches for new physics inepcollisions at HERA using the ZEUS and H1 detectors. Limits are presented on the production of excited fermions, contact interactions, as well as a heavy right handed neutrino andWRboson. Also presented are ZEUS results on the excess of events at highxandQ2.©1997 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.54468

出版商:AIP    

年代:1997

数据来源: AIP