It is widely accepted that the next lepton collider beyond a Higgs factory would require center-of-mass energy of the order of up to 15 TeV. Since, given reasonable space and cost restrictions, conventional accelerator technology reaches its limits near this energy, high-gradient advanced acceleration concepts are attractive. Advanced and novel accelerators (ANAs) are leading candidates due to their ability to produce acceleration gradients on the order of 1-100 GV/m, leading to compact acceleration facilities. However, intermediate energy facilities (IEF) are required to test the critical technology elements on the way towards multi-TeV-class collliders. Here a science case for a 20-100 GeV center-of-mass energy ANA-based lepton collider that can be a candidate for an intermediate energy facility is presented. The IEF can provide numerous opportunities for high energy physics studies including precision Quantum Chromodynamics and Beyond the Standard Model physics measurements, investigation of charged particle interactions with extreme electromagnetic fields, and exploring muon and proton beam acceleration. Possible applications of this collider include the studies of γγ and electron beam-fixed target/beamdump collider designs. Thus, the goal of the proposed IEF is to both carry out particle physics measurements in the 20-100 GeV ranges as well as to serve as an ANA demonstrator facility.

Report of the Higgs working group for the Workshop `Physics at TeV Colliders', Les Houches, France, 21 May - 1 June 2001. It contains 7 separate sections: A. Theoretical Developments B. Higgs Searches at the Tevatron C. Experimental Observation of an invisible Higgs Boson at LHC D. Search for the Standard Model Higgs Boson using Vector Boson Fusion at the LHC E. Study of the MSSM channel $A/H \to \tau \tau$ at the LHC F. Searching for Higgs Bosons in $t\bar t H$ Production G. Studies of Charged Higgs Boson Signals for the Tevatron and the LHC

The branching ratio for inclusive ψ production in ψ(1S) decays is measured to be (0.11 ± 0.04 ± 0.02)%. © 1989.

Using the CLEO detector, we have measured the branching ratios for the exclusive decays of the Ds+ meson into K*0K+, K0K+, and K*+K0 relative to the decay Ds+→φπ+ to be close to unity. We have also measured the mass diference between the Ds+ and D+ meson to be 98.5±1.5 MeV/c2. © 1989.

We have measured upper limits on branching fractions for rare exclusive decays of B mesons arising from one-loop diagrams in the standard model of electroweak interactions. We also obtain an upper limit for the lepton-number-violating decay B0→μ±e∓. © 1989.

Using the CLEO detector at the Cornell Electron Storage Ring, we have searched for two-photon production of charmonium in four-track final states. We have measured Γγγ(ηc)=5.9+2.1-1.8±1.9 keV, and we have obtained 95% CL upper limits of Γγγ(Xc0)<6.2 keV and Γγγ(Xc2)<1.0 keV. © 1990.

Using the CLEO detector at the Cornell Electron Storage Ring, we have found evidence for L=1 charmed mesons in e+e- annihilations. We observe a D**0 state at mass 2461±3±1 MeV/c2 and width 20-12-10+9+9 MeV/c2 decaying to D+-. We also see an enhancement in the m(D*+-)-m(D*+) mass-difference spectrum and by examining D*+ decay-angle dependence, we see structure consistent with two states decaying to D*+-. We observe a lower-mass state, at mass (2428±3±2) MeV/c2 and width (23-6-4+8+10) MeV/c2, assuming that the higher-mass component is from the decay D**0(2461)D*+-. We present arguments for the spin-parity assignments of these states. We also report observation of candidate L=1 cs» state decaying to D*+Ks0. © 1990 The American Physical Society.

We have searched for neutrinoless decays into three charged particles. Evidence of such decays would demonstrate nonconservation of lepton flavor and, in some cases, lepton number. We see no signal for any such neutrinoless decays and set upper limits on their branching fractions. © 1990 The American Physical Society.

Using the CLEO detector, we present a measurement of the mass of the charged charmed strange baryon Ξ+c and its neutral counterpart the Ξ0c. The Ξ+c is observed through its decay to Ξ-π+π+, and its mass is measured to be (2467±3±4) MeV. The isospin mass splitting of the Ξc system is found to be M(Ξ+c)-M(Ξ0c)=(-5±4±1)MeV. © 1989.

We present evidence from the CLEO detector for the charmed strange baryon c0. It is seen in nonresonant e+e- annihilations at s of 10.5 GeV through its decay. The measured mass is 2471. © 1989 The American Physical Society.