12503564
Prompt Photons in Photoproduction at HERA
First inclusive measurements of isolated prompt photons in photoproduction at HERA have been made with the ZEUS detector. Cross sections are given as a function of the pseudorapidity and the transverse energy of the photon, for E_T^gamma > 5 GeV in the gamma-p centre-of-mass energy range 134-285 GeV. Comparisons are made with predictions from LO Monte Carlo models and NLO QCD calculations. For forward eta^gamma (proton direction) good agreement is found, but in the rear direction all predictions fall below the data.
119383752
Prompt photon processes in photoproduction at HERA
Abstract We present results for the photoproduction of inclusive prompt photons and for prompt photons accompanied by jets, measured with the ZEUS detector at HERA. Cross sections as a function of pseudorapidity and transverse energy are presented for 5 E T γ E T jet > 5 GeV in the centre of mass energy range 120–270 GeV. Comparisons are made with predictions from leading logarithm parton shower Monte Carlos and next-to-leading order QCD calculations using currently available models of the photon structure. NLO QCD calculations describe the shape and magnitude of the measurements reasonably well.
118615128
Searches for Physics Beyond the Standard Model at CMS
Recent results on searches for physics beyond the Standard Model at Large Hadron Collider are presented, based on early LHC data in proton-proton collisions at $\sqrt{s} = 7$ TeV collected by the CMS experiment. Prospects of early SUSY searches at CMS are also outlined.
124508354
The Response of CMS Combined Calorimeters to Single Hadrons, Electrons and Muons
We report on the response of the combined CMS electromagnetic (EB) and hadronic barrel (HB) calorimeters to hadrons, electrons and muons in a wide momentum range from 1 to 350 GeV/c. To our knowledge, this is the widest range of momenta in which any calorimeter system is studied. These tests, carried out at the H2 beam-line at CERN, provide a wealth of information, especially at low energies. We analyze in detail the dierences in total calorimeter response to charged pions, kaons, protons and antiprotons and discuss the underlying phenomena. These data will play a crucial role in the thorough understanding of jets in CMS.
122695172
Nonlinear beam dynamics experiments at the IUCF cooler ring
Results of nonlinear beam dynamics experiments at the IUCF Cooler Ring in past two years are discussed. Our experiments include studies on (1) betatron motion at 1-D resonance island, (2) linear coupling correction, (3) Hamiltonians determined experimentally from 2-D difference and sum resonances, (4) longitudinal phase space tracking, (5) beam response to RF phase modulation, (6) beam response to RF voltage modulation, (7) synchro-betatron coupling induced by dipole field modulation and (8) attractors of a weak dissipative Hamiltonian system.<<ETX>>
56406921
Beam extraction system for the cooler injector synchrotron at IUCF
The Cooler Injector Synchrotron (CIS) being built at IUCF will serve as an injector for the existing IUCF Cooler Ring. The beam extraction from CIS and injection to the Cooler Ring include the the orbit bump, extraction kicker, septum magnet in the CIS ring, the transport beam line, and injection part to the Cooler ring. After extracted from CIS ring with a traveling wave fast kicker (15 mrad) and a Lambertsen septum, beams are transported by the beam line BL9 to the cooler injection point and injected into the cooler ring by a fast traveling wave injection kicker.
116942523
Microwave instability near transition energy
Monte Carlo simulation for the microwave instability agrees with analytic calculation solving the Vlasov equation, provided that bunch shape distortion due to coupling is taken into account. 9 refs., 2 figs.
118516615
Emergence of supersymmetry on the surface of three-dimensional topological insulators
We propose two possible experimental realizations of a (2 + 1)-dimensional spacetime supersymmetry at a quantum critical point on the surface of three-dimensional topological insulators. The quantum critical point between the semi-metallic state with one Dirac fermion and the s-wave superconducting state on the surface is described by a supersymmetric conformal field theory within the ϵ-expansion. We predict the exact voltage dependence of the differential conductance at the supersymmetric critical point.
117280850
Partial Siberian snake experiment at the AGS
A 9° solenoidal spin rotator or 5% partial Siberian snake was used to successfully accelerate polarized protons for the first time to 10.8 GeV kinetic energy in the Brookhaven AGS. It was found that a 5% partial snake can effectively overcome 18 imperfection resonances in this energy range. We also observed an interference between the spin flip induced by an intrinsic resonance and linear coupling due to the solenoid field of the partial snake.