181872289
Measurement of nucleon structure functions at x > 1 and large momentum transfer
120014689
Pion-helium scattering above the (3,3) resonance
Differential cross sections are reported for ..pi../sup +/+/sup 3,4/He elastic scattering at 260, 295, and 310 MeV and ..pi../sup -/+/sup 3,4/He at 295 MeV. The angular distributions )except for ..pi../sup -/+/sup 3/He) confirm the fixed angle (thetaapprox. =75/sup 0/) minimum seen at lower energies (caused by the (3,3) ..pi..+N resonance dominance) and show a deep minimum at thetaapprox. =110/sup 0/. Comparisons are made to ..pi..+d and the current discussion of pion excitation of intermediate dibaryon and ..delta..N states.
121665406
Quark-parton models and the neutron charge radius
32493630
Computer Modeling of Internal Targets in Electron Storage Rings
The effect of thin (1-50 ¿gm/cm2) internal targets on beam quality in electron storage rings is evaluated. The internal target is modeled assuming that scattering is the result of elastic collisions between the beam electrons and the target nuclei. A screened coulomb potential is used and single and plural scattering mechanisms are included. A storage ring particle tracking code, DIMAT, was modified to include the internal target model and used to obtain the results discussed. Beam particle loss distributions and beam envelope "growth times" are given and discussed in light of damping mechanisms inherent in electron storage ring designs.
121139038
CEBAF — a high energy, high duty factor electron accelerator for nuclear physics☆
Abstract The Nuclear Science Advisory Committee has recommended the construction of the Continuous Electron Beam Accelerator Facility (CEBAF) as proposed by the Southeastern Universities Research Association (SURA), a consortium of more than thirty institutions in the southeastern United States. The accelerator will be capable of delivering intense (Iave > 100 μA), quasi-continuous (duty Factor > 90%) beams of electrons with energies up to 4.8 GeV. Short (1.2 μs), intense (Ipk = 200 mA) pulses of electrons will be accelerated by passing twice through a conventional pulsed linac. The pulses then will be injected into and stored in a pulse stretcher ring, the circumference of which is close to the length of the electron pulse. During the period between pulses (1ms) the stored electrons will be extracted to yield a high duty factor beam. Delivery of arbitrarily polarized beams will be possible. Experimental facilities will include three end stations. Two will be used for experiments utilizing the primary electron beam; the third will serve as a tagged photon facility.
122290195
Off-shell effects in quasielastic electron nucleus scattering
Using the Ward-Takahashi identity, on-shell condition, bound Dirac equation and off-shell expansion, a reduced version of half off-shell virtual photon nucleon vertex has been suggested. The vertex are decomposed into several different order terms: the on-shell terms, first and second off-shell terms. The off-shell behaviour of the form factors is discussed in the one meson loop model. Using the reduced vertex and parametrized off-shell form factors the quasielastic response functions are calculated for several nuclei at ¦q¦–kf and for56Fe at large ¦q¦ up to 1.14 GeV/c and at −q2=0.9 (GeV/c)2. The Coulomb sums are evaluated and a comparison of the theoretical prediction with data is given. The off-shell electron nucleon cross section is calculated and compared with the “cc1” off-shell extrapolation.
14956759
Large N and the Dine-Rajaraman problem
Abstract We compute the effective action for scattering of three well-separated extremal brane solutions, in 11d supergravity, with zero p − transfer and small transverse velocities. Using an interpretation of the conjecture of Maldacena, following Hyun, this can be viewed as the large N limit of the Matrix theory description of three supergraviton scattering at leading order. The result is consistent with the perturbative supergravity calculation.
55383487
Operational Experience with Tevatron I Antiproton Source
The secondaries are transported down the AP2 line into the Debuncher ring. The Debdncher ring has a 207 x 23~ transverse acceptance and 4% momentum acceptance. The antiprotons are then rotated using 4.2 MV of 53 MHz R.F. to .4% Ap/p in 80 turns and the adIabatically debunched to .2% APIP. The antiproton are then stochastically cooled for 2 seconds in the transverse planes with 2-4 GHz cooling systems to 771 x 77. The antiproton are then extracted from the Debuncher and transported across the D/A line to the Accumulator.
117708238
STACKTAIL MOMENTUM COOLING IN THE FERMILAB ANTIPROTON SOURCE
122808498
Covariant field theory of the compactified closed bosonic string
We covariantly first-quantize, via the BRST approach, the closed bosonic string compactified on a torus — in particular the 18-dimensional theory with E8 × E8 gauge bosons. Further, we give the corresponding free field theory. Thus the model is ready for the introduction of string interactions, and may be very useful for the study of gauge interactions in string theories.
1147559
Evidence for the decay $B^0\to J/\psi \omega$ and measurement of the relative branching fractions of $B^0_s$ meson decays to $J/\psi\eta$ and $J/\psi\eta^{'}$
First evidence of the $B^0\to J/\psi\omega$ decay is found and the $B_{s}^0\to J/\psi\eta$ and $B_{s}^0\to J/\psi\eta^{\prime}$ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 $\mathrm{fb}^{-1}$ collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} = 7$ TeV. The branching fractions of these decays are measured relative to that of the $\mathrm{B}^0\to J/\psi\rho^0$ decay: $$\frac{Br(B^0\to J/\psi\omega)}{Br(B^0\to J/\psi\rho^0)} = 0.89 \pm0.19(stat)^{+0.07}_{-0.13}(syst)$$ $$\frac{Br(B^0_s\to J/\psi\eta)}{Br(B^0\to J/\psi\rho^0)} = 14.0 \pm 1.2(stat)^{+1.1}_{-1.5}(syst)^{+1.1}_{-1.0}(\frac{f_d}{f_s}),$$ $$\frac{Br(B^0_s\to J/\psi\eta^{\prime})}{Br(B^0\to J/\psi\rho^0)} = 12.7\pm1.1(stat)^{+0.5}_{-1.3}(syst)^{+1.0}_{-0.9}(\frac{f_d}{f_s}),$$ where the last uncertainty is due to the knowledge of $f_d/f_s$, the ratio of b-quark hadronization factors that accounts for the different production rate of $B^0$ and $B^0_s$ mesons. The ratio of the branching fractions of $B^0_s\to J/\psi\eta^{\prime}$ and $B^0_s\to J/\psi\eta$ decays is measured to be $$ \frac{Br(B^0_s\to J/\psi\eta^{\prime})}{Br(B^0_s\to J/\psi\eta)} = 0.90\pm0.09(stat)^{+0.06}_{-0.02}(syst).$$