122509981
Search for direct electron production in p-p and p-Be collisions at 12 GeV/c
We have made a systematic search for direct e/sup +/ and e/sup -/ production in p-p and p-Be collisions at 12 GeV/c incident proton momentum. Data were collected at c.m. angles of 20/sup 0/, 35/sup 0/, 63/sup 0/, and 84/sup 0/. We find no evidence for the previously reported rise in the ratio e/..pi.. at low momentum transfer. The data are consistent with zero direct electron production from other than previously known sources.
120089999
Two-body final states in K-p interactions at 14.3 GeV/c
Event selection and weighting. In Fig. 1 a), the distribution of the square of the missing mass to the K0 in all zero-prong plus one K ~ events is displayed; a clear neutron signal is visible with a half-width of approximately 0.4 (GeV)L In the study of reaction (1) we use all events with missing mass less than the A(1236) mass. The cross-section is corrected for the few neutron events above this cut by double-counting the symmetrical region below the neutron mass. We also correct for the background reaction
122629720
K - p elastic scattering at 14.25 GeV/ c
Abstract The K − p differential and total elastic cross-sections have been measured at 14.25 GeV/ c . The results have been compared with various Regge models.
118557074
Anti-p p annihilations into pi+ pi-, k+ k-, pi+ pi- pi0, and pi+ pi- neutrals near center-of-mass energy 2200 mev
107450647
Hodoscope subgroup summary microchannel plate photodetectors
A brief discussion is given of the possible uses of microchannel plate photomultipliers and multichannel or multianode photodetectors at ISABELLE.
125547556
A NUMERICAL and ANALYTICAL STUDY OF ANOMALOUS PROPAGATION OF ELECTRICAL IMPULSES IN DAMAGED HEART FIBERS
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15327116
Design of the NLC Positron Source
The design of the positron source for the Next Linear Collider (NLC) is presented. The key features of this design include accelerating positrons at an L-band frequency (1428 MHz) and using a rotating positron target with multi-stage differential pumping. Positron yield simulations show that the L-band design yields at the source 2.5 times the beam intensity required at the interaction point and is easily upgrade to higher intensities required for the 1 TeV NLC upgrade. Multi-bunch beam loading compensation schemes in the positron capture and booster accelerators and the optics design of the positron booster accelerator are described. For improved source efficiency, the design boasts two parallel positron vaults adequately shielded from each other such that one serves as an on-line spare.
738055
The linac and booster RF systems for a dedicated injector for SPEAR
A 120 MeV, 2856 MHz, traveling wave linear accelerator (linac), with a microwave gun, alpha magnet, and chopper, has been built at the Stanford Synchrotron Radiation Laboratory (SSRL) as a preinjector for and along with a 3 GeV, 358.54 MHz, booster synchrotron ring. The resulting injector will be available on demand to fill the Stanford Positron-Electron Accelerator Ring (SPEAR), which is a storage ring now dedicated to synchrotron light production. A description is given of the injector's two separate and different frequency RF systems. Synchronization of the two, non-harmonic systems is achieved through the linac's chopper. Some of the interesting mechanical and electrical details are discussed and the operating characteristics of the linac and ring RF are highlighted.<<ETX>>
22303829
RF Phase Focusing in Portable X-Band, Linear Accelerators
In order to minimize the size and weight of the x-ray or neutron source for a series of portable radiographic linear accelerators, the x-ray head was packaged separately from the rest of the system and consists of only the linac accelerating structure, electron gun, built-in target, collimator, ion pump and an RF window. All the driving electronics and cooling are connected to the x-ray head through flexible waveguide, cables, and waterlines. The x-ray head has been kept small and light weight by using the RF fields for radial focusing, as well as for longitudinal bunching and accelerating the beam. Thus, no external, bulky magnetic focusing devices are required. The RF focusing is accomplished by alternating the sign of the phase difference between the RF and the beam and by tapering from cavity to cavity the magnitude of the buncher field levels. The former requires choosing the right phase velocity taper (mix of less than vp=c cavities) and the latter requires the right sizing of the cavity to cavity coupling smiles (irises).
121827072
Measurement of asymmetry in spin-dependent e-p resonance-region scattering
The first measurements are reported of the asymmetry in resonance-region scattering of longitudinally polarized electrons by longitudinally polarized protons. Data have been obtained at Q/sup 2/=0.5 and 1.5 (GeV/c)/sup 2/ in the missing-mass range W=1.1--1.9 GeV. Results are compatible with a multipole analysis of single-pion electroproduction. The spin-dependent behavior is consistent with a duality mechanism as in the unpolarized case.
35388009
Operating Experience with the Polarized Electron Gun at SLAC
During the two years of operation of the SLAC Polarized Electron Gun (PEGGY), the electron intensity delivered to the target has increased from 7 x 10/sup 7/ e/sup -//pulse to 1 x 10/sup 9/ e/sup -//pulse. The polarization is 0.85 with no measurable degradation caused by acceleration through the linear accelerator. The predominant cause of downtime is replenishment of lithium, which now averages 43 hours. The lifetime of a lithium load is about 175 hours.