59889859
Computer facilities for Isabelle data handling
The analysis of data produced by Isabelle experiments will need a large system of computers. Included in the array should be a substantial computer system at each Isabelle intersection in use. These systems must include enough computer power to keep experimenters aware of the status of the experiment. This will require at least one very fast sophisticated processor in the system, the size depending on the experiment. Other features of the intersection systems must be a good, high speed graphic display, ability to record data on magnetic tape at 500 to 1000 KB, and a high-speed link to a central computer. The operating system software must support multiple interactive users. A substantially larger capacity computer system, shared by the six intersection region experiments, must be available with good turnaround for experimenters while Isabelle is running. The computer mainframes should ideally be compatible members of the same family of computers. A very large computation load will be generated by the post experiment data reduction. Much of this may have to be run at lower priority. A computer support group will be required to maintain the computer system and to provide and maintain software common to all experiments. Such software support maymore » include providing a compatible compiler. Special superfast computing hardware or special function processors constructed with microprocessor circuitry may be necessary both in the data gathering and data processing work. Thus, both the local and central processors should be chosen with the possibility of interfacing such devices in mind.« less
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
125547556
A NUMERICAL and ANALYTICAL STUDY OF ANOMALOUS PROPAGATION OF ELECTRICAL IMPULSES IN DAMAGED HEART FIBERS
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120061510
Measurement of wide-angle elastic scattering of pions and protons off protons
A comprehensive measurement of the differential cross section for ..pi../sup + -/p and pp elastic scattering has been made at large center-of-mass angles. ..pi../sup -/p and pp scattering were measured with incident laboratory momenta ranging from 2 to 9.5 GeV/c. ..pi../sup +/p scattering was measured with momenta from 2 to 6.3 GeV/c. Scattering angles were in the range -0.3 < or approx. = costheta/sub c.m./ < or approx. = 0.4. The results of the experiment are compared to constituent models and statistical models.
117016085
Inclusive production of lambda and neutral kaon in K−p interactions at 3.93 GeV/c and 14.3 GeV/c
SummaryLambda and neutral-kaon production is studied in K−p interactions at 3.93 and 14.3 GeV/c. Topological inclusive cross-sections are given at both energies. Invariant cross-sections for lambdas and neutral kaons are presented as a function of the Feynmanx-variable and are found to decrease in magnitude and vary their shapes with energy. The

$$AK\overline K $$

 production, which represents (9±2)% and (29±3)% of the lambda inclusive cross-section at 3.93 GeV/c and 14.3 GeV/c respectively, yields mainly backward lambdas. The shapes of the transverse-momentum invariant distributions vary withx, but are roughly independent of energy. The lambda polarization is studied as a function ofx at both incident momenta: for fast lambdas it is negative, as observed in reactions where nucleon exchange is dominant.RiassuntoSi studia la produzione di particelle lambda e di kaoni neutri nelle interazioni K−p a 3.93 e 14.3 GeV/c. Per entrambi i valori dell'energia si danno le sezioni d'urto inclusive topologiche. Si presentano le sezioni d'urto invarianti per particelle lambda e kaoni neutri in funzione della variabilex di Feynman e si trova che diminuiscono in grandezza e cambiano di forma con l'energia. La produzione di

$$AK\overline K $$

, che rappresenta il (9±2)% e il (29±3)% della sezione d'urto inclusiva delle particelle lambda rispettivamente a 3.93 GeV/c e 14.3 GeV/c, dà per lo più particelle lambda che vanno all'indietro. Gli andamenti delle distribuzioni invarianti dell'impulso trasversale variano conx, ma sono approssimativamente indipendenti dall'energia. Si studia la polarizzazione delle particelle lambda in funzione dix per entrambi i valori dell'impulso incidente: per particelle lambda veloci è negativa, come si è osservato in reazioni in cui predomina lo scambio di nucleoni.РезюмеИсследуется рождение ламбда и нейтрального каона в K−p взаимодействиях при 3.93 ГэВ/с и 14.3 ГэВ/с. При обеих энергиях приводятся топологические инклюзивные поперечные сечения. Инвариантные поперечные сечения для ламбда и нейтральных каонов представлены в виде функции фейнмановскойx переменной. Получено, что поперечные сечения уменьшаются по величине и изменяют свою форму с энергией.

$$AK\overline K $$

 рождение, которое составляет соответственно (9±2)% и (29±3)% ламбда инклюзивного поперечного сечения при 3.93 ГэВ/с и 14.3 ГэВ/с, образует в основном ламбда-частицы, летящие в обратном направлении. Формы инвариантных распределений для поперечного импульса изменяются с «x», но вгрубом приближении не зависят от энергии. Исследуется поляризация ламбда, как функцияx для обоих начальных испульсов: для быстрых ламбда-частиц поляризация отрицательная, как наблюдается в реакциях, где доминирует нуклонный обмен.
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.
55891907
Recent Beam Performance and Developments at SLAC
The purpose of this paper is to describe recent developments at SLAC which have contributed to improvements in beam operation. The paper will be divided into two parts. The first will summarize overall beam performance and operational efficiency in delivering beams to various experiments. The second will be devoted to specific developments such as the achievement of higher energies, increasingly narrow energy spectra, higher beam breakup current thresholds, chopped beams and improvements in pulse-to-pulse operation. The discussion will include a description of various new pulsed devices such as pulsed quadrupoles, improvements in the positron source and new beam loading measurements obtained for very short pulses.
7087559
Update on the High-Current Injector for the Stanford Linear Collider
The high current injector has become operational. There are two crucial areas where improvements must be made to meet collider specifications: 1. While the injector can produce up to 1011 e-in a single S-band bucket, initially much of this charge was captured in a low energy tail and was thus not suitable for transport through the accelerator and injection into the damping ring. 2. Pulse to pulse position jitter has been observed, resulting in transverse wake fields which increase beam emittance. The problems described above contribute to substantial current loss during transport from the injector (40 MeV) to the SLC damping ring (1.2 GeV). Experimental studies are continuing with the aim of understanding and improving beam characteristics including bunch length, pulse to pulse stability and emittance. The present status of these studies is reported.
6208495
Accelerator Structures for Linear Colliders
Linear Colliders require high gradient (to reduce length dependent costs), high shunt impedance (to reduce power dependent costs) accelerator structures in which the long range dipole wakefields have been reduced by 2 to 3 orders of magnitude. The precise dipole wake reduction factor required depends on many factors. These include the beam intensity and time structure, the accelerator aperture and accelerating gradient, the strength of the focusing, the alignment precision and position stability of accelerator structures and the focusing elements, the effectiveness of the tuning procedure and feedback system, the pulse to pulse stability of the injected beam, and the required emittance at the final focus. For the purposes of this paper the authors accept that large reduction factors are required and discuss various approaches to achieving them. There are basically two approaches: detuning and damping, which are often used in combination. Damping can be accomplished either by introducing loss selectively into the accelerating structure cells, or by coupling the dipole modes out of the accelerating region and absorbing them in external loads or lossy materials. Detuning can greatly reduce the amount of damping required by causing the dipole modes to decohere, and it is possible to achieve destructive interferencemore » so that the wakefields from different cells in the accelerator cancel each other as seen by the bunches of electrons travelling through the linac. Several different approaches have achieved large reduction in the long-range dipole wakefields so that they pose no restriction on the length of the bunch trains which can be used for linear colliders.« less
17792873
Recent Ideas on Upgrading the SLAC Accelerator
In June 1971, the SLAC accelerator will have completed its first five years of operation. The machine has recently achieved records of energy (22.1 GeV), peak beam current (82 mA at a 1.6 ..mu..s pulse length) and average beam power (880 kW). The demand for major accelerator innovations and improvements is becoming increasingly strong. Some of the recent ideas on this subject are summarized. There are a variety of options, and these can be divided into three categories: (a) improvements and upgrading of the existing linac; (b) energy and duty cycle increases by means of beam storage in a recirculation scheme, and (c) various colliding beam devices. The first category includes increasing beam energy by addition of rf power or increasing duty cycle by modifying the modulators; it also includes an rf monochromatizer which could sharpen energy spectrum by a factor of 30. The second category involves a scheme which would increase beam energy by ''storing'' the electrons in a recirculator until they can be re-injected and reaccelerated by the accelerator a second time. The third category comprises the possibility of colliding the linac beam with the beams stored in the SLAC storage ring (SPEAR) or of colliding the linacmore » beam with itself.« less
17190416
Design of a High Yield Position Source
The Stanford Linear Collider (SLC) requires a positron source with a yield large enough to give equal number of positrons and electrons at the interaction point. In addition, the colliding positrons must have an emittance and bunch length similar to the electron beam. This report describes the design of a high yield positron source to give these characteristics. Reference 1 contains more details of the systems of the SLC and positron source. The overall positron production system in relation to the SLC is shown in Fig. 1. A single bunch of electrons of 33 GeV is extracted from the Linac at the two-thirds point by means of a fast kicker magnet and a pair of septum magnets. The extracted electron beam is transported into the positron vault where it is focused to a spot size of + or -0.6 mm at the target. Spoiler foils are placed in the extracted beam path to increase the emittance so that the spot size cannot be made so small that target damage would occur. Positrons are collected in a focusing solenoid system using an iron shaped solenoidal field of 1 Tesla at the target and a pulsed solenoidal field from a flux concentratormore » with a peak field of 5 Tesla. The positron beam emerging from the focusing solenoid system is accelerated to 200 MeV in a 1.5 meter high-gradient-accelerator of 50 MeV/meter and three 3.05 m standard accelerator sections. The positrons are contained in the accelerator aperture using a 0.5 Tesla solenoidal field in the beginning and quadrupole focusing in the final two standard accelerator sections. The positrons are then transported back to the beginning of the Linac for further acceleration to 1.2 GeV, whereupon they are sent to the positron damping ring. Later they are removed from the damping ring, accelerated to the end of the Linac, and transported around the e/sup +/ arc to the interaction point.« less