355 research outputs found
Summary of Fermilab's Recycler Electron Cooler Operation and Studies
Fermilab's Recycler ring was used as a storage ring for accumulation and
subsequent manipulations of 8-GeV antiprotons destined for the Tevatron
collider. To satisfy these missions, a unique electron cooling system was
designed, developed and successfully implemented. The most important features
that distinguish the Recycler cooler from other existing electron coolers are
its relativistic energy (it employs a 4.3 MeV, 0.1 A DC electron beam), a weak
continuous longitudinal magnetic field in the cooling section (~100 G), and
lumped focusing elsewhere. With the termination of the collider operation at
Fermilab, the cooler operation was also terminated. In this article, we will
summarize the experience of commissioning, optimizing and running this unique
machine over the 6 years of its existence.Comment: 3 pp. 3rd International Particle Accelerator Conference (IPAC 2012)
20-25 May 2012. New Orleans, Louisian
Progress with PXIE MEBT Chopper
A capability to provide a large variety of bunch patterns is crucial for the
concept of the Project X serving MW-range beam to several experiments
simultaneously. This capability will be realized by the Medium Energy Beam
Transport's (MEBT) chopping system that will divert 80% of all bunches of the
initially 5mA, 2.1 MeV CW 162.5 MHz beam to an absorber according to a
pre-programmed bunch-by-bunch selection. Being considered one of the most
challenging components, the chopping system will be tested at the Project X
Injector Experiment (PXIE) facility that will be built at Fermilab as a
prototype of the Project X front end. The bunch deflection will be made by two
identical sets of travelling-wave kickers working in sync. Currently, two
versions of the kickers are being investigated: a helical 200 Ohm structure
with a switching-type 500 V driver and a planar 50 Ohm structure with a linear
250 V amplifier. This paper will describe the chopping system scheme and
functional specifications for the kickers, present results of electromagnetic
measurements of the models, discuss possible driver schemes, and show a
conceptual mechanical design.Comment: 3 pp. 3rd International Particle Accelerator Conference (IPAC 2012)
20-25 May 2012. New Orleans, Louisian
"Hollow cathode" gun optics
The generation of an electron beam by a hollow cathode gun in a cusp magnetic field is discussed. Such a gun is proposed for an electron cooling device without toroids. In a section with a homogeneous magnetic field, this beam experiences a disturbance region near the axis where the electron temperature becomes higher. The main purpose of the article is to define conditions for generating the beam so as to restrict the extent of this region as much as possible. It is shown that a state with a virtual cathode in the vicinity of the zero magnetic field point is the most suitable for this aim. The experimental and essential analytical results are presented
Research of impact input rate random variations on macroscopic characteristics of non-stationary queuing system
The results of research of input stream rate random variations influence on the macroscopic characteristics of a nonstationary queuing system (NQS) are discussed in this paper. Statistical information obtained during the football match between the football clubs "Krylia Sovetov" and "Dynamo" at the stadium "Metallurg" in Samara is available. The characteristics of the stochastic component of the variation in the input rate were chosen on the basis of this information. The probability density function and the cumulative distribution function of random variations in the input rate of applications were estimated using the Rosenblatt-Parzen approximation. NQ's characteristics was studied such as the maximum queue length, the maximum waiting time in the queue, the time point at which the maximum queue length is reached, and the time point at which waiting time in the queue the longest, the number of visitors who entered at the time of the match beginning, the time needed to service the entire queue. The results of the statistical simulation shown that taking into account the random component of the variation input rate does not affect this macroscopic characteristics. Β© Published under licence by IOP Publishing Ltd
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