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Correction of second order chromaticity at Tevatron

Description: Correction of the second order betatron tune chromaticity is essential for operation at the working point near half integer resonance which is proposed as one of the ways to improve performance of the Tevatron. In this report the new chromaticity correction scheme with split sextupole families is described. Details of implementation and commissioning at the present working point are discussed.
Date: June 1, 2007
Creator: Valishev, A.; Annala, G.; Lebedev, V.; Moore, R.S. & /Fermilab
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Partner: UNT Libraries Government Documents Department
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8 GeV beam line optics optimization for the rapid antiproton transfers at Fermilab

Description: Tevatron Run-II upgrade requires a significant increase of the efficiency and speed of the antiproton transfers from the Accumulator to the Recycler. The goal for the total transfer time is challenging a reduction from 1 hour down to a few minutes. Here we discuss the beam line optics aspects of this project. Results of lattice measurements and optimization are analyzed in terms of transport efficiency and stability.
Date: February 1, 2007
Creator: Nagaslaev, V.; Lebedev, V.; Morgan, J. & Vander Meulen, D.
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Partner: UNT Libraries Government Documents Department
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Instabilities of cooled antiproton beam in recycler

Description: The more beam is cooled, the less stable it is. In the 3.3 km Recycler Ring, stacked 8 GeV antiprotons are cooled both with stochastic (transversely) and electron (3D) cooling. Since the machine is staying near the coupling resonance, coupled optical functions should be used for stability analysis. To stabilize beam against the resistive wall instability, a digital damper is used. Digital dampers can be described as linear operators with explicit time dependence, and that makes a principle diff… more
Date: June 1, 2007
Creator: Burov, A. & Lebedev, V.
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Partner: UNT Libraries Government Documents Department
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Minimal interference beam size/profile measurement techniques applicable to the Collider

Description: The imaging of synchrotron radiation (SR) has been suggested as a technique for providing a continuous, non-interfering monitor of the beam profile in the Collider rings at the Superconducting Super Collider. A closer examination has raised questions concerning the applicability of SR imaging in this case because of the diffraction broadening of the image, the requirements for axial space and location in the lattice, and the complexity of the system. We have surveyed the known, alternative, min… more
Date: May 1, 1993
Creator: Nexsen, W.; Dutt, S.; Kauffmann, S.; Lebedev, V.; Maschke, A.; Mokhov, N. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Project X functional requirements specification

Description: Project X is a multi-megawatt proton facility being developed to support a world-leading program in Intensity Frontier physics at Fermilab. The facility is designed to support programs in elementary particle and nuclear physics, with possible applications to nuclear energy research. A Functional Requirements Specification has been developed in order to establish performance criteria for the Project X complex in support of these multiple missions, and to assure that the facility is designed with… more
Date: May 1, 2012
Creator: Holmes, S. D.; Henderson, S. D.; Kephart, R.; Kerby, J.; Kourbanis, I.; Lebedev, V. et al.
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Partner: UNT Libraries Government Documents Department
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Analysis of beam loss mechanism in the Project X linac

Description: Minimization of the beam losses in a multi-MW H{sup -} linac such as ProjectX to a level below 1 W/m is a challenging task. The impact of different mechanism of beam stripping, including stripping in electric and magnetic fields, residual gas, blackbody radiation and intra-beam stripping, is analyzed. Other sources of beam losses are misalignements of beamline elements and errors in RF fields and phases. We present in this paper requirements for dynamic errors and correction schemes to keep bea… more
Date: March 1, 2011
Creator: Carneiro, J. P.; Lebedev, V.; Nagaitsev, S.; Ostiguy, J. F. & Solyak, N.
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Partner: UNT Libraries Government Documents Department
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Progress with PXIE MEBT Chopper

Description: 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 5 mA, 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 t… more
Date: May 1, 2012
Creator: Lebedev, V.; Chen, A.; Pasquinelli, R; Peterson, D.; Saewert, G.; Shemyakin, A. et al.
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Partner: UNT Libraries Government Documents Department
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Status of the Project-X CW Linac Design

Description: Project-X is a proposed proton accelerator complex at Fermilab that would provide particle beams to support a diversified experimental program at the intensity frontier. As currently envisioned, the complex would employ a CW superconducting linac to accelerate a 1 mA average, 5 mA peak H{sup -} beam from 2.1 MeV to 3 GeV. A second superconducting linac, operating in pulsed mode would ultimately accelerate a small fraction of this beam up to 8 GeV. The CW linac is based on five families of reson… more
Date: May 1, 2012
Creator: Ostiguy, J. F.; Solyak, N.; Berrutti, P.; Carneiro, J. P.; Lebedev, V.; Nagaitsev, S. et al.
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Partner: UNT Libraries Government Documents Department
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Observation of Instabilities of Coherent Transverse Oscillations in the Fermilab Booster

Description: The Fermilab Booster - built more than 40 years ago - operates well above the design proton beam intensity of 4 {center_dot} 10{sup 12} ppp. Still, the Fermilab neutrino experiments call for even higher intensity exceeding 5.5 {center_dot} 10{sup 12} ppp. A multitude of intensity related effects must be overcome in order to meet this goal including suppression of coherent dipole instabilities of transverse oscillations which manifest themselves as a sudden drop in the beam current. In this repo… more
Date: May 1, 2012
Creator: Alexahin, Y.; Eddy, N.; Gianfelice-Wendt, E.; Lebedev, V.; Marsh, W.; Pellico, W. et al.
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Partner: UNT Libraries Government Documents Department
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Measurement and correction of the 3rd order resonance in the Tevatron

Description: At Fermilab Tevatron BPM system has been recently upgraded resulting much better accuracy of beam position measurements and improvements of data acquisition for turn-by-turn measurements. That allows one to record the beam position at each turn for 8000 turns for all BPMs (118 in each plane) with accuracy of about 10-20 {micro}m. In the last decade a harmonic analysis tool has been developed at CERN that allows relating each FFT line derived from the BPM data with a particular non-linear resona… more
Date: June 1, 2006
Creator: Schmidt, F.; Alexahin, Y.; Lebedev, V.; Still, D. & Valishev, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement and optimization of the lattice functions in the debuncher ring at Fermilab

Description: Tevatron Run-II upgrade requires substantial increase of antiproton production. The central step towards this goal is maximizing the Debuncher ring admittance which necessitates detailed understanding of the Debuncher optics and aperture limitations. The method of the response matrix optimization has been used to determine quadrupole errors and to build a model of machine optics. We estimate that the model predicts beta-functions with accuracy of about 5% mainly limited by Beam Position Monitor… more
Date: June 1, 2006
Creator: Nagaslaev, V.; Gollwitzer, K.; Lebedev, V.; Valishev, A. & Sajaev, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Progress with collision optics of the Fermilab Tevatron collider

Description: Recent advances in the measurement and modeling of the machine parameters and lattice functions at the Tevatron allowed modifications of the collision optics to be performed in order to increase the collider luminosity. As the result, beta functions in the two collision points were decreased from 35cm to 29cm which resulted in {approx}10% increase of the peak luminosity. In this report we describe the results of optics measurements and corrections. We also discuss planned improvements, includin… more
Date: June 1, 2006
Creator: Valishev, A.; Alexahin, Y.; Annala, J.; Lebedev, V.; Nagaslaev, V. & Sajaev, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Optical transition radiation interferometry for A0 photoinjector

Description: A charged particle passing through the boundary of two medias with different permittivity values generates Transition Radiation (TR), [1]. The TR is caused by a variation of the particle electric field with variation of the permittivity. The TR for relativistic particles has a wide spectrum with a significant portion in the optical range. The Optical Transition Radiation (OTR) is widely used for a beam profile monitoring and measurements of a beam size. Moreover, OTR can be used to characterize… more
Date: March 1, 2007
Creator: Kazakevich, G.; Edwards, H.; Fliller, R.; Lebedev, V.; Nagaitsev, S.; Santucci, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Coherent instabilities at the FNAL Booster

Description: This paper presents results of experimental and theoretical investigations of transverse beam stability at injection to Fermilab Booster and discusses a novel scheme for transition crossing allowing to avoid the longitudinal emittance growth related to the transition. At reduced chromaticity a multibunch high order head-tail mode develops with growth time of 12 turns at fractional part of tune close to zero. An estimate of the growth rate based on known sources of impedance results in significa… more
Date: June 1, 2006
Creator: Lebedev, V.; Burov, A.; Pellico, W.; Yang, X. & /Fermilab
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Suppression of transverse instability by a digital damper

Description: With cooling, beam phase space density increases, which makes the beam motion intrinsically unstable. To suppress instabilities, dampers are required. With a progress of digital technology, digital dampers are getting to be more and more preferable. Conversion of an analog signal into digital one is described by a linear operator with explicit time dependence. Thus, the analog-digital converter (ADC) does not preserve a signal frequency. Instead, a monochromatic input signal is transformed into… more
Date: June 1, 2006
Creator: Burov, A. & Lebedev, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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OTR interferometry diagnostic for the A0 photoinjector

Description: OTR interferometry (OTRI) is an attractive diagnostic for investigation of relativistic electron beam parameters. The diagnostic is currently under development at the A0 Photoinjector. This diagnostic is also applicable for NML accelerator test facility that will be built at Fermilab. The experimental setup of the OTR Interferometer for the FNAL A0 Photoinjector is described in the report. Results of simulations and measurements are presented and discussed.
Date: June 1, 2007
Creator: Kazakevich, G.; Edwards, Helen Thom; Fliller, R.; Lebedev, V.; Nagaitsev, S. & Thurman-Keup, R.
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Partner: UNT Libraries Government Documents Department
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Coherent synchro-betatron resonance

Description: Coherent synchro-betatron resonances can present a serious limit for low-energy synchrotrons with strong space charge. Here, an excitation of a dipole transverse mode is considered at resonance condition.
Date: December 1, 2006
Creator: Burov, A. & Lebedev, V.
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Partner: UNT Libraries Government Documents Department
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Measurement and correction of linear optics and coupling at tevatron complex

Description: The optics measurements have played important role in improving the performance of Tevatron collider. Until recently, most of them were based on the differential orbit measurements with data analysis, which neglects measurement inaccuracies such as differences in differential responses of beam position monitors, their rolls, etc. To address these complications we have used a method based on the analysis of many differential orbits. That creates the redundancy in the data allowing to get more de… more
Date: January 1, 2006
Creator: Lebedev, V.; Nagaslaev, V.; Valishev, A. & Sajaev, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Production and Collections of Antiprotons

Description: The historical best antiproton yield obtained at the antiproton source is equal to 1.8 {center_dot} 10{sup -5}. That corresponds to the acceptance of about 17 mm {center_dot} mrad while the largest measured debuncher acceptance is about 25 mm {center_dot} mrad. It is expected that better debuncher tuning will increase the debuncher acceptance to about 35 mm {center_dot} mrad. Thus, improvements of optics and steering in the AP2 line and debuncher should allow an increase of antiproton yield by … more
Date: January 1, 2001
Creator: Lebedev, V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Intrabeam stripping in H- Linacs

Description: A beam loss in the superconducting part of the SNS linac has been observed during its commissioning and operation. Although the loss does not prevent the SNS high power operation, it results in an almost uniform irradiation of linac components and increased radiation levels in the tunnel. Multi-particle tracking could neither account for the magnitude of the observed loss nor its dependence on machine parameters. It was recently found that the loss is consistent with the intrabeam particle coll… more
Date: September 1, 2010
Creator: Lebedev, V.; Solyak, N.; Ostigy, J. -F.; Alexandrov, A. & Shishlo, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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