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Study report of the booster transition jump system

Description: There are more than 15 years since the transition-jump system (TJS) was installed. Because of the quad steering, which is caused by the beam not being well centered through all the {gamma}{sub T} quads, the TJS has never been used in the operation. Based upon the recent calculation, the short 12 {gamma}{sub T} quad had the worst offset in the vertical direction, and it was lowered 4 mm. Afterwards, the orbit error caused by the {gamma}{sub T} quad steering has been largely removed, and this encourages our efforts of commissioning the TJS to reach its design goal.
Date: December 1, 2004
Creator: Yang, Xi; Ankenbrandt, Charles M.; Pellico, William A. & Lackey, James
Partner: UNT Libraries Government Documents Department
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C0 Vibrational analysis

Description: This is an attempt to document some of the measurements and analysis relating to the modulation of the spill due to the vibration of the magnets in the new C0 area. Not all of the relevant graphs were saved at the time, however an attempt has been made to show representative illustrations albeit not in the proper chronological order.
Date: August 1, 1999
Creator: Moore, Craig D.; Johnson, Todd; Martens, Mike; Syphers, Mike; McCrory, E.; McGee, Mike et al.
Partner: UNT Libraries Government Documents Department
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Analysis of quench properties of the Q3 magnets with and without open circuit heater elements

Description: The Q3 magnets have 2 independent heater elements that are energized by the quench protection system. One heater element in the Q3 magnet at A4 became an open circuit after the initial cooldown. Recently the second element became an open circuit. The Q3 magnet at A4 is powered in series with a Q3 magnet at B1. The heaters in the magnet at B1 are still intact. The purpose of this study is to determine if the magnet circuit can be operated without undue risk of damage to the magnets. The risk of damage to the magnet at A4 is less of a concern since repairing the heaters is expected to be a major effort in any event. There is one spare Q3 magnet.
Date: November 1, 1995
Creator: Lackey, Sharon; Marriner, John & Pfeffer, Howie
Partner: UNT Libraries Government Documents Department
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Reducing the longitudinal emittance of the 8-GeV beam via the rf manipulation in a booster cycle

Description: Bunch rotation will cause the longitudinal emittance growth whenever there are far more A rf stations than B rf stations, or vice versa. An alternate method via optimizing the RFSUM curve in a Booster cycle has been investigated using the ESME simulation. Since the rf manipulation at transition crossing can reduce the longitudinal emittance 31% and the momentum spread 17%, eventually, the rms momentum spread of 2.98 MeV and the longitudinal emittance of 0.061 eV {center_dot} sec with 95% of the beam can be achieved at 8-GeV.
Date: August 1, 2005
Creator: Yang, Xi; Lebedev, Valeri A. & Ankenbrandt, Charles M.
Partner: UNT Libraries Government Documents Department
open access

Transverse coherent instability of a bunch in a rectangular potential well

Description: Theory of transverse instability of a bunch in a rectangular potential well is developed. Series of equations adequately describing the instability is derived and solved both analytically and numerically. Dependence of the instability increment and threshold on bunch factor is investigated for various beam coupling impedances. The theory is applied to the Fermilab Recycler Ring.
Date: April 1, 2006
Creator: Balbekov, V.
Partner: UNT Libraries Government Documents Department
open access

Dispersion in the Presence of Strong Transverse Wakefields

Description: To minimize emittance growth in a long linac, it is necessary to control the wakefields by correcting the beam orbit excursions. In addition, the particle energy is made to vary along the length of the bunch to introduce a damping, known as the BNS damping, to the beam break-up effect. In this paper, we use a two-particle model to examine the relative magnitudes of the various orbit and dispersion functions involved. The results are applied to calculate the effect of a closed orbit bump and a misaligned structure. It is shown that wake-induced dispersion is an important contribution to the beam dynamics in long linacs with strong wakefields like SLC.
Date: August 12, 2011
Creator: Assmann, Ralph & Chao, Alex
Partner: UNT Libraries Government Documents Department
open access

Geometrical Wake of a Smooth Flat Collimator

Description: A transverse geometrical wake generated by a beam passing through a smooth flat collimator with a gradually varying gap between the upper and lower walls is considered. Based on generalization of the approach recently developed for a smooth circular taper we reduce the electromagnetic problem of the impedance calculation to the solution of two much simpler static problems - a magnetostatic and an electrostatic ones. The solution shows that in the limit of not very large frequencies, the impedance increases with the ratio h/d where h is the width and d is the distance between the collimating jaws. Numerical results are presented for the NLC Post Linac collimator.
Date: September 9, 2011
Creator: Stupakov, G.V.
Partner: UNT Libraries Government Documents Department
open access

Proposed FNAL 750 KeV Linac Injector Upgrade

Description: The present FNAL linac H{sup -} injector has been operational since 1978 and consists of a magnetron H{sup -} source and a 750 keV Cockcroft-Walton Accelerator. The proposed upgrade to this injector is to replace the present magnetron source having a rectangular aperture with a circular aperture, and to replace the Cockcroft-Walton with a 200 MHz RFQ. Operational experience at other laboratories has shown that the upgraded source and RFQ will be more reliable and require less manpower than the present system.
Date: April 1, 2009
Creator: Tan, C. Y.; Bollinger, D. S. & Schmidt, C. W.
Partner: UNT Libraries Government Documents Department
open access

Theoretical study of proton beam preparation for the g-2 experiment

Description: Beam preparation for the g-2 experiment is studied. Because of limited 2.5-MHz rf voltage and the 66-ms limited time duration allowance for the whole process, the Booster batch must be first captured to a lower 2.5-MHz rf voltage followed by a rotation in the 2.5-MHz bucket in order to achieve the required narrow half bunch width of 50 ns. The appearance of bunch tails can be reduced by first rotation by a linear barrier voltage before the adiabatic capture.
Date: December 1, 2011
Creator: Ng, King-Yuen
Partner: UNT Libraries Government Documents Department
open access

A Conceptual Design of an Internal Injection Absorber of 8 GeV H-Injection into the Fermilab Main Injector

Description: An 8 GeV superconducting linear accelerator (SCL) has been proposed as a single stage H{sup -} injector into the Main Injector (MI) synchrotron[1]. This would be the highest energy H{sup -} multi-turn injection system in the world. An injection absorber is required to absorb a few percent o the incoming beam on a regular pulse by pulse basis. The requirements and conceptual design of an internal absorber, capable of steady state 6.5 kW is discussed.
Date: June 1, 2007
Creator: Johnson, D. E.; Chen, A.; Rakhno, I. & /Fermilab
Partner: UNT Libraries Government Documents Department
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SRF cavities for CW option of Project X Linac

Description: Alternative option of Project X is based on the CW SC 2GeV Linac with the average current 1mA. Possible option of the CW Linac considered in the paper includes low energy part consisted of a few families SC Spoke cavities (from 2.5 MeV to 466 MeV) and high energy part consisted of 2 types of elliptical cavities (v/c=0.81 and v/c=1). Requirements and designed parameters of cavities are considered.
Date: September 1, 2009
Creator: Solyak, N.; Gonin, I.; Khabiboulline, T.; Lunin, A.; Perunov, N. & Yakovlev, V.
Partner: UNT Libraries Government Documents Department
open access

Verification of the AWA Photoinjector Beam Parameters Required for a Transverse-to-Longitudinal Emittance Exchange Experiment

Description: A transverse-to-longitudinal emittance exchange experiment is in preparation at the Argonne Wakefield Accelerator (AWA). The experiment aims at exchanging a low ({var_epsilon}{sub z} < 5 {micro}m) longitudinal emittance with a large ({var_epsilon}{sub x} > 15 {micro}m) transverse horizontal emittance for a bunch charge of {approx}100 pC. Achieving such initial emittance partitioning, though demonstrated via numerical simulations, is a challenging task and needs to be experimentally verified. In this paper, we report preliminary emittance measurements of the beam in the transverse and longitudinal planes performed at {approx}12 MeV. The measurements are compared with numerical simulations.
Date: May 1, 2009
Creator: Rihaoui, M. M.; Piot, P.; Power, J. G.; Mihalcea, D. & Gai, W.
Partner: UNT Libraries Government Documents Department
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