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Transfer of polarized 3He ions in the AtR beam transfer line

Description: In addition to collisions of electrons with various unpolarized ion species as well as polarized protons, the proposed electron-hadron collider (eRHIC) will facilitate the collisions of electrons with polarized {sup 3}He ions. The AGS is the last acceleration stage, before injection into one of the RHIC's collider ring for final acceleration. The AtR (AGS to RHIC) transfer line will be utilized to transport the polarized {sup 3}He ions from AGS into one of the RHIC's collider rings. Some of the… more
Date: May 20, 2012
Creator: Tsoupas, N.; MacKay, W. W.; Meot, F.; Roser, T. & Trbojevic, D.
Partner: UNT Libraries Government Documents Department
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The AGS with four helical magnets

Description: The idea of using multiple partial helical magnets was applied successfully to the AGS synchrotron, to preserve the proton beam polarization. In this paper we explore in details the idea of using four helical magnets placed symmetrically in the AGS ring. This modification provides many advantages over the present setup of the AGS that uses two partial helical magnets. First, it provides a larger 'spin tune gap' for the placement of the vertical betatron tune of the AGS during acceleration, seco… more
Date: February 25, 2010
Creator: Tsoupas, N.; Huang, H.; MacKay, W. W.; Roser, T. & Trbojevic, D.
Partner: UNT Libraries Government Documents Department
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Superconducting Non-Scaling Ffag Gantry for Carbon-Proton Cancer Therapy

Description: We report on improvements in the non-scaling Fixed Field Alternating Gradient (FFAG) gantry design. As we previously reported, a major challenge of the carbodproton cancer therapy facilities is isocentric gantry design. The weight of the isocentric gantry transport elements in the latest Heidelberg carbon/proton facility is 135 tons. In this report we detail improvements to the previous non-scaling gantry design. We estimate that this non-scaling FFAG gantry would be almost hundred times lighte… more
Date: June 25, 2007
Creator: Trbojevic, D.; Gupta, R.; Parker, B.; Keil, E. & Sessler, A. M.
Partner: UNT Libraries Government Documents Department
open access

1.5-GEV FFAG ACCELERATOR AS INJECTOR TO THE BNL-AGS.

Description: A 1.5-GeV Fixed-Field Alternating-Gradient (FFAG) proton Accelerator is being studied as a new injector to the Alternating-Gradient Synchrotron (AGS) of Brookhaven National Laboratory (BNL). The major benefit is that it would considerably shorten the overall AGS acceleration cycle, and, consequently, may yield to an improvement of beam stability, intensity and size. The AGS-FFAG will also facilitate the proposed upgrade of the AGS facility toward a 1-MW average proton beam power at the top ener… more
Date: July 5, 2004
Creator: Ruggiero, A. G.; Blaskiewicz, M.; Trbojevic, D.; Tsoupas, N. & Zhang, W.
Partner: UNT Libraries Government Documents Department
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Luminescence Beam Profile Monitor for the RHIC Polarized Hydrogen Jet Polarimeter.

Description: A new polarized hydrogen jet target was used to provide improved beam polarization measurements during the second polarized proton m in the Relativistic Heavy Ion Collider (RHIC). The luminescence produced by beam-hydrogen excitations was also used to test the feasibility of a new beam profile monitor for RFPIC based on the detection of the emitted light. Lenses, a view-port and a sensitive CCD camera were added to the system to record the optical signals from the interaction chamber. The first… more
Date: May 16, 2005
Creator: Luciano, N.; Nass, A.; Makdisi, Y.; Thieberger, P.; Trbojevic, D. & Zelenski, A.
Partner: UNT Libraries Government Documents Department
open access

The RHIC Hydrogen Jet Luminescence Monitor

Description: A hydrogen jet polarimeter was developed for the RHIC accelerator to improve the process of measuring polarization. Particle beams intersecting with gas molecules can produce light by the process known as luminescence. This light can then be focused, collected, and processed giving important information such as size, position, emittance, motion, and other parameters. The RHIC hydrogen jet polarimeter was modified in 2005 with specialized optics, vacuum windows, light transport, and a new camera… more
Date: June 25, 2007
Creator: Russo, T.; Bellavia, S.; Gassner, D.; Thieberger, P.; Trbojevic, D. & Tsang, T.
Partner: UNT Libraries Government Documents Department
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Applications of the RHIC AC Dipoles and Their Expected Performance

Description: Two AC dipoles with horizontal and vertical oscillating magnetic fields will be installed in RHIC. They will provide coherent oscillations for beam dynamic studies and betatron function measurements. The AC dipole with horizontal magnetic field will also be used to induce a full spin flip for RHIC polarized proton experiments. This note discusses the applications of the AC dipoles in RHIC and their expected parameters
Date: June 18, 1999
Creator: M., Bai; Parker, B.; Meth, M.; Peggs, S.; Roser, T. & Trbojevic, D.
Partner: UNT Libraries Government Documents Department
open access

Beam Lifetime Dependence on the Beam-Gas Interactions in RHIC.

Description: In the Relativistic Heavy ion Collider (RHIC) much larger background signals were occurring at BRAMS, one of the four experiments. This was especially pronounced at the time when vacuum conditions deteriorated due to the beam ionization profile monitor replacements. Recording the beam intensities during the store provided the beam lifetime. Predictions from the beam gas interactions to the above measured values are compared The ionization gauges simultaneously recorded the vacuum pressure data.
Date: June 18, 2001
Creator: Trbojevic, D.; Hsueh, H. C.; MacKay, W.; Drees, A. & Fliller, R.
Partner: UNT Libraries Government Documents Department
open access

RHIC susceptibility to variations in systematic magnetic harmonic errors

Description: Results of a study to determine the sensitivity of tune to uncertainties of the systematic magnetic harmonic errors in the 8 cm dipoles of RHIC are reported. Tolerances specified to the manufacturer for tooling and fabrication can result in systematic harmonics different from the expected values. Limits on the range of systematic harmonics have been established from magnet calculations, and the impact on tune from such harmonics has been established.
Date: August 1, 1994
Creator: Dell, G. F.; Peggs, S.; Pilat, F.; Satogata, T.; Tepikian, S.; Trbojevic, D. et al.
Partner: UNT Libraries Government Documents Department
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A study of betatron and momentum collimators in RHIC

Description: The Relativistic Heavy Ion Collider (RHIC) has two interaction regions where {beta}* = 1--2m, with large detectors PHENIX and STAR. The transverse and longitudinal emittances are expected to double in size between one to two hours due to intra-beam scattering which may lead to transverse beam loss. Primary betatron collimators are positioned in the ring to allow efficient removal of particles with large betatron amplitudes. The authors have investigated distributions and losses coming from the … more
Date: July 1, 1997
Creator: Trbojevic, D.; Stevens, A. J.; Harrison, M. A.; Dell, F. & Peggs, S.
Partner: UNT Libraries Government Documents Department
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Measurements of the betatron functions and phases in RHIC

Description: The Relativistic Heavy Ion Collider (RHIC) consists of two rings with six fold symmetry. The six interaction regions (IR)s are connected with twelve FODO cells. RHIC quadrupoles in the interaction regions have independent tuning capability. The betatron functions will be measured by a three methods. First, tunable IR quadrupoles will be adjusted to measure betatron functions at those locations through the change in tune. Second, sinusoidal coherent dipole oscillations will be used to measure th… more
Date: August 1, 1998
Creator: Trbojevic, D.; Kewisch, J.; Peggs, S.; Satogata, T.; Tepikian, S. & Goddere, G.
Partner: UNT Libraries Government Documents Department
open access

Beam Lifetime Dependence on the Beam-Gas Interactions in Rhic.

Description: In the Relativistic Heavy ion Collider (RHIC) much larger background signals were occurring at BRAMS, one of the four experiments. This was especially pronounced at the time when vacuum conditions deteriorated due to the beam ionization profile monitor replacements. Recording the beam intensities during the store provided the beam lifetime. Predictions from the beam gas interactions to the above measured values are compared The ionization gauges simultaneously recorded the vacuum pressure data.
Date: June 18, 2001
Creator: Trbojevic, D.; Hsueh, H. C.; MacKay, W. W.; Drees, A. & Fliller, R.
Partner: UNT Libraries Government Documents Department
open access

The Transverse Linac Optics Design in Multi-pass ERL

Description: In this paper, we analyzed the linac optics design requirement for a multi-pass energy recovery linac (ERL) for arbitrary number of linacs. A set of general formula of constrains for the 2-D transverse matrix is derived to ensure design optics acceptance matching throughout the entire accelerating and decelerating process. Meanwhile, the rest free parameters can be adjusted for fulfilling other requirements or optimization purpose. As an example, we design the linac optics for the future MeRHIC… more
Date: May 23, 2010
Creator: Hao, Y.; Kewisch, J.; Litvinenko,V.; Pozdeyev, E.; Ptitsyn, V.; Trbojevic, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Optimization of the Parameters in the RHIC Single Crystal Heavy Ion Collimation.

Description: In the framework of the project to design and test a collimation system prototype using bent channeling crystal for cleaning of the RHIC heavy ion beam halo, we have studied the optimal length and bending angle of a silicon (110) single crystal proposed to be a primary element situated upstream of the traditional heavy amorphous collimator. Besides the matters of the channeling and collimation efficiency, we also looked into the impact the crystal may have on the non-channeled particles that go… more
Date: March 29, 1999
Creator: Biryukov, v. M.; Chesnokov, Y. A.; Kotov, v. I.; Trbojevic, D. & Stevens, A.
Partner: UNT Libraries Government Documents Department
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