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The X(3872) boson: Molecule or charmonium

Description: It has been argued that the mystery boson X(3872) is a molecular state consisting of primarily D{sup 0}{bar D}*{sup 0} + {bar D}{sup 0}D*{sup 0}. In contrast, apparent puzzles and potential difficulties have been pointed out for the charmonium assignment of X(3872). They examine several aspects of these alternatives by semi-quantitative methods since quantitatively accurate results are often hard to reach on them. they point out that some of the observed properties of X(3872), in particular, the binding and the production rates are incompatible with the molecule interpretation. Despite puzzles and obstacles, X(3872) may fit more likely to the excited {sup 3}P{sub 1} charmonium than to the molecule after the mixing of c{bar c} with D{bar D}* + {bar D}D* is taken into account.
Date: August 1, 2005
Creator: Suzuki, Mahiko
Partner: UNT Libraries Government Documents Department

The CKM matrix and CP violation

Description: The status of CP violation and the CKM matrix is reviewed. Direct CP violation in B decay has been established and the measurement of sin 2{beta} in {psi}K modes reached 5% accuracy. I discuss the implications of these, and of the possible deviations of the CP asymmetries in b {yields} s modes from that in {psi}K. The first meaningful measurements of {alpha} and {gamma} are explained, together with their significance for constraining both the SM and new physics in B-{bar B} mixing. I also discuss implications of recent developments in the theory of nonleptonic decays for B {yields} {pi}K rates and CP asymmetries, and for the polarization in charmless B decays to two vector mesons.
Date: September 14, 2004
Creator: Ligeti, Zoltan
Partner: UNT Libraries Government Documents Department

CPT Tests: Kaon vs neutrinos

Description: CPT violation has an impressive limit in the neutral kaon system |m(K{sup 0})-m({bar K}{sup 0})| < 10{sup -18} m{sub K} = 0.50 x 10{sup -18} GeV. However, if viewed as a constraint on the mass-squared, the bound appears weak, |m{sup 2}(K{sup 0})-m{sup 2}({bar K}{sup 0})| < 0.25 eV{sup 2}. the authors point out that neutrino oscillation offers better limits on CPT violation in this case. The comparison of solar and rector neutrino results puts the best limit on CPT violation by far, |{Delta}m{sub {nu}}{sup 2}-{Delta}m{sub {rho}}{sup 2}| < 1.3 x 10{sup -3} eV{sup 2} (90% CL).
Date: July 9, 2003
Creator: Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department

Further results about field theory on the world sheet and stringformation

Description: The present article is the continuation of the earlier work, which used the world sheet representation and the mean field approximation to sum planar graphs in massless {phi}{sup 3} field theory. The authors improve on the previous work in two respects: A prefactor in the world sheet propagator that had been neglected is now taken into account. In addition, they introduce a non-zero bare mass for the field {phi}. Working with a theory with cutoff and using the mean field approximation, they find that, depending on the range of values of the mass and coupling constant, the model has two phases: A string forming phase and a perturbative field theory phase. They also find the generation of a new degree of freedom, which was not in the model originally. This new degree of freedom can be thought of as the string slope, which is now promoted into a fluctuating dynamical variable. Finally, they show that the introduction of the bare mass makes it possible to renormalize the model.
Date: January 15, 2005
Creator: Bardakci, Korbut
Partner: UNT Libraries Government Documents Department

PEP-II Transverse Feedback Electronics Upgrade

Description: The PEP-II B Factory at the Stanford Linear Accelerator Center (SLAC) requires an upgrade of the transverse feedback system electronics. The new electronics require 12-bit resolution and a minimum sampling rate of 238 Msps. A Field Programmable Gate Array (FPGA) is used to implement the feedback algorithm. The FPGA also contains an embedded PowerPC 405 (PPC-405) processor to run control system interface software for data retrieval, diagnostics, and system monitoring. The design of this system is based on the Xilinx(R) ML300 Development Platform, a circuit board set containing an FPGA with an embedded processor, a large memory bank, and other peripherals. This paper discusses the design of a digital feedback system based on an FPGA with an embedded processor. Discussion will include specifications, component selection, and integration with the ML300 design.
Date: May 9, 2005
Creator: Weber, J.; Chin, M.; Doolittle, L. & Akre, R.
Partner: UNT Libraries Government Documents Department

Optimal Extraction of Cosmological Information from Supernova Datain the Presence of Calibration Uncertainties

Description: We present a new technique to extract the cosmological information from high-redshift supernova data in the presence of calibration errors and extinction due to dust. While in the traditional technique the distance modulus of each supernova is determined separately, in our approach we determine all distance moduli at once, in a process that achieves a significant degree of self-calibration. The result is a much reduced sensitivity of the cosmological parameters to the calibration uncertainties. As an example, for a strawman mission similar to that outlined in the SNAP satellite proposal, the increased precision obtained with the new approach is roughly equivalent to a factor of five decrease in the calibration uncertainty.
Date: September 26, 2005
Creator: Kim, Alex G. & Miquel, Ramon
Partner: UNT Libraries Government Documents Department

A 3d Parallel Beam Dynamics Code for Modeling High BrightnessBeams in Photoinjectors

Description: In this paper we report on IMPACT-T, a 3D beam dynamics code for modeling high brightness beams in photoinjectors and rf linacs. IMPACT-T is one of the few codes used in the photoinjector community that has a parallel implementation, making it very useful for high statistics simulations of beam halos and beam diagnostics. It has a comprehensive set of beamline elements, and furthermore allows arbitrary overlap of their fields. It is unique in its use of space-charge solvers based on an integrated Green function to efficiently and accurately treat beams with large aspect ratio, and a shifted Green function to efficiently treat image charge effects of a cathode. It is also unique in its inclusion of energy binning in the space-charge calculation to model beams with large energy spread. Together, all these features make IMPACT-T a powerful and versatile tool for modeling beams in photoinjectors and other systems. In this paper we describe the code features and present results of IMPACT-T simulations of the LCLS photoinjectors. We also include a comparison of IMPACT-T and PARMELA results.
Date: May 16, 2005
Creator: Qiang, J.; Lidia, S.; Ryne, R. & Limborg, C.
Partner: UNT Libraries Government Documents Department

GUT breaking on the brane?

Description: We present a five-dimensional supersymmetric SU(5) theory in which the gauge symmetry is broken maximally (i.e. at the 5D Planck scale M{sub *}) on the same 4D brane where chiral matter is localized. Masses of the lightest Kaluza-Klein modes for the colored Higgs and X and Y gauge fields are determined by the compactification scale of the fifth dimension, M{sub C} {approx} 10{sup 15} GeV, rather than by M{sub *}. These fields' wave functions are repelled from the GUT-breaking brane, so that proton decay rates are suppressed below experimental limits. Above the compactification scale, the differences between the standard model gauge couplings evolve logarithmically, so that ordinary logarithmic gauge coupling unification is preserved. The maximal breaking of the grand unified group can also lead to other effects, such as O(1) deviations from SU(5) predictions of Yukawa couplings, even in models utilizing the Froggatt-Nielsen mechanism.
Date: April 4, 2001
Creator: Smith, David; Nomura, Yasunori & Weiner, Neal
Partner: UNT Libraries Government Documents Department

Transient beam loading in the ALS harmonic RF system

Description: We report on the commissioning of a higher harmonicradiofrequency system at the Advanced Light Source, designed to improvethe beam lifetime. We have achieved an increase above a factor of two inour best results up to now. Transient beam loading of the harmoniccavities, due to the unequal fill patterns, creates the greatestlimitation on lifetime improvement. We also describe several interestingeffects on the operation of the longitudinal and transverse multibunchfeedback system.
Date: June 1, 2000
Creator: Byrd, J.; De Santis, S.; Georgsson, M.; Stover, G.; Fox, J.; Prabhakar, S. et al.
Partner: UNT Libraries Government Documents Department

Studies of E-Cloud Build up for the FNAL Main Injector and for theLHC

Description: We present a summary of recent simulation studies of the electron-cloud (EC) build-up for the FNAL MI and for the LHC. In the first case we pay particular attention to the dependence on bunch intensity N{sub b} at injection energy assuming the nominal bunch spacing t{sub b} = 19 ns, and we focus on the dipole magnets and field-free regions. The saturated value of the average EC density shows a clear threshold in N{sub b} beyond which the beam will be approximately neutralized on average. For the case of the LHC we limit our discussion to arc dipoles at collision energy, and bunch spacings t{sub b} = 25 ns or t{sub b} = 75 ns. The main variables exercised in this study are N{sub b} and the peak value of the secondary emission yield (SEY) {delta}{sub max}. For t{sub b} = 25 ns we conclude that the EC power deposition is comfortably below the available cooling capacity of the cryogenic system if {delta}{sub max} is below {approx} 1.2 at nominal N{sub b}. For t{sub b} = 75 ns, the EC power deposition is insignificant. As a byproduct of this exercise, we reach a detailed understanding of the significant role played by the backscattered secondary electrons. This article summarizes the results, an slightly extends the discussions, presented in Refs. 1 and 2.
Date: June 14, 2006
Creator: Furman, M.A.
Partner: UNT Libraries Government Documents Department

A general scaling relation for the critical current density inNb3Sn

Description: We review the scaling relations for the critical currentdensity (Jc) in Nb3Sn wires and include recent findings on the variationof the upper critical field (Hc2) with temperature (T) and A15composition. Measurements of Hc2(T) in inevitably inhomogeneous wires, aswell as analysis of literature results, have shown that all availableHc2(T) data can be accurately described by a single relation from themicroscopic theory. This relation also holds for inhomogeneity averaged,effective, Hc2*(T) results and can be approximated by Hc2(t)=Hc2(0) =1-t1.52, with t = T=Tc.Knowing Hc2*(T) implies that also Jc(T) is known.We highlight deficiencies in the Summers/Ekin relations, which are notable to account for the correct Jc(T) dependence. Available Jc(H) resultsindicate that the magnetic field dependence for all wires from mu0H = 1 Tup to about 80 percent of the maximum Hc2 can be described with Kramer'sflux shear model, if non-linearities in Kramer plots when approaching themaximum Hc2 are attributed to A15 inhomogeneities. The strain (e)dependence is introduced through a temperature and strain dependentHc2*(T,e) and Ginzburg-Landau parameter kappa1(T,e) and a straindependent critical temperature Tc(e). This is more consistent than theusual Ekin unification of strain and temperature dependence, which usestwo separate and different dependencies on Hc2*(T) and Hc2*(e). Using acorrect temperature dependence and accounting for the A15 inhomogeneitiesleads to the remarkable simple relation Jc(H,T,e)=(C/mu0H)s(e)(1-t1.52)(1-t2)h0.5(1-h)2, where C is a constant, s(e)represents the normalized strain dependence of Hc2*(0) andh =H/Hc2*(T,e). Finally, a new relation for s(e) is proposed, which is anasymmetric version of our earlier deviatoric strain model and based onthe first, second and third strain invariants. The new scaling relationsolves a number of much debated issues withrespect to Jc scaling in Nb3Snand is therefore of importance to the applied community, who use scalingrelations to analyze magnet performance from wire results.
Date: May 8, 2006
Creator: Godeke, A.; Haken, B. ten; Kate, H.H.J. ten & Larbalestier, D.C.
Partner: UNT Libraries Government Documents Department

A general scaling relation for the critical current density inNb3Sn

Description: We review the scaling relations for the critical currentdensity (Jc) in Nb3Sn wires and include recent findings on the variationof the upper critical field (Hc2) with temperature (T) and A15composition. Measurements of Hc2(T) in inevitably inhomogeneous wires, aswell as analysis of literature results, have shown that all availableHc2(T) data can be accurately described by a single relation from themicroscopic theory. This relation also holds for inhomogeneity averaged,effective, Hc2*(T) results and can be approximated by Hc2(t)=Hc2(0) =1-t1.52, with t = T=Tc.Knowing Hc2*(T) implies that also Jc(T) is known.We highlight deficiencies in the Summers/Ekin relations, which are notable to account for the correct Jc(T) dependence. Available Jc(H) resultsindicate that the magnetic field dependence for all wires from mu0H = 1 Tup to about 80 percent of the maximum Hc2 can be described with Kramer'sflux shear model, if non-linearities in Kramer plots when approaching themaximum Hc2 are attributed to A15 inhomogeneities. The strain (e)dependence is introduced through a temperature and strain dependentHc2*(T,e) and Ginzburg-Landau parameter kappa1(T,e) and a straindependent critical temperature Tc(e). This is more consistent than theusual Ekin unification of strain and temperature dependence, which usestwo separate and different dependencies on Hc2*(T) and Hc2*(e). Using acorrect temperature dependence and accounting for the A15 inhomogeneitiesleads to the remarkable simple relation Jc(H,T,e)=(C/mu0H)s(e)(1-t1.52)(1-t2)h0.5(1-h)2, where C is a constant, s(e)represents the normalized strain dependence of Hc2*(0) andh =H/Hc2*(T,e). Finally, a new relation for s(e) is proposed, which is anasymmetric version of our earlier deviatoric strain model and based onthe first, second and third strain invariants. The new scaling relationsolves a number of much debated issues withrespect to Jc scaling in Nb3Snand is therefore of importance to the applied community, who use scalingrelations to analyze magnet performance from wire results.
Date: May 8, 2006
Creator: Godeke, A.; Haken, B. ten; Kate, H.H.J. ten & Larbalestier, D.C.
Partner: UNT Libraries Government Documents Department

Neutrino telescopes as a direct probe of supersymmetrybreaking

Description: We consider supersymmetric models where the scale of supersymmetry breaking lies between 5 x 10{sup 6} GeV and 5 x 10{sup 8} GeV. In this class of theories, which includes models of gauge mediated supersymmetry breaking, the lightest supersymmetric particle is the gravitino. The next to lightest supersymmetric particle is typically a long lived charged slepton with a lifetime between a microsecond and a second, depending on its mass. Collisions of high energy neutrinos with nucleons in the earth can result in the production of a pair of these sleptons. Their very high boost means they typically decay outside the earth. We investigate the production of these particles by the diffuse flux of high energy neutrinos, and the potential for their observation in large ice or water Cerenkov detectors. The relatively small cross-section for the production of supersymmetric particles is partially compensated for by the very long range of heavy particles. The signal in the detector consists of two parallel charged tracks emerging from the earth about 100 meters apart, with very little background. A detailed calculation using the Waxman-Bahcall limit on the neutrino flux and realistic spectra shows that km{sup 3} experiments could see as many as 4 events a year. We conclude that neutrino telescopes will complement collider searches in the determination of the supersymmetry breaking scale, and may even give the first evidence for supersymmetry at the weak scale.
Date: December 15, 2003
Creator: Albuquerque, Ivone; Burdman, Gustavo & Chacko, Z.
Partner: UNT Libraries Government Documents Department

Robust autoresonant excitation in the plasma beat-waveaccelerator: A theoretical study

Description: A modified version of the Plasma Beat-Wave Accelerator scheme is introduced and analyzed, which is based on autoresonant phase-locking of the nonlinear Langmuir wave to the slowly chirped beat frequency of the driving lasers via adiabatic passage through resonance. This new scheme is designed to overcome some of the well-known limitations of previous approaches, namely relativistic detuning and nonlinear modulation or other non-uniformity or non-stationarity in the driven Langmuir wave amplitude, and sensitivity to frequency mismatch due to measurement uncertainties and density fluctuations and inhomogeneities. As in previous schemes, modulational instabilities of the ionic background ultimately limit the useful interaction time, but nevertheless peak electric fields at or approaching the wave-breaking limit seem readily attainable. Compared to traditional approaches, the autoresonant scheme achieves larger accelerating electric fields for given laser intensity, or comparable fields for less laser power; the plasma wave excitation is much more robust to variations or uncertainties in plasma density; it is largely insensitive to the precise choice of chirp rate, provided only that chirping is sufficiently slow; and the quality and uniformity of the resulting plasma wave and its suitability for accelerator applications may be superior. In underdense plasmas, the total frequency shift required is only of the order of a few percent of the laser carrier frequency, and for possible experimental proofs-of-principle, the scheme might be implemented with relatively little additional modification to existing systems based on either solid-state amplifiers and Chirped Pulse Amplification techniques, or, with somewhat greater technological effort, using a CO{sub 2} or other gas laser system.
Date: November 3, 2004
Creator: Lindberg, R.R.; Charman, A.E. & Wurtele, J.S.
Partner: UNT Libraries Government Documents Department

Aperture studies for the Fermilab AP2 anti-proton line

Description: The AP2 beamline transports anti-protons from the production target to the Debuncher ring. The observed aperture is smaller than that estimated from linear, on-energy optics. We have investigated possible reasons for the aperture limitation and have identified possible sources,including residual vertical dispersion from alignment errors and chromatic effects due to very large chromatic lattice functions. Some experiments have already been performed to study these effects. We present results of the experimental and theoretical studies and possible remedies.
Date: June 23, 2004
Creator: Reichel, Ina; Placidi, Massimo; Zisman, Mike; Gollwitzer, Keith & Werkema, Steve
Partner: UNT Libraries Government Documents Department

Gauge unification in higher dimensions

Description: A complete 5-dimensional SU(5) unified theory is constructed which, on compactification on the orbifold with two different Z{sub 2}'s (Z{sub 2} and Z{sub 2}{prime}), yields the minimal supersymmetric standard model. The orbifold accomplishes SU(5) gauge symmetry breaking, doublet-triplet splitting, and a vanishing of proton decay from operators of dimension 5. Until 4d supersymmetry is broken, all proton decay from dimension 4 and dimension 5 operators is forced to vanish by an exact U(1){sub R} symmetry. Quarks and leptons and their Yukawa interactions are located at the Z{sub 2} orbifold fixed points, where SU(5) is unbroken. A new mechanism for introducing SU(5) breaking into the quark and lepton masses is introduced, which originates from the SU(5) violation in the zero-mode structure of bulk multiplets. Even though SU(5) is absent at the Z{sub 2}{prime} orbifold fixed point, the brane threshold corrections to gauge coupling unification are argued to be negligibly small, while the logarithmic corrections are small and in a direction which improves the agreement with the experimental measurements of the gauge couplings. Furthermore, the X gauge boson mass is lowered, so that p {yields} e{sup +}{pi}{sup 0} is expected with a rate within about one order of magnitude of the current limit. Supersymmetry breaking occurs on the Z{sub 2}{prime} orbifold fixed point, and is felt directly by the gauge and Higgs sectors, while squarks and sleptons acquire mass via gaugino mediation, solving the supersymmetric flavor problem.
Date: January 14, 2001
Creator: Hall, Lawrence & Nomura, Yasunori
Partner: UNT Libraries Government Documents Department

Analysis of KEK-ATF optics and coupling using LOCO

Description: LOCO is a computer code for analysis of the linear optics in a storage ring based on the closed orbit response to steering magnets. The analysis provides information on focusing errors, BPM gain and rotation errors, and local coupling. Here, we discuss the details of the LOCO implementation at the KEK-ATF Damping Ring, and report the initial results. Some of the information obtained, for example on the BPM gain and coupling errors, has not previously been determined. We discuss the possibility of using the data provided by the LOCO analysis to reduce the vertical emittance of the ATF beam.
Date: June 30, 2004
Creator: Wolski, Andrzej; Woodley, Mark D.; Nelson, Janice & Ross, Marc C.
Partner: UNT Libraries Government Documents Department

Wavelet-based Poisson Solver for use in Particle-In-CellSimulations

Description: We report on a successful implementation of a wavelet based Poisson solver for use in 3D particle-in-cell (PIC) simulations. One new aspect of our algorithm is its ability to treat the general(inhomogeneous) Dirichlet boundary conditions (BCs). The solver harnesses advantages afforded by the wavelet formulation, such as sparsity of operators and data sets, existence of effective preconditioners, and the ability simultaneously to remove numerical noise and further compress relevant data sets. Having tested our method as a stand-alone solver on two model problems, we merged it into IMPACT-T to obtain a fully functional serial PIC code. We present and discuss preliminary results of application of the new code to the modeling of the Fermilab/NICADD and AES/JLab photoinjectors.
Date: May 13, 2005
Creator: Terzic, B.; Mihalcea, D.; Bohn, C.L. & Pogorelov, I.V.
Partner: UNT Libraries Government Documents Department

Acceleressence: Dark energy from a phase transition at the seesawscale

Description: Simple models are constructed for ''acceleressence'' dark energy: the latent heat of a phase transition occurring in a hidden sector governed by the seesaw mass scale v{sup 2}/M{sub Pl}, where v is the electroweak scale and M{sub Pl} the gravitational mass scale. In our models, the seesaw scale is stabilized by supersymmetry, implying that the LHC must discover superpartners with a spectrum that reflects a low scale of fundamental supersymmetry breaking. Newtonian gravity may be modified by effects arising from the exchange of fields in the acceleressence sector whose Compton wavelengths are typically of order the millimeter scale. There are two classes of models. In the first class the universe is presently in a metastable vacuum and will continue to inflate until tunneling processes eventually induce a first order transition. In the simplest such model, the range of the new force is bounded to be larger than 25 {micro}m in the absence of fine-tuning of parameters, and for couplings of order unity it is expected to be {approx} 100 {micro}m. In the second class of models thermal effects maintain the present vacuum energy of the universe, but on further cooling, the universe will ''soon'' smoothly relax to a matter dominated era. In this case, the range of the new force is also expected to be of order the millimeter scale or larger, although its strength is uncertain. A firm prediction of this class of models is the existence of additional energy density in radiation at the eV era, which can potentially be probed in precision measurements of the cosmic microwave background. An interesting possibility is that the transition towards a matter dominated era has occurred in the very recent past, with the consequence that the universe is currently decelerating.
Date: October 5, 2004
Creator: Chacko, Z.; Hall, Lawrence J. & Nomura, Yasunori
Partner: UNT Libraries Government Documents Department

Solving the SUSY CP problem with flavor breaking F-terms

Description: Supersymmetric flavor models for the radiative generation of fermion masses offer an alternative way to solve the SUSY-CP problem. We assume that the supersymmetric theory is flavor and CP conserving. CP violating phases are associated to the vacuum expectation values of flavor violating susy-breaking fields. As a consequence, phases appear at tree level only in the soft supersymmetry breaking matrices. Using a U(2) flavor model as an example we show that it is possible to generate radiatively the first and second generation of quark masses and mixings as well as the CKM CP phase. The one-loop supersymmetric contributions to EDMs are automatically zero since all the relevant parameters in the lagrangian are flavor conserving and as a consequence real. The size of the flavor and CP mixing in the susy breaking sector is mostly determined by the fermion mass ratios and CKM elements. We calculate the contributions to {epsilon}, {epsilon}' and to the CP asymmetries in the B decays to {psi}K{sub s}, {phi}K{sub s}, {eta}'K{sub s} and X{sub s}{gamma}. We analyze a case study with maximal predictivity in the fermion sector. For this worst case scenario the measurements of {Delta}m{sub K}, {Delta}m{sub B} and {epsilon} constrain the model requiring extremely heavy squark spectra.
Date: May 11, 2005
Creator: Diaz-Cruz, Lorenzo J. & Ferrandis, Javier
Partner: UNT Libraries Government Documents Department

Universality and mX cut effects in B ->Xsl+l-

Description: The most precise comparison between theory and experiment for the B {yields} X{sub s}{ell}{sup +}{ell}{sup -} rate is in the q{sup 2} < 6 GeV{sup 2} region. The hadronic uncertainties associated with an experimentally required cut on m{sub X} potentially spoil the extraction of short distance flavor-changing neutral current couplings. We compute the m{sub X} cut dependence of d{Lambda}(B {yields} X{sub s}{ell}{sup +}{ell}{sup -})/dq{sup 2} using the B {yields} X{sub s}{gamma} shape function, and show that the effect is universal for all short distance contributions in the limit m{sub X}{sup 2} << m{sub B}{sup 2}. This universality is not spoiled by realistic values of the m{sub X} cut, nor by {alpha}{sub s} corrections. Alternatively, normalizing the B {yields} X{sub s}{ell}{sup +}{ell}{sup -} rate to B {yields} X{sub u}{ell}{bar {nu}} with the same cuts removes the main uncertainties. We find that the forward-backward asymmetry vanishes near q{sub 0}{sup 2} = 3 GeV{sup 2}.
Date: December 15, 2005
Creator: Lee, Keith S.M.; Ligeti, Zoltan; Stewart, Iain W. & Tackmann,Frank J.
Partner: UNT Libraries Government Documents Department

Optimization of Superconducting Focusing Quadrupoles for the HighCurrent Experiment

Description: The Heavy Ion Fusion (HIF) program is progressing through a series of physics and technology demonstrations leading to an inertial fusion power plant. The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is exploring the physics of intense beams with high line-charge density. Superconducting focusing quadrupoles have been developed for the HCX magnetic transport studies. A baseline design was selected following several pre-series models. Optimization of the baseline design led to the development of a first prototype that achieved a conductor-limited gradient of 132 T/m in a 70 mm bore, without training, with measured field errors at the 0.1% level. Based on these results, the magnet geometry and fabrication procedures were adjusted to improve the field quality. These modifications were implemented in a second prototype. In this paper, the optimized design is presented and comparisons between the design harmonics and magnetic measurements performed on the new prototype are discussed.
Date: September 16, 2005
Creator: Sabbi, GianLuca; Gourlay, Steve; Gung, Chen-yu; Hafalia, Ray; Lietzke, Alan; Martovetski, Nicolai et al.
Partner: UNT Libraries Government Documents Department