stephenbrooks.orgWork-Related ThingsTechnical Reports and Papers
Up

Technical Reports and Papers

I am currently (2013) working with the Collider-Accelerator Department at Brookhaven National Laboratory.  As well as wherever else they may be published, I am putting a copy of all my reports for work up here on the web.

TypeTitleDateNotes
Seminar2024-3[pptx]Ultra Low Emittance Beams in Ion Traps and Lab Visits in Japan (.pptx, 201 MB)February 2024Seminar given at BNL Collider-Accelerator Department
Conference Paper2023-12[pdf]Ultra-low Emittance Bunches from Laser Cooled Ion Traps for Intense Focal Points (.pdf, 1.21 MB)October 2023Paper presented at HB2023
Conference Talk2023-5[pptx]Ultra-low Emittance Bunches from Laser Cooled Ion Traps for Intense Focal Points (.pptx, 165 MB)October 2023Invited talk given at HB2023
Seminar2023-11[pptx]Fixed-Field Accelerators with Fixed Tunes... AND good Magnetic Efficiency (.pptx, 6.59 MB)September 2023Seminar given at RAL ISIS accelerator group.  Combination of topics from FFA'22 and '23 with four slides from Dejan Trbojevic
Talk2023-10[pptx]Permanent Magnet and Electromagnet Designs for Nonlinear FFA Fields (.pptx, 5.69 MB)September 2023Talk given at FFA 2023
Proposal2023-8[pdf]Ion trap test stand and laser cooling studies of ultra-low emittance bunches for high luminosity (.pdf, 1.70 MB)July 2023Lab-directed R&D $400k over 2 years
Research Note2023-7[pdf]Higher-Order Corrections to Optimisers based on Newton's Method (.pdf, 679 KB)July 2023Speeds up Levenberg–Marquardt algorithm too
Research Note2023-6[pdf] Integrals of Polynomial Functions over Spheres and Balls (.pdf, 208 KB)June 2023Standard stuff but I wanted to write it up; useful for integrals over ellipsoidal beams etc.
Conference Poster2023-4[pdf]Non-Scaling Fixed-Field Proton Accelerator with Constant Tunes (.pdf, 2.04 MB) / View as imageMay 2023Poster Presented at IPAC'23
Conference Poster2023-3[pdf]Open-Midplane Gradient Permanent Magnet with 1.53T Peak Field (.pdf, 2.18 MB) / View as imageMay 2023Poster Presented at IPAC'23
Conference Paper2023-2[pdf]Non-Scaling Fixed-Field Proton Accelerator with Constant Tunes (.pdf, 736 KB)May 2023Paper presented at IPAC'23
Conference Paper2023-1[pdf]Open-Midplane Gradient Permanent Magnet with 1.53T Peak Field (.pdf, 1.70 MB)May 2023Paper presented at IPAC'23
Proposal2023-9[pdf]Ultra-low Emittance Beams from Ion Traps for High Precision Collisions (.pdf, 1.90 MB)March 2023This was not funded but this year's LDRD on the same topic was
Conference Talk2022-5[pptx]CBETA Multi-Turn Studies and Various Beam Dynamics Issues (.pptx, 18.6 MB)October 2022Invited talk given at ERL 2022 (the FFA 2020 talk again with a few slides from Kirsten Deitrick)
Talk2022-4[pptx]Fixed-Tune Non-Scaling FFAs (.pptx, 3.48 MB)September 2022Talk given at FFA 2022
Conference Poster2022-2[pdf]Poster Presented at IPAC'22 (.pdf, 1.71 MB)June 2022
Conference Paper2022-1[pdf]Permanent Magnets for the CEBAF 24GeV Upgrade (.pdf, 770 KB)June 2022Paper presented at IPAC'22
Research Note2022-3[pdf]Paraxial, Thin-Lens Analysis of Fixed-Tune, Non-Scaling FFAs with Two Magnets per Cell (.pdf, 199 KB)May 2022Updated 2022-May-06 to reference straight scaling FFA case
Research Note2021-6[pdf]Integrated Fields of Permanent Magnet Dipole Trims (.pdf, 114 KB)October 2021An easy empirical method for calculating the integrated field of permanent magnet dipole trims
Talk ▶2021-5[pptx]CEBAF 20GeV FFA Upgrade (.pptx, 7.35 MB)September 2021Talk given at FFA 2021
Conference Talk ▶2021-4[pptx]Modified Halbach Magnets for Emerging Accelerator Applications (.pptx, 10.6 MB)May 2021Talk given at IPAC'21
Conference Paper2021-2[pdf]Modified Halbach Magnets for Emerging Accelerator Applications (.pdf, 644 KB)May 2021Paper presented at IPAC'21
Proposal2021-7[pdf]High-Gradient Permanent Magnets for Emerging Accelerator Applications (.pdf, 1.04 MB)April 2021Lab-directed R&D $400k over 2 years
Talk ▶2021-3[pptx]Enhanced Field Quality Halbach Magnets for Particle Accelerators (.pptx, 26.7 MB)April 2021Talk given at IET workshop on Simulations in Particle Accelerators
Seminar2021-1[pptx]Permanent Magnets for Emerging Accelerator Applications (.pptx, 23.1 MB)January 2021Joint DESY and University of Hamburg Accelerator Physics Seminar
Research Note2020-9[pdf]The Connection of Adiabaticity to the Fourier Transform (.pdf, 136 KB)December 2020Derivation of adiabatic transitions acting on a simple harmonic oscillator (standard stuff)
Talk ▶2020-7[pptx]Various Studies at the CBETA 4-Turn FFA ERL (.pptx, 17.8 MB)December 2020Talk given at FFA 2020
Journal Paper2020-8[pdf]Permanent magnets for the return loop of the Cornell-Brookhaven energy recovery linac test accelerator (.pdf, 2.56 MB)November 2020
Research Note2020-6[pdf]Integrals of Distorted Gaussian Functions (.pdf, 138 KB)May 2020Formulas a by-product of note 2020-5 but never used, may be related to 2017-5 also
Research Note2020-5[pdf]Smoothed Retarded Potentials and Fields (.pdf, 252 KB)May 2020Liénard–Wiechert potential with a smoothing term
Research Note2020-4[pdf]FETS-VFFA Cell using Contour-Based Magnets (.pdf, 378 KB)February 2020Very minor error (Z' is convolved with atan, not Z) corrected 2020-Feb-28
Research Note2020-3[pdf]Magnetic Potential of a Finite Wire (.pdf, 187 KB)January 2020Compare note 2011-7, scalar potential has a closed form but messy, useful for current-dominated 3D magnet design
Talk2019-10[pptx]CBETA: a 4-pass superconducting ERL with permanent FFA magnet return arc (.pptx, 25.7 MB)November 2019Given at FFA'19 Meeting, PSI; updated version of EIC talk
Talk2019-9[pptx]Permanent Magnet VFFA for 18GeV Electron Acceleration (.pptx, 20.3 MB)November 2019Talk given at FFA 2019
Talk2019-8[pptx]CBETA: a 4-pass superconducting ERL with combined permanent magnet return arc (.pptx, 24.4 MB)October 2019Given at EIC Meeting, ANL; slightly updated copy of Boston talk
Talk2019-6[pptx]CBETA: a 4-pass superconducting ERL with combined permanent magnet return arc (.pptx, 14.8 MB)August 2019Talk given at DPF2019, Boston
Research Note2019-7[pdf]Magnetic Field of a Winding Sheet defined by a Contour Function (.pdf, 174 KB)July 2019Possible method for designing windings for superconducting VFFA magnets (updated September 2019)
Conference Poster2019-4[pdf]Poster Presented at IPAC'19 (.pdf, 2.53 MB)May 2019
Conference Paper2019-1[pdf]CBETA Permanent Magnet Production Run (.pdf, 2.34 MB)May 2019Paper presented at IPAC'19, co-authors: G. Mahler, J. Tuozzolo, R. Michnoff
Research Note2019-3[pdf]Integrated Field of a Finite Wire (.pdf, 141 KB)January 2019Standard stuff, useful formula for current-dominated 3D magnet design
Seminar2019-2[pptx]Permanent Magnet Accelerator Arcs with Linear Fields (.pptx, 48.9 MB)January 2019Seminar at the John Adams Institute, Oxford
Talk2018-4[pptx]CBETA Magnet Production (.pptx, 9.98 MB)September 2018Talk given at FFA 2018
Conference Paper2018-2[pdf]Potential and Issues for Future Accelerators and Ultimate Colliders (.pdf, 1.33 MB)May 2018Paper presented at IPAC'18
Conference Talk2018-1[pptx]Potential and Issues for Future Accelerators and Ultimate Colliders (.pptx, 7.26 MB)May 2018Invited talk given at IPAC'18
Research Note2017-6[pdf]Magnetic Field from an Infinite Array of Wires (.pdf, 148 KB)September 2017Useful for parallel iron mirror planes
Talk2017-3[pptx]Test of Linear-Field Non-Scaling FFAG Arc with a Wide Energy Range (.pptx, 28.7 MB)September 2017Talk given at FFAG 2017
Research Note2017-5[pdf](Draft) Wave Equations with the Exponential of a Quadratic as a Solution (.pdf, 307 KB)August 2017
Research Note2017-4[pdf](Draft) Optical Function Evolution in Generalised FFAG Transfer Lines (.pdf, 168 KB)July 2017Mainly standard optics formulae, plus definition of problem to be optimised
Conference Poster2017-2[pdf]Poster Presented at IPAC'17 (.pdf, 1.22 MB)May 2017
Conference Paper2017-1[pdf]Production of Low Cost, High Field Quality Halbach Magnets (.pdf, 716 KB)May 2017Paper presented at IPAC'17
Talk2016-4[pptx]View on Future Accelerators/Concepts (.pptx, 3.89 MB)December 2016Talk given at F3iA 2016, about future directions of accelerators beyond 2050
Research Note2016-3[pdf]Analytic Formulae for Fields in Windowframe Magnets (.pdf, 136 KB)November 2016Well-known but I wanted to write it down for later
Proposal2016-2[pdf]Test of a Large Energy Acceptance NS-FFAG Arc at the ATF (.pdf, 1.72 MB)September 2016
Talk2016-1[pptx]Generalised Halbach Magnets for a Non-Scaling FFAG Arc (.pptx, 3.30 MB)September 2016Talk given at FFAG 2016
Machine Note2015-5[pdf]Decision on the number of turns in the eRHIC Nov'15 design (.pdf, 304 KB)December 2015Results of eRHIC design discussions
Talk2015-4[pptx]FFAG Designs for eRHIC and Cβ Return Loops (.pptx, 27.5 MB)November 2015Talk given at November 2015 eRHIC R&D Review
Conference Talk2015-2[pdf]eRHIC: an Efficient Multi-Pass ERL based on FFAG Return Arcs (.pdf, 2.97 MB)June 2015Invited talk given at ERL 2015
Conference Paper2015-1[pdf]ERL with Non-Scaling Fixed Field Alternating Gradient Lattice for eRHIC (.pdf, 755 KB)May 2015Dejan Trbojevic's paper at IPAC'15, coauthored and presented by me
Research Note2015-3[pdf]Bounded Approximate Solutions of Linear Systems using SVD (.pdf, 183 KB)April 2015Probably well-known but I wanted to go through the derivation; updated 2023-Mar-06 with identity with the Levenberg–Marquardt algorithm; updated 2023-Dec-18 with maximising a scalar quadratic
Proposal2014-9[pdf]Electron Model of a Three-Dimensional Relativistic Cyclotron (.pdf, 4.35 MB)November 2014
Talk2014-8[pdf]Cornell ERL-FFAG Lattice (.pdf, 2.07 MB)September 2014Talk given at FFAG'14
Talk2014-7[pdf]eRHIC FFAG Lattice Design (.pdf, 4.30 MB)September 2014Combination of EIC'14 slides with updates on 30T/m eRHIC cell
Conference Poster2014-6[pdf]FFAG Straight Sections and Bypasses in eRHIC (.pdf, 802 KB)September 2014Poster Presented at FFAG'14
Conference Talk2014-4[ppt]Vertical Orbit-Excursion FFAGs (VFFAGs) and 3D Cyclotrons (.ppt, 12.6 MB)June 2014Invited talk given at IPAC'14
Conference Paper2014-3[pdf]Vertical Orbit-excursion Fixed Field Alternating Gradient Accelerators (V-FFAGs) and 3D Cyclotrons (.pdf, 1.25 MB)June 2014Paper presented at IPAC'14
Research Note2014-2[pdf]Extrapolation of Magnetic Fields from a Curved Surface (.pdf, 273 KB)May 2014UPDATE: 2014-Apr-28 fixed really subtle sign error; UPDATE: 2014-May-13 expanded to give more examples
Talk2014-1[ppt]FFAG Lattice Design of eRHIC and LHeC (.ppt, 4.92 MB)March 2014Part of joint talk given at EIC'14
Journal Paper2013-6[pdf]Vertical Orbit Excursion Fixed Field Alternating Gradient Accelerators (.pdf, 3.15 MB)August 2013
Research Note2013-10[pdf]Off-Axis Magnetic Fields Extrapolated from On-Axis Multipoles (.pdf, 167 KB)July 2013Includes computer implementation details for fast evaluation using precalculated fieldmaps
Research Note2013-9[pdf]Beam Distribution with e-x-like Tails (.pdf, 178 KB)July 2013Includes particle weighting method for simulation of tail losses
Conference Poster2013-8[pdf]Poster Presented at IPAC'13 (.pdf, 3.65 MB) / View as imageMay 2013
Conference Paper2013-1[pdf]Configurable Field Magnets for a Proton Beam Dynamics R&D Ring (.pdf, 1.07 MB)May 2013Paper presented at IPAC'13
Seminar2013-7[pdf] Vertical Orbit-Excursion FFAGs (VFFAGs) (.pdf, 7.91 MB)April 2013Talk given at PASI'13 and as a seminar at Brookhaven National Laboratory
Research Note2013-2[pdf]Exact Tracking in s in a Magnetic Field (.pdf, 53 KB)April 2013Exact (not paraxially approximated) particle dynamics including horizontal beamline curvature.  IMPORTANT UPDATE: expressions for dx/ds, dy/ds added; old ones not correct
Talk2013-5[pdf]Status of MARS Simulations of ISIS Targets (.pdf, 1.80 MB)February 2013
Talk2013-4[pdf]Blue Skies Magnets (.pdf, 1.03 MB)February 2013Magnets required by VFFAGs and the proton omni-ring
Research Note2013-3[pdf](Draft) Isochronous, Scaling VFFAGs Dominated by Strong Focussing (.pdf, 151 KB)January 2013Lower bound on energies in isochronous VFFAGs under certain simplifying assumptions
Conference Poster2012-7[pdf]Poster Presented at HB2012 (.pdf, 2.56 MB) / View as imageSeptember 2012
Research Note2012-6[pdf]Arbitrary Beams in Uniform Pipes (.pdf, 263 KB)September 2012Exact Coulomb potentials for beam slices; derivation of space charge g factor using normal modes; longitudinal space charge formulae
Conference Paper2012-5[pdf]Acceleration in Vertical Orbit Excursion FFAGs with Edge Focussing (.pdf, 817 KB)September 2012Paper presented at HB2012
Research Note2012-8[pdf]Fields of Moving, Non-Accelerating Charges in the Present Time (.pdf, 131 KB)August 2012Constant velocity approximation for 4D space charge
Conference Poster2012-4[pdf]Poster Presented at IPAC'12 (.pdf, 2.04 MB) / View as imageMay 2012
Talk2012-3[ppt]ISIS Target Design Process Flowcharts (.ppt, 879 KB)May 2012From PASI targets meeting; flowcharts in collaboration with David Jenkins
Conference Paper2012-1[pdf]Vertical Orbit Excursion FFAG Accelerators with Edge Focussing (.pdf, 577 KB)May 2012Paper presented at IPAC'12
Research Note2012-2[pdf]Exact Tracking in z in a Magnetic Field (.pdf, 136 KB)April 2012Exact version of a formula that is commonly approximated paraxially
Research Note2011-6[pdf]Fringe Fields for VFFAG Magnets with Edge Angles (.pdf, 168 KB)November 2011Corrected 2011-Nov-08
Research Note2011-7[pdf]Magnet Field of a Finite Wire (.pdf, 119 KB)October 2011Standard stuff, useful formula for current-dominated 3D magnet design
Talk2011-5[pdf]Talk Given at FFAG'11: Vertical Orbit Excursion FFAGs and Other Things (.pdf, 2.55 MB)September 2011Compilation of previous work
Conference Poster2011-4[pdf]Poster Presented at IPAC'11 (.pdf, 1.39 MB) / View as imageSeptember 2011
Conference Paper2011-1[pdf]Three-Lens Lattices for Extending the Energy Range of Non-scaling FFAGs (.pdf, 690 KB)September 2011Paper presented at IPAC'11
Research Note2011-3[pdf]Calculating Coupled Tunes from a 4D Transfer Matrix (.pdf, 147 KB)August 2011
Outreach2011-2[doc]Article on VFFAGs for ASTeC Annual Report 2010/11 (.doc, 860 KB)June 2011
Talk2010-7[pdf]Talk on Tapered Pion Targets for the Neutrino Factory (.pdf, 452 KB)November 2010Talk version of IPAC'10 paper and poster, given for UKNF meeting
Proposal2010-8[zip]Test of a Vertical Orbit Excursion FFAG (VFFAG) using the EMMA Test Area (.zip, 885 KB)October 2010Version 1.1 of the proposal
Thesis2010-6[pdf]Muon Capture Schemes for the Neutrino Factory (.pdf, 8.63 MB)September 2010DPhil thesis submitted to Oxford particle physics sub-department
Conference Poster2010-4[pdf]Poster Presented at HB2010 (.pdf, 1.43 MB) / View as imageSeptember 2010
Conference Paper2010-3[pdf]Vertical Orbit Excursion FFAGs (.pdf, 1.06 MB)September 2010Paper presented at HB2010
Research Note2010-5[pdf](Draft) Fixing the Tune of Nonscaling FFAGs in the Thin Lens Paraxial Approximation (.pdf, 191 KB)August 2010Maths dump showing the methodology I have developed for tune fixing
Conference Poster2010-2[pdf]Poster Presented at IPAC'10 (.pdf, 774 KB) / View as imageMay 2010
Conference Paper2010-1[pdf]Optimising Pion Production Target Shapes for the Neutrino Factory (.pdf, 257 KB)May 2010Paper presented at IPAC'10
Talk2009-7[pdf]Talk on Alternative Upgrade Options involving VOX-FFAGs at the ISIS MW Upgrades Meeting (.pdf, 273 KB)May 2009
Conference Poster2009-6[pdf]Poster Presented at PAC'09 (.pdf, 635 KB) / View as imageMay 2009
Conference Paper2009-2[pdf]Extending the Energy Range of 50Hz Proton FFAGs (.pdf, 153 KB)May 2009Paper presented at PAC'09
Outreach2009-5[ppt]Poster presented at the John Adams Institute Review on the Neutrino Factory (.ppt, 1.02 MB)February 2009
Talk2009-4[pdf]Talk on the Neutrino Factory given at RAL/DL Joint Accelerator Workshop (.pdf, 1.44 MB)January 2009
Talk2008-4[zip]Pion production data presented at the 2nd Oxford–Princeton High-Power Target Workshop (.zip, 396 KB)November 2008Presented as three Excel files
Conference Paper2008-3[pdf]Simulations of pion production from water-cooled solid targets using MARS15 (.pdf, 277 KB)September 2008NuFact'08 Conference Paper
Talk2008-2[ppt]Talk Given at UKNF Meeting on Combining HARP Experimental Data with Muon Transmission Estimates for the ISS Baseline (.ppt, 388 KB)September 2008
Research Note2008-5[pdf]Notes on 2+1D Space Charge (.pdf, 47 KB)April 2008Relation between 3D and 2+1D space charge force models, by approximating with a sum of separable charge distributions
Conference Talk2008-1[ppt]Talk Given at UKNF Meeting on Water-Cooled Targets (.ppt, 579 KB)April 2008Also presented at NuFact'08
Research Note2007-3[html]Comparison of HARP tantalum 5% interaction length data against simulations using MARS 15.07August 2007
Outreach2007-2[ppt]UKNF Conceptual Design Poster presented at the ASTeC Advisory Board Poster Session (.ppt, 6.03 MB)February 2007"Links" were to other posters presented in the same session
Talk2006-9[ppt]Talk Given at Frascati BENE meeting: Lower-Frequency RF Phase Rotation (.ppt, 318 KB)November 2006Includes Matthew McCullough's summer work
Outreach2006-8[doc]Chapter written for Distributed Computing Projects book (.doc, 1.02 MB)November 2006(Draft)
Conference Talk2006-6[ppt]Talk Given at NuFact'06: Lower-Frequency RF Phase Rotation Techniques for Both Muon Signs (.ppt, 467 KB)August 2006You can also download the files for animation (under Windows) from the 'player' subdirectory
Conference Poster2006-5[ppt]Poster Presented at EPAC'06 (.ppt, 574 KB) / View as imageJune 2006
Conference Paper2006-1[pdf]Secondary Particle Production and Capture for Muon Accelerator Applications (.pdf, 383 KB)June 2006Paper presented at EPAC'06
Talk2006-4[ppt]Target Yield Considerations Talk Given at RAL Scoping Study Meeting (.ppt, 4.24 MB)April 2006
Talk2006-2[ppt]Talk Given at the John Adams Institute Advisory Board Meeting (.ppt, 766 KB)February 2006A short summary talk, only 10-15 minutes long
Research Note2006-3[pdf]Monte Carlo Modelling of Many-Body Decays (.pdf, 145 KB)January 2006Note describing the multi-particle decay algorithm in Muon1 version 4.43 and above
Outreach2005-9[ppt]Poster Presented at the 'SET for Britain' event at the House of Commons (.ppt, 4.70 MB) / View as imageNovember 2005Much expanded and updated form of the CERN50 poster section I did in September 2004
Talk2005-8[ppt]Talk Given at CERN International Scoping Study meeting, Comparing Pion Production in MARS15 and GEANT4 (.ppt, 680 KB)September 2005Similar talk again, some initial slides on pulse structure added for context
Conference Paper2005-5[pdf]Computed Pion Yields from a Tantalum Rod Target: Comparing MARS15 and GEANT4 Across Proton Energies (.pdf, 305 KB)September 2005NuFact'05 Conference Paper
Talk2005-7[ppt]Talk Given at European Neutrino Group (ENG) meeting, Comparing Pion Production in MARS15 and GEANT4 (.ppt, 722 KB)August 2005This is almost exactly the same as the NuFact'05 talk I gave; GEANT4 results thanks to Kenny Walaron
Conference Talk2005-4[ppt]Talk Presented at NuFact'05, Comparing Pion Production in MARS15 and GEANT4 (.ppt, 693 KB)June 2005GEANT4 results thanks to Kenny Walaron
Talk2005-3[ppt]Talk on Target Pion Production Studies at Muon Week, CERN (.ppt, 436 KB)March 2005
Research Note2005-2[html]Simulations of Pion Production in a Tantalum Rod Target using MARS15January 2005
Talk2004-7[ppt]Research Status Talk at Muon Week in DESY (.ppt, 397 KB) / Web versionNovember 2004
Outreach2004-6[ppt]Poster for the CERN50 UK technology transfer event (.ppt, 1.48 MB) / View as imageSeptember 2004Collaborative poster: top section by Ken Long; middle section by myself; front-end test stand by David Findlay; target studies by Roger Bennett.
Conference Poster2004-5[ppt]Poster Presented at EPAC'04 (.ppt, 2.10 MB) / View as imageJuly 2004
Outreach2004-4[html]Article in PPARC's Frontiers magazine, about the Muon1 projectJune 2004Original site is down so this is an HTML snapshot
Conference Paper2004-2[html]Quantitative Optimisation Studies of the Muon Front-End for a Neutrino FactoryJune 2004Paper presented at EPAC'04
Talk2004-3[ppt]Research Status Talk at UK Neutrino Factory Meeting (.ppt, 2.08 MB) / Web versionMay 2004
Talk2004-1[ppt]General Research Talk at RAL/DL Joint Accelerator Workshop (.ppt, 1.41 MB) / Web versionApril 2004
Research Note2003-1[html]Simulations of Neutrino Factory Muon Capture with Chicane (58 KB)December 2003
Talk2003-2[ppt]Research Status Talk at ISIS Accelerator Division Meeting (.ppt, 1.18 MB) / Web versionNovember 2003
Research Note2002-1[html]Simulations of Neutrino Factory Muon Capture with ChicaneJune 2002

Peer-reviewed papers in which I appear as part of a collaboration are below:

See also my ORCID iD.

: contact : - - -
E-mail: sbstrudel characterstephenbrooks.orgTwitter: stephenjbrooksMastodon: strudel charactersjbstrudel charactermstdn.io RSS feed25.10millionaccesses