March 1 2019 Report - Feb 18 - March 15
Director - Todd Satogata
Previous two weeks (Feb 18 - March 1) - ADMIN: Group administration: quarterly reports - ADMIN: Sarah Solomon planning meeting (Mar 1) - ADMIN: Postdoc hires, accounting, pursue offer letter - ADMIN: Recommendation letter for high school student (Darren Upton) - ADMIN: Review Phys Rev Letters article - JACOW: Template updates for IPAC'19 - JLEIC: pCDR-100 development, planning; ion complex meetings - OPS: GlueX collaboration meeting (Feb 21) - PERS: Medical leave part days (Feb 26-Mar 1) Next two weeks ( March 4 - March 15) - ADMIN: Group administration: expectations, group meeting/photo (Mar 6) - ADMIN: Postdoc hires, accounting, pursue offer letter(s) - ADMIN: Review NIM article - JACOW: Preparation for IPAC'19 - JLEIC: Booster vacuum tech note development - JLEIC: pCDR-100 development, planning; ion complex meetings - NAPAC19: JACoW assistance with PayPal payment system - OPS: GlueX collaboration meeting (Feb 21) - PERS: Medical leave part day (Mar 4)
Previous two weeks (Feb 18 - March 1) - Optics-on-Call, Machine support - Organize semi-annual progress review of grad. students in Accelerator Science, March 1 - REU/SULI students selection - PRAB paper review Next two weeks (March 4 - March 15) - Machine support - White Paper on 'Publications and Conferences' - Abstract for ERL'19 and invited talk selection (SPC) - Putting together a TN on Fine-tuning gamma_t for FODO lattices
Previous two weeks (Feb 18 - March 1) - Organize impedance meeting for 2/22 - Extensive discussions with Frank Marhauser about broadband impedance calculation method and required accuracy - Discussions with HyeKyoung about crab cavity coupled-bunch instabilities - Foster exchanges between RF and engineering group, and the crab cavity design - Further studies of fundamentals the Landau damping effect in the coupled bunch instability - Participated the Human Performance Improvement (HPI) training by Jlab - Upon request of Steve Benson regarding 3D CSR effects in the e-cooler simulation, I spent some time on follow up the recent development on 3D CSR effects studies in the community Next two weeks (March 4 - March 15) - Continue my discussion with Frank Marhauser on JLEIC broadband impedance - Continue the study of coupled-bunch instability, in particular, to understand the consistency of different theoretical approaches - Continue with my following up of the 3D CSR studies
Previous two weeks (Feb 18 - March 1) - Work on lattices for the new booster stack, tune LEB Next two weeks (March 4 - March 15) - Finish the tuning of the LEB and match the geometry of the HEB
Previous two weeks (Feb 18 - March 1) - Attend ML Workshop (PSI) to give talk - Committee meetings - Conferences & publications committee (wrote a "position paper" stating my strong opposition to tying travel to publication record) - Tactical ML committee - Activities related to ML lunch series (lining up speakers, creating GitHub repository, making announcements, etc.) Next two weeks (March 4 - March 15) - Follow up about building GPU workstation (K20) with Adam and Yves - Follow up with J. Gubeli about LERF LED for isotopes - Follow up with ODU about ML project - Start actually working on ML project again rather than making slides/poster about ML project!
Accelerator R & D - Yuhong Zhang
Previous two weeks (Feb 18 - March 1) - Worked with colleagues on some JLEIC design issues including cooling scheme, ion beam formation scheme, circumference, etc - Attended meetings on bunched beam cooling experiment data analyses - Worked on JLEIC Collaboration Meeting invited speakers and program Next two weeks (March 4 - March 15) - SBIR proposal review
Previous two weeks (Feb 18 - March 1) - Finished the electron collider ring design with PEP-II magnets and presented in the JLEIC R&D meeting. - Worked on the storage ring cooler project - Miscellaneous: attended the JLEIC R&D meeting, attended the IR design teleconference meeting, attended the JLEIC detector meeting, attended the pCDR100 updating meeting Next two weeks (March 4 - March 15) - Optimize the electron collider ring design with PEP-II magnets - Work on the storage ring cooler project
Previous two weeks (Feb 4 - Feb 15) - Nothing to report Next two weeks (Feb 18 - march 1) - Nothing to report
Previous two weeks (Feb 18 - March 1) - IR design: multiple iterations of the IR design with detector designers and engineers, teleconference with SLAC collaborators, detector modeling - Discussions of collider ring circumference - Spin transparency experiment: spin tracking simulations - Prepared an SBIR proposal on space charge mitigation using circular modes - Reviewed a Phase II SBIR proposal - Two energy storage ring cooler: setting up two-energy ring simulation Next two weeks (March 4 - March 15) - Ion collider ring design - Spin tracking for spin transparency test - pCDR-100
Previous two weeks (Feb 18 - March 1) - Preliminary simulations of H- intrabeam stripping in the JLEIC 285 MeV linac. This involved modifying the DTL gradients to convert the linac from H+ to H-. Preliminary simulations with 200000 particles show no losses due to intrabeam strippin - Preliminary simulations of the shortened 150 MeV linac. This version has 3 QWR and 3 HWR modules. With no other optimization, the resultant deuteron and lead exit energies are 90 MeV and 51 MeV, respectively. - First look at a sample of IMP experimental data from the December 2018 run. Primarily looking at longitudinal Schottky data to better understand the analysis codes provided by IMP, and the experimental conditions from the December run. The longitudinal Schottky data exhibit the structure expected from bunched beams, but the observed synchrotron frequency does not correspond to the calculated value and no evidence of sidebands corresponding to transverse Schottky signals are observed. Next two weeks (March 4 - March 15) - Continue work from previous weeks
Computational Physics - Yves Roblin
Previous two weeks (Feb 4 - Feb 15) - Nothing to report Next two weeks (Feb 18 - March 1) - Nothing to report
Previous two weeks (Feb 4 - Feb 15) - Nothing to report Next two weeks (Feb 18 - March 1) - Nothing to report
Previous two weeks (Feb 18 - March 1) - Kernel Independent Cartesian tenor based FMM - Find and fixed a bug in the single level tree generator. Then use the kernel independent Cartesian tensor based FMM to calculate the Coulomb kernel, modified Coulomb kernel, and stokes kernel with various number of particles and various orders. Made plots to demonstrate the efficiency of the algorithm scales linearly with the number of particles for Cartensions tensor with rank 2, 4, and 6, the relative errors reducing as the rank increasing, and the computation time compared with direct calculation for particle numbers up to 5,000,000. These numerical results are used in the poster about the kernel Independent Cartesian tensor FMM. - CSE 2019 Conference - Attended the first two and a half day of the 2019 Computational Science and Engineering Conference. This is a large conference. There is only one plenary talk and more than 20 parallel sessions in the morning or afternoon. Most topics can be classified by three categories: software development and engineering, machine learning, and numerical methods for PDE, ODE, and linear system. I attended the sessions on the following three topics: improve the quality of scientific software, implement of machine learning in research, and integral equation. In the machine learning sessions, it is discussed how to use the physical laws to improve the learning process or how to enforce the conservation law, symmetry, or boundary condition in the learning algorithm. In the integral equation session, the talks focus on the quadrature by extension (QBX) method, including the development and the implementation of QBX. Our work on the kernel independent Cartesian tensor FMM was presented in the poster session on Tuesday evening. I had discussions on FMM and high order derivative calculations using differential algebra with other attendees. Next two weeks (March 4 - March 15) - Cooling simulation for preCDR - Add the feature of luminosity calculation to JSPEC - Finish space charge effect in friction force simulation in JSPEC - Discuss with Slava about dispersive cooling simulation
Diagnostic Development - Kevin Jordan
Previous two weeks (Feb 18 - March 1) - Continued helping to troubleshoot the LCLS-II LLRF with Curt, Larry, Rama & remote folks from SLAC, & Berkeley. Those folks are to arrive March 4 & spend the week working through scripting errors & bad communications. - Pushed for HCO of the isotope injector beam line to 0G dump location. Terminated the 0G dump w/1kΩ and had cable routed to control room scope for current measurement. With luck we will have beam in the injector by March 8. - Prepared a BNNT Bucky paper for the Radiabeam SBIR I halo monitor. This will be installed March 4 in the LERF linac on a ‘harp’ trip actuator. See attached photo. Next two weeks (March 4 - March 15) - I have been preparing for the IBIC PC meeting in Malmo next week, and on 3/4/19 joined Haipeng for a RF vendor visit for the magnetron project.
Previous two weeks (Feb 18 - March 1) - Traveled to Radiabeam for a design review of the high power wire scanner. The trip was very productive. We were able to see the scanner in operation, was trained in how to replace the wire card, ironed out the I/O and revised the schedule. - Worked on the design and simulations for the upcoming review of the isotope production radiation shielding. - Completed the assembly and testing of the x-ray viewer for the bubble experiment. User was very happy with the operation and image quality. - Met with Mike T and Brian F. about the ARC 7 SLM design. After some discussion we decided to make some small changes in the optics layout and specifically with the location of the filter wheels. - Met with Mike T. and Jianxum Y. about the functionality of the high power wire scanner. Next two weeks (March 4 - March 15) - Will work with S&A on the positioning of the MDQ dipole in the LERF. The chamber is off by 6mm requiring a shift in the DQ. - Will work with VAC to show them how to replace the viewer flags in the LERF to YAG screens. We have five to replace. - Will work with I&C on the LERF viewers and the LDRDS. - Will have a design review of the isotope production radiation shielding. - Will travel to Argonne to visit their isotope production facility.
Previous two weeks (Feb 18 - March 1) - preparing for the CLAS12 Collaboration accelerator status presentation - Responding to the very new-to-me information that the spin precession in the accelerator now, in the asymmetric acceleration mode in use to relieve stress on the North Linac, corresponds to 0.33% higher energy rather than 0.27%. This requires resolution before action. - Harps and magnet diagnostics still pending - New items: discussions on in-situ cavity cleaning and on window arc test proposal (ATLis 18905 Attempted window charge relaxation in a single SRF cavity ) - Absolute orbit analysis of West Arc trajectories to localize rolled dipoles - verified roll undone, but have not progressed to localizing rolled dipoles. Next two weeks (March 4 - March 15) - All of these will be pursued in the coming two weeks, plus the nonlinearity checks from rayTrace mentioned last week. [Additional comment: The proposed window arc test is a follow-up on a long-ago single-shot phase switch test using the gang phase in one or both linacs. At that time I made a simple comparison of linac arc rate in the short time after the phase switch against the average arc rate. No change was clear in the comparison. The strongest result might have been the linac being free of arcs for the next hour or a few. No careful analysis was done of the very cursory test. But the follow-on that occurred to me was to accompany each system FSD trip with a deliberate 180 degree transient phase flip of a frequently arc-fault tripping cavity to determine whether spontaneous arc faults were suppressed. If so, then it may be that the cavity window discharge may have been preemptively triggered somewhere along its charge-up time sequence. Targeted followup of such an observation might provide a hint about mechanism. Any such information would be of great interest and might be of great utility.
LERF - Steve Benson
Previous two weeks (Feb 18 - March 1) - Wrote up new draft for Pre-CDR-100 chapter 6 Worked with CIS and Ops to complete hot checkout for the LERF injector. - Re-reviewed PRST paper and reviewed SBIR phase II proposal Met with Radcon staff to determine shipping strategy for non-irradiated gallium isotope target. - Held Cooler ring meeting to go over the new Chapter 6 for the Pre-CDR-100. - Set up the first seminar of the year for Subashina DaSilva Met with Ron Sakach to discuss patent Number 62/001,656 Next two weeks (March 4 - March 15) - Submit new text for LOD and safety envelope for LERF. - Summarize the ERLs for EIC workshop. - Turn on beam in the LERF injector - Derive new Beam authorization destinations in the LERF Host seminar on March 7. - Visit Argonne National lab to go over Actinium production details.
Previous two weeks (Feb 4 - Feb 15) - I returned from Europe on February 2. I had completed my report for the HCERES Review at Orsay while on vacation. I spent a couple of days finishing my report for the AMICI Meeting, then wrote a trip report to management for both meetings, including the reports. - I learned that a full-size booster was being adopted for the ion injection chain and realized that this configuration would permit the creation of a bunch pattern that would cancel the gap transients in the RF systems of the Ion Colliding Ring. I then spent a fair amount of time looking at different options. - I came up with a design for a supplemental container for the isotope target crucible. I don’t think this will actually be needed for the isotope program (maybe later when we have higher radiation levels in the crucible). However, the design could be used much more widely so I have submitted an invention disclosure. - Joe Gubeli and Keith Welch have made great progress with the shielding design for the isotope irradiations and asked for comments. I suggested using a borescope to make sure that the dump closes properly, including the correct positioning of the target wrt the radiator. I also spent time looking at TIMs (Thermal Interface Materials) to improve cooling of the crucible, following a productive discussion with Dave Meekins. The final choice will probably be pure Tin, almost as soft and thermally conductive as Indium, but with a higher melting temperature. - I discussed with Geoff Krafft the possibility of having a summer student to carry out thermal transfer measurements as part of our design effort to develop a crucible capable of dissipating 50 kW. Next two weeks (Feb 18 - March 1) - In the next two weeks, I will be finalizing the options for gap transient suppression with Bob Rimmer and Jiquan Guo, itemizing the additional hardware required. The Isotope work looks like it will be on hiatus as the LCLS II commissioning is starting. I am planning a mini-review of the target shielding, but that must await until after Joe Gubeli gets back from California (he is following up on an SBIR contract). - I feel I should be doing something on electron bam cooling, but not sure how to be useful. I have made several recommendations over the last year (APEX gun, lower RF frequency injector, higher harmonic cavities) but these are only now beginning to be examined. I would like to see some results before proposing anything else.