2018-03-16

Director - M. Spata
No report.

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Accelerator Physics - T. Satogata
Todd Satogata

  Previous two weeks (Mar 5-Mar 16)
     - SICK: Fri Mar 9
     - ADMIN: Leadership/group meetings, Lab Plan update, Drupal training, appraisal
     - JLEIC: Coordinate lattice freeze, organization of next steps
     - JLEIC: Work with Yuhong to develop collaboration meet program
     - IPAC18: Scientific secretariat work (program codes, booklets, student program)
     - ODU: Continue teaching PHYS 417/517 Tue/Thu, Randy advising
     - OPS: Plan OOC, Beam Studies (Tuesdays), BTeam, optics support/tuning meetings
     - OPS: Hall D active collimator calibration planning, 12 GeV parameter meeting
  Next two weeks (Mar 19-Mar 30)
     - ADMIN: Leadership/group meetings, cancer therapy brainstorming meet
     - ADMIN: Dave Douglas retirement lunch org (Mar 30)
     - JLEIC: Prepare collaboration meeting talks, templates for speakers
     - JLEIC: Collaboration Meeting (Mar 26-28), Impedance meeting (Mar 19)
     - IPAC18: Scientific secretariat work (poster codes, booklets, student program)
     - ODU: Continue teaching PHYS 417/517 Tue/Thu, Randy advising
     - ODU: Potential graduate student visit (Fri Mar 23)
     - OPS: Plan OOC, Beam Studies (Tuesdays), BTeam, optics support/tuning meetings
     - OPS: 12 GeV parameter document convergence input

Alex Bogacz

   Previous two weeks (Mar 5-Mar 16)
     - 12 GeV Beam Parameter Table
     - REU candidates selection
     - M56 control revisited
   Next two weeks (Mar 19-Mar 30)
     - IPAC'18 Peer Rev.
     - 12 GeV Beam Requirements
     - Tech Transfer Workshop
     - JLEIC: Collaboration Meeting (March 26-28)

David Douglas

   Previous two weeks (Mar 5-Mar 16)
     - Finished up "Why PERLE" note requested by Max Klein
     - Generated better-optimized "Faux FFAG" arc with ideal solution iterating
       between spreadsheet and DIMAD
     - Revised CCR matching, to Chris for CCR multiturn model
   Next two weeks (Mar 19-Mar 30)
     - Iterate Faux FFG arc with thin quad fringe fields
     - Updating ERL/CCR matching, adjust working point of CCR
     - Work with Chris to followup on Cheng-Ying's uBI gain suggestions
     - JLEIC: Collaboration Meeting (Mar 26-28)
     - Retirement process!

Rui Li

   Previous two weeks (Mar 5-Mar 16)
     - JLEIC: Evaluate ion trapping in e-ring, clearing gap evaluation, with
       concerns appearing for fast-ion instability at 3 and 5 GeV
     - JLEIC: Contact Demin Zhou re IR bellow design, coordinate with Wiseman
   Next two weeks (Mar 19-Mar 30)
     - JLEIC: Summarize estimates for collective effects, prepare talk for
       collaboration meeting
     - JLEIC: Collaboration Meeting (Mar 26-28), Impedance meeting (Mar 19)
     - Start writing papers for IPAC18

Ed Nissen

   Previous two weeks (Mar 5-Mar 16)
     - VACATION: Mon Mar 5, SICK: 1/2 Tue Mar 6, Wed Mar 7
     - JLEIC: DESIREE gear changing tests LDRD LOI preparation
     - JLEIC: Finish booster cleanup, working point, ramping development
     - JLEIC: Retune booster to reduce overall sextupole strengths
   Next two weeks (Mar 19-Mar 30)
     - JLEIC: Continue DESIREE LDRD preparation, budgeting
     - JLEIC: Prepare talk for collaboration meeting
     - JLEIC: Collaboration Meeting (Mar 26-28)

Chris Tennant

   Previous two weeks (Mar 5-Mar 16)
     - JLEIC: revisiting some mBI analysis for one of the CCR arcs
       (found a numerical artifact that for certain values of the
       mesh_number, where the gain is orders of magnitude larger)
     - JLEIC: increasing fidelity of CCR S2E lattice - namely, adding the
       kickers in the beam exchange region and trying to wrap my head
       around how it works
     - JLEIC: able to get good agreement - with CSR - between elegant and GPT
       for the "simple arc" lattice
     - IPAC18: foreign travel training!
   Next two weeks (Mar 19-Mar 30)
     - JLEIC: Prepare talk for collaboration meeting
     - JLEIC: Collaboration Meeting (Mar 26-28)
     - IPAC18: prep (paper and poster)

Randy Gamage

   Previous two weeks (Mar 5-Mar 16)
     - Dissertation writing: Working on bunch splitting chapter
   Next two weeks (Mar 19-Mar 30)
     - Dissertation writing: Revise bunch compressor chapter
     - Dissertation writing: Continue bunch splitting chapter
     - JLEIC: Meet with Rui Li, get ideas on esme instability tests

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Accelerator R and D - Y. Zhang
Slava Derebenev

• Continued development of advanced concepts for JLEIC high energy cooler

Fanglei Lin

• Finished the electron collider ring design and presented in the JLEIC R&D meeting.
• Performed tune scan and continued misalignment study for the electron ring.
• Continued setting up spin tracking in the BMAD using the latest electron ring design.
• Miscellaneous: attended discussion of IP magnets with engineers, attended the JLEIC R&D meetings, attended JLEIC detector meeting, attended JLEIC general meetings.

Vasiliy Morozov

• Ion collider ring design: development of a new design version geometrically matched to the electron collider ring and including various updates.
• Interaction region design: meetings with engineers and detector designers.
• Geometry tagging LDRD: teleconferences with collaborators.

Amy Sy

• Compiling recent toroidal merger simulation results and methods for presentation at IPAC 2018.
• Set up WARP simulation environment to model two counter-propagating magnetized beams in an accelerating field. Magnetized beam is generated using a flat beam transform, and the two beams currently interact only once in the "linac". Currently setting up diagnostics to evaluate emittance growth.
• Survey of transverse feedback systems: for hadron machines especially, existing systems tend to be much more narrowband than is required for mitigating the coupled bunch instability for JLEIC. J-PARC Main Ring feedback system for intrabunch feedback looks promising, with a bandwidth about half of the JLEIC requirement, and is currently limited by the power amplifier.
• Working with S. Wang to contribute transverse feedback system requirements to the JLEIC Collaboration Meeting talk on feedback systems.

Guohui Wei

• I find a tune different between MADX and ELEGANT with detector solenoid effect. After discussing with the host of ELEGANT CODE, Michael Borland, we find the tune and twiss parameters are not correct in a ELEGANT output from a ring lattice with a coupling section. And Michael Borland agree to make an upgrade on ELEGANT in 1-2 weeks for the JLEIC lattice simulation.
• LDRD study of the geometry tagging after the collision. I study the multiplicities of n, p, d and alfa after the collision of e+208Pb at 10 x 40 GeV. Meanwhile, A,Z,p, and alfa of final state are also statistic in their multiplicities. Those two analysis are contracted with A and detected neutron at ZDC.
• I also study the decoupling in IR of ion collider ring with nested skew quads in upstream triplet. Those result have been discussed with Renuka and Mike in BP meeting.

Yuhong Zhang

• Completed a program for the JLEIC collaboration meeting
• Started preparation of slides for the collaboration meeting
• Attended telecon for bunched beam cooling, and discussed and prepared a plan
• Explored LDRD for JLEIC including small aperture magnets for high energy upgrade of the JLEIC ion collider ring
• Attended various meetings

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Computational Physics - Y. Roblin

Yves Roblin

• CEBAF
  • write technote on raytrace analysis
  • Prepare for D. turner to be matrixed during the summer
  • Review optics from CEBAF, slight dispersion leakage in vertical
• JLEIC
  • Carrying out simulations at NESRC for bbeam in the context of the FOA
  • Preparing for upcoming coll. Meeting.

He Zhang

• Mar 3 - Mar 16
  • JSPEC Development - Read a few references to understand how the electron beam space charge model is derived. Basically, there are two effects due to the space charge field. Firstly, the potential changes within the electron bunch along with the distance to the axis, which results in a change of longitudinal velocity. Second, under the effects of both the electric field caused by the space charge and the external magnetic field, electrons starts to rotate around the magnetic field line with a drift velocity. Both effects will change the ion velocity with respect to the electrons. The second effect also leads to an increase of the electron temperature. The code to calculate both effects for DC electron beam has been finished. It is under development for Gaussian beam.
  • Extend the tpsa code - Lingyun’s tpsa code is used in my fmm code for arbitrary kernel function. This code has been revised for better performance and additional function, so that we can perform some differential algebra work without using COSY Infinity. Firstly, the memory management was changed. It was changed once before for FMM usage, by allocating the memory pool for all DA vectors at the beginning instead of allocating for each DA vector when they are used for the first time. This approach significantly increased the efficiency. But in that application, the user has to manually clean the pool, otherwise the pool will be full soon and the calculation cannot continued. This is inconvenient. Now the memory pool is controlled by a linked list, which records the available memory for new DA vectors. The linked list is upgraded automatically each time when a DA vector is created or deleted. In this way, the user will never need to worry about the memory pool as long as the pool size is not too small. The efficiency of this approach is a little worse than the one in FMM, due to the operations on the linked list, but still much better than the original way. Secondly, a few functions are revised for better performance and a few functions are added, e.g. calculating an arbitrary power of a DA vector. Thirdly, the ultimate purpose is to calculate the composition of two groups of DA vectors, which is essential for DA based algorithms. The original tpsa code has this function, but it was implemented in a very naïve way with bad efficiency. A group of functions have been added, including subscribing one base in a DA vector by a real number, subscribing one base in a DA vector by a DA vector, subscribing all bases in a DA vector by a group of DA vectors, composition of two groups of DA vectors, composition of a group of DA vectors with a group of real numbers (tracking with a DA map). Finally, a wrapper is added with overloaded operators, so that one can use the DA vectors as basic data types. The development is almost done. Most functions have been finished and tested with COSY Infinity. I need to test two more functions and document the code.
  • Update on the kernel independent FMM - Updated the DA package used in the kernel independent FMM code by adding moving constructor and revising the operator overloading. The efficiency was improved for about 3%. Now I think the code is good enough for demonstrating the idea. I will start generating data and preparing a paper on it.
  • Others - Reviewed four papers.
• Mar 17 - Mar 30
  • Cooling parameters were changed slightly as I was notified. I will do some simulation with the new parameters for the coming collaboration meeting.
  • Prepare for my talk in the collaboration meeting.
  • Revise the FMM paper.
  • Review two more papers. (I feel the reviews took too much time. I’m going to control the number of papers below two per month, after I finish those at ha

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Diagnostic Development - K. Jordan

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LERF - S. Benson

• March 5-16
  • Finished preparing two talks for JLEIC collaboration meeting, partially complete with a third.
  • Updated GTS laser training course materials and derived a new course for non-laser users
  • Hosted cooler ring meetings on March 7, and 14 and wrote up minutes
  • Numerology tech note awaiting input from Jiquan
  • Made some progress in deriving solenoid specifications for Cooler. Trying to understand how to extrapolate.
  • Completed MED01, Rad worker I, and Safety Observation training
  • Looked at THz FEL specifications for HZDR.
  • Assisted Michelle Shinn in clearing out boxes from the LERF and recovering files from her old computers.
• March 19-30
  • Complete and Review Collaboration talks and present them
  • Attend the collaboration meeting
  • Continue to derive solenoid specifications for Cooler
  • Start to derive new ICRADA details for HZDR collaboration