2018-07-06

Director - M. Spata
No report. Accelerator Division Office.

---

Accelerator Physics - T. Satogata (Interim CASA Department Head)
Todd Satogata

  Previous two weeks (June 25-July 6)
     - JLEIC: pCDR writing, template, EIC lunch, impedance/HE/R&D meetings
     - JLEIC: Peter McIntyre meeting (Jun 26)
     - JLEIC: Summer student work on Booster simulations, training
     - JACoW: JBoD telecon (Jun 29), post/review meeting minutes
     - ADMIN: Leadership/group meetings, staffing input and planning
     - ADMIN: Director Ops review (Jun 26-28)
     - ODU: Continue Randy advising, dissertation draft finalization
  Next two weeks (July 9-July 20)
     - ADMIN: Leadership/group meetings, staffing input and planning
     - ADMIN: Audrey move transition, Li-Shi meeting (Jul 16)
     - JLEIC: pCDR writing, template, EIC lunch, impedance/HE/R&D meetings
     - JLEIC: Complete Booster vacuum tech note calculations
     - JLEIC: Summer student work on Booster simulations, training
     - IPAC18: Finalize proceedings, IPAC'18 delegate survey report
     - JACoW: Publishing script updates, fix PDF index of PAC'95
     - ODU: Randy PhD defense (Jul 12)

Alex Bogacz

   Previous two weeks (June 25-July 6)
     - PERLE: Attend PERLE collaboration meeting (Jun 26, Orsay)
     - PERLE: Attend LHeC/FCCeh/PERLE workshop (Jun 27-29, Orsay)
     - PERLE: Present two talks at above meetings
     - ADMIN: Attend ARIES Muon Collider Workshop (Jul 1-3, Padova)
     - ADMIN: Present two talks at ARIES Muon Collider Workshop
   Next two weeks (July 9-July 20)
     - VACATION: Jul 9-Jul 13
     - ADMIN: Phys Rev Accel Beams paper review

Rui Li

   Previous two weeks (June 25-July 6)
     - JLEIC: Presented the LCBI for Frank's new HOM coupler design at
       the impedance meeting.
     - JLEIC: Assessment of the behavior of collective effects in
       higher current regime of e-beam (E>10GeV), in responding to
       Yuhong's question for the high-energy JLEIC.
     - JLEIC: Collected the e-ring new parameters from Fanglei,
       Vasiliy will later send me new parameters for the p-ring. These
       may change the behavior of LCBI which is very sensitive to
       parameters.
     - JLEIC: Calculated growth time for the transverse coupled bunch
       instability (TCBI) for Frank's new HOM design using ZAP, and
       see no improvement of the growth rate for the new HOM coupler
       design from that of the old one.
     - JLEIC: Working on the Mathematica calculation of TCBI, so as to
       identify the HOM resonance that gives dominant contribution to
       growth rate, so the RF people can work on mitigation of these
       HOM.
   Next two weeks (July 9-July 20)
     - JLEIC: Finish my part of the ICFA newsletter writing
     - JLEIC: Continue to finish the Mathematica calculation of TCBI
       and its comparison with ZAP
     - JLEIC: Summarize the LCBI and TCBI results for exchange with
       the RF people
     - JLEIC: Estimate the resistive wall impedance in JLEIC e-ring
       and ion ring

Edy Nissen

   Previous two weeks (June 25-July 6)
     - JLEIC: Answered LDRD questions posed by reviewers
     - JLEIC: Created presentation slides for LDRD review
     - JLEIC: Determined that the acceleration anomaly in synergia is
       caused by space charge, not bucket shape changes or higher order
       nonlinear dispersions.
     - JLEIC: Gave LDRD Presentation
     - VACATION: June 25, July 2-3
   Next two weeks (July 9-July 20)
     - JLEIC: Work on booster working point simulations to eliminate
       the acceleration anomaly
     - JLEIC: Work with summer student on injection modeling for the
       booster

Chris Tennant

   Previous two weeks (June 25-July 6)
     - VACATION: July 5-6
     - JLEIC: working through issues with cooler to get a consistent S2E
     - JLEIC: re-tune ERL arc to accept longer bunch from injector
     - JLEIC: mBI analysis of cooler "Simple Arc"
     - PERLE: wrap up PERLE TN
   Next two weeks (July 9-July 20)
     - VACATION:  July 16-19
     - JLEIC: seek counsel for path forward with S2E
     - JLEIC: pCDR writing

---

Accelerator R & D - Y. Zhang

---

Computational Physics - Y. Roblin
Kirsten Deitrick:

• Last two weeks:
  • Magnetized beam (LEFR PoP):

  -correct magnetization damage after FEL booster with off-axis travel through skew quad (prepping to run/optimize on cluster)

  -start looking at magnetization preservation through merger designs

  • Straight Merger at CBETA:

  -finish data analysis

  -begin simulations

  -present preliminary results in JLEIC R&D meeting

  • eCloud:

  -finish text for preCDR

  -get other cold section magnet properties from Vasiliy/Fanglei

  • Impedance:

  -best/worst case for electron ring impedance scenario

  -meeting (present above + feedback kickers in various machines)

  • Meetings:

  -Impedance

  -Cooler (x2)

  -JLEIC (x1)

  • Misc:

  -DOE Travel to China brief reading

  -Introduction for Summer Lecture Series (x2), subbing for Geoff Krafft

  -Raemaad GPT help (Geoff's student)

• Next two weeks:
  • Magnetized beam (LERF PoP):

  -look at 3D FEL booster optimization results

  -magnetization preservation through merger designs

  • Straight Merger at CBETA:

  -continue simulations

  -explain discrepancies (qualitative behavior matches relatively well)

  • eCloud:

  -simulate eCloud in quad/sextupole/drift of ion ring using provided parameters (mostly to show density highest in dipoles)

  • Meetings:

  -Cooler (x2)

  -JLEIC (x2)

Yves Roblin:

• Vacation 7/2 -7/6
• JLEIC:

  -pCDR writing

  -ICFA paper writing

  -gear changing simulations

• CEBAF:

  -Bteam

  -prepare ATLIS for August half pass run

  -meeting with Hall A to discuss schedule for the half pass into hall A

  -APEX procedural development and planning

  -model improvement, redoing all the arcs with proper K1 and constraints

• Next two weeks:
• JLEIC:

  -pCDR

  -report for FOA 17 supplemental

• CEBAF:

  -model work, coordinating activity for restart

  -preparing for July 26th OPS prestart talk

Dennis Turner:

• Last two weeks:
  • Presented ced2elegant and ArcSteer to BTeam 6/26
  • ArcSteer:

  -Odds and ends from BTeam discussions.

  -Completed templates for all 10 arcs and 0R.

  • rayTrace:

  -Discussed requirements with Tief and Yves.

  -Began work on data collection. Studied existing rayTrace code.

  • Minor bugfixes and documentation updates for ced2elegant, etc.
• Out of town 6/29 to 7/1.
• Sick 7/2 to 7/3.
• Holiday 7/4.
• Next two weeks:
  • Continue work on rayTrace.
  • Continue to get dispersionTool ready for further testing and release.
  • Test ArcSteer in 0R if the opportunity arises.

He Zhang:

• JSPEC Development

Tested the codes that calculates the electron charge density inside an arbitrary electron bunch. The electron bunch is represented by two million particles, which are generated randomly with Gaussian distribution. The electron are loaded into memory and then distributed into a tree structure of boxes. The maximum number of electrons in each childless box is adjustable. This process only needs to be performed once as long as the electron charge distribution is assumed unchanged during the cooling process. The ions are put into a regular grid and the grid density is adjustable. (A regular grid is used only for testing purpose. In real simulation, ions can have any distribution.) Ions are distributed into the boxes and the charge density around the ion is calculated by the electron number inside the box divided by the box volume. Electron density is plotted for a few different grid sizes and the results show the algorithm works as expected. Numerical noises are noticed in the electron density calculation, which is as expected, and the noises reduce as the grid size becomes smaller. Now it is still not clear how much it will affect the cooling rate calculation. It will be tested later.

I am working on fitting the above electron density calculation code into JSPEC for cooling simulations. It needs more changes in the code than I originally expected. A new model of the electron beam has been added. But several interfaces between several modules have to be revised, because in this model the relative electron speed and temperature can change. The UI needs to be updated, too. This work is still in process.

• Others

  -pCDR writing: Converted the previous writing into Latex and edited it again.

  -ICFA writing: Wrote about mulita-stage cooling strategy and cooling simulation results for both the proton beam and lead ion beam, based on my IPAC’18 paper and pCDR writing.

  -Tech report: I am writing a tech report about the TPSA/DA package that I developed based on Dr. Lingyun Yang’s code.

  -ICAP trip is approved. I was told by Prof. Berz that my talk should be arranged in the first two days. I plan to stay two nights there.

  -NERSC account: submitted the NERSC AUP, trying to re-activate my account.

  -Reviewed a paper for SIVP.

• Work plan in the following two weeks

  -Continue writing and polishing the pCDR report

  -Test, finish, and document the JSPEC package of cooling with arbitrary electron beam

  -Test the turn-by-turn tracking packge for JSPEC.

---

Diagnostic Development - K. Jordan

---

LERF - S. Benson