2018-03-30

Director - M. Spata No report. Acting Accelerator Division Head

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Accelerator Physics - T. Satogata

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Accelerator R and D - Y. Zhang
Fanglei Lin

• Continued single particle nonlinear dynamics study for the electron ring.
• Prepared and presented a talk at the JLEIC spring collaboration meeting.
• Investigating JLEIC collider rings’ geometry to fit in the Jlab site.
• Miscellaneous: attended JLEIC general meeting.

Vasiliy Morozov Mar 17 - Mar 30

• Preparation for and participation in the JLEIC collaboration meeting
• Work on a new version of the ion collider ring design
• Polarization: teleconference with Anatoliy's group and discussion of an optimized electron spin rotator
• Revising the scopes and budgets of both funded and unfunded FOA proposals
• Detector design: work on the ion orbit correction scheme
• Geometry tagging LDRD: teleconference with collaborators

Mar 31 - Apr 13

• Reducing the collider ring circumference
• Preparation of two talks for DIS'18
• Preparation of two papers for IPAC'18

Amy Sy

• Set up WARP simulation environment to model two counter-propagating magnetized beams; considering the effect of one interaction between the beams at some point along the accelerating path, but not necessarily in an accelerating field. Implementing diagnostics to track particles that cross specified longitudinal planes to evaluate emittance growth. Setting up proper simulation weights and collision operators. Discussions with Slava on compensation of transverse kick applied to the accelerating beam by setting proper phase of a second kick, such that the induced Larmor rotations cancel out.
• Worked with S. Wang to contribute slides on transverse feedback systems relevant to the ion ring for his talk on feedback system requirements at the JLEIC Spring 2018 Collaboration Meeting.
• Participated in the JLEIC Spring 2018 Collaboration Meeting.
• Reviewed polarized ion source requirements and resonant charge-exchange ionization for a discussion on a possible LDRD proposal on a laser driven polarized D- source for JLEIC.

Guohui Wei

• Prepared report of "Dynamic Aperture and Detector Solenoid Compensation" for the JLEIC Collaboration Meeting Spring 2018. And presented it on Tuesday, 27 March 2018
• LDRD study of the geometry tagging after the collision. An alternative method to measuring the evaporation neutrons is to detect the residual nucleus. Measuring its magnetic rigidity (~ A/Z), is straightforward as it changes substantially for nuclei that evaporate many neutrons. Detection extremely close to the beam is not needed.
• I continue to study the decoupling in IR of ion collider ring with nested skew quads in upstream triplet. an effect analogous to quadrupole rotation can be dynamically produced by appropriately combining a normal quadrupole component (strength: kn) and a skew component (strength: ks).

Yuhong Zhang

• Organized the JLEIC collaboration meeting, gave 3 talks
• Gave a presentation in JLEIC general meeting
• Attended cooling experiment teleconference
• Prepared slides for an invited talk at APS meeting
• Explored a LDRD for small aperture magnets for JLEIC

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Computational Physics - Y. Roblin

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Diagnostic Development - K. Jordan

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LERF - S. Benson
March 19-30

• Prepared and presented three talks at the Collaboration meeting
• Attended the collaboration meeting.
• Made some good progress in deriving the specifications for the cooler ring solenoid
• Started to go over the details of the CeC micro bunching proposal that was funded.
• Had some discussions with P. Evtushenko about HZDR upgrade.
• Worked out some property issue for G Biallas and D. Douglas to make sure their property was properly transferred.

April 2-13

• Prepare for and attend the FACET II Director's review at SLAC April 10-11.
• Continue to derive the specifications for the Cooler ring solenoid.
• Host Cooler ring meeting on April 4th.
• Lay out the cooler ring section of the preCDR in more detail. Decide on near term tasks.