IPAC2018 - List of Authors (Wang, H.)

Paper	Title	Page
MOPMK015	Development of a Bunched-Beam Electron Cooler for the Jefferson Lab Electron-Ion Collider	382
	S.V. Benson, Y.S. Derbenev, D. Douglas, F.E. Hannon, A. Hutton, R. Li, R.A. Rimmer, Y. Roblin, C. Tennant, H. Wang, H. Zhang, Y. Zhang JLab, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S.DOE Contract No. DE-AC05-06OR23177. Jefferson Lab is in the process of designing an electron-ion collider with unprecedented luminosity at a 65 GeV center-of-mass energy. This luminosity relies on ion cooling in both the booster and the storage ring of the accelerator complex. The cooling in the booster will use a conventional DC cooler similar to the one at COSY. The high-energy storage ring, operating at a momentum of up to 100 GeV/nucleon, requires novel use of bunched-beam cooling. We will present a new design for a Circulator Cooler Ring for bunched-beam electron cooling. This requires the generation and transport of very high-charge magnetized bunches, acceleration of the bunches in an energy recovery linac, and transfer of these bunches to a circulating ring that passes the bunches 11 times through the proton or ion beam inside cooling solenoids. This design requires the suppression of the effects of space charge and coherent synchrotron radiation using shielding and RF compensation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMK015
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MOPMK017	Transient Beam Loading Due to the Bunch Train Gap and Its Compensation Experiments at BEPC-II and ALS	390
	H. Wang, R.A. Rimmer, S. Wang JLab, Newport News, Virginia, USA J.P. Dai, Q. Qin, J. Xing, J.H. Yue, Y. Zhang IHEP, Beijing, People's Republic of China D. Teytelman Dimtel, San Jose, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Non-uniform bunch fill patterns in storage rings, driven by the need to provide gaps for beam aborting and ion clearing cause a large beam loading change in the RF cavities. The induced turn-periodic transient in the cavity voltage modulates longitudinal beam properties along the train, such as synchronous position and bunch length. In the EIC design, due to the asymmetric bunch train structure between the electron and the ion beam, such modulation results in shifting collision point and leads to reduced luminosity. We have carried out the beam based experiments at BEPC-II and ALS using bunch-by-bunch diagnostic capabilities of the coupled-bunch feedback systems to study this transient effect. A modulated bunch filling pattern with higher charge density around the gap has been demonstrated to be effective in partially compensating this transient modulation. Details of the experimental setups and the data analysis will be presented to this conference.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMK017
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TUPAL068	The Development of a Nw Fast Harmonic Kicker for the JLEIC Circulator Cooling Ring	1171
	G.-T. Park, F. Fors, J. Guo, R.A. Rimmer, H. Wang, S. Wang JLab, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. After the first half-scale, 5 harmonic kicker cavity prototyping * for the JLEIC's CCR/ERL electron cooler and the beam dynamic simulation study of the 10-turn CCR *. The optimized circulation cooling turns has been changed to 11 and only 5 odd-harmonic modes from 86.6 MHz to 779.4 MHz plus a DC bias are needed for the harmonic RF kicker system. The new cavity design including the electromagnetic and thermal cooling optimization and its 11 turns beam bunch tracking simulation with the new numerology of RF deflecting voltages will be presented. Further design specifications for its RF harmonic drive and the broadband RF window, coupler and circulator component will be given for handling 5 kW of total RF power. Y, Huang, H. Wang et al., Physical Review Accelerators and Beams 19, 122001 (2016). ** Y. Huang, H. Wang et al., Physical Review Accelerators and Beams 19, 084201 (2016).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL068
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TUPAL069	Experimental Demonstration of Ion Beam Cooling with Pulsed Electron Beam	1174
	Y. Zhang, A. Hutton, K. Jordan, T. Powers, R.A. Rimmer, M. F. Spata, H. Wang, S. Wang, H. Zhang JLab, Newport News, Virginia, USA J. Li, X.M. Ma, L.J. Mao, M.T. Tang, J.C. Yang, X.D. Yang, H. Zhao, H.W. Zhao IMP/CAS, Lanzhou, People's Republic of China
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. Cooling ion beams at high energy is presently considered for several ion colliders, in order to achieve high luminosities by enabling a significant reduction of emittance of hadron beams. Electron beam at cooling channel in a few to tens MeV can be accelerated by a RF/SRF linac, and thus using bunched electrons to cool bunched ions. To study such cooling process, the DC electron gun of EC35 cooler at the storage ring CSRm, IMP was modified by pulsing the grid voltage. A 0.07-3.5 micro-second pulse length with a repetition frequency of less than 250 kHz and synchronized with the ion revolution frequency was obtained. The first experimental demonstration of cooling of a coasting and bunched ion beam by a pulsed electron beam was carried out. Data analysis indicates the bunch length shrinkage and the momentum spread reduction of bunched 12C+6 ion beam as evidence of cooling. A longitudinal grouping effect of the coasting ion beam by the electron pulses has also been observed. In this paper, we will present experimental results and comparison to the simulation modelling, particularly on the bunched electron cooling data after carefully analyzing the beam diagnostic signals. L.J. Mao et al., Experimental Demonstration of Electron Cooling with Bunched Electron Beam, TUP15, Proceedings of COOL2017, Bonn, Germany
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAL069
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TUPMF034	Measuring the Electrical Center and Field Flatness of 704 MHz Deflecting Cavity for LEReC with Wire Stretching System	1320
	T. Xin, J.M. Brennan, J.C.B. Brutus, K. Mernick, K.S. Smith, B. P. Xiao, A. Zaltsman BNL, Upton, Long Island, New York, USA W. Johnson SBU, Stony Brook, New York, USA H. Wang JLab, Newport News, Virginia, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. 704 MHz deflecting cavity was designed for the Low Energy RHIC electron Cooling (LEReC) project. The cavity will serve as a major component in diagnostic line. In LEReC project the requirement on the energy spread of the electron beam is extremely high (better than 10^-4) and the diagnostic system has to to be designed accordingly. The 704 MHz transverse deflecting cavity provides the vertical kick to the beam after it passes through the dispersion dipole so that we can measure the energy spread of the core of the bunch. Traditional way of determining the electrical center of the cavity involves the needle pulling and integration of the signal which is prone to the cumulative error. We present the measurement result from a wire stretching system that is much more efficient and accurate compared to the bead/needle pulling method. Both simulation and experimental results are shown in this paper and the potential in further application is discussed at the end.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF034
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THPAL042	Injection Locked 1497 MHz Magnetron	3736
	M.L. Neubauer, A. Dudas, S.A. Kahn Muons, Inc, Illinois, USA R.A. Rimmer, H. Wang JLab, Newport News, Virginia, USA
	A novel injection-locked 1497 MHz 13 kW AM magnetron design is presented. The anode design to minimized eddy currents due to the changing magnetic field is presented. Thermal calculations of two design options are also presented. An extra degree of freedom in the anode construction is made possible by the fact that the magnetron is injection locked. This fact presents some additional design details that can be utilized in the cooling network for the magnetron anode.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL042
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THPAL144	952.6 MHz SRF Cavity Development for JLEIC	3982
	R.A. Rimmer, W.A. Clemens, F. Fors, J. Guo, F.E. Hannon, J. Henry, F. Marhauser, L. Turlington, H. Wang, S. Wang JLab, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177 JLab is developing new SRF cavity designs at 952.6 MHz for the proposed Jefferson Lab Electron-Ion Collider (JLEIC). New cavities will be required for the ion ring, cooler ERL and booster and eventually for an upgrade of the electron ring to allow the highest possible bunch collision rate. The challenges include the need for high fundamental mode power couplers and strong HOM damping, with high HOM power capability. Initial focus is on the cooler ERL 5-cell cavity as this is a critical component for the strong, high energy, bunched-beam cooling concept. 1-cell and 5-cell Nb prototype cavities have been designed and fabricated. Details concerning the cavity fabrication and test results will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL144
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THPAL145	Magnetron R&D toward the Amplitude Modulation Control for SRF Accelerator	3986
	R.A. Rimmer, T. E. Plawski, H. Wang JLab, Newport News, Virginia, USA A. Dudas, S.A. Kahn, M.L. Neubauer Muons, Inc, Illinois, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177 and SBIR grant DE-SC0013203 The scheme of using a high efficiency magnetron to drive a superconducting radio frequency (SRF) accelerator cavity needs not only the injection phase locking but also the amplitude modulation to compensate the cavity's microphomics caused cavity voltage change and the beam loading variation. To be able to do a fast and efficient modulation, the magnetron's magnetic field has to be trimmed by an external coil to compensate the frequency pushing effect due to the anode current change [1]. A low eddy current magnetron body has been designed and built [2]. This paper will present the analytical prediction, simulation and experimental results on the 2.45 GHz magnetron test stand with the modulation frequency up to 1 kHz. In addition, the progresses on the injection lock to a copper cavity, new 1497 MHz magnetron prototype, 13 kW high power magnetron test stand development and newly built low level RF (LLRF) controller for the amplitude modulation will be reported. [1] M. Neubauer et al, THPIK123, Proceedings of IPAC 2017, Copenhagen, Denmark [2] S. A. Kahn et al, THPIK121, Proceedings of IPAC 2017, Copenhagen, Denmark
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THPML095	Improvement of Wire-Stretching Technique to the RF Measurements of E-Center and Multipole Field for the Dipole Cavities	4885
	G.-T. Park, J. Guo, H. Wang JLab, Newport News, Virginia, USA A. Overstreet ODU, Norfolk, Virginia, USA B. P. Xiao, T. Xin BNL, Upton, Long Island, New York, USA
	Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. After the first publication* of wire-stretching technique from its principle to measure the electrical center of a deflecting cavity, more refinements of this techniques including the review of its analytical and simulation results, RF circuit improvement to improve the signal to noise ratio and its application to other cavities have been developed. These applications include the electrical center measurements for the LHC RFD and DQW crabbing cavity prototypes, multi-frequency harmonic kicker cavity for JLEIC electron cooler, TE011 cavity developed for the beam magnetization measurement, and a separator cavity at BNL**. Further development of measurement calibration, error reduction, alignment of cavity installation to the machine beam line, and multipole field analysis for the beam dynamics will be presented. H. Wang, Proceedings of NAPAC2016, pp225-228 S. A. Overstreet, BS Thesis 2017, Guilford College, Greensboro, NC J. Guo et al. these proceedings ***T. Xin et al, these proceedings
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML095
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THPML096	A Non-Invasive Magnetic Momentum Monitor Using a TE011 Cavity	4889
	J. Guo, J. Henry, M. Poelker, R.A. Rimmer, R. Suleiman, H. Wang JLab, Newport News, Virginia, USA
	Funding: Authored by Jefferson Science Associates, LLC with Laboratory Directed Research and Development funding, under U.S. DOE Contract No. DE-AC05-06OR23177. The Jefferson Lab Electron-Ion Collider (JLEIC) design relies on cooling of the ion beam with bunched electron beam. The bunched beam cooler complex consists of a high current magnetized electron source, an energy recovery linac, a circulating ring, and a pair of long solenoids where the cooling takes place. A non-invasive real time monitoring system is highly desired to quantify electron beam magnetization. The authors propose to use a passive copper RF cavity in TE011 mode as such a monitor. In this paper, we will show the mechanism and scaling law of this device, as well as the design and testing results of the prototype cavity.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML096
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Paper

Title

Page

Development of a Bunched-Beam Electron Cooler for the Jefferson Lab Electron-Ion Collider

382

S.V. Benson, Y.S. Derbenev, D. Douglas, F.E. Hannon, A. Hutton, R. Li, R.A. Rimmer, Y. Roblin, C. Tennant, H. Wang, H. Zhang, Y. Zhang
JLab, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S.DOE Contract No. DE-AC05-06OR23177.
Jefferson Lab is in the process of designing an electron-ion collider with unprecedented luminosity at a 65 GeV center-of-mass energy. This luminosity relies on ion cooling in both the booster and the storage ring of the accelerator complex. The cooling in the booster will use a conventional DC cooler similar to the one at COSY. The high-energy storage ring, operating at a momentum of up to 100 GeV/nucleon, requires novel use of bunched-beam cooling. We will present a new design for a Circulator Cooler Ring for bunched-beam electron cooling. This requires the generation and transport of very high-charge magnetized bunches, acceleration of the bunches in an energy recovery linac, and transfer of these bunches to a circulating ring that passes the bunches 11 times through the proton or ion beam inside cooling solenoids. This design requires the suppression of the effects of space charge and coherent synchrotron radiation using shielding and RF compensation.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMK015

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MOPMK017

Transient Beam Loading Due to the Bunch Train Gap and Its Compensation Experiments at BEPC-II and ALS

390

H. Wang, R.A. Rimmer, S. Wang
JLab, Newport News, Virginia, USA
J.P. Dai, Q. Qin, J. Xing, J.H. Yue, Y. Zhang
IHEP, Beijing, People's Republic of China
D. Teytelman
Dimtel, San Jose, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
Non-uniform bunch fill patterns in storage rings, driven by the need to provide gaps for beam aborting and ion clearing cause a large beam loading change in the RF cavities. The induced turn-periodic transient in the cavity voltage modulates longitudinal beam properties along the train, such as synchronous position and bunch length. In the EIC design, due to the asymmetric bunch train structure between the electron and the ion beam, such modulation results in shifting collision point and leads to reduced luminosity. We have carried out the beam based experiments at BEPC-II and ALS using bunch-by-bunch diagnostic capabilities of the coupled-bunch feedback systems to study this transient effect. A modulated bunch filling pattern with higher charge density around the gap has been demonstrated to be effective in partially compensating this transient modulation. Details of the experimental setups and the data analysis will be presented to this conference.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMK017

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TUPAL068

The Development of a Nw Fast Harmonic Kicker for the JLEIC Circulator Cooling Ring

1171

G.-T. Park, F. Fors, J. Guo, R.A. Rimmer, H. Wang, S. Wang
JLab, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
After the first half-scale, 5 harmonic kicker cavity prototyping * for the JLEIC's CCR/ERL electron cooler and the beam dynamic simulation study of the 10-turn CCR **. The optimized circulation cooling turns has been changed to 11 and only 5 odd-harmonic modes from 86.6 MHz to 779.4 MHz plus a DC bias are needed for the harmonic RF kicker system. The new cavity design including the electromagnetic and thermal cooling optimization and its 11 turns beam bunch tracking simulation with the new numerology of RF deflecting voltages will be presented. Further design specifications for its RF harmonic drive and the broadband RF window, coupler and circulator component will be given for handling 5 kW of total RF power.
* Y, Huang, H. Wang et al., Physical Review Accelerators and Beams 19, 122001 (2016).
** Y. Huang, H. Wang et al., Physical Review Accelerators and Beams 19, 084201 (2016).

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TUPAL069

Experimental Demonstration of Ion Beam Cooling with Pulsed Electron Beam

1174

Y. Zhang, A. Hutton, K. Jordan, T. Powers, R.A. Rimmer, M. F. Spata, H. Wang, S. Wang, H. Zhang
JLab, Newport News, Virginia, USA
J. Li, X.M. Ma, L.J. Mao, M.T. Tang, J.C. Yang, X.D. Yang, H. Zhao, H.W. Zhao
IMP/CAS, Lanzhou, People's Republic of China

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
Cooling ion beams at high energy is presently considered for several ion colliders, in order to achieve high luminosities by enabling a significant reduction of emittance of hadron beams. Electron beam at cooling channel in a few to tens MeV can be accelerated by a RF/SRF linac, and thus using bunched electrons to cool bunched ions. To study such cooling process, the DC electron gun of EC35 cooler at the storage ring CSRm, IMP was modified by pulsing the grid voltage. A 0.07-3.5 micro-second pulse length with a repetition frequency of less than 250 kHz and synchronized with the ion revolution frequency was obtained. The first experimental demonstration of cooling of a coasting and bunched ion beam by a pulsed electron beam was carried out. Data analysis indicates the bunch length shrinkage and the momentum spread reduction of bunched 12C+6 ion beam as evidence of cooling. A longitudinal grouping effect of the coasting ion beam by the electron pulses has also been observed*. In this paper, we will present experimental results and comparison to the simulation modelling, particularly on the bunched electron cooling data after carefully analyzing the beam diagnostic signals.
* L.J. Mao et al., Experimental Demonstration of Electron Cooling with Bunched Electron Beam, TUP15, Proceedings of COOL2017, Bonn, Germany

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TUPMF034

Measuring the Electrical Center and Field Flatness of 704 MHz Deflecting Cavity for LEReC with Wire Stretching System

1320

T. Xin, J.M. Brennan, J.C.B. Brutus, K. Mernick, K.S. Smith, B. P. Xiao, A. Zaltsman
BNL, Upton, Long Island, New York, USA
W. Johnson
SBU, Stony Brook, New York, USA
H. Wang
JLab, Newport News, Virginia, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
704 MHz deflecting cavity was designed for the Low Energy RHIC electron Cooling (LEReC) project. The cavity will serve as a major component in diagnostic line. In LEReC project the requirement on the energy spread of the electron beam is extremely high (better than 10^-4) and the diagnostic system has to to be designed accordingly. The 704 MHz transverse deflecting cavity provides the vertical kick to the beam after it passes through the dispersion dipole so that we can measure the energy spread of the core of the bunch. Traditional way of determining the electrical center of the cavity involves the needle pulling and integration of the signal which is prone to the cumulative error. We present the measurement result from a wire stretching system that is much more efficient and accurate compared to the bead/needle pulling method. Both simulation and experimental results are shown in this paper and the potential in further application is discussed at the end.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF034

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THPAL042

Injection Locked 1497 MHz Magnetron

3736

M.L. Neubauer, A. Dudas, S.A. Kahn
Muons, Inc, Illinois, USA
R.A. Rimmer, H. Wang
JLab, Newport News, Virginia, USA

A novel injection-locked 1497 MHz 13 kW AM magnetron design is presented. The anode design to minimized eddy currents due to the changing magnetic field is presented. Thermal calculations of two design options are also presented. An extra degree of freedom in the anode construction is made possible by the fact that the magnetron is injection locked. This fact presents some additional design details that can be utilized in the cooling network for the magnetron anode.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL042

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THPAL144

952.6 MHz SRF Cavity Development for JLEIC

3982

R.A. Rimmer, W.A. Clemens, F. Fors, J. Guo, F.E. Hannon, J. Henry, F. Marhauser, L. Turlington, H. Wang, S. Wang
JLab, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177
JLab is developing new SRF cavity designs at 952.6 MHz for the proposed Jefferson Lab Electron-Ion Collider (JLEIC). New cavities will be required for the ion ring, cooler ERL and booster and eventually for an upgrade of the electron ring to allow the highest possible bunch collision rate. The challenges include the need for high fundamental mode power couplers and strong HOM damping, with high HOM power capability. Initial focus is on the cooler ERL 5-cell cavity as this is a critical component for the strong, high energy, bunched-beam cooling concept. 1-cell and 5-cell Nb prototype cavities have been designed and fabricated. Details concerning the cavity fabrication and test results will be presented.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL144

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THPAL145

Magnetron R&D toward the Amplitude Modulation Control for SRF Accelerator

3986

R.A. Rimmer, T. E. Plawski, H. Wang
JLab, Newport News, Virginia, USA
A. Dudas, S.A. Kahn, M.L. Neubauer
Muons, Inc, Illinois, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177 and SBIR grant DE-SC0013203
The scheme of using a high efficiency magnetron to drive a superconducting radio frequency (SRF) accelerator cavity needs not only the injection phase locking but also the amplitude modulation to compensate the cavity's microphomics caused cavity voltage change and the beam loading variation. To be able to do a fast and efficient modulation, the magnetron's magnetic field has to be trimmed by an external coil to compensate the frequency pushing effect due to the anode current change [1]. A low eddy current magnetron body has been designed and built [2]. This paper will present the analytical prediction, simulation and experimental results on the 2.45 GHz magnetron test stand with the modulation frequency up to 1 kHz. In addition, the progresses on the injection lock to a copper cavity, new 1497 MHz magnetron prototype, 13 kW high power magnetron test stand development and newly built low level RF (LLRF) controller for the amplitude modulation will be reported.
[1] M. Neubauer et al, THPIK123, Proceedings of IPAC 2017, Copenhagen, Denmark
[2] S. A. Kahn et al, THPIK121, Proceedings of IPAC 2017, Copenhagen, Denmark

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THPML095

Improvement of Wire-Stretching Technique to the RF Measurements of E-Center and Multipole Field for the Dipole Cavities

4885

G.-T. Park, J. Guo, H. Wang
JLab, Newport News, Virginia, USA
A. Overstreet
ODU, Norfolk, Virginia, USA
B. P. Xiao, T. Xin
BNL, Upton, Long Island, New York, USA

Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
After the first publication* of wire-stretching technique from its principle to measure the electrical center of a deflecting cavity, more refinements of this techniques including the review of its analytical and simulation results, RF circuit improvement to improve the signal to noise ratio and its application to other cavities have been developed. These applications include the electrical center measurements for the LHC RFD and DQW crabbing cavity prototypes, multi-frequency harmonic kicker cavity for JLEIC electron cooler**, TE011 cavity developed for the beam magnetization measurement***, and a separator cavity at BNL****. Further development of measurement calibration, error reduction, alignment of cavity installation to the machine beam line, and multipole field analysis for the beam dynamics will be presented.
*H. Wang, Proceedings of NAPAC2016, pp225-228
**S. A. Overstreet, BS Thesis 2017, Guilford College, Greensboro, NC
***J. Guo et al. these proceedings
****T. Xin et al, these proceedings

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THPML096

A Non-Invasive Magnetic Momentum Monitor Using a TE011 Cavity

4889

J. Guo, J. Henry, M. Poelker, R.A. Rimmer, R. Suleiman, H. Wang
JLab, Newport News, Virginia, USA

Funding: Authored by Jefferson Science Associates, LLC with Laboratory Directed Research and Development funding, under U.S. DOE Contract No. DE-AC05-06OR23177.
The Jefferson Lab Electron-Ion Collider (JLEIC) design relies on cooling of the ion beam with bunched electron beam. The bunched beam cooler complex consists of a high current magnetized electron source, an energy recovery linac, a circulating ring, and a pair of long solenoids where the cooling takes place. A non-invasive real time monitoring system is highly desired to quantify electron beam magnetization. The authors propose to use a passive copper RF cavity in TE011 mode as such a monitor. In this paper, we will show the mechanism and scaling law of this device, as well as the design and testing results of the prototype cavity.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML096

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