NAPAC2022 - Classification: 04: Hadron Accelerators

Paper	Title	Page
MOPA19	The Effect of the Main Injector Ramp on the Recycler	90
	N. Chelidze, R. Ainsworth, K.J. Hazelwood Fermilab, Batavia, Illinois, USA
	The Recycler and Main Injector are part of the Fermilab Accelerator complex used to deliver a high power proton beam. Both machines share the same enclosure with the Recycler mounted 6 ft above the Main Injector. The Main Injector accelerates beam from 8 GeV to 120 GeV. While the majority of the Recycler has mu metal shielding, the effect of the Main Injector ramp is still significant and can affect both the tunes and the orbit. In this paper, we detail the size of these effects.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA19
About •	Received ※ 02 August 2022 — Accepted ※ 04 August 2022 — Issue date ※ 23 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA05	An H⁻ Injector for the ESS Storage Ring	357
	V.G. Dudnikov, M.A. Cummings, M. Popovic Muons, Inc, Illinois, USA
	H⁻ charge exchange (stripping) injection into the European Spallation neutron Source (ESS) Storage Ring requires a 90 mA H⁻ ion source that delivers 2.9 ms pulses at 14 Hz repetition rate (duty factor ~4%) that can be extended to 28 Hz (df 8%). This can be achieved with a magnetron surface plasma H⁻ source (SPS) with active cathode and anode cooling. The Brookhaven National Laboratory (BNL) magnetron SPS can produce an H⁻ beam current of 100 mA with about 2 kW discharge power and can operate up to 0.7 % duty factor (average power 14 W) without active cooling. We describe how active cathode and anode cooling can be applied to the BNL source to increase the average discharge power up to 140 W (df 8%) to satisfy the needs of the ESS. We also describe the use of a short electrostatic LEBT as is used at the Oak Ridge National Laboratory Spallation Neutron Source to improve the beam delivery to the RFQ.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA05
About •	Received ※ 02 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 04 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA48	Effect of Lattice Misalignments on Beam Dynamics in LANSCE Linear Accelerator	455
	Y.K. Batygin, S.S. Kurennoy LANL, Los Alamos, New Mexico, USA
	Funding: Work supported by US DOE under contract 89233218CNA000001 Accelerator channel misalignments can significantly affect beam parameters in long linear accelerators. Measurements of misalignments of the LANSCE linac lattice elements was performed by the Mechanical Design Engineering Group of the Los Alamos Accelerator Operations and Technology Division. In order to determine effect of misalignment on beam parameters in LANSCE linac, the start-to-end simulations of LANSCE accelerator were performed using Beampath and CST codes including measured displacements of quadrupoles and accelerating tanks. Simulations were done for both H⁺ and H⁻ beams with various beam flavors. Effect of misalignments was compared with those due to beam space charge and distortion of RF field along the channel. Paper presents results of simulation and comparison with experimental data of beam emittance growth along the machine.
	Poster TUPA48 [1.547 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA48
About •	Received ※ 23 July 2022 — Revised ※ 28 July 2022 — Accepted ※ 04 August 2022 — Issue date ※ 14 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA57	Electromagnetic and Beam Dynamics Modeling of the LANSCE Coupled-Cavity Linac	472
	S.S. Kurennoy, Y.K. Batygin, D.V. Gorelov LANL, Los Alamos, New Mexico, USA
	The 800-MeV proton linac at LANSCE consists of a drift-tube linac, which brings the beam to 100 MeV, followed by a coupled-cavity linac (CCL) consisting of 44 modules. Each CCL module contains multiple tanks, and it is fed by a single 805-MHz klystron. CCL tanks are multi-cell blocks of identical re-entrant side-coupled cavities, which are followed by drifts with magnetic quadrupole doublets. Bridge couplers - special cavities displaced from the beam axis - electromagnetically couple CCL tanks over such drifts. We have developed 3D CST models of CCL tanks. Their electromagnetic analysis is performed using MicroWave Studio. Beam dynamics is modeled with Particle Studio for bunch trains with realistic beam distributions using the CST calculated RF fields and quadrupole magnetic fields to determine the output beam parameters. Beam dynamics results are crosschecked with other multi-particle codes.
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA57
About •	Received ※ 15 July 2022 — Revised ※ 01 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 19 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE1	Next-Generation Accelerator Facilities at Fermilab: Megawatt Upgrade of the NuMI Neutrino Beam
	R.M. Zwaska Fermilab, Batavia, Illinois, USA
	Fermilab is actively designing its next generation of proton accelerators (presently titled PIU - Proton Intensity Upgrade) to produce 2.4 MW of 120 GeV beam to the Long Baseline Neutrino Facility (LBNF), and deliver Megawatt scale beams to a suite of other particle physics experiments researching neutrinos, muons, dark matter, and other particle physics phenomena. These new accelerators will employ state-of-the-art superconducting RF, and rings that will accumulate, compress, and possibly accelerate beam to experiments with a rapid cycling synchrotron. The new accelerators at Fermilab will build off the under construction PIP-II Project - a unique CW superconducting H⁻ Linac. The approach will utilize much of the the existing accelerator complex (Recycler, Delivery Ring, and Main Injector) at higher intensity, and retire the original linac and Booster synchrotron. The PIU will use the major next experiments now under construction (LBNF and Mu2e). Novel beam formatting and delivery techniques may be developed for the next round of experiments. Additionally, R&D presently underway in beam dynamics, RF, and targetry may contribute to the capability of new accelerator facilities.
	Slides WEYE1 [31.401 MB]
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE2	Upgrade of the FRIB ReAccelerator	572
	A.C.C. Villari, B. Arend, G. Bollen, D.B. Crisp, K.D. Davidson, K. Fukushima, A.I. Henriques, K. Holland, S.H. Kim, A. Lapierre, Y. Liu, T. Maruta, D.G. Morris, S. Nash, P.N. Ostroumov, A.S. Plastun, J. Priller, S. Schwarz, B.M. Sherrill, M. Steiner, C. Sumithrarachchi, R. Walker, T. Zhang, Q. Zhao FRIB, East Lansing, Michigan, USA
	Funding: Work supported by the NSF under grant PHY15-65546 and DOE-SC under award number DE-SC0000661 The reaccelerator facility at FRIB was upgraded to provide new science opportunities. The upgrade included a new ion source to produce stable and long livied rare isotopes in a batch mode, a new room-temperature rebuncher, a new β = 0.085 quarter-wave-resonator cryomodule to increase the beam energy from 3 MeV/u to 6 MeV/u for ions with a charge-to-mass ratio of 1/4, and a new experimental vault with beamlines.
	Slides WEYE2 [4.220 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEYE2
About •	Received ※ 13 July 2022 — Revised ※ 01 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 10 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE3	Improvements to the Recycler/Main Injector to Deliver 850 kW+	578
	R. Ainsworth, P. Adamson, D. Capista, N. Chelidze, K.J. Hazelwood, I. Kourbanis, O. Mohsen, D.K. Morris, M.J. Murphy, M. Wren, M. Xiao Fermilab, Batavia, Illinois, USA C.E. Gonzalez-Ortiz MSU, East Lansing, Michigan, USA
	The Main Injector is used to deliver a 120 GeV high power proton beam for Neutrino experiments. The design power of 700 kW was reached in early 2017 but further improvements have seen a new sustained peak power of 893 kW. Two of the main improvements include the shortening of the Main Injector ramp length as well optimizing the slip-stacking procedure performed in the Recycler to reduce the amount of uncaptured beam making its way into the Main Injector. These improvements will be discussed in this paper as well future upgrades to reach higher beam powers.
	Slides WEYE3 [24.715 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEYE3
About •	Received ※ 02 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 18 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE4	Electron Cloud Simulations in the Fermilab Recycler	581
	A.P. Schreckenberger University of Illinois at Urbana-Champaign, Urbana, USA R. Ainsworth Fermilab, Batavia, Illinois, USA
	We present a simulation study to characterize the stability region of the Fermilab Recycler Ring in the context of secondary emission yield (SEY). Interactions between electrons and beam pipe material can produce electron clouds that jeopardize beam stability in certain focusing configurations. Such an instability was documented in the Recycler, and the work presented here reflects improvements to better understand that finding. We incorporated the Furman-Pivi Model into a PyECLOUD analysis, and we determined the instability threshold given various bunch lengths, beam intensities, SEY magnitudes, and model parameters.
	Slides WEYE4 [2.096 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEYE4
About •	Received ※ 01 August 2022 — Revised ※ 06 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 30 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE5	Model/Measurement Comparison of the Transverse Phase Space Distribution of an RFQ-Generated Bunch at the SNS BTF	584
	K.J. Ruisard, A.V. Aleksandrov, S.M. Cousineau, A.M. Hoover, A.P. Zhukov ORNL, Oak Ridge, Tennessee, USA
	Funding: This work is supported by US DOE, Office of Science, HEP. This manuscript is authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with US DOE. The research program at the SNS Beam Test Facility is focused on resolving observed model/measurement discrepancies that preclude accurate loss prediction in high-power linacs. The current program of study is focused on deploying direct 6D measurements to reconstruct a realistic model of the initial beam distribution at the RFQ output. This detailed characterization also provides an opportunity for benchmark of RFQ simulations. Here we compare PARMTEQ predictions against 5D-resolved (x, x’, y, y’, dE) phase space measurements of the BTF H⁻ bunch, focusing on the transverse distribution. This work is an extension of [1], which focused on the longitudinal phase space. [1] K. Ruisard et al., doi: 10.1103/PhysRevAccelBeams.23.124201. [2] A. Hoover et al., "Measurements of the Five-Dimensional Phase Space Distribution of a High-Intensity Ion Beam," these proceedings.
	Slides WEYE5 [2.646 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEYE5
About •	Received ※ 03 August 2022 — Revised ※ 11 August 2022 — Accepted ※ 13 August 2022 — Issue date ※ 04 October 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE6	Thermionic Sources for Electron Cooling at IOTA	588
	M.K. Bossard, Y.K. Kim University of Chicago, Chicago, Illinois, USA N. Banerjee, J.A. Brandt Enrico Fermi Institute, University of Chicago, Chicago, Illinois, USA B.L. Cathey, S. Nagaitsev, G. Stancari Fermilab, Batavia, Illinois, USA M.A. Krieg Saint Olaf College, Northfield, MN, USA
	We are planning a new electron cooling experiment at the Integrable Optics Test Accelerator (IOTA) at Fermilab for cooling ~2.5 MeV protons in the presence of intense space-charge. Here we present the simulations and design of a thermionic electron source for cooling at IOTA. We particularly discuss parameters of the thermionic source electrodes, as well as the simulation results. We also present a new electron source test-stand at the University of Chicago, which will be used to test the new thermionic electron source, as well as other electron sources. In addition, we discuss results from analyzing the test stand operations with a currently existing electron source. Furthermore, we present future steps for the test stand as well as production and commissioning of the thermionic source at IOTA.
	Slides WEYE6 [3.182 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEYE6
About •	Received ※ 02 August 2022 — Revised ※ 07 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 28 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD1	Instant Phase Setting in a Large Superconducting Linac	885
	A.S. Plastun, P.N. Ostroumov FRIB, East Lansing, Michigan, USA
	Funding: This work is supported by the U.S. Department of Energy Office of Science under Cooperative Agreement No. DE-SC0000661, the State of Michigan, and Michigan State University. The instant phase setting reduces the time needed to setup 328 radiofrequency cavities of the Facility for Rare Isotope Beams (FRIB) linac from 20 hours to 10 minutes. This technique uses a 1-D computer model of the linac to predict the cavities’ phases. The model has been accurately calibrated using the data of the 360-degree phase scans - a common procedure for phasing of linear accelerators. The model was validated by comparison with a conventional phase scan results. The predictions applied to the linac are then verified by multiple time-of-flight energy measurements and the response of the beam position/phase monitors (BPMs) to an intentional energy and phase mismatch. The presented approach not just reduces the time and the effort required to tune the FRIB accelerator for new experiments every couple of weeks, but it also provides an easy recovery from cavity failures. It is beneficial for user facilities requiring high beam availability, as well as for radioactive ion beam accelerators, where quick time-of-flight energy measurement via the BPMs is not possible due to the low intensities of these beams.
	Slides THZD1 [2.610 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD1
About •	Received ※ 07 August 2022 — Revised ※ 09 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 21 August 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD2	Advances in the ATLAS Accelerator
	M.P. Kelly, C. Dickerson, B.M. Guilfoyle, M.R. Hendricks, M. Kedzie, T.B. Petersen, T. Reid ANL, Lemont, Illinois, USA
	Funding: DOE-NP The ATLAS Superconducting Linac at Argonne National Laboratory is a leading facility for nuclear reaction and structure studies, providing ion beams over the full mass range to a community of users from the US and abroad. The technology of ATLAS has been continuously upgraded since commissioning in 1978 and has remained at the forefront of superconducting linac development, especially for low-beta Linacs, for more than four decades. We present an overview of the present state ATLAS superconducting technology, the latest approaches for superconducting cavity cryomodules commissioned within the last 10 years and the outlook and potential impact of transformative new technologies to low-beta ion accelerators.
	Slides THZD2 [14.708 MB]
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD3	Design of 3-GeV High-Gradient Booster for Upgraded Proton Radiography at LANSCE	891
	Y.K. Batygin, S.S. Kurennoy LANL, Los Alamos, New Mexico, USA
	Funding: Work supported by US DOE under contract 89233218CNA000001 Increasing the proton beam energy from the present 800 MeV to 3 GeV will improve the resolution of the Proton Radiography Facility at the Los Alamos Neutron Science Center (LANSCE) by a factor of 10. It will bridge the gap between the existing facilities, which covers large length scales for thick objects, and future high-brightness light sources, which can provide the finest resolution. Proton radiography requires a sequence of short beam pulses (~20 x 80 ns) separated by intervals of variable duration, from about 300 ns to 1 to 2 μs. To achieve the required parameters, the high gradient 3-GeV booster is proposed. The booster consists of 1.4 GHz buncher, two accelerators based on 2.8 GHz and 5.6 GHz high-gradient accelerating structures and 1.4 GHz debuncher. Utilization of buncher-accelerator-debuncher scheme allows us to combine high-gradient acceleration with significant reduction of beam momentum spread. Paper discusses details of linac design and expected beam parameters.
	Slides THZD3 [2.348 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD3
About •	Received ※ 28 July 2022 — Revised ※ 06 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 04 October 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD4	Accelerating Structures for High-Gradient Proton Radiography Booster at LANSCE	894
	S.S. Kurennoy, Y.K. Batygin, E.R. Olivas LANL, Los Alamos, New Mexico, USA
	Increasing energy of proton beam at LANSCE from 800 MeV to 3 GeV improves radiography resolution ~10 times. We proposed accomplishing such an energy boost with a compact cost-effective linac based on normal conducting high-gradient (HG) RF accelerating structures. Such an unusual proton linac is feasible for proton radiography (pRad), which operates with short RF pulses. For a compact pRad booster at LANSCE, we have developed a multi-stage design: a short L-band section to capture and compress the 800-MeV proton beam followed by the main HG linac based on S- and C-band cavities, and finally, by an L-band de-buncher [1]. Here we present details of development, including EM and thermal-stress analysis, of proton HG structures with distributed RF coupling for the pRad booster. A simple two-cell structure with distributed coupling is being fabricated and will be tested at the LANL C-band RF Test Stand. [1] S.S. Kurennoy, Y.K. Batygin. IPAC21, MOPAB210.
	Slides THZD4 [1.591 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD4
About •	Received ※ 01 August 2022 — Revised ※ 10 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 26 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD5	Modelling H⁻ Injection and Painting in Vertical and Horizontal FFAs Using OPAL
	C.T. Rogers STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom A. Adelmann PSI, Villigen PSI, Switzerland
	H⁻ phase space painting using charge-exchange has been used in synchrotrons to inject and accumulate high intensity bunches of protons, but has never been used in Fixed Field Accelerators (FFAs). In H⁻ charge-exchange injection, H⁻ ions pass through a thin foil where the electrons are stripped from the ion leaving a proton. In combination with an appropriate dipole, well-separated H⁻ ion and proton beams converge at the foil in this non-Liouvillean process. This can be combined with painting of the phase space, where the position of the injected beam is manipulated with respect to the circulating protons in order to inject beams having a specific profile in phase-space. In this paper the simulation of such injection is studied, performed using the latest improvements in the OPAL code. Injection into a small test ring that is under development as part of the ISIS upgrade program is considered.
	Slides THZD5 [1.093 MB]
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD6	An 8 GeV Linac as the Booster Replacement in the Fermilab Power Upgrade	897
	D.V. Neuffer, S.A. Belomestnykh, M. Checchin, D.E. Johnson, S. Posen, E. Pozdeyev, V.S. Pronskikh, A. Saini, N. Solyak, V.P. Yakovlev Fermilab, Batavia, Illinois, USA
	Funding: Work supported by the Fermi National Accelerator Laboratory, managed and operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy. Increasing the Main Injector (MI) beam power above ~1.2 MW requires replacement of the 8-GeV Booster by a higher intensity alternative. In the Project X era, rapid-cycling synchrotron (RCS) and linac solutions were considered for this purpose. In this paper, we consider the linac version that produces 8 GeV H⁻ beam for injection into the Recycler Ring (RR) or Main Injector (MI). The linac takes ~1-GeV beam from the PIP-II Linac and accelerates it to ~2 GeV in a 650-MHz SRF linac, followed by a 8-GeV pulsed linac using 1300 MHz cryomodules. The linac components incorporate recent improvements in SRF technology. Research needed to implement the high power SRF Linac is described.
	Slides THZD6 [4.078 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD6
About •	Received ※ 03 August 2022 — Revised ※ 11 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 04 October 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

The Effect of the Main Injector Ramp on the Recycler

90

N. Chelidze, R. Ainsworth, K.J. Hazelwood
Fermilab, Batavia, Illinois, USA

The Recycler and Main Injector are part of the Fermilab Accelerator complex used to deliver a high power proton beam. Both machines share the same enclosure with the Recycler mounted 6 ft above the Main Injector. The Main Injector accelerates beam from 8 GeV to 120 GeV. While the majority of the Recycler has mu metal shielding, the effect of the Main Injector ramp is still significant and can affect both the tunes and the orbit. In this paper, we detail the size of these effects.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-MOPA19

About •

Received ※ 02 August 2022 — Accepted ※ 04 August 2022 — Issue date ※ 23 August 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA05

An H⁻ Injector for the ESS Storage Ring

357

V.G. Dudnikov, M.A. Cummings, M. Popovic
Muons, Inc, Illinois, USA

H⁻ charge exchange (stripping) injection into the European Spallation neutron Source (ESS) Storage Ring requires a 90 mA H⁻ ion source that delivers 2.9 ms pulses at 14 Hz repetition rate (duty factor ~4%) that can be extended to 28 Hz (df 8%). This can be achieved with a magnetron surface plasma H⁻ source (SPS) with active cathode and anode cooling. The Brookhaven National Laboratory (BNL) magnetron SPS can produce an H⁻ beam current of 100 mA with about 2 kW discharge power and can operate up to 0.7 % duty factor (average power 14 W) without active cooling. We describe how active cathode and anode cooling can be applied to the BNL source to increase the average discharge power up to 140 W (df 8%) to satisfy the needs of the ESS. We also describe the use of a short electrostatic LEBT as is used at the Oak Ridge National Laboratory Spallation Neutron Source to improve the beam delivery to the RFQ.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA05

About •

Received ※ 02 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 04 September 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA48

Effect of Lattice Misalignments on Beam Dynamics in LANSCE Linear Accelerator

455

Y.K. Batygin, S.S. Kurennoy
LANL, Los Alamos, New Mexico, USA

Funding: Work supported by US DOE under contract 89233218CNA000001
Accelerator channel misalignments can significantly affect beam parameters in long linear accelerators. Measurements of misalignments of the LANSCE linac lattice elements was performed by the Mechanical Design Engineering Group of the Los Alamos Accelerator Operations and Technology Division. In order to determine effect of misalignment on beam parameters in LANSCE linac, the start-to-end simulations of LANSCE accelerator were performed using Beampath and CST codes including measured displacements of quadrupoles and accelerating tanks. Simulations were done for both H⁺ and H⁻ beams with various beam flavors. Effect of misalignments was compared with those due to beam space charge and distortion of RF field along the channel. Paper presents results of simulation and comparison with experimental data of beam emittance growth along the machine.

Poster TUPA48 [1.547 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA48

About •

Received ※ 23 July 2022 — Revised ※ 28 July 2022 — Accepted ※ 04 August 2022 — Issue date ※ 14 August 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPA57

Electromagnetic and Beam Dynamics Modeling of the LANSCE Coupled-Cavity Linac

472

S.S. Kurennoy, Y.K. Batygin, D.V. Gorelov
LANL, Los Alamos, New Mexico, USA

The 800-MeV proton linac at LANSCE consists of a drift-tube linac, which brings the beam to 100 MeV, followed by a coupled-cavity linac (CCL) consisting of 44 modules. Each CCL module contains multiple tanks, and it is fed by a single 805-MHz klystron. CCL tanks are multi-cell blocks of identical re-entrant side-coupled cavities, which are followed by drifts with magnetic quadrupole doublets. Bridge couplers - special cavities displaced from the beam axis - electromagnetically couple CCL tanks over such drifts. We have developed 3D CST models of CCL tanks. Their electromagnetic analysis is performed using MicroWave Studio. Beam dynamics is modeled with Particle Studio for bunch trains with realistic beam distributions using the CST calculated RF fields and quadrupole magnetic fields to determine the output beam parameters. Beam dynamics results are crosschecked with other multi-particle codes.

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-TUPA57

About •

Received ※ 15 July 2022 — Revised ※ 01 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 19 August 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE1

Next-Generation Accelerator Facilities at Fermilab: Megawatt Upgrade of the NuMI Neutrino Beam

R.M. Zwaska
Fermilab, Batavia, Illinois, USA

Fermilab is actively designing its next generation of proton accelerators (presently titled PIU - Proton Intensity Upgrade) to produce 2.4 MW of 120 GeV beam to the Long Baseline Neutrino Facility (LBNF), and deliver Megawatt scale beams to a suite of other particle physics experiments researching neutrinos, muons, dark matter, and other particle physics phenomena. These new accelerators will employ state-of-the-art superconducting RF, and rings that will accumulate, compress, and possibly accelerate beam to experiments with a rapid cycling synchrotron. The new accelerators at Fermilab will build off the under construction PIP-II Project - a unique CW superconducting H⁻ Linac. The approach will utilize much of the the existing accelerator complex (Recycler, Delivery Ring, and Main Injector) at higher intensity, and retire the original linac and Booster synchrotron. The PIU will use the major next experiments now under construction (LBNF and Mu2e). Novel beam formatting and delivery techniques may be developed for the next round of experiments. Additionally, R&D presently underway in beam dynamics, RF, and targetry may contribute to the capability of new accelerator facilities.

Slides WEYE1 [31.401 MB]

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE2

Upgrade of the FRIB ReAccelerator

572

A.C.C. Villari, B. Arend, G. Bollen, D.B. Crisp, K.D. Davidson, K. Fukushima, A.I. Henriques, K. Holland, S.H. Kim, A. Lapierre, Y. Liu, T. Maruta, D.G. Morris, S. Nash, P.N. Ostroumov, A.S. Plastun, J. Priller, S. Schwarz, B.M. Sherrill, M. Steiner, C. Sumithrarachchi, R. Walker, T. Zhang, Q. Zhao
FRIB, East Lansing, Michigan, USA

Funding: Work supported by the NSF under grant PHY15-65546 and DOE-SC under award number DE-SC0000661
The reaccelerator facility at FRIB was upgraded to provide new science opportunities. The upgrade included a new ion source to produce stable and long livied rare isotopes in a batch mode, a new room-temperature rebuncher, a new β = 0.085 quarter-wave-resonator cryomodule to increase the beam energy from 3 MeV/u to 6 MeV/u for ions with a charge-to-mass ratio of 1/4, and a new experimental vault with beamlines.

Slides WEYE2 [4.220 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEYE2

About •

Received ※ 13 July 2022 — Revised ※ 01 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 10 August 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE3

Improvements to the Recycler/Main Injector to Deliver 850 kW+

578

R. Ainsworth, P. Adamson, D. Capista, N. Chelidze, K.J. Hazelwood, I. Kourbanis, O. Mohsen, D.K. Morris, M.J. Murphy, M. Wren, M. Xiao
Fermilab, Batavia, Illinois, USA
C.E. Gonzalez-Ortiz
MSU, East Lansing, Michigan, USA

The Main Injector is used to deliver a 120 GeV high power proton beam for Neutrino experiments. The design power of 700 kW was reached in early 2017 but further improvements have seen a new sustained peak power of 893 kW. Two of the main improvements include the shortening of the Main Injector ramp length as well optimizing the slip-stacking procedure performed in the Recycler to reduce the amount of uncaptured beam making its way into the Main Injector. These improvements will be discussed in this paper as well future upgrades to reach higher beam powers.

Slides WEYE3 [24.715 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEYE3

About •

Received ※ 02 August 2022 — Revised ※ 08 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 18 August 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE4

Electron Cloud Simulations in the Fermilab Recycler

581

A.P. Schreckenberger
University of Illinois at Urbana-Champaign, Urbana, USA
R. Ainsworth
Fermilab, Batavia, Illinois, USA

We present a simulation study to characterize the stability region of the Fermilab Recycler Ring in the context of secondary emission yield (SEY). Interactions between electrons and beam pipe material can produce electron clouds that jeopardize beam stability in certain focusing configurations. Such an instability was documented in the Recycler, and the work presented here reflects improvements to better understand that finding. We incorporated the Furman-Pivi Model into a PyECLOUD analysis, and we determined the instability threshold given various bunch lengths, beam intensities, SEY magnitudes, and model parameters.

Slides WEYE4 [2.096 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEYE4

About •

Received ※ 01 August 2022 — Revised ※ 06 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 30 September 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE5

Model/Measurement Comparison of the Transverse Phase Space Distribution of an RFQ-Generated Bunch at the SNS BTF

584

K.J. Ruisard, A.V. Aleksandrov, S.M. Cousineau, A.M. Hoover, A.P. Zhukov
ORNL, Oak Ridge, Tennessee, USA

Funding: This work is supported by US DOE, Office of Science, HEP. This manuscript is authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with US DOE.
The research program at the SNS Beam Test Facility is focused on resolving observed model/measurement discrepancies that preclude accurate loss prediction in high-power linacs. The current program of study is focused on deploying direct 6D measurements to reconstruct a realistic model of the initial beam distribution at the RFQ output. This detailed characterization also provides an opportunity for benchmark of RFQ simulations. Here we compare PARMTEQ predictions against 5D-resolved (x, x’, y, y’, dE) phase space measurements of the BTF H⁻ bunch, focusing on the transverse distribution. This work is an extension of [1], which focused on the longitudinal phase space.
[1] K. Ruisard et al., doi: 10.1103/PhysRevAccelBeams.23.124201.
[2] A. Hoover et al., "Measurements of the Five-Dimensional Phase Space Distribution of a High-Intensity Ion Beam," these proceedings.

Slides WEYE5 [2.646 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEYE5

About •

Received ※ 03 August 2022 — Revised ※ 11 August 2022 — Accepted ※ 13 August 2022 — Issue date ※ 04 October 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEYE6

Thermionic Sources for Electron Cooling at IOTA

588

M.K. Bossard, Y.K. Kim
University of Chicago, Chicago, Illinois, USA
N. Banerjee, J.A. Brandt
Enrico Fermi Institute, University of Chicago, Chicago, Illinois, USA
B.L. Cathey, S. Nagaitsev, G. Stancari
Fermilab, Batavia, Illinois, USA
M.A. Krieg
Saint Olaf College, Northfield, MN, USA

We are planning a new electron cooling experiment at the Integrable Optics Test Accelerator (IOTA) at Fermilab for cooling ~2.5 MeV protons in the presence of intense space-charge. Here we present the simulations and design of a thermionic electron source for cooling at IOTA. We particularly discuss parameters of the thermionic source electrodes, as well as the simulation results. We also present a new electron source test-stand at the University of Chicago, which will be used to test the new thermionic electron source, as well as other electron sources. In addition, we discuss results from analyzing the test stand operations with a currently existing electron source. Furthermore, we present future steps for the test stand as well as production and commissioning of the thermionic source at IOTA.

Slides WEYE6 [3.182 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-WEYE6

About •

Received ※ 02 August 2022 — Revised ※ 07 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 28 August 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD1

Instant Phase Setting in a Large Superconducting Linac

885

A.S. Plastun, P.N. Ostroumov
FRIB, East Lansing, Michigan, USA

Funding: This work is supported by the U.S. Department of Energy Office of Science under Cooperative Agreement No. DE-SC0000661, the State of Michigan, and Michigan State University.
The instant phase setting reduces the time needed to setup 328 radiofrequency cavities of the Facility for Rare Isotope Beams (FRIB) linac from 20 hours to 10 minutes. This technique uses a 1-D computer model of the linac to predict the cavities’ phases. The model has been accurately calibrated using the data of the 360-degree phase scans - a common procedure for phasing of linear accelerators. The model was validated by comparison with a conventional phase scan results. The predictions applied to the linac are then verified by multiple time-of-flight energy measurements and the response of the beam position/phase monitors (BPMs) to an intentional energy and phase mismatch. The presented approach not just reduces the time and the effort required to tune the FRIB accelerator for new experiments every couple of weeks, but it also provides an easy recovery from cavity failures. It is beneficial for user facilities requiring high beam availability, as well as for radioactive ion beam accelerators, where quick time-of-flight energy measurement via the BPMs is not possible due to the low intensities of these beams.

Slides THZD1 [2.610 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD1

About •

Received ※ 07 August 2022 — Revised ※ 09 August 2022 — Accepted ※ 10 August 2022 — Issue date ※ 21 August 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD2

Advances in the ATLAS Accelerator

M.P. Kelly, C. Dickerson, B.M. Guilfoyle, M.R. Hendricks, M. Kedzie, T.B. Petersen, T. Reid
ANL, Lemont, Illinois, USA

Funding: DOE-NP
The ATLAS Superconducting Linac at Argonne National Laboratory is a leading facility for nuclear reaction and structure studies, providing ion beams over the full mass range to a community of users from the US and abroad. The technology of ATLAS has been continuously upgraded since commissioning in 1978 and has remained at the forefront of superconducting linac development, especially for low-beta Linacs, for more than four decades. We present an overview of the present state ATLAS superconducting technology, the latest approaches for superconducting cavity cryomodules commissioned within the last 10 years and the outlook and potential impact of transformative new technologies to low-beta ion accelerators.

Slides THZD2 [14.708 MB]

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD3

Design of 3-GeV High-Gradient Booster for Upgraded Proton Radiography at LANSCE

891

Y.K. Batygin, S.S. Kurennoy
LANL, Los Alamos, New Mexico, USA

Funding: Work supported by US DOE under contract 89233218CNA000001
Increasing the proton beam energy from the present 800 MeV to 3 GeV will improve the resolution of the Proton Radiography Facility at the Los Alamos Neutron Science Center (LANSCE) by a factor of 10. It will bridge the gap between the existing facilities, which covers large length scales for thick objects, and future high-brightness light sources, which can provide the finest resolution. Proton radiography requires a sequence of short beam pulses (~20 x 80 ns) separated by intervals of variable duration, from about 300 ns to 1 to 2 μs. To achieve the required parameters, the high gradient 3-GeV booster is proposed. The booster consists of 1.4 GHz buncher, two accelerators based on 2.8 GHz and 5.6 GHz high-gradient accelerating structures and 1.4 GHz debuncher. Utilization of buncher-accelerator-debuncher scheme allows us to combine high-gradient acceleration with significant reduction of beam momentum spread. Paper discusses details of linac design and expected beam parameters.

Slides THZD3 [2.348 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD3

About •

Received ※ 28 July 2022 — Revised ※ 06 August 2022 — Accepted ※ 08 August 2022 — Issue date ※ 04 October 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD4

Accelerating Structures for High-Gradient Proton Radiography Booster at LANSCE

894

S.S. Kurennoy, Y.K. Batygin, E.R. Olivas
LANL, Los Alamos, New Mexico, USA

Increasing energy of proton beam at LANSCE from 800 MeV to 3 GeV improves radiography resolution ~10 times. We proposed accomplishing such an energy boost with a compact cost-effective linac based on normal conducting high-gradient (HG) RF accelerating structures. Such an unusual proton linac is feasible for proton radiography (pRad), which operates with short RF pulses. For a compact pRad booster at LANSCE, we have developed a multi-stage design: a short L-band section to capture and compress the 800-MeV proton beam followed by the main HG linac based on S- and C-band cavities, and finally, by an L-band de-buncher [1]. Here we present details of development, including EM and thermal-stress analysis, of proton HG structures with distributed RF coupling for the pRad booster. A simple two-cell structure with distributed coupling is being fabricated and will be tested at the LANL C-band RF Test Stand.
[1] S.S. Kurennoy, Y.K. Batygin. IPAC21, MOPAB210.

Slides THZD4 [1.591 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD4

About •

Received ※ 01 August 2022 — Revised ※ 10 August 2022 — Accepted ※ 11 August 2022 — Issue date ※ 26 September 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD5

Modelling H⁻ Injection and Painting in Vertical and Horizontal FFAs Using OPAL

C.T. Rogers
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
A. Adelmann
PSI, Villigen PSI, Switzerland

H⁻ phase space painting using charge-exchange has been used in synchrotrons to inject and accumulate high intensity bunches of protons, but has never been used in Fixed Field Accelerators (FFAs). In H⁻ charge-exchange injection, H⁻ ions pass through a thin foil where the electrons are stripped from the ion leaving a proton. In combination with an appropriate dipole, well-separated H⁻ ion and proton beams converge at the foil in this non-Liouvillean process. This can be combined with painting of the phase space, where the position of the injected beam is manipulated with respect to the circulating protons in order to inject beams having a specific profile in phase-space. In this paper the simulation of such injection is studied, performed using the latest improvements in the OPAL code. Injection into a small test ring that is under development as part of the ISIS upgrade program is considered.

Slides THZD5 [1.093 MB]

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THZD6

An 8 GeV Linac as the Booster Replacement in the Fermilab Power Upgrade

897

D.V. Neuffer, S.A. Belomestnykh, M. Checchin, D.E. Johnson, S. Posen, E. Pozdeyev, V.S. Pronskikh, A. Saini, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, Illinois, USA

Funding: Work supported by the Fermi National Accelerator Laboratory, managed and operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
Increasing the Main Injector (MI) beam power above ~1.2 MW requires replacement of the 8-GeV Booster by a higher intensity alternative. In the Project X era, rapid-cycling synchrotron (RCS) and linac solutions were considered for this purpose. In this paper, we consider the linac version that produces 8 GeV H⁻ beam for injection into the Recycler Ring (RR) or Main Injector (MI). The linac takes ~1-GeV beam from the PIP-II Linac and accelerates it to ~2 GeV in a 650-MHz SRF linac, followed by a 8-GeV pulsed linac using 1300 MHz cryomodules. The linac components incorporate recent improvements in SRF technology. Research needed to implement the high power SRF Linac is described.

Slides THZD6 [4.078 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-NAPAC2022-THZD6

About •

Received ※ 03 August 2022 — Revised ※ 11 August 2022 — Accepted ※ 12 August 2022 — Issue date ※ 04 October 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)