This paper presents the application of SciBmad tracking, a component of the SciBmad software ecosystem for differentiable accelerator physics simulations in Julia. The study demonstrates the use of phase space tomography to reconstruct the phase space distribution of a particle beam given the two-dimensional projections of its phase space distribution. Using the SciBmad tracking interface, the...
As part of the LANSCE Accelerator Modernization Project (LAMP), the two existing 750-keV Cockcroft Waltons are planned to be replaced by a single radio-frequency quadrupole (RFQ). The new LAMP front-end needs to deliver beams with similar timing patterns to what is currently delivered to the multiple target stations. To accomplish this, the 3-MeV Medium Energy Beam Transport (MEBT) is designed...
A major obstacle to collaboration on accelerator projects has been the sharing of lattice description files among modeling codes. To address this problem, a standardized lattice description called the Particle Accelerator Lattice Standard (PALS) is being developed. PALS development is a community-wide international effort involving accelerator physicists from multiple institutions. Along with...
As the scale of the EIC project continues to grow, beam-beam simulations incorporating increasingly realistic models are becoming essential. Consequently, a high-performance and extensible simulation code is indispensable. In this contribution, we report on our progress in developing a GPU-parallelized weak-strong beam-beam tracking code in the Julia programming language.
During the 2024 Au+Au 100 GeV physics run, the sPHENIX MVTX detector experienced background issues originating from the Yellow beam, leading to frequent auto-recoveries during streaming mode operation. One hypothesis attributes the background to the loss of off-momentum particles. An evaluation of the momentum apertures in both RHIC rings revealed that the Yellow ring had a worse momentum...
We discuss a bunch lengthening scheme based on the combination of Higher Harmonic Cavities (HHCs) of different order, aimed to provide a higher bunch lengthening factor then HHC systems of the same order. The stability and performance of the HHCs scheme is studied numerically with parameters of the NSLS-II upgrade.
We present a study of halo formation mechanisms in the high-power PIP-II SRF linac, combining analytical modeling with self-consistent 3D Particle-In-Cell (PIC) simulations. Focusing on the low-energy front-end and transitions between SRF cavity families, we use PIC simulations with realistic 3D field maps to analyze the evolution of the beam distribution. Our results demonstrate that...
Cooling of hadrons in Electron Ion Collider (EIC) at the injection energy is critical to achieving EIC design parameters. A 13 MeV electron cooler fit for the task is presently under design.
This cooler will use RF-accelerated electron bunches and will provide strong cooling of the hadrons having energy of 24 GeV/nucleon. The paper describes optimization of the cooling performance, taking...
When the closed-orbit spin tune is ramped linearly through an isolated spin-orbit resonance, the asymptotic polarization loss is well-approximated by the Froissart-Stora formula. However, it is often observed in accelerator simulations that the crossing speed, defined as the slope of the amplitude-dependent spin tune with respect to the machine azimuth, changes at the moment of resonance...
Integrable nonlinear lattices that can be realized in practical accelerators are of great interest, as they offer the potential to support high-intensity beams via Landau damping of collective instabilities. One such system, based on an elliptic potential, has been extensively studied at the IOTA storage ring at Fermilab. The analysis of strongly nonlinear dynamics with multi-particle bunches...
A new method is formulated for calculating the invariant spin field (ISF) at a phase space point by leveraging the property that spins which are distributed along the ISF achieve maximum time-averaged polarization. To quantify this, we construct the time-average of spin rotation matrices beginning at a certain phase space point. It is recognized that the ISF vector at that point achieves the...
Beam halo refers to the low-density distribution of particles extending beyond the beam core, and its generation and mitigation are important topics in particle accelerator design. Effective mitigation of beam halo is essential for the cooler design based on Energy Recovery Linac (ERL), which must deliver an electron beam with average beam current of 100 mA and a charge 1 nC per bunch. In the...
Passive wakefield devices such as corrugated structures have demontrated great potential for longitudinal phase space control and diagnostics in FEL. In this paper, we will discuss the application of corrugated structures in beam tilt characterization. We show that a tilted beam experience asymmetric kicks when passing through corrugated metal jaws and the asymmetry of streaked profiles are...
Solenoid focusing is commonly used in accelerators for electron beam containment and to compensate for space charge-induced emittance growth at low beam energies. However, misalignment between the solenoid field and the beam trajectory can result in degraded emittance compensation due to dispersive effects and geometric aberrations in the magnetic solenoid. This paper presents a technique for...
This work presents a generalized theoretical framework for calculating beam–beam fields induced by a Gaussian beam with full six-dimensional coupling. In addition, we develop computational techniques for evaluating these fields. A case study based on the Electron-Ion Collider (EIC) electron storage ring is used to demonstrate the practical application of the framework. The potential...
Achieving the design luminosity of $10^{34}\ \mathrm{cm}^{−2}\mathrm{s}^{−1}$ in the Electron-Ion Collider (EIC) requires a deep understanding of beam-beam interaction limits in a weak-strong collision regime with flat hadron beams. This contribution presents recent studies of synchro-betatron resonances --- particularly the coupling resonance 2nux-2nuy+p*nuz=0 --- that can induce emittance...
BeamNetUS is a network of facilities united in a common mission to advance accelerator research and applications of accelerator technology through improving awareness and access to these unique facilities. For its pilot campaign, the network includes facilities at Argonne National Laboratory, Brookhaven National Laboratory, Fermi National Accelerator Laboratory, Lawrence Berkeley National...
Accurate studies of particle behavior in accelerator chambers require precise magnetic field maps with regard to the iron geometry. We generated a realistic magnetic-field map for the 76-inch cyclotron at Crocker Nuclear Lab using COMSOL Multiphysics, then imported it into the OPAL (Object-Oriented Parallel Accelerator Library) software to model particle trajectories. It accurately simulates...
GdfidL has been used to calculate the resistive wall heating in the vacuum components of the Electron-Ion Collider (EIC). In this paper, we present the simulation results for the beam-induced resistive wake potentials in various vacuum components of the EIC, including the beam screen and the hadron polarimeter in the hadron storage ring (HSR). The resistive wall losses are calculated from the...
The continuing development of radio-frequency (RF) amplifier technology has paved the way for RF electron accelerators in which each cavity is independently powered, allowing the amplitude and phases to be individually tunable. In this work we study the potential benefits provided by this flexibility in maximizing the capture efficiency in a ≈2 MeV compact accelerator suitable for a wide...
A prototype colliding beam accelerator has been fabricated for the study of a fusion-based propulsion concept for interplanetary exploration. The purpose of this prototype is to demonstrate collider luminosities commensurate with the requirements of this application. Direct emission of fusion daughters generates the exhaust velocities required for spacecraft speeds in excess of 1% of the...
Two types of beam abort mechanisms, namely, the External Abort System and the Internal Abort System for the Electron Ion Collider (EIC) Electron Storage Ring (ESR) are devised, designed and compared. Both mechanisms will be located in the Interaction region 2 (IR2). The External Abort System utilizes the ISABELLE Spectrometer tunnel to facilitate an extraction beamline and a beam dump, and the...
We present a method to construct high-order polynomial approximate invariants (AI) for non-integrable Hamiltonian dynamical systems, and apply it to a modern ring-based particle accelerator. Taking advantage of a special property of one-turn transformation maps in the form of a square matrix, AIs can be constructed order-by-order iteratively. Evaluating AI with simulation data, we observe that...
This paper shows a CST simulation of a 6 cell Superconducting (SC) cavity with potential application at LANSCE. Previous studies explored the Superconducting LINAC (SCL) option as a potential upgrade to the LANSCE Coupled Cavity LINAC (CCL). This SC option has the potential to improve beam availability to the LANSCE facility users by allowing the RF system to partially migrate to a modern RF...
The electron injection system of the U.S. Electron-Ion Collider (EIC) is located outside of the RHIC tunnel. Electrons beams accelerated by the Rapid Cycling Synchrotron (RCS) must be transported to the Electron Storage Ring (ESR), which resides within the RHIC tunnel. To accomplish this, a dedicated beam transport line, referred to as RTE (RCS-to-ESR) line is being designed. The proposed...
The microwave instability is typically driven by perturbations whose characteristic wavelength is much shorter than the bunch. In this case, Boussard argued that the microwave instability threshold can be found using the predictions of an infinite (coasting) beam, with the average current replaced by the peak current*. We revisit this problem, and theoretically show that if the variation of...
We describe the design of a symmetrical skew-quadrupole triplet and associated four-quadrupole matching section for a flat-to-vortex beam transformation in a low-energy, high current electron experiment at the University of Maryland. We review the basic principles involved, from the Courant-Snyder parameters, beam (sigma) matrix, conservation of canonical angular momentum and emittances, to...
For Jefferson Lab’s 22¿GeV upgrade, two new permanent-magnet Fixed-Field Alternating Gradient (FFA) arcs will be integrated to serve the accelerator’s six highest-energy recirculation passes. Connecting these FFA arcs to the existing linear accelerator (linac) requires a carefully engineered transition section. The current design has two parts where the first part adiabatically matches the...
Monte Carlo simulations are a powerful tool for modeling photoemission from photocathodes, enabling the prediction of key parameters such as quantum efficiency, mean transverse energy, electron spin polarization, and photocathode response time. However, these simulations require material band structure parameters, which are not always available from experiments. This work aims to establish a...
The Ring Electron Cooler is one option to provide cooling to the Electron Ion Collider’s 275 GeV proton bunches. Using traditional electron cooling this racetrack shaped storage ring uses one straight section to cool the protons and the other one to enhance the radiation damping of the electrons using 2.4 T wigglers. These sections comprise the majority of the ring and are connected by short...
As part of the Proton Improvement Plan II (PIP-II), Fermilab aims to increase beam intensity delivered to neutrino experiments. In this context, higher intensity injection into the Recycler Ring enhances space charge effects, pushing operations closer to third-order resonances. These resonances reduce the Dynamic Aperture (DA), leading to increased beam loss. This study presents simulations of...
Optimizing accelerator lattices requires evaluating phase space densities through extended or repeated particle-in-cell simulations. These are computationally expensive due to the need to solve the equations of motion for large numbers of charged particles in prescribed and self-consistent fields. We introduce a method that significantly reduces the computational burden by constructing...
Instabilities in room temperature accelerator RF cavities due to interaction between electromagnetic RF field and mechanical vibrational modes of the cavity has been observed in 1960s [1,2]. In superconducting RF (SRF) cavities these types of instabilities may be even stronger because of larger beam loading factor (Q_L), large cavity field, and stronger effects of cavity de-tuning due to...
We present an analytical and numerical study of the electromagnetic space-charge fields generated by a relativistic charged particle beam propagating inside a cylindrical conducting cavity with a small aperture at one end. The system models a practical RF photoinjector geometry where the beam originates from a flat cathode and accelerates longitudinally through the cavity. By employing a...
The Electron-Ion Collider (EIC), to be constructed at Brookhaven National Laboratory, will collide polarized high-energy electron beams with polarized proton and ion beams, achieving luminosities of up to 1 × 10^34 cm^−2 s^−1 in the center-of-mass energy range of 20-140 GeV. The EIC consists of two storage rings: the Hadron Storage Ring (HSR) and the Electron Storage Ring (ESR). Given the...
Ultrafast electron diffraction (UED) probes structural dynamics on femtosecond timescales and angstrom spatial scales. Artificial crystals are a novel experimental target for UED beams. Typically composed of lattice-mismatched atomic layers, the repeating atomic patterns in artificial crystals can have periods several nanometers in length, which produces intricate satellite features in the...
Reliable and fast wakefield calculations are important for beam dynamics and THz generation in accelerators. We compare approaches and limitations with different available simulation tools and compare results. As an example, we analyze a cylindrical corrugated waveguide with narrower and wider radii of 5 and 6 mm, and aperture width and periodicity of 1 and 2 mm using ABCI by KEK and ANSYS...
Idealized models predict beam moments and envelopes, but not the detailed beam structure within those envelopes. We explore in experiment and simulation the interplay of space charge and angular momentum with realistic beam distributions in a low-energy transport system. Our realistic phase space distributions derive from direct experimental measurements near the beam source. The platform for...
The representation of beam transport through magnetic dipole fringe fields using effective "thin" maps has a long history. More recent work has extended the second-order Taylor model of Brown by providing Lie generators for symplectic maps that capture effects at higher order, expressed in terms of field integrals. These maps can be cumbersome to evaluate in an explicit symplectic form...
The Spallation Neutron Source uses charge exchange injection of 1.3 GeV, H- ions to accumulate roughly 2x10E protons per pulse in the accumulator ring. This is achieved using a flexible painting system capable of controlling all four transverse coordinates of injected beam over the 1ms injection cycle. Recently we demonstrated injection of an ~800 MeV beam into a single non-planar mode in the...
Symplecticity of transfer maps is important for reliable evaluation of space-charge dominated beams in accelerators. Unfortunately, most simulation codes that include collective effects, such as space charge, do not use canonical phase-space variables and therefore are not symplectic in the presence of electromagnetic fields. In this paper, we present a numerical method to extract symplectic...
The emission of transition radiation as a relativistic beam passes through a metallic foil usually has negligible impact on the high-energy beam itself. However, if the beam has very high current, such as those from the FACET-II facility, the near-field of the transition radiation can provide a strong focusing force on the beam which can be enhanced by passing through multiple closely spaced...
A failure of the RHIC superconducting circuit occurred at the end of Run 23 and led to an unplanned shutdown and extensive work to replace a damaged superconducting magnet. After an in-depth investigation, the failure was found to have started with an electrical short within a superconducting current lead. The short led to large spilling of current through auxiliary superconducting circuits...
There is growing interest in differentiable simulations that have fast execution time and yield additional gradient information of physical observables with respect to design parameters. Existing differentiable codes have focused on picking a specific codebase and then reimplementing standard simulation algorithms - matrix and symplectic drift-kick tracking. This approach can be limiting due...
Spin motion in particle accelerators obeys the Thomas-Bargmann-Michel-Telegdi (T-BMT) equation. Due to the structure of the T-BMT equation, the spin-transfer quaternion of a magnet is generally a nonlinear function of the entrance coordinates even if the phase-space motion is linear. This nonlinear function can be written as a Dyson expansion, for example as employed in the program SPRINT,...
Formation of current spike in electron bunch has direct implication for attosecond pulse generation in XFEL. In this paper, we present start-to-end simulation for tunable, short current spike generation in the LCLS copper linac using photocathode laser shaping. Our approach uses two stacked laser pulses—a long and a short pulse—to imprint a small modulation in the electron bunch as it is...
The Argonne Wakefield Accelerator (AWA) facility’s drive-beam linear accelerator can generate electron bunches at a wide range of charge - from 100 pC to 100 nC. This gives us a unique opportunity to study selective transverse collimation as a method to increase beam brightness using various initial bunch charges. This paper presents numerical modeling of the scheme. Simulations were performed...
Laser switched photocathode sources are typically used to produce trains of polarized electron bunches for high performance accelerators. This paper consid-ers two high brightness, high charge-per-bunch, e-beam injector approaches that utilize laser gated cath-odes followed by DC beam acceleration sections com-prised of 1-3 grading electrodes. The use of grading electrodes provides reliable...
The Electron-Ion Collider (EIC) employs a flat hadron beam to achieve high luminosity, with the proton beam's vertical emittance being an order of magnitude smaller than its horizontal one. This small emittance ratio makes the vertical emittance highly sensitive to external noise. This study examines electron beam size ripple, a narrow-band noise centered around 60 Hz in the US. Through...
The Electron-Ion Collider (EIC) is a next-generation accelerator complex designed to enable high-luminosity collisions between highly polarized electrons and light ions (e.g., He-3). A central component of its Electron Injection System (EIS) is the Rapid Cycling Synchrotron (RCS), which accelerates a single 28 nC electron bunch from 750 MeV to 5, 10, or 18 GeV using an array of 591 MHz...
The design of accelerator lattices involves evaluating and optimizing Figures of Merit (FoMs) that characterize a beam’s properties. These properties—hence the FoMs—depend on the many parameters that describe a lattice, including the strengths, locations, and possible misalignments of focusing elements. Often what is required is the gradient of the FoM with respect to each of the parameters....
Nonlinear focusing elements enhance the stability of particle beams in high-energy colliders via Landau Damping, a phenomenon that acts through the tune spread these elements introduce. This experiment at Fermilab's Integrable Optics Test Accelerator (IOTA) aims to investigate the influence of nonlinear focusing elements on transverse beam stability by employing a novel method to directly...
At the Los Alamos Neutron Science Center (LANSCE), the injection system of the Proton Storage Ring (PSR) utilizes charge exchange via a stripping foil to convert H⁻ ions into H⁺. While beam losses caused by partially stripped neutral hydrogen atoms are a primary concern, interactions between the circulating beam and the injection foil also play a significant role in overall beam loss. Each...
The longitudinal compression of intense proton bunches with strong space-charge force is an essential component of a proton driver for a muon collider. We propose a proton bunch compression experiment at the Integrable Optics Test Accelerator (IOTA) storage ring at Fermilab to explore optimal radio frequency (RF) cavity and lattice configurations. IOTA is a compact fixed-energy storage ring...
JuTrack is a high-performance accelerator modeling and particle tracking package developed in the Julia programming language. With compiler-level automatic differentiation (AD), JuTrack enables fast and precise derivative computations for arbitrary differentiable simulation functions. It supports efficient modeling of complex collective effects such as space-charge forces, wakefields, and...
At the Los Alamos Neutron Science Center (LANSCE), accurate beam transport modeling is essential to understand the nature of beam instabilities and losses. The model analysis enables significant improvement in beam transport tuning. It is the key element in ensuring the beam envelope remains constrained and that the bunch structure is preserved as it traverses the distance from the 800-MeV...
We explore the possibility of using lasers to control the bunch intensity of electron and positron beams in high-energy colliders through Compton backscattering. We also investigate the use of hollow-core lasers for electron and positron beam collimation. This technology would allow for much higher beam intensities at colliders without the risk of damage to a physical collimation system.
Insertion Region 2 (IR2) of the Relativistic Heavy Ion Collider will be modified to provide effective cooling for the Electron-Ion Collider (EIC). This paper summarizes the update of the HSR-IR2 lattice design to meet the evolving requirements of the EIC. The geometry has been redesigned to satisfy the yellow-to-yellow configuration, while also accommodating future integration of the 41 GeV...
Nonlinear integrable optics of the type proposed by Danilov and Nagaitsev place strict constraints on the lattice parameters in the matching section outside of the nonlinear insert. In particular, the effects of energy spread in the beam have significant effects on the stability of the system. Typical chromatic compensation using sexupoles has significant perturbative effects on the dynamics...
A transfer line has been designed for the Electron-Ion Collider (EIC) to transport electron bunches from the linac to the Rapid Cycling Synchrotron (RCS). In its initial operational stage, the line accommodates 1¿nC electron bunches directly from the linac. To support a future upgrade involving a Beam Accumulator Ring (BAR), which will stack individual bunches to form high-charge 28¿nC...
The Electron-Ion Collider (EIC), a next-generation accelerator facility, is being jointly developed by Brookhaven National Laboratory (BNL) and Jefferson Lab (JLab), and will be constructed at BNL. The EIC design builds upon the existing RHIC heavy-ion infrastructure, transforming the RHIC rings into the Hadron Storage Ring (HSR) with necessary modifications. To ensure optimal performance, it...
In this study, we present the latest measurements of intrabeam scattering (IBS) effects at NSLS-II and compare them with particle tracking simulations using ELEGANT. The growth of horizontal and vertical emittances, as well as bunch length and energy spread, is observed as a function of single-bunch current. Simulations, including IBS and longitudinal wakefields modeled using a broadband...
During the 2022 RHIC polarized proton run a total of 16 vernier scans were performed at 100 GeV per beam. In this type of scan, where one beam is swept in steps across the other, the interaction rate as a function of distance between the two beams is recorded. The interaction rate is measured by the zero degree calorimeter (ZDC) which is located on the non-IP side of the DX magnet between...
The Fermilab Linac delivers 400$\,$MeV, 25$\,$mA H$^-$ beam to a rapid cycling synchrotron called the Booster. Parameters of the Linac beam affect Booster performance and therefore quantifying them is important. The longitudinal bunch parameters are reconstructed using a Bunch Shape Monitor (BSM) installed in the middle of the Linac. For that, the bunch length is measured as a function of the...
Simulations, analysis, and measurements are performed on the BNL Booster’s third integer resonance extraction to the NSRL line, which uses a constant optics slow extraction method. In this method, ring dipoles and quadrupoles are changed synchronously for a coasting beam, which aids in maintaining a fixed separatrix orientation through the spill. Simulations show that the outgoing beam has a...
The mitigation of the effects of coherent synchrotron radiation (CSR) is a key challenge in generating high brightness beams. Shielding by parallel plates installed in the dipole magnet vacuum chambers shows promise, both in simulation and experiment* at small shielding gap separations. In this work, we consider a beam traversing a chicane with larger cm-scale separations on each dipole,...
Mu2e is an upcoming experiment at Fermilab that relies on the slowly extracted 8 GeV proton beam from the Delivery Ring. The experiment imposes strong requirements on the spill uniformity. To address these requirements, the fast spill regulations system is being developed and commissioned. To inform this development and optimize the system performance we are carrying out the detailed...
The Electron-Ion Collider (EIC) is the next-generation accelerator facility to be built at the Brookhaven National Laboratory. To achieve EIC’s performance goals, an Energy Recovery Linac (ERL) cooler using Coherent electron Cooling (CeC) is designed to maintain the low emittance of the hadron beam. The ERL cooler requires high-current electron beams with low emittance and a uniform beam...
The Ghost Collider makes use of unique “ghost” bunches, which are electrically neutral combinations of electrons and positrons within the same RF bucket, eliminates the beam-beam effects typically present at the interaction point (IP) in conventional colliders. This allows for the novel possibility of placing multiple interaction regions in series, achieving additive luminosity without...
In this work we cover some of the newer techniques developed to measure the effects of a gear changing system maintained in DESIREE at Stockholm University. Gear-changing is a collider synchronization method where two rings with different harmonic numbers in them maintain collisions through different velocities, pathlengths or a combination of the two. This system has been demonstrated using...
Stangenes Industries is developing a novel klystron driver capable of peak modulator powers of 160MW and average powers of 320kW to drive a variety of high-powered electron-sources. The all-solid-state modulator consists of Marx-generators driving parallel primaries of a pulse transformer achieving output voltages of over 500kV. Over 3000 hours of internal lifetime testing on the primary...
A measurable chaos indicator is used as the online optimization objective in tuning a complicated nonlinear system - the National Synchrotron Light Source-II (NSLS-II) storage ring. Through analyzing the Shannon entropy in measured Poincar$\acute{e}$ maps, not only can the commonly used nonlinear characterizations be extracted, but more importantly, the chaos can be quantified, and then used...
One of the options to bring electron cooling to high energies is to employ an electron storage ring, which utilizes damping wigglers to counteract emittance growth of electron bunches used to cool hadrons. An example of such a cooler is the Ring Electron Cooler (REC) that can find potential future applications in Electron Ion Collider. The REC is designed to operate at 150 MeV and requires...
The Side-Coupled Linac (SCL) section of the FNAL linac accelerates the beam from 116 MeV to 401.5 MeV, operating at 22-24 mA beam current. Transverse focusing is performed by 32 quadrupoles, and the beam orbit is guided by 19 dipole correctors and measured by 29 BPMs. The bunch length is measured in a single location by a Bunch Shape Monitor (BSM). This paper presents a three-step...
Accurate measurement of electron beam emittance is essential for optimizing high-brightness electron sources. The Pinhole Scan Technique measures the 4D phase space and hence the emittance by measuring the beam profile after clipping the beam using a pinhole followed by a drift section and then scanning the beam over the pinhole. This technique has been implemented in low (< 200 keV) beamlines...
Achieving the ambitious luminosity target at the proposed Future Circular Collider e+e- (FCC-ee), collisions with high intensity and small beam size are required, limiting the choice of design parameters. As a result, the beam dynamics at the FCC-ee will be dominated by beam-beam effects at collisions, and the interplay of these with various other beam dynamical effects in the machine, such as...
The Hadron Storage Ring of the Electron-Ion Collider will feature 6 Siberian snakes placed at the start of each arc to coherently cancel spin precession from diametrically opposite arcs in the ring. To avoid spin-orbital resonances, the alternating sum of the rotation axes of all snakes is 90 degrees, ensuring the closed-orbit spin tune is ½ and sufficiently far away from betatron tunes and...
This work presents new insights into the formation and propagation of solitons in the University of Maryland Electron Ring (UMER), using a combination of theory, Particle-In-Cell (PIC) simulation, and experimental validation. Soliton dynamics in the electron beam are modeled via the Korteweg–de Vries (KdV) equation, capturing the balance between nonlinearity and dispersion inherent in...
We present preliminary analysis results from a recent experiment investigating CSR shielding effects on a beam propagating through a chicane compressor. The experiment was conducted at the Argonne Wakefield Accelerator (AWA) facility. Two identical doglegs with reversing quadrupoles—flip the beam—allow the beamline to function as a chicane. Shielding gaps of 1, 2 , and 3 cm were tested using...
Hadron Collider Rings offer unprecedented opportunities to address fundamental scientific questions in particle and nuclear physics. To achieve these ambitious goals, the colliders must deliver exceptionally high levels of luminosity, hence require high intensity hadron beam in the ring, which leads to high beam-beam parameter, as well as comparable space charge effects.
This study focuses on...
Significant progress has been made in both hardware development and simulation capability to shorten the proton bunch width delivered to the Lujan Center at LANSCE via the Proton Storage Ring (PSR). We have successfully demonstrated operation of the PSR RF buncher at 5.6 MHz, doubled from the standard running condition, to accumulate the shorter beam pulse. A quick switch between two modes is...
We present a preliminary lattice based on a bottom up design for a rapidly cycling synchrotron (RCS) accelerator chain for a multi-TeV muon collider based at Fermilab. The RCS rings range in circumference from 6.28 km (that of the Tevatron) to 15.5 km (the current estimate for the maximum that can be accommodated at the Fermilab site). Each ring is either a conventional RCS (consisting of iron...
Nonlinear beam dynamics is essential for a low emittance complex bend lattice. Therefore, a multi-objective optimization to simultaneously achieve a large dynamic aperture and momentum aperture is needed, although it is becoming increasingly challenging. In this paper, we discuss the search for optimal arrangement of chromatic sextupole and octupoles as well as optimal tunes of the ring. We...
The muon collider (MuC) holds strong potential for reaching the 10 TeV energy frontier but introduces several technical challenges. Ionization cooling is essential to reduce beam emittance and achieve required luminosities. As muons lose energy in absorbers, normal-conducting RF cavities restore it. However, strong magnetic fields—needed for beam focusing—increase the risk of RF cavity...
We discuss selection of ion sources for the LANSCE Accelerator Modernization Project (LAMP). LANSCE currently operates both an H+ and H− ion source, providing beams to five independent user facilities. The H+ source is a duoplasmatron that provides protons for the Isotope Production Facility (IPF). The H- source is a surface-converter ion source configured with two tungsten hot filaments that...
In this study, we use tracking simulations to investigate synchrotron phase-space injection for electron accumulation in the electron storage ring of the Electron-Ion Collider. Our simulation model incorporates both beam-beam interactions and lattice nonlinearities. Specifically, we examine how particle loss depends on various parameters. Our results demonstrate the feasibility of synchrotron...
We present a study of microbunching amplification in linear accelerators, focusing on the combined effects of coherent synchrotron radiation (CSR) and longitudinal space charge (LSC). We also investigate the role of a laser heater, which is designed to suppress microbunching by decreasing the relative correlated energy spread early in the beamline. Simulations are performed for the FACET linac...
The LANSCE Accelerator Modernization Project (LAMP) plans to replace the two existing 750-keV Cockcroft Waltons by a single radio-frequency quadrupole (RFQ), and to install a new 100-MeV drift-tube linac (DTL). LAMP will simultaneously produce H+ and H- beams with different timing patterns to serve multiple experimental facilities. A low energy beam transport (LEBT) is designed to transport H+...
In this study, we present a comparative analysis of passive higher-harmonic cavity (HHC) simulations with beam loading compensation using the particle tracking codes ELEGANT and SPACE. By cross-verifying results from both codes, we assess their accuracy in modeling beam dynamics under passive HHC operation for different filling patterns. Our findings demonstrate consistent outcomes between...
This paper presents a simulation-based study of single-bunch dynamics at the injection energy of 23.8 GeV for protons in the EIC hadron storage ring, focusing on the impact of space-charge–driven instabilities. The analysis demonstrates that at this energy, the proton bunch experiences significant transverse space-charge forces, which can reduce the stability margin in the presence of the...
An Energy Recovery Linac (ERL) based cooler, using Coherent electron Cooling (CeC) is being designed for cooling hadron beams of the Electron-Ion Collider (EIC). The ERL design utilizes highcurrent, high-brightness electron beams with low emittance and a uniform longitudinal distribution for efficient hadron cooling. This is designed to operate in two modes to accommodate cooling requirements...
We present a simulation study to support the planning of experimental demonstrations of transverse wiggler-based correlation control. While previous simulations confirmed the feasibility of this approach, they did not incorporate realistic field maps of the transverse wigglers. In addition, the impact of various jitter and error sources—key concerns for experimental implementation—has not been...
We present start-to-end simulation study of the transport of a few pico-Coulomb, nanometer-emittance beam through an emittance exchange (EEX) beamline. EEX with nanometer-emittance beams has potential to enable research opportunities utilizing tunable and high quality attosecond bunches and nanometer-scale longitudinal bunch trains. To account future possibility of experimental demonstrations,...
Jefferson Lab’s Continuous Electron Beam Accelerator Facility (CEBAF) is currently investigating the feasibility of upgrading its maximum operating energy using Fixed-Field Alternating-gradient (FFA) recirculating arcs to increase the total number of recirculations the beam through the pair of LINACs. These FFA arcs will be composed of permanent magnets, with small Panofsky-style multipole...
We provide updates on the community-driven Design Study for a 10 TeV pCM Wakefield Accelerator Collider. The Design Study is motivated by the 2023 P5 Report calling for the “delivery of an end-to-end design concept, including cost scales, with self-consistent parameters throughout" targeting the energy frontier. The Design Study leverages recent experimental and theoretical progress from a...
The Zgoubi simulation code for beam and spin dynamics employs a numerical method based on Taylor series to integrate the Lorentz and Thomas-BMT equations, optimizing computational efficiency while ensuring high accuracy and robust preservation of motion invariants. In this work, we developed and implemented an adaptive step-size Runge-Kutta (RK) integrator into Zgoubi to tackle growing...
In this work, we present the investigation of transit time of particles in the non-linear third-integer resonant extraction process. Transit time is defined as the number of turns a particle takes to get extracted once it is in the unstable region in the phase space, i.e., outside the triangular separatrix in case of third-integer resonance. The study of transit time is important because...
Ultimately, accurate time of arrival determination of laser pump and electron beam probe will determine the temporal resolution of the SLAC MeV-Ultrafast Electron Diffraction* (MeV-UED) instrument, and therefore methods to achieve this at femto-second scales is an ultrafast science enabler. Interferometry of THz based e-beam and pump laser THz signals is a natural path towards this goal. As a...
The Electron-Ion Collider (EIC), to be constructed at Brookhaven National Laboratory, will collide polarized high-energy electron beams with polarized proton and ion beams, achieving luminosities of up to 1 × 10^34 cm^−2 s^−1 in the center-of-mass energy range of 20–140 GeV. We have studied the impacts of various machine noises on beam emittance growth in the presence of beam-beam...
Differentiable simulations are in demand in accelerator physics, demonstrating order-of-magnitude improvements for complex tasks such as many-parameter optimization for accelerator working points and reconstruction of hard-to-measure quantities. At its core, a differentiable simulation does not only solve a forward problem, but additionally provides gradients of output parameters (e.g. beam...
The accelerating segments in the Facility for Rare Isotope Beams (FRIB) linac contain superconducting RF cavities accelerating the beam and superconducting solenoids providing transverse focusing. We have studied the transverse emittance growth in the post-stripper linear accelerating segment of the FRIB linac. To understand the cause of the emittance growth we employ a macroparticle tracking...
The Electron-Ion Collider (EIC), to be constructed based off the existing RHIC facility, will collide electrons with multiple species of hadrons. The Hadron Storage Ring (HSR), based largely on the Yellow RHIC ring, will accommodate three times the number of bunches compared to RHIC. A completely new HSR injection system will be developed to meet these requirements. This report presents the...
We investigate vertical emittance growth in the Electron-Ion Collider (EIC) arising from intrabeam scattering (IBS) diffusion through beam-beam interactions. Using weak-strong simulations, we demonstrate that when horizontal noise is introduced, vertical emittance increases even in the absence of direct vertical diffusion. This behavior is attributed to resonance streaming around the...
