bluuebunny/crossref_metadata_2025_split huggingface dataset:
Symplectic neural surrogate models for beam dynamics
Authors: Huang C-K , Tang Q , Batygin Y K , Beznosov O , Burby J , Kim A , Kurennoy S , Kwan T , Rakotoarivelo H N 
Published: January 2024

Abstract
Development of robust machine-learning (ML) based surrogates for particle accelerators can significantly benefit the modeling, design, optimization, monitoring and control of such accelerators. It is desirable that the surrogate models embed fundamental physical constraints to the interaction and dynamics of the beams, for which an accelerator must be designed to operate upon. We implement and train a class of phase space structure-preserving neural networks — Henon Neural Networks (HenonNets) [1], for nonlinear beam dynamics problems. It is demonstrated that the trained HenonNet model predicts the beam transfer matrix to a reasonably good accuracy while strongly maintaining the symplecticity. To explore such model’s applicability and flexibility for high brightness or intensity beams, we further test it with beam dynamics in the presence of electrostatic and radiative collective effects. Our results indicate that HenonNet may be used as a base ML model for the surrogate of complex beam dynamics, thus opening up a wide range of applications.
A machine learning approach to shaping magnetic fringe fields for beam dynamics control
Authors: Gallagher T , Wolski A , Muratori B D 
Published: January 2024

Abstract
Fringe fields at the entrances and exits of multipole magnets can adversely affect the dynamics of particles in an accelerator, but there is also the possibility that fringe fields could be used to enhance accelerator performance. Design work could benefit from computational tools for constructing realistic models of multipole fringe fields at an early stage in the design process; and methods for relating the magnet geometry to the field shape and to the beam dynamics would also be of significant value. We explore novel techniques to produce magnet designs that satisfy specific requirements for the beam dynamics. Machine learning tools are used to link properties of the beam dynamics in the fringe fields to the magnet geometry in an efficient way.
Improvement of the longitudinal phase space tomography at the J-PARC synchrotrons
Authors: Okita H. , Tamura F. , Yamamoto M. , Nomura M. , Shimada T. , Saha P. K. , Yoshii M. , Ohmori C. , Sugiyama Y. , Hasegawa K. , Hara K. , Albright S. , Kelliher D. J. 
Published: January 2024

Abstract
The longitudinal phase space tomography, which reconstructs the phase space distribution from the one-dimensional bunch profiles, is used in various accelerators to measure longitudinal beam parameters. At the J-PARC, an implementation of the phase space tomography based on the Convolution Back Projection method (CBP) has been used to measure the momentum spread of the injected beam. The method assumes that the beam distribution rotates without significant deformation during the synchrotron oscillation. Because of the nonlinearity of synchrotron motion with sinusoidal RF voltage, the method can be used only in limited situations such as small amplitude synchrotron oscillation. Algebraic Reconstruction Techniques (ART) in conjunction with particle tracking, which is implemented in the CERN’s tomography code, allows accurate reconstructions even for nonlinear large amplitude synchrotron oscillations. We present the overview of the application of the CERN’s tomography code to the J-PARC synchrotrons. The results of benchmarking are also reported.
Cherenkov diffraction radiation dielectric button characterization via a slab-line
Authors: Pakuza C , Wendt M 
Published: January 2024

Abstract

Cherenkov diffraction radiation is generated when a charged particle beam passes in close proximity to a dielectric target, and is currently being studied and developed for various non-invasive beam instrumentation applications at CERN. One such instrument is a beam position monitor (BPM) composed of four cylindrical dielectric inserts. A challenge of using the conventional stretched wire technique to characterize the BPM up to high frequencies is the coupling of unwanted higher order modes (HOM) into the inserts that are dielectric-loaded circular waveguides. To minimize the generation of HOMs and excite mainly the transverse electromagnetic (TEM) mode as a model of the beam field, a set-up comprising a dielectric insert mounted on a slab line with 50 Ω characteristic impedance was tested. The results and comparison with numerical simulations in CST are be presented.
New digital low-level RF controls based on the Red Pitaya STEMlab for the TLS Linac system
Authors: Cheng Y S , Lee S H , Wu C Y , Liao C Y , Liao J K , Chen J , Hu K H , Hsu K T 
Published: January 2024

Abstract
The Linac system at Taiwan Light Source (TLS) has been in operation for almost a quarter of a century and requires upgrades to improve its reliability. To achieve this, some components of the control system have been replaced with new digital low-level RF control units that use emerging technologies. A new unit is based on the open-source hardware platform which is named “Red Pitaya STEMlab” and offers a compact size and low power consumption. The unit features DAC (Digital-to-Analog Converter) blocks for downloading arbitrary waveforms with external trigger play and ADC (Analog-to-Digital Converter) blocks for waveform acquisition, enabling the development of real-time diagnostic toolkits. The new low-level RF control interface has been fully integrated into the existing EPICS software framework for system integration. The new digital low-level RF control system supports I/Q (in-phase/quadra-ture-phase) data with online amplitude and phase set-tings, and a waveform digitizer for inspecting low-level RF signals from the klystron modulator. Specific graphical applications have been designed and integrated into the existing operation interfaces. The system has been successfully achieved during routine operations. This paper describes the details of these efforts.
Superconducting multipole triplet field measurements
Authors: Esper A , Stodel M H , Savajols H , Authier M , Aburas M , Carville F , Drouart A , Jacquot B , Lefevre A , Esnault F 
Published: January 2024

Abstract
This paper presents magnetic field measurements for the Superconducting Multipole Triplets (SMT) prototypes of the Super Separator Spectrometer (S3). These advanced magnets, based on innovative concept design, generate magnetic fields of quadrupole, sextupole, octupole, and dipole. Magnetic field measurements have been conducted with a prototype mapping system to align the magnets and assess their performance. Moreover, detailed information on the experimental setup will be presented along with magnetic field analysis on the SMT’s multipoles.
Handling the Functional Features of Accelerator Components Using ISO GPS Situation Features
Authors: Nicquevert B , Rey F 
Published: January 2024

Abstract
The building blocks of a scientific facility based on particle beams comprise magnets and electro-magnetic devices. The optical design usually imposes a demanding accuracy with respect to their theoretically exact position and orientation. It happens that the functional features are either not clearly defined – what is the « axis » of a magnet –, or not explicitly used along their lifecycle. Improving how to handle these functional features would contribute to meeting demanding challenges. The European Spallation Source (ESS) is aiming at providing a powerful proton linear accelerator and a target system to produce pulsed neutrons. The challenging complex design and integration yielded to introducing a tool shared in common by all stakeholders along the lifecycle: the “situation features”, as defined in ISO GPS (Geometrical Product Specifications) standards. They are here developed, and extended to beyond-mechanics use cases. Two examples of fiducialization and installation phases are presented for neutron beam guides and quadrupole magnets. Perspectives of generic use are also highlighted.
SuperKEKB personnel protection system
Authors: Mimashi T , Ono M , Kudo K , Tanaka M , Tanaka N , Ogawa E 
Published: January 2024

Abstract
The Super-KEKB[1] personnel protection system (PPS) takes care of not only Super-KEKB accelerator, but also Photon Factory - Advanced Ring (PF-AR), Positron Damping Ring (PDR)[2] and their beam transport lines (BT)[3]. The logic of the PPS has been changed to adapt the new accelerator operation scheme. The Experimental Physics and Industrial Control System (EPICS) was introduced into the PPS. Many tools developed under EPICS environment are used.
A two harmonics circuit for the powering of the very fast RCS (Rapid Cycling Synchrotron) of the muon collider accelerator
Authors: Boattini F. , Aguglia D. , Brauchli G. , Bottura L. 
Published: January 2024

Abstract
This paper analyses the application of a two harmonics circuit with additional active filter for the powering of the four RCS stages of the muon acceleration to the ultimate 10 TeV energy level.
LHC low-beta quadrupole magnets: cryogenic refrigeration capacity and improved controls for luminosity optimization
Authors: Bradu B. , Brodzinski K. , Gahier V. , Ferlin G. , Younes-Cronnier M. 
Published: January 2024

Abstract
The LHC low-β quadrupole magnets, also known as “Inner Triplets”, are the final focusing magnets located on each side of LHC interaction points. The current LHC Inner triplets are NbTi superconducting magnets operated in superfluid helium at 1.9 K and use a bayonet heat exchanger to extract the heat deposited by the secondary particles coming from the proton collisions. The dynamic heat loads in Inner Triplet are consequently proportional to the LHC luminosity and due to the recent upgrades of LHC and its injectors, the cryogenic capacity limit can be reached around ATLAS and CMS experiments where the luminosity can go slightly beyond the LHC ultimate luminosity. First, this paper summarizes the history of the Inner Triplet cryogenics with the different tests performed in the past to assess their cooling capacity. Then, the different techniques implemented in the cryogenic control system to handle the luminosity transients are detailed and finally, a new control interaction between the cryogenic system and the LHC luminosity server is detailed to optimize online the LHC luminosity.
Study on the vacuum properties of laser-etched oxygen-free copper
Authors: Zhang W L , Ma W J , Wang S H , Fan L , Ge X Q , Bian B Y , Fang J W , Wang Y 
Published: January 2024

Abstract
The performance of operating particle accelerators has been seriously affected by the electron cloud (e-cloud) effect. The secondary electron emission (SEE) and the e-cloud can be effectively suppressed through laser-etching the inner surface of the vacuum chamber. Oxygen-free copper (OFC) has become the first choice for the vacuum chambers of modern accelerators due to its high electric and thermal conductivity and effective radiation shielding property. It is necessary to study the vacuum properties of the laser-etched OFC for the application in the particle accelerators. In this paper, the photon stimulated desorption (PSD) yield and the outgassing rate of the laser-etched OFC were measured. The results show that the laser-etched OFC presents lower PSD yield compared to the untreated OFC, while the outgassing rates of the laser-etched and unetched samples are similar.
A new NEG coating setup with travelling thin solenoids for the SLS 2.0 complex vacuum chambers
Authors: Kirchgeorg N , Buchmann J , Gaiffi N , Ganter R , Huber P , Magjar M , Rosenberg C , Stephan D 
Published: January 2024

Abstract
The 288 m long Storage Ring of Swiss Light Source 2.0 (SLS 2.0) consists of several vacuum chambers with unique geometries. Complicated features, with many changes in the cross sections, are essential to provide the best impedance matching, and to allow synchrotron light extraction under the tight geometrical constraints. In order to speed up the commissioning time, it was decided to coat most of the vacuum chambers with non-evaporable getter (NEG) material. A new magnetron sputtering setup has been developed in Paul Scherrer Institut (PSI), where the plasma length, defined by thin solenoids, is relatively small. The solenoids are continuously travelling over the entire vacuum chambers more than hundred times per coating process with an average speed of 4 mm/s to assure the best possible thickness uniformity and to limit the cathode heat up. Flexibility provided by this solution allows to coat various vacuum vessels in one assembly. This paper will describe this NEG coating setup and show results on SLS 2.0 vacuum chambers.
Upgrade of the medium energy dump geometry for the SPIRAL2 single bunch selector
Authors: Giacomo M Di , Barthe-Dejean C , Jacquot B , Leloir S , Orduz A K 
Published: January 2024

Abstract
The medium energy beam transport of the SPIRAL2 superconducting linac contains a single bunch selection system equipped with a 7.5 kW beam dump. This device, originally designed with a long flat slope to decrease the power density so that the maximum operating temperature was 170 °C, was impacted by Coulomb scattering generating two side effects: heating of the downstream beam transport components and degrading of the beam current measurement uncertainty. The paper relates the way these two problems were solved.
Energy saving magnets for beam lines
Authors: Rossi L. , Mariotto S. , Sorti S. 
Published: January 2024

Abstract
Beam lines magnets for high rigidity particles can have a large power dissipation. In presence of a high duty cycle, this translates in a considerable amount of energy waste. The call for sustainability of large research infrastructures, like particle accelerator centers, and the recent increase of the cost of energy, require to take measures to reduce the energy consumption, even at cost of moderate investment. A study program called ESABLIM (Energy SAving Beam LIne Magnets) has been set up at the LASA lab of University and INFN Milano, aimed at revamping existing normal-conducting magnets for beam lines with the target of cutting the peak power by a factor 10 to 20 and reducing the energy consumption by factor 5 or more. The idea is to replace the water cooled coils of iron-dominated magnets with new superconducting coils cooled at 10-20 K by means of a cryocooler, while to reusing the iron yoke pole assembly. We envisage using MgB2 for its moderate cost, however, high temperature superconductors (HTS) will also be considered as conductor. We present the first advanced design for revamping of a large bending dipole in a hadron therapy center, and the conceptual design for magnets in a nuclear physics laboratory and we try to define the domain where this transformation of normal-conducting into super-ferric magnets can be technically and economically advantageous.
Measurements of the Variation of RFKO Extracted Beam Current for Hitachi Proton Therapy and Carbon Therapy Synchrotrons and Implications for Particle Therapy
Authors: Furutani Keith M. , Beltran Chris J. 
Published: January 2024

Abstract
Measurements of the extracted beam current (BC) for a Hitachi Carbon Therapy Synchrotron and a Hitachi Compact Proton Therapy Synchrotron are reported for the nominal extracted beam current (BC0) of

10

m
M
U

m
sec

, which was chosen since it is the magnitude of the clinical BC0, and a sample rate of 5 μsec (Carbon) and 8 μsec (Proton). A Noise Power Spectrum (NPS) analysis identifies the source of variation to be beam or power supply related. The rise time in the BC has been modeled and its effect on beam delivery time simulations have been estimated. The impact of the variation in BC from BC0 is shown to cause potentially significant dosimetric uncertainties in treatment delivery for modern particle therapy accelerators using fast Scanning Magnet (SCM) if plans are not simply beam current moderated or robustly optimized. The variation in beam current is shown to be inconsequential for medical physics quality assurance and commissioning measurements using properly biased ion chambers.
Proton FLASH irradiation setup for preclinical studies at HZB
Authors: Kourkafas G , Bundesmann J , Denker A , Dittwald A , Fanselow T , Heufelder J , Weber A , Mühldorfer P 
Published: January 2024

Abstract
The HZB cyclotron continues to provide protons for eye-tumor treatment in collaboration with the Charité – Universitätsmedizin Berlin after 24 years and more than 4400 patients so far. With the perspective of broadening its research capabilities in the field of radiation therapy, intensive effort has been dedicated towards proton FLASH irradiation, which requires ultra-high dose rates or beam intensities.
By combining a fast and reliable switch-off mechanism, accurate dosimetry, and a double-scattering beam nozzle with a static 3D-printed range modulator, HZB is now able to deliver a dose rate above 150 Gy/s within a flat circular irradiation field of 18mm diameter and a 27mm spread-out Bragg peak with a distal fall-off of 1mm in water. The reproducibility of the delivered dose meets the clinical acceptance criteria for a total irradiation time as low as 2.5 ms.
The first experiments with this setup were used on fibroblastic and sarcoma organoids. By adapting the design to a 35mm lateral field and using optimal accelerator tuning to increase beam transmission, similar or even higher dose rates are expected, satisfying thus the FLASH conditions for eye-tumor treatment with protons.
Calibration assessment of the PSI proton therapy Gantry 2 scanning system after 10 years of operation
Authors: Actis O , Meer D , Bula C , Mayor A 
Published: January 2024

Abstract
Sub-millimetre precision is a crucial criterion for beam delivery in Pencil Beam Scanning (PBS) proton therapy. Nowadays, most of the therapy systems use PBS technique where single beams with a regulated number of protons are delivered sequentially to different locations within the target. Beam energy defines the depth of the beam in the target and scanner magnets deflect the beam to the desired lateral position.
The PSI Gantry 2 was among the first gantries to use the PBS technique. Available clinical proton beam energies ranging from 70 MeV to 230 MeV are achieved by de-grading a 250 MeV beam, initially provided by a super-conducting cyclotron. Beam scanning is performed just before the last bending magnet producing a nearly parallel beam at iso-centre with a well-focused beam over the full scan area of 20×12 cm2. We developed a calibration algorithm for the scanner magnets in order to achieve the desirable precision of the beam in the target. Measuring the beam position with a strip ion chamber in the gantry nozzle, we parametrized the propagation of the beam to the target calculating the beam angle at different scan positions as well as all gantry angles. During 10 years of operation we performed regular Quality Assurance (QA) tests to validate parameters obtained during the system commissioning. The QA data proved a stable system operation and no parametrization update was required so far. In this contribution, we describe the calibration pro-cess of scanning magnets with respect to beam position at the isocentre and show the stability of this implementation over the time.
Magnet Technology and Design of Superconducting Magnets for Heavy Ion Gantry for Hadron Therapy
Authors: Rossi L. , Barna D. , Carloni A. G. , Matteis E. De , Farinon S. , Felcini E. , Gautheron E. , Karppinen M. , Kirby G. , Lecrevisse T. , Musenich R. , Perini D. , Prioli M. , Pullia M. , Sorti S. , Tommasini D. 
Published: January 2024

Abstract
Various initiatives in Europe have been launched to study superconducting magnets for a rotatable gantry suitable to deliver up to 440 MeV/A carbon ions for hadron therapy. One initiative is led by INFN inside an agreement with CERN, CNAO, and MedAustron aiming at designing and manufacturing a strongly curved cos θ dipole rated for 4 T central field and with a ramp rate of 0.15-0.4 T/s. Here we explore the suitability of dipole technology derived from HEP collider for a rotatable gantry that poses severe conditions on the thermal design (indirectly cooled coils). A second one is in the frame of the European program H2020-HITRIplus-WP8, aimed at exploring the feasibility of using the novel Canted Cosine Theta (CCT) concept to produce a superconducting dipole with similar characteristics. The scope is to design and built one or two prototypes with Nb-Ti rope, to see if this route could be a viable alternative. Finally in the European collaboration H2020-I. FAST-WP8 we are exploring both CCT in combined function design (dipole + quadrupole, in Nb-Ti) and the use of HTS (REBCO tapes) with CCT dipole layout, pursuing the design manufacture of small prototypes with European Industry. If HTS will be found successful, it will be a great benefit for the cryogenic design of the magnet system.
The advanced motion control system in HEPS beamline
Authors: Yue Zongyang , Lei Ge , Zhou Aiyu , Deng Xiaobao , Liu Yu , Zhang Dianshuai , Li Gang 
Published: January 2024

Abstract
In synchrotron radiation facilities such as the High Energy
Photon Source (HEPS), numerous motorized actuators are equipped on
the optics devices of HEPS beamline to manipulate the orientation of
crystals and mirrors, thereby altering the position and
characteristics of X-rays. The motion control system (MCS) plays an
important role in the optics devices of HEPS beamlines, such as
monochromator, K-B mirror and sample plants. In order to acquire
the specify properties of X-ray and satisfy the complex experimental
requirements, MCS must have the ability to handle the complicated
control demands. Therefore, HEPS has developed a standardized
motion control system for synchrotron radiation applications, which
is a distributed system based on EtherCAT fieldbus. The hardware of
this system consists of the control unit and driver unit, which has
the flexibility to suit for different applications. The software of
MCS is designed under the Experimental Physics and Industrial
Control System (EPICS), which is very popular in synchrotron
radiation facilities all over the world. In this paper, the
performance tests of IOC software were demonstrated, and a few
flyscan applications were given, which include spiral scan, raster
scan and position event trigger, to demonstrate the feasibility and
effectiveness of this system.
Silicon Photomultiplier selection for Large Array of Imaging Atmospheric Cherenkov Telescopes
Authors: Lu R. , Zhang L. , Ge M.M. , Zhang S.S. , Hor Y.K. 
Published: January 2024

Abstract
A Large Array of imaging atmospheric Cherenkov Telescopes
(LACT) will be constructed at the Large High Altitude Air Shower
Observatory site to explore the nature of PeV gamma-ray sources. The
cameras of LACT will use Silicon Photomultipliers (SiPMs) as the
photodetector. A dedicated test system was built to select SiPMs for
LACT. The characteristics of six SiPM models from three
manufacturers (Hamamatsu, Joinbon, and ON Semiconductor) were
evaluated. Based on the characteristics of the candidate SiPMs and
their preamplifiers, a Wiener-deconvolution algorithm is implemented
to correct the pileup of the SiPM output pulses. The measurement
methods and results for breakdown voltage, gain, dark count rate,
optical crosstalk, and afterpulsing of the candidate SiPMs are
reported in this article.
Network mechanism for generating genuinely correlative Gaussian states*
Authors: Bai Zhaofang , Du Shuanping 
Published: January 2024

Abstract
Generating a long-distance quantum state with genuine quantum correlation (GQC) is one of the most essential functions of quantum networks to support quantum communication. Here, we provide a deterministic scheme for generating multimode Gaussian states with certain GQC (including genuine entanglement). Efficient algorithms of generating multimode states are also proposed. Our scheme is useful for resolving the bottleneck in generating some multimode Gaussian states and may pave the way towards real world applications of preparing multipartite quantum states in current quantum technologies.