bluuebunny/crossref_metadata_2025 huggingface dataset:
Transforming scalable synthesis of graphene aerosol gel material toward highly flexible and wide-temperature tolerant printed micro-supercapacitors
Authors: Raihan Kh M Asif , Sahoo Surjit , Nagaraja Thiba , Sigdel Shusil , LaCroix Brice , Sorensen Christopher M. , Das Suprem R.
Published: January 2024

The ever-growing demand for portable, bendable, twistable, and wearable microelectronics operating in a wide temperature range has stimulated an immense interest in the development of solid-state flexible energy storage devices using scalable fabrication technology. Herein, we developed additively manufactured graphene aerosol gel-based all-solid-state micro-supercapacitors (MSCs) via inkjet printing with functioning temperature in the range from −15 to +70 °C and exhibiting a super-stable and reliable electrochemical performance using interdigitated finger electrodes and PVA/H3PO4 solid-state electrolyte. The graphene aerosol gel was obtained using a scalable single step synthesis method from a gas phase precursor using a detonation process, producing a nanoscale shell type structure. The fabricated graphene aerosol gel-based solid-state MSC achieved a volumetric capacitance of 376.63 mF cm−3 (areal capacitance of 76.23 μF cm−2) at a constant current of 0.25 μA and demonstrated exceptional cyclic stability (∼99.6% of capacitance retention) over 10 000 cycles. To exploit the mechanical strength of the as-fabricated graphene aerosol gel-based solid-state MSC, its supercapacitive performance was scrutinized under various bending and twisting angles and the results showed excellent mechanical flexibility. Furthermore, to study the electrochemical performance of the as-fabricated graphene aerosol gel solid-state MSC in stringent surroundings, a broad temperature dependent supercapacitive analysis was performed as stated above. The electrochemical results of the as-fabricated graphene aerosol gel based all-solid-state MSC exhibit a highly potential route to develop scalable and authentic future miniaturized energy storage devices for IoT based smart electronic appliances.
Numerical investigation of particle dispersion and collision in a liquid jet flow
Authors: Huang Junkai , Zhao Xin
Published: January 2024

A numerical simulation with the Eulerian–Lagrangian point-particle approach is used to study the dispersion of nanoparticles in liquid jet flows. The volume of fluid method is used to simulate the motion of the gas–liquid interface. The particle motion is resolved by the Lagrangian point-particle model, and the collisions among particles are considered. According to the simulation results, the liquid jet atomization process can be divided into four different periods. Moreover, the nanoparticles lead to an increase in the liquid density and viscosity. The influence of the particle motion on the liquid jet breakup process is discussed. The simulation results show that the collisions would restrain particle dispersion. However, the motions and collisions of the particles would help the breakup of the liquid jet.
A plant flavonol and genetic suppressors rescue a pathogenic mutation associated with kinesin in neurons
Authors: Chai Yongping , Li Dong , Gong Weibin , Ke Jingyi , Tian Dianzhe , Chen Zhe , Guo Angel , Guo Zhengyang , Li Wei , Feng Wei , Ou Guangshuo
Published: January 2024

KIF1A, a microtubule-based motor protein responsible for axonal transport, is linked to a group of neurological disorders known as KIF1A-associated neurological disorder (KAND). Current therapeutic options for KAND are limited. Here, we introduced the clinically relevant KIF1A(R11Q) variant into the
Caenorhabditis elegans
homolog UNC-104, resulting in uncoordinated animal behaviors. Through genetic suppressor screens, we identified intragenic mutations in UNC-104’s motor domain that rescued synaptic vesicle localization and coordinated movement. We showed that two suppressor mutations partially recovered motor activity in vitro by counteracting the structural defect caused by R11Q at KIF1A’s nucleotide-binding pocket. We found that supplementation with fisetin, a plant flavonol, improved KIF1A(R11Q) worms’ movement and morphology. Notably, our biochemical and single-molecule assays revealed that fisetin directly restored the ATPase activity and processive movement of human KIF1A(R11Q) without affecting wild-type KIF1A. These findings suggest fisetin as a potential intervention for enhancing KIF1A(R11Q) activity and alleviating associated defects in KAND.
Study of electrical and dielectric properties as an effect of nanoparticle concentration and UV irradiation of PVA-Ag nanocomposites
Authors: Nain Aditi , Dhanda Ekta , Chahal Rishi Pal , Dahiya Sanjay
Published: January 2024

PVA incorporated with different concentrations of silver nanostructures were prepared using chemical reduction technique and these prepared nanocomposites were exposed to UV irradiation for 2, 3 and 4 h. Fundamental aim is to investigate tailoring of conductivity and dielectric parameters due to changes of concentration of nanoparticles and irradiation time. XRD was done to study structural characterization. FE-SEM and EDX were employed for structural and morphological analysis of nanocomposites. AC conductivity was observed to increase and values of dielectric constant were noticed to decrease whereas dielectric loss was observed to show increment with increasing concentration of nanostructures and UV exposure.
A relook at the GZK neutrino-photon connection: impact of extra-galactic radio background & UHECR properties
Authors: Chakraborty Sovan , Mehta Poonam , Sarmah Prantik
Published: January 2024

Ultra-high energy cosmic rays (UHECRs) beyond the Greisen-Zatsepin-Kuzmin (GZK) cut-off provide us with a unique opportunity to understand the universe at extreme energies. Secondary GZK photons and GZK neutrinos associated with the same interaction are indeed interconnected and render access to multi-messenger analysis of UHECRs. The GZK photon flux is heavily attenuated due to the interaction with Cosmic Microwave Background (CMB) and the Extra-galactic Radio Background (ERB). The present estimate of the ERB comprising of several model uncertainties together with the ARCADE2 radio results in large propagation uncertainties in the GZK photon flux. On the other hand, the weakly interacting GZK neutrino flux is unaffected by these propagation effects. In this work, we make an updated estimate of the GZK photon and GZK neutrino fluxes considering a wide variation of both the production and propagation properties of the UHECR like, the spectral index, the cut-off energy of the primary spectrum, the distribution of sources and the uncertainties in the ERB estimation.
We explore the detection prospects of the GZK fluxes with various present and upcoming UHECR and UHE neutrino detectors such as Auger, TA, GRAND, ANITA, ARA, IceCube and IceCube-Gen2.
The predicted fluxes are found to be beyond the reach of the current detectors.
In future, proposed IceCube-Gen2, Auger upgrade and GRAND experiments will have the sensitivity to the predicted GZK photon and GZK neutrino fluxes. Such detection can put constraints on the UHECR source properties and the propagation effects due to the ERB. We also propose an indirect limit on the GZK photon flux using the neutrino-photon connection for any future detection of GZK neutrinos by the IceCube-Gen2 detector. We find this limit to be consistent with our GZK flux predictions.
Shadows of loop quantum black holes: semi-analytical simulations of loop quantum gravity effects on Sagittarius A* and M87*
Authors: Jiang Hong-Xuan , Liu Cheng , Dihingia Indu K. , Mizuno Yosuke , Xu Haiguang , Zhu Tao , Wu Qiang
Published: January 2024

In this study, we delve into the observational implications of rotating Loop Quantum Black Holes (LQBHs) within an astrophysical framework. We employ semi-analytical General Relativistic Radiative Transfer (GRRT) computations to study the emission from the accretion flow around LQBHs. Our findings indicate that the increase of Loop Quantum Gravity (LQG) effects results in an enlargement of the rings from LQBHs, thereby causing a more circular polarization pattern in the shadow images.
We make comparisons with the Event Horizon Telescope (EHT) observations of Sgr A* and M87*, which enable us to determine an upper limit for the polymetric function P in LQG. The upper limit for Sgr A* is 0.2, while for M87* it is 0.07. Both black holes exhibit a preference for a relatively high spin (a ≳ 0.5 for Sgr A* and 0.5 ≲ a ≲ 0.7 for M87*). The constraints for Sgr A* are based on black hole spin and ring diameter, whereas for M87*, the constraints are further tightened by the polarimetric pattern. In essence, our simulations provide observational constraints on the effect of LQG in supermassive black holes (SMBH), providing the most consistent comparison with observation.
Isotope effects on transport characteristics of edge and core plasmas heated by neutral beam injection (NBI) in an inward shifted configuration at the Large Helical Device
Authors: Zhou H. , Xu Y. , Kobayashi M. , Shimizu A. , Seki R. , Tanaka K. , Tokuzawa T. , Yoshinuma M. , Takemura Y. , Takahashi H. , Ogawa K. , Cheng J. , Li W. , Wu D.N. , Zhu Y.J. , Luo Y. , Li Y.C. , Huang J. , Wang X.Q. , Liu H.F. , Liu H. , Zhang X.
Published: January 2024

Isotope effects have been investigated in Neutral Beam Injection (NBI) heated plasmas on the Large Helical Device with similar operational parameters between Hydrogen (H) and Deuterium (D) plasmas. Experimental results show that the global energy confinement has no significant dependence on the isotope mass under similar discharge conditions with nearly the same heating power, line-averaged density (

n
ˉ

e

) and magnetic field. For both electron and ion energy transport, the transport coefficients, which are obtained based on local power balance analysis, have analogous profiles between H and D dominant plasmas. For neoclassical

χ
e

and

χ
i

values, they are almost equal between H and D dominant plasmas in low

n
ˉ

e

discharges, whereas in high

n
ˉ

e

cases they are lower in H plasmas than those in D ones. At low

n
ˉ

e

, the electron and ion thermal transport in both H and D plasmas are dominated by neoclassical transport at a certain zone (

ρ
≈
0.6
−
0.85

), while the anomalous transport process has primary effects in the remaining area, and the density fluctuations exhibit ion temperature gradient mode nature. With increase of

n
ˉ

e

, the anomalous transport becomes prevailing and the density fluctuations propagate along electron diamagnetic drift direction. Bispectral analysis reveals that the H plasma has stronger nonlinear coupling in edge density fluctuations in both low and high density discharges, which is probably due to that the D plasma has stronger damping rate for the nonlinear interaction of turbulence. For a comparative study, the present results have been compared with those observed in the ECRH discharges (Tanaka et al 2019 Nucl. Fusion
59 126040). The reasons for the similarities and dissimilarities between these two different heating manners are not clear yet. To unravel the underlying physics, essential inputs from theories and simulations are required.
First results of running the LHC with lead ions at a beam energy of 6.8 Z TeV
Authors: Bruce R. , Alemany Fernandez R. , Argyropoulos T. , Bartosik H. , Bracco C. , Cai R. , D’Andrea M. , Frasca A. , Hermes P. , Jowett J.M. , Mirarchi D. , Redaelli S. , Solfaroli M. , Triantafyllou N. , Wenninger J.
Published: January 2024

A two-day test of operation with Pb ion beams was carried out in the CERN Large Hadron Collider (LHC) in 2022, with the aim of gaining experience in view of the future high luminosity heavy-ion physics runs from 2023 onwards. The LHC experiments received the first Pb-Pb collisions at a record energy of 5.36 TeV centre-of-mass energy per colliding nucleon pair (beam energy 6.8 Z TeV). Bunch trains created with a new production scheme in the injectors, including slip-stacking, were injected into the LHC, with the collimation of nuclear beams with bent crystals tested along with a new collimation scheme for collision products. This paper describes the conditions and outcomes of these tests, which are critical steps in the upgrade to higher luminosity.
Definition of tolerances and corrector strengths for the orbit control of the High-Energy Booster ring of the future electron-positron collider
Authors: Dalena B. , Da Silva T. , Chancé A. , Ghribi A.
Published: January 2024

After the discovery of the Higgs boson at the LHC, particle physics community is exploring and proposing next accelerators, to address the remaining open questions on the underlying mechanisms and constituents of the present universe. One of the studied possibilities is FCC (Future Circular Collider), a 100-km-long collider at CERN [1]. The feasibility study of this future proposed accelerator implies the definition of tolerances on magnets imperfections and of the strategies of correction in order to guarantee the target performances of the High Energy Booster ring. The efficiency of the correction scheme, used to control the orbit, directly bounds the corrector needs and magnet tolerances. Analytic formulae give a first estimation of the average RMS values of the required dipole correctors’ strengths and of the allowed magnets misalignments and field quality along the entire ring. The distribution of the correctors along the ring is simulated, in order to verify the quality of the residual orbit after the proposed correction strategy and to compare it with the analytical predictions. First specifications of the orbit correctors strength and tolerances for the alignment of the main elements of the ring are presented. The limits of the studied correction scheme and method are also discussed.
Preliminary design of the FCC-ee vacuum chamber absorbers
Authors: Morrone M. , Garion C. , Kersevan R. , Rorison S. , Chiggiato P.
Published: January 2024

In the FCC-ee study, it is proposed that electron and positron beams circulate at high current and high energy in a 92-km circumference twin ring. The present operational scenario foresees a first running step at an energy of 45.6 GeV and around 1.4 A current, which would generate copious amounts of synchrotron radiation (SR) power and flux. To guarantee a quick decrease of the photon desorption yields and so a fast vacuum conditioning, it has been proposed to use localized SR absorbers along the vacuum chamber, spaced about 5 m apart. This would also help contain the high-energy Compton-scattered secondaries once the beam energy is increased up to 182.5 GeV, later in the experimental program. In the preliminary design of FCC-ee vacuum chamber absorbers presented in this work, the SR thermal power is intercepted along around 100 mm of slanted surface. The temperature distribution in the adsorbers is estimated by Finite Element Analysis (FEA) and needs to be assessed to avoid any liquid-gas phase change within the water-cooling circuit. The cooling channels contain a twisted tape that increases the turbulence of water. This results in the desired heat transfer coefficient. The mechanical deformations due to the non-uniform temperature map are presented and analysed as well.
The ESS𝜈SB+ Project
Authors: Tolba T , Baussan E , Dracos M , Kliček B , Ekelöf T , Olvegård M , Gazis N
Published: January 2024

The European Spallation Source neutrino Super Beam (ESS𝜈SB) is a long-baseline neutrino project that will measure the CP-violation in the leptonic sector at the second, rather than the first, oscillation maximum, where the sensitivity of the experiment is ∼3 times higher. The physics simulations have shown that the ESS𝜈SB, after 10 years of data taking, will be able to cover more than 70% of the CP-violating phase, δCP
, parameterrange with 5 σ C.L. to reject the no-CP-violation hypothesis. The expected measurement error of δCP
is smaller than 8° for all δCP
values, making it the most precise proposed experiment in the field by a large margin. The extension project, ESS𝜈SB+ to be performed between 2023 and 2026, aims in measuring the neutrino-nucleus cross-section (the dominant term of the systematic uncertainty) in the energy range of 0.2 – 0.6 GeV, using a Low Energy nuSTORM (LEnuSTORM) and a Low Energy Monitored Neutrino Beam (LEMNB) facilities.
Magnetic Design of the Commutational Magnet and Quadrupoles for PERLE Accelerator
Authors: Abukeshek R. , Abualrob H. , Stocchi A. , Perrot L. , Fomin A. , Michaud J. , Bogacz A. , Benesch J. , Jacquot B.
Published: January 2024

PERLE (Powerful Energy Recovery LINAC for Experiment) is a three turns high-power Energy Recovery LINAC (ERL) facility with 20 mA beam current and beam energy from 250 MeV to 500 MeV. It is a testbed to validate multi-turn high current ERL operation for the future LHeC and will be the first ERL for nuclear applications. In this work, the design and optimization of the commutational magnet (B-com) used to spread/combine the three beams and one series of quadrupole magnets is discussed. The B-com magnet is optimized for a 30° bending angle with harmonic content of 0.036%. The quadrupole magnets generate a field gradient of 34.15 T/m. Further studies to suppress saturation at a maximum gradient of 44.1 T/m are undergoing.
Design of A Permanent Quadrupole Magnet with Adjustable Magnetic Field Gradient
Authors: Dong S. X. , Li B. , Zhang B. S. , Wang X. Q. , Feng G. Y.
Published: January 2024

As compared to traditional magnets, permanent magnets can effectively reduce energy consumption and eliminate the impact of current ripple and the water cooling system on beam current. The use of permanent magnets in accelerators has become a new trend as permanent magnet technology has advanced. In HALF (Hefei Advanced Light Facility), we have designed a permanent magnet based on the quadrupole magnet, and the central magnetic field strength of the permanent magnet can be adjusted, indicating that single or multiple permanent magnets can be developed to replace different sizes of quadrupole magnets in accelerators, greatly improving systematization. The magnet’s mechanical design has been finalized, and the prototype of the permanent magnet will be manufactured and tested soon.
Booster conceptual design of the southern advance photon source
Authors: Huang L. , Chen J. , Han Y. , Liu W. , Liu X.
Published: January 2024

The Southern Advanced Photon Source is a proposed diffraction-limited storage ring operating at middle energy. A candidate injector includes a low energy Linac and a full energy booster. In the paper, we present the concept design of the booster, which is a high intensity synchrotron accelerator. An impedance model has been obtained and the instability threshold has been predicted.
Design of a 250 MeV linac injector system for the Southern Advanced Photon Source
Authors: Han Yanliang , Huang Liangsheng , Liu Xingguang , Jiao Yi , Wang Sheng
Published: January 2024

The Southern Advanced Photon Source (SAPS) is a 4th generation storage ring based light source under design started several years ago, which is planned to be constructed at Guangdong province at China. The equilibrium emittance of the storage ring(SR) will be below 100 pm.rad and the beam energy is determined to be 3.5 GeV. Over the past two years, the nominal current of the SR was increased from 200 to 500 mA, requiring the injector system to provide more bunch charge. Additionally, the injection beam energy for the booster has been increased from 150 to 250 MeV, which means two more accelerating cavities have to been added. This paper presents an update of the linac injector. And also a beam transfer line from linac to booster is presented.
A novel scheme based on angular dispersion-induced microbunching mechanism for harmonic generation in storage ring
Authors: Lu Yujie , Feng Chao , Wang Dong
Published: January 2024

Angular dispersion-induced microbunching (ADM) scheme was proposed to generate high harmonic coherent radiation in the storage ring with weak energy modulation amplitude. However, it is still difficult to convert the external UV seed laser into the sub-nanometer wavelength. In this paper, we proposed a novel scheme based on ADM mechanism. By properly choosing the parameters, theory and one order simulation demonstrate that it is possible to produce ultrahigh harmonic coherent radiation in the storage ring. The high harmonic conversion efficiency of the proposed scheme may open up a new opportunity to produce sub-nanometer X-ray coherent radiation in the storage ring.
Feasibility verification of ultrafast FEL generation experimental scheme based on SXFEL
Authors: Xiao Yaozong , Feng Chao , Sun Hao , Liu Bo
Published: January 2024

The photon energy in the soft X-ray range corresponds to the fundamental absorption edges of matter. Ultrashort X-ray pulses can be used to observe the breaking of chemical bonds in biochemical reactions and capture the transfer process of electrons in ultrafast physical phenomena. In this paper, the feasibility of ESASE experiments on Shanghai Soft X-ray Free Electron Laser Facility (SXFEL) is theoretically verified. The results show that the ESASE scheme can produce ultrafast light pulses on the order of attosecond, with a peak power of 450 MW. At the same time, the simulation results in this paper verify the feasibility of chirped enhanced SASE schenme based on SXFEL. The results show that compared with the ESASE scheme, the power of the radiation pulse can be greatly improved by this scheme. A relatively low energy electron beam (1.5 GeV) was used to generate about 40 GW of radiation, and the length of the radiation pulse was significantly shortened.
Enhanced harmonic generation for high-repetition-rate soft x-ray free-electron laser
Authors: Yang H , Yan J , Deng H
Published: January 2024

Externally seeded free-electron lasers are promising for generating intense, stable, and fully coherent soft X-ray pulses. An earlier study demonstrates that high brightness and coherent soft X-ray radiation can be produced based on coherent harmonic generation and superradiant principles, termed high-brightness high-gain harmonic generation (HB-HGHG). However, the seed laser at the ultraviolet region cannot induce sufficient energy modulation at high repetition rates due to state-of-the-art laser system limitations. A recently suggested self-modulation scheme shows that the peak power requirement of a seed laser can be reduced by around one order of magnitude in an HGHG setup. In this paper, we present start-to-end simulation results to estimate the feasibility of the self-modulation-enhanced HB-HGHG scheme.
Performance of laser patterned copper plasmonic photocathodes
Authors: Martinez-Calderon M , Groussin B , Bjelland V , Chevallay E , Himmerlich M , Lorenz P , Marsh B , Neupert H , Rossel R , Wuensch W , Granados E
Published: January 2024

We study ultrafast laser surface nanopatterning as an alternative to improve the photo-emissive properties of metallic photocathodes. By tailoring the physical dimensions of these surface nanostructures, one can localize the optical field intensity and exploit plasmonic effects occurring in such nanostructures. As a result, this surface nanopatterning technique can become a great tool for improving metallic photocathodes photoemission behavior enabling their use for next generation high brightness electron sources. Our goal is to investigate such surface-plasmon assisted photoemission processes with a view on simplifying the photocathode production at CERN while extending the lifetime of existing photoinjectors. The performance of two different femtosecond laser nanopatterned plasmonic photocathodes was analyzed by measuring the quantum yield with a 65kV DC electron gun utilizing 266nm laser excitation generated by a nanosecond laser with 5ns pulse duration and 10Hz repetition rate. By comparing the electron emission of the copper surface nanostructured areas with that of a flat area, our results suggest quantum yield enhancements of up to a factor of 5.
High-power experiment of a C-band photocathode gun
Authors: Wang Cheng , Tan Jianhao , Huang Xiaoxia , Xiao Chengcheng , Gao Zihe , Fang Wencheng
Published: January 2024

The C-band electron gun is an attractive option for lower emittance with compactness. In this paper, a new C-band photocathode gun has been developed. The electron gun experienced high-power test, and has preliminary reached the designed gradient on the cathode, 150MV/m with a repetition rate of 10Hz and pulse length of 2.5μs. The gun shows the potential for better performance with a higher gradient during high-power operation. Under extreme conditions, the gradient on the cathode is about 180MV/m. These high-power experimental results are the basis of the beam dynamics iteration and beam testing.
Status update on SUNDAE2 magnetic field test facility at European XFEL
Authors: Baader J E , Abeghyan S , Alanakyan L , Casalbuoni S , La Civita D , Englisch U , Marchetti B , Yakopov G , Yakopov M , Ziolkowski P , Eckoldt H J , Hauberg A , Lederer S , Lilje L , Wohlenberg T , Zimmermann R , Grau A W
Published: January 2024

The implementation and further improvements of superconducting undulators are part of the European XFEL facility development program. Within this program, a magnetic field test facility is being developed. Named SUNDAE2 (Superconducting UNDulAtor Experiment 2), it aims to perform in-vacuum magnetic field measurements of superconducting undulators (SCUs) with three techniques: Hall probe, moving wire, and pulsed wire. This contribution presents the updates and status of SUNDAE2.
A C-band Test Platform for the Development of RF Photo Cathode and High Gradient Accelerating Structures
Authors: Liu X , Li X , Jiang S , Liu S , Xiao Y , Lv Y , Cao X , Lu Z , Liu R , Zhang H , Xie Z , Huang W , Yang R , Yang T , Deng C , Ning C , Yu Y , Wei J , Wang P , Wang Y , Zhao G , Wang L , Xue K , Wu Q
Published: January 2024

In order to promote the studies of low emittance RF photo cathode and high gradient accelerating structures, a C-band test platform has been initialized since late 2021. In this paper, an overview of the present status and future plans of this platform is given. A 3.6-cell C-band RF photo cathode has been manufactured and now is under test. In addition, studies such as the design for a C-band RF traveling-wave accelerating structure and the design of a C-band high gradient parallel-coupled accelerating structure utilizing short pulse are introduced.
Design of an E × B chopper based on permanent magnets
Authors: Jia Duanyang , Wang Zhijun , Xu Zhenyu , Chen Weilong , Chu Yimeng , Su Chunguang
Published: January 2024

Chopper systems are typically used to provide beam time structure and ensure the safety of accelerator operation by deflecting the beam away. The reliability of conventional choppers is entirely based on high-voltage (HV) pulsed power supplies. However, when the power supply fails to charge the electrostatic deflection plate, the beam cannot be cut off, and it will enter the downstream accelerator. To meet the strict beam stopping time requirements of the China Initiative Accelerator Driven System (CiADS), novel E × B chopper design has been developed based on a permanent magnet and an electrostatic deflection plate. This design not only ensures the safety of the accelerator but also provides the necessary pulse waveform. The device is small, highly reliable, and suitable for most accelerators. Moreover, beam dynamics simulations have been conducted to evaluate the chopper’s influence on beam quality, and its beam cutting capability has been analyzed.
Closed-orbit Distortion study of XiPAF upgrading project synchrotron
Authors: Xiong Yang , Yao Hongjuan , Liu Xiaoyu , Wang Zejiang , Li Yan , Zheng Shuxin , Wang Xuewu
Published: January 2024

Xi’an 200 MeV proton application facility (XiPAF) upgrading project is now in the design phase. A six super periods synchrotron is the main component of this project. Using MADX program, a statical analysis of the relationship between closed-orbit distortion (COD) and different types of magnet errors was carried out. Because we do not know the exact error in the design phase, we use rms value to represent errors and CODs. The results show that COD is in direct proportion to magnet error in some cases while the others are square proportional. We regard all the cases as direct proportional since the errors are usually small and find that the error amplification factors differ a lot. These results can give us some meaningful guide in lattice design and magnet error control.
Advanced basic layout of the HElmholtz LInear Accelerator for cw heavy ion beams at GSI
Authors: Barth W , Basten M , Burandt C. , Conrad T. , Dziuba F , Gettmann V , Kürzeder T , Lauber S. , List J. , Miski-Oglu M , Podlech H. , Scheeler U. , Schwarz M , Yaramyshev S
Published: January 2024

The design and construction of continuous wave (cw) high intensity linacs is a crucial goal of worldwide accelerator technology development. The standalone sc heavy ion linac HELIAC (HElmholtz LInear ACcelerator) is a common project of GSI Helmholtz Centre for Heavy Ion Research and Helmholtz Institute Mainz (HIM) under key support of Goethe University Frankfurt (IAP). In 2017 the first section of the linac has been successfully commissioned and extensively tested with beam at GSI, featuring the capability of 216.816 MHz multi-gap Crossbar H-mode (CH) DTL-structures. At present, the first fully equipped cryomodule of the HELIAC is under construction. In addition, six further superconducting CH cavities are being procured. The HELIAC beam dynamics concept foresees a total of twelve CH-cavities in order to accelerate ions with a mass-to-charge ratio of 6 up to an energy of 7.5 MeV/u. In this paper, an advanced very compact and less complex layout is presented, where the same number of accelerating cavities can be accommodated in three instead of four cryomodules, thus also reducing the number of solenoids and rebunchers. In addition, the integration and linking of the HELIAC to the GSI accelerator UNILAC will be outlined.
RF-Acceleration Studies for the HBS-Linac Applying Alternating Phase Focusing Concepts
Authors: Lauber S. , Barth W. , Basten M. , Burandt C. , Droba M. , Dziuba F. , Forck P. , Gettmann V. , Gutberlet T. , Kürzeder T. , List J. , Miski-Oglu M. , Podlech H. , Schwarz M. , Yaramyshev S.
Published: January 2024

The recent layout of the Jülich High Brilliance Neutron Source (HBS) driver linac is based on short crossbar H-mode (CH) cavities operated at a fixed synchronous phase. In the last decades the computing power for the development of linacs, available to physicists and engineers, has been increased drastically. This also enabled the accelerator community to finally carry out the required R&D to generate further the idea of drift tube linacs with alternating phase focusing (APF) beam dynamics, originally proposed in the 1950s. This focusing method uses the electric fields in between the drift tubes (i.e., gaps) to provide subsequent transverse and longitudinal focusing to the beam along multiple gaps. The beam focusing properties within each gap are adjusted individually by means of the synchronous phase. As a result of the alternating phase focusing method, these linacs can operate completely without internal magnetic lenses. The R&D-program for the high brilliance neutron source HBS offered the opportunity to investigate the APF concept further in order to open this advanced concept for high duty-factor, high intensity hadron beam acceleration. Besides, a prototype APF-interdigital H-mode (IH)-cavity has been designed and is going to be build and tested in the next future.
Pre-experiment of 70 MeV H
- cyclotron for producing ISOL RI beam.
Authors: Yeon Y. H. , Heo S. J. , Kim J. W. , Park D. J. , Hwang W. J. , Yim H. J. , Jeong J. W. , Hashimoto T. , Yoo K. H. , Lee J. H.
Published: January 2024

The Rare Isotope Science Project (RISP) is currently constructing equipment and facilities for the Rare Isotope Accelerator complex for ON-line experiments (RAON). The first experiment being conducted involves the acceleration of a proton to 70MeV using a cyclotron, which is then delivered to a SiC target to generate a radioactive isotope beam in the ISOL system. However, before conducting this experiment, a preliminary experiment was performed to confirm the exact location and shape of the proton beam to prevent loss of the proton beam. The pre-experiment involved configuring a faraday cup, wire grid scanner, collimator, and slit inside the proton beam diagnostic module to understand the characteristics of the proton beam at the target position. The beam current ranged from 1 μA to 1.5 μA, and the beam size was confirmed to be within the 2×2cm
2 slit size.
Estimation of the Anode Power Supply Current of the J-PARC MR RF system for 1.36s cycle operation
Authors: Sugiyama Yasuyuki , Tamura Fumihiko , Yoshii Masahito , Ohmori Chihiro , Yamamoto Masanobu , Hara Keigo , Hasegawa Katsushi , Nomura Masahiro , Shimada Taihei , Okita Hidefumi , Miyakoshi Ryosuke
Published: January 2024

The J-PARC Main Ring (MR) delivers high-intensity proton beams for the neutrino experiment. The beam intensity delivered to the neutrino experiment reached 520kW with a cycle time of 2.48 seconds in 2021. We chose to shorten the MR cycle time to 1.36 seconds to achieve higher beam intensity. An anode power supply feeds a high-voltage DC current to the tetrode vacuum tubes, which drive the RF cavity. Beam acceleration in a shorter MR cycle requires a higher RF voltage to keep the RF bucket large enough and a larger anode power supply current for the beam loading compensation. We plan to add RF systems to achieve higher RF voltage and to manage the output current of each anode power supply under limitations. To estimate the anode power supply current with a shorter MR cycle, we derived the beam loading compensation contribution in the power supply current using the data recorded during the operation with a cycle time of 2.48 seconds. We present the estimated anode power supply current for various combinations of RF voltage and the number of RF cavities.
A scheme to extract the beam in advance and transverse beam distribution measurement for the CSNS RCS
Authors: Huang Ming-Yang , Zhu Peng , Xu Shouyan , Li Mingtao , Yuan Yue , Wang Sheng
Published: January 2024

The China Spallation Neutron Source (CSNS) is a large scientific facility for frontier research by using the medium energy protons bombardment of tungsten target to produce a large number of scattered neutrons. The rapid cycling synchrotron (RCS) adopts the single-turn fast extraction scheme to extract the proton beam with the energy of 1.6 GeV, and the extraction repetition frequency is 25 Hz. In order to optimize the painting distribution and reduce the beam loss in the beam commissioning, it is necessary to measure the transverse beam distribution during the injection and acceleration processes. In this paper, a scheme to extract the beam in advance is proposed which is performed by adjusting the extraction timing and extraction mode. By using this extraction mode, the beam can be extracted at different time and the transverse beam distribution can be measured by a multi-wire scanner located on the beam transport line from the RCS to the target. Then, the beam distribution at the desired position on the RCS can be deduced by using the beam transfer matrix.
Multiturn Injection Design and Optimization for XiPAF-Upgrading Synchrotron
Authors: Liu X. Y. , Yao H. J. , Li Y. , Wang Z. J. , Xiong Y. , Zheng S. X. , Wang X. W.
Published: January 2024

XiPAF (Xi’an 200MeV proton application Facility) synchrotron is using H- stripping injection and phase space painting scheme. With the demand of more particle species for single event effect study, XiPAF synchrotron has been upgraded to multiturn injection from stripping injection, the injection system must be redesigned. This paper report XiPAF-Upgrading synchrotron multiturn injection scheme, simulation results by PyORBIT[1] show that the injection efficiency is ∼85% for proton and ∼80% for heavy ions. The influence of space charge and magnet errors on accumulated particle number has been studied by simulation.
Study on XiPAF-Upgrading Synchrotron Beam Loss
Authors: Liu X. Y. , Yao H. J. , Yuan Y. S. , Li Y. , Wang Z. J. , Xiong Y. , Zheng S. X. , Wang X. W.
Published: January 2024

Xi’an 200MeV proton application Facility (XiPAF) is upgrading its proton synchrotron to a multi-ion synchrotron, which replaces H- stripping injection with multiturn injection scheme. New synchrotron’s vertical tune has been changed from 1.70 to 2.26, beam dynamics of new lattice is much different from the original proton lattice. Simulations has been performed with PyORBIT for beam loss study, with or without space charge effect. The main beam loss is caused by 3-order incoherent resonance νx
+ 2νy
= 6, which is a structure resonance. Space charge and longitudinal synchrotron motion speed up the beam loss process.
The impact of the resistive-wall impedance on the ILSF storage ring
Authors: Khosravi N , Dastan S , Akhyani M , Ahmadi E
Published: January 2024

The resistive contribution of the vacuum chamber represents a significant source of the collective effects and should be analysed in several aspects. Due to the NEG-coated re-designed ILSF vacuum chamber, the resistive-wall effects were carefully studied. The measurement setup of the RW test was simulated and compared with the analytical equations. Finally, the longitudinal threshold was presented here to estimate the RW effects on the single bunch instability.
Beam Coupling Impedance Contribution of Flange Aperture Gaps: a Numerical Study for Elettra 2.0
Authors: Cleva S. , Cudin I. , Karantzoulis E. , Rumiz L. , Comisso M. , Passarelli A.
Published: January 2024

The accurate analysis of any possible source of beam instability is mandatory for the design of a new particle accelerator, especially for high-current and ultra-low emittance synchrotrons. In the specific case of instabilities driven by the coupling between the charged particle beam and the electromagnetic field excited by the beam itself, the corresponding effect is estimated through the beam coupling impedance. The modeling of this effect is essential to perform a rigorous evaluation of the coupling impedance budget able to account for all devices present in the entire machine. To deal with this problem, this paper focuses on the estimation of the contribution of the joints lying between the different vacuum chamber sections, by performing a comparative numerical analysis that takes into account different aperture gaps between the flanges. The results point out the criticality of many small-impedance contributions that, added together, must be lower than a predefined impedance threshold.
CSR-induced Projected Emittance Growth Study For The Beam Switchyard At The European XFEL
Authors: Long T. , Chen Y. , Decking W. , Geloni G. , Golubeva N. , Huang S. , Liu S. , Qin W. , Scholz M.
Published: January 2024

Minimizing projected emittance of high brightness electron beam is important for efficient overlap between electron beam and radiation pulse in an FEL facility. Coherent synchrotron radiation (CSR) emission in a single bending section in the beam transport system usually introduces different slice energy modulation hence different slice transverse kicks in the designed dispersion-free lattice, causing projected emittance growth. Here we present theoretical and simulation study of CSR effect on the projected emittance growth in the beam switchyard arc before SASE2 undulator beamline at the European XFEL. We analyze arc optics impact on CSR effect and discuss possible schemes for emittance degradation compensation.
Accelerating Dynamic Aperture Evaluation Using Deep Neural Networks
Authors: Croce D. Di , Giovannozzi M. , Pieloni T. , Seidel M. , Van der Veken F. F.
Published: January 2024

The Dynamic Aperture is an important concept for the study of non-linear beam dynamics in a circular accelerator. The DA is defined as the extent of the phase-space region in which the particle’s motion remains bounded over a finite number of turns. Such a region is shaped by the imperfections in the magnetic fields, beam-beam effects, electron lens, electron clouds, and other non-linear effects. The study of the DA provides insight into the mechanisms driving the time evolution of beam losses, which is essential for the operation of existing circular accelerators, such as the CERN Large Hadron Collider, as well as for the design of future ones. The standard approach to numerical evaluation of the DA relies on the ability to accurately track initial conditions, distributed in phase space, on a realistic time scale, and this is computationally demanding. To accelerate the angular DA calculation, we propose the use of a Machine Learning technique for the angular DA regression based on simulated HL-LHC data. We demonstrate the implementation of a Deep Neural Network model by measuring the time and assessing the performance of the angular DA regressor, as well as carrying out studies with various hardware architectures including CPU, GPU, and TPU.
Initial Application of Machine Learning for Beam Parameter Optimization at the Hefei Light Source II
Authors: Yu Yongbo , Ni Wangbiao , Liu Gongfa , Xu Wei , Li Chuan , Li Weiming , Xuan Ke
Published: January 2024

Machine learning (ML) has become a valuable tool in particle accelerator control, with growing potential for beam parameter correction. In this study, we present preliminary ML applications at HLS-II, using Lasso regression for online tune correction and a neural network (NN) for beta function simulation correction. Both models were trained with supervised learning on measured beam parameter data, while an improved genetic algorithm optimized the NN structure. Our results show that the ML-based approach achieves competitive correction quality with fewer steps, making it a promising method for future particle accelerator applications and other fields.
Beam Profile Measurement Using the Highly-Oriented Pyrolytic Graphite
Authors: Kitamura R , Hayashi N , Hirano K , Kosaka S , Miyao T , Morishita T , Nemoto Y
Published: January 2024

The mitigation of heat loading is one of the important issues for beam instrumentation to measure the high-power proton beam. Recently, the highly-oriented pyrolytic graphite (HOPG) material was used for the target probe of the bunch-shape monitor at the front end in the Japan Proton Accelerator Research Complex (J-PARC). Since the thermal conductivity of the HOPG is high, it is suitable to measure both transverse and longitudinal beam profiles under the condition of high heat loading. As an application of the HOPG, for example, the thin HOPG may be used as a substitutive material of the target wire for the transverse profile monitor such as the wire scanner monitor. The possibility of the HOPG target for both transverse and longitudinal beam profile monitors is discussed from some results of the test experiment using the 3 MeV negative hydrogen ion beam at the test stand.
TLS Fast Orbit Feedback Upgrade
Authors: Chiu P. C. , Huang C. H. , Wu C. Y. , Hsu K. T. , Chen Jenny , Lee Demi , Cheng Y. S. , Liao C. Y. , Hu K. H.
Published: January 2024

The Orbit Feedback System (OFB) at the Taiwan Light Source (TLS) was implemented two decades ago and has undergone multiple upgrades to enhance its performance. The loop bandwidth was constrained by the available hardware. The system is unable to eliminate perturbations from a fast source. In order to enhance the performance of orbit feedback, the system underwent an upgrade in 2008. The upgrade involved the replacement of the analog-type BPM electronics with digital BPM electronics, as well as the replacement of the corrector power supply with a high-performance switching-type power supply that has a wide bandwidth. Following the commissioning of the Taiwan Photon Source (TPS) in 2015, a decision was made to gradually migrate the control system of the Taiwan Light Source to the Experimental Physics and Industrial Control System (EPICS). This decision was made in order to facilitate resource sharing between the two facilities since EPICS had already been adopted by TPS. The Orbit Feedback System is a revitalized subsystem that now benefits from EPICS support. Additionally, the feedback computation unit has been upgraded to a Field Programmable Gate Array (FPGA), resulting in an increase in the calculating cycle from 2.5 kHz to 10 kHz. This report presents a concise overview of the integration of fast orbit feedback and the outcomes of the orbit stability enhancement following the upgrade.
Development of new synchronized data system for J-PARC RCS
Authors: Takahashi H , Saha P K , Yoshimoto M , Sawabe Y
Published: January 2024

In J-PARC 3 GeV Rapid Cycling Synchrotron, the synchronized data system with reflective memory was constructed. However, this system has been operated for more than 10 years, it is essential to take countermeasures against deterioration over time. In addition, this system is difficult to support the large data sizes that have been recently requested. Therefore, we proposed a new synchronized data generation method. The test bench for a new synchronized data system that implements the new method was configured and its performance was verified. This result leads to the development of a new synchronous data system based on data transfer via LAN. In this paper, we describe the outline of the new synchronized data generation method and the results of performance tests.
FAIR SIS100 accelerating RF system - Modeling and analysis of the coupled LLRF control loops
Authors: Wegmann C J , Kronshorst L , Orth S , Groß K , Klingbeil H , Lens D E M , Schmidt J S , Stuhl A , Zipfel B
Published: January 2024

The SIS100 heavy ion synchrotron as core part of the Facility for Antiproton and Ion Research (FAIR) will be equipped with 14 accelerating RF stations in the first stage of realization. Each RF station consists of a tunable ferrite-loaded cavity powered by a tetrode amplifier. Further key components are a solid-state pre-amplifier, a power supply unit, and dedicated Low-Level Radio Frequency (LLRF) feedforward and feedback systems to control amplitude and phase of the cavity gap voltage as well as the resonance frequency. Each cavity has to provide up to 20 kV peak gap voltage in the frequency range from 1.1 to 3.2 MHz. While all components of the system have been successfully tested in the factory acceptance tests and transferred to the FAIR storage, the First-of-Series (FoS) RF station is still persistently operated at GSI to gain experience. For further insight into the LLRF part, especially the stability of the control loops, the inter-coupling of the three local control loops was analyzed with methods from control theory based on simplified but realistic models, which have been developed based on extensive measurements and analysis of the systems’ behavior. In this contribution, the modeling as well as the analysis of the coupling between the LLRF control loops are discussed and the results are presented in comparison with measurements on the FoS system.