bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generation of two terahertz radiation pulses with continuously tunable frequency and time delay
Authors: Wang Wenxing , Zhang Haoran , Jiang Shimin , He Zhigang 
Published: December 2019

Abstract
We propose to generate two narrow band terahertz pulses radiated from two temporally modulated relativistic electron beams, which are generated in a photo-injector. The temporal profile of the drive laser is modulated by means of the paired chirped pulses beating technique, leading to the generation of two pre-bunched electron beams. Coherent transient radiation (CTR) is considered as the mechanism for terahertz radiation generation. The frequencies of the two terahertz pulses can be independently tuned by adjusting the paired beating frequencies, and the interval between the two terahertz pulses can be adjusted by the optical delay line.
Comparison of constrained optimization methods for designing a multi-bend achromat lattice
Authors: Xu J H , Bai Z H , Yang P H , Li W M 
Published: December 2019

Abstract
In the design of a multi-bend achromat (MBA) lattice for a diffraction-limited storage ring, there are usually many magnet parameters to be optimized and some stringent constraints to be satisfied. For example, to cancel out nonlinear dynamics effects, the phase advances between some sections are generally required to be set to certain values in the lattice design. For better designing a MBA lattice using an evolutionary algorithm, the handling of constraints will be important, because it is very hard to satisfy the constraints for most or even all of solutions in the early generations of the algorithm. This paper will first describe some methods for handling constraints, which are then applied to designing a hybrid 7BA lattice. The comparison of these methods shows that better lattice solutions can be obtained by including constraints into objective functions.
Design studies of a proof-of-principle experiment on THz SASE FEL at PITZ
Authors: Li X.-K. , Krasilnikov M. , Boonpornprasert P. , Shaker H. , Chen Y. , Good J. , Gross M. , Huck H. , Isaev I. , Koschitzki C. , Lal S. , Lishilin O. , Loisch G. , Melkumyan D. , Niemczyk R. , Oppelt A. , Qian H. , Shu G. , Stephan F. , Vashchenko G. 
Published: December 2019

Abstract
A free-electron laser based THz source is undergoing design studies at the Photo Injector Test facility at DESY in Zeuthen (PITZ). It is considered as a prototype for pump-probe experiments at the European XFEL, benefiting from the fact that the electron beam from the PITZ facility has an identical pulse train structure as the XFEL pulses. In the proposed proof-of-principle experiment, the electron beam (up to 4 nC bunch charge and 200 A peak current) will be accelerated to 16-22 MeV/c to generate SASE radiations in an LCLS-I undulator in the THz range between 60 and 100 pm with an expected energy of up to ~1 mJ/pulse. In this paper, we report our simulations on the optimization of the photo-injector and the design of the transport and matching beamline. Experimental investigations on the generation, characterization and matching of the high charge beam in the existing 22-m-long beamline will also be presented.
Improvement of 6D brightness by a 1.4-cell photocathode RF gun for MeV Ultrafast electron diffraction
Authors: Song Y , Yang J , Tsai C , Fan K 
Published: December 2019

Abstract
Recent research indicates that ultrafast electron diffraction and microscopy (UED/M) have unprecedented potential in probing ultrafast dynamic processes, especially in organic and biological materials. However, reaching the required brightness while maintaining high spatiotemporal resolution requires new design of electron source. In order to produce ultrashort electron beam with extreme high brightness, a 1.4-cell RF gun is being developed to reach higher acceleration gradient near the photocathode and thus suppress the space charge effect in the low energy region. Simulation of the 1.4-cell RF photocathode gun shows considerable improvement in bunch length, emittance and energy spread, which all lead to better temporal and spatial resolution comparing to traditional 1.6-cell RF photocathode gun. The results demonstrate the feasibility of sub-ps temporal resolution with normalized emittance less than 0.1 πmm·mrad while maintaining 1 pC electron pulse.
Suppression of Microbunching Instability Through Dispersive Lattice
Authors: Li Biaobin , Qiang Ji 
Published: December 2019

Abstract
The microbunching instability from the initial small modulation such as shot-noise can be amplified by longitudinal space-charge force and causes significant electron beam quality degradation at the exit of accelerator for the next generation x-ray free electron laser. In the paper, we present analytical and numerical simulation studies of a novel method using dispersion leakage from a quadrupole inside a bunch compressor chicane.
Design and analysis of the cold cathode ion source for 200 MeV superconducting cyclotron
Authors: Xu S.W. , Chen G. , Xu M.M. , Karamyshev O. , Karamyshev G. , Shirkov G. , Calabretta L. 
Published: December 2019

Abstract
SC200 is a superconducting isochronous cyclotron which generates 200 MeV, 400 nA proton beam for particle therapy. The cold-cathode-type Penning ion gauge (PIG) ion source for the internal ion source of SC200 has been selected as an alternative and preliminary designed. In this paper, design of ion source and test bench are demonstrated. Currently, the properties of ion source have been simulated for a variety of electric field and magnetic field distributions. The secondary electron emission in electromagnetic field has been simulated. It provides reference for the optimization design of arc chamber. In addition, the sample of cold-cathode-type ion source has been tested on the test bench and extracted beam intensity has been measured over 200 μA.
Eupraxia, A Step Toward A Plasma-Wakefield Based Accelerator With High Beam Quality
Authors: Nghiem P A P , Alesini D , Aschikhin A , Assmann R W , Audet T , Beck A , Chance A , Chen M , Chiadroni E , Cianchi A , Clarke J A , Couprie M E , Croia M , Cros B , Dattoli G , Del Dotto A , Delerue N , Dorda U , Ferran Pousa A , Ferrario M , Fonseca R A , Ghaith A , Giribono A , Gizzi L A , Helm A , Hidding B , Hooker S M , Ibison M G , Jaroszynski D A , Kruchinin K O , Labate L , Lee P , Li X , Li F Y , Libov V , Marchetti B , Martinez de la Ossa A , Marx D , Massimo F , Mathieu F , Maynard G , Mazzotta Z , Mehrling T J , Molodozhentsev A Y , Mosnier A , Mostacci A , Najmudin Z , Nguyen F , Niknejadi P , Oumbarek Espinos D , Pattathil R , Pompili R , Romeo S , Rossi A R , Schaper L , Sheng Z M , Shpakov V , Silva L O , Silva T , Simon C , Specka A , Stella A , Streeter M J V , Svystun E N , Symes D , Terzani D , Toci G , Tomassini P , Vaccarezza C , Vieira J M , Vujanovic M , Walczak R , Walker P A , Weikum M K , Welsch C P , Weng S M , Wiggins S M , Wolfenden J , Yoffe S , Zhu J 
Published: December 2019

Abstract
The EuPRAXIA project aims at designing the world's first accelerator based on advanced plasma-wakefield techniques to deliver 5 GeV electron beams that simultaneously have high charge, low emittance and low energy spread, which are required for applications by future user communities. Meeting this challenging objective will only be possible through dedicated effort. Many injection/acceleration schemes and techniques have been explored by means of thorough simulations in more than ten European research institutes. This enables selection of the most appropriate methods for solving each particular problem. The specific challenge of generating, extracting and transporting high charge beams, while maintaining the high quality needed for user applications, are being tackled using innovative approaches. This article highlights preliminary results obtained by the EuPRAXIA collaboration, which also exhibit the required laser and plasma parameters.
Hardware Commissioning of the Renovated PIAVE Injector at INFN-LNL
Authors: Bortolato D , Andreev V , Bellan L , Bellato M A , Bermudez J Y , Bisoffi G , Bissiato E , Chiurlotto F , Comunian M , Contran T , Facco A , Fagotti E , Francescon P , Friso A , Galatà A , Gallo C S , Giacchini M G , Lollo M , Martini D , Miglioranza M O , Modanese P , Montis M , Munaron E , Nigrelli G , Pavinato S , Pengo M , Pisent A , Poggi M , Pranovi L , Rossignoli M , Scarpa D 
Published: December 2019

Abstract
During 2018, the PIAVE superconducting linac injector at INFN-LNL, based on superconducting RFQs and two cryomodules with quarter wave resonators, underwent a renovation plan. This operation was strictly related to the one carried out on ALPI [1], which will become a post-accelerator for both stable and exotic beams in a near future. PIAVE Quarter Wave Resonator (QWR) cryomodules, in operation since 2006, were moved to ALPI to be used for the acceleration of both stable beams and future exotic beams delivered from the cyclotron target-ion-source station, after appropriate purification, charge breeding and pre-acceleration stages. In order to cope with the removal of the two QWR cryomodules in PIAVE, a newly designed 80 MHz room temperature buncher was designed, built and tested: the buncher is required so as to match the longitudinal phase space between PIAVE superconducting RFQs (SRFQ1 and SRFQ2) and ALPI. In the same period, substantial refurbishments on the ECR ion source platform were carried out, in particular on its infrastructure and safety equipment. A problem on an electronic component on SRFQ2, though quickly fixed, delayed beam commissioning of the PIAVE injector, which will start at the end of May 2019.
Design and low power test of Preparing a prototype HOM linac1
Authors: Lu Ling , Xing Chaochao , He Tao , Yang Lei , Xu Xianbo , Li Jia , Xia Qianxu , Gao Zhichao 
Published: December 2019

Abstract
Normally, drift tube linacs (DTLs) are used following RFQ linacs for beam acceleration in middle and high energy region. The acceleration efficiency of DTLs is decreasing with beam energy increasing. Using resonated higher order mode (HOM) of cavity, DTLs can achieve a higher effective shunt impedance. We proposed a 325 MHz DTL with TE115 mode and finished the 1st HOM-DTL assembly. In this paper, the designs and results of low power test of the 1st HOM-DTL will be reported.
Mechanical robustness of HL-LHC collimator designs
Authors: Carra F , Bertarelli A , Gobbi G , Guardia-Valenzuela J , Guinchard M , Harden F , Pasquali M , Redaelli S , Skordis E 
Published: December 2019

Abstract
Two new absorbing materials were developed as collimator inserts to fulfil the requirements of HL-LHC higher brightness beams: molybdenum-carbide graphite (MoGr) and copper-diamond (CuCD). These materials were tested under intense beam impacts at CERN HiRadMat facility in 2015, when full jaw prototypes were irradiated. Additional tests in HiRadMat were performed in 2017 on another series of material samples, including also improved grades of MoGr and CuCD, and different coating solutions. This paper summarizes the main results of the two experiments, with a main focus on the behaviour of the novel composite blocks, the metallic housing, as well as the cooling circuit. The experimental campaign confirmed the final choice for the materials and the design solutions for HL-LHC collimators, and constituted a unique chance of benchmarking numerical models. In particular, the tests validated the selection of MoGr for primary and secondary collimators, and CuCD as a valid solution for robust tertiary collimators.
The K12 beamline for the KLEVER experiment
Authors: van Dijk M W U , Banerjee D , Bernhard J , Brugger M , Charitonidis N , D’Alessandro G L , Doble N , Gatignon L , Gerbershagen A , Montbarbon E , Moulson M , Rae B , Rosenthal M , Veit B M 
Published: December 2019

Abstract
The KLEVER experiment is proposed to run in the CERN ECN3 underground cavern from 2026 onward. The goal of the experiment is to measure

BR
(

K
L

→

π
0

v

v
¯

)

, which could yield information about potential new physics, by itself and in combination with the measurement of

BR
(

K
+

→

π
+

v

v
¯

)

of NA62. A full description will be given of the considerations in designing the new K12 beamline for KLEVER, as obtained from a purpose made simulation with FLUKA. The high intensities required by KLEVER, 2 × 1013 protons on target every 16.8 s, with 5 × 1019 protons accumulated over 5 years, place stringent demands on adequate muon sweeping to minimize backgrounds in the detector. The target and primary dump need to be able to survive these demanding conditions, while respecting strict radiation protection criteria. A series of design choices will be shown to lead to a neutral beamline sufficiently capable of suppressing relevant backgrounds, such as photons generated by π
0 decays in the target, and Λ → nπ
0 decays, which mimic the signal decay.
Disk and Washer Coupled Cavity Linac Design and Cold-Model for Muon Linac
Authors: Otani M. , Futatsukawa K. , Mibe T. , Naito F. , Hasegawa K. , Ito T. , Kitamura R. , Kondo Y. , Morishita T. , Iinuma H. , Nakazawa Y. , Iwashita Y. , Saito N. 
Published: December 2019

Abstract
A disk and washer (DAW) coupled cavity linac (CCL) was developed for a mediumvelocity part in a muon linac to measure muon anomalous magentic moment and search for electric dipole moment. Muons were accelerated from v/c = β = 0.3 to 0.7 at an operational frequency of 1.3 GHz. In this paper, the cavity design, beam dynamics design, and cold-model measurements are presented.
Beam Line Optimization using Derivative-Free Algorithms
Authors: Appel S. , Reimann S. 
Published: December 2019

Abstract
The present study focuses on the beam line optimization from the heavy-ion synchrotron SIS18 to the HADES experiment. BOBYQA (Bound Optimization BY Quadratic Approximation) solves bound constrained optimization problems without using derivatives of the objective function. The Bayesian optimization is another strategy for global optimization of costly, noisy functions without using derivatives. A python programming interface to MADX allow the use of the python implementation of BOBYQA and Bayesian method. This gave the possibility to use tracking simulation with MADX to determine the loss budget for each lattice setting during the optimization and compare both optimization methods.
Beam loss and the stripping efficiency measurement for CSNS injection system
Authors: Huang Ming-Yang , Wang Sheng , Xu Shou-Yan 
Published: December 2019

Abstract
The injection beam loss is the main beam loss of the rapid cycling synchrotron (RCS) for the China Spallation Neutron Source (CSNS). After the optimization of injection system during the beam commissioning, the current injection beam loss for CSNS/RCS is approximately 1%. There are several sources of injection beam loss. In order to distinguish these different sources, the stripping efficiency of the main stripping foil should be studied and measured accurately. In this paper, a scheme for the accurate measurement of the stripping efficiency for CSNS will be proposed and studied. It can not only reduce the injection beam loss, but also be used to estimate the operation state and lifespan of the main stripping foil accurately. This method will be applied in future beam commissioning.
Power losses caused by longitudinal HOMs in 3.9 GHz SHINE cryomodule
Authors: Guo Junjie , Gu Qiang , Tan Jianhao , Wang Zhen 
Published: December 2019

Abstract
Shanghai high repetition-rate XFEL and extreme light facility (SHINE), the first hard XFEL based on a superconducting accelerated structure in China, is now under development at the Shanghai Institute of Applied Physics, Chinese Academy of Sciences. In this paper, power losses caused by trapped longitudinal high order modes (HOM) and steady-state loss generated by untrapped HOMs in 3.9 GHz SHINE cryomodule will be investigated and calculated. Results are presented for power losses of every element in 3.9 GHz cryomodule, caused by HOM excitation in the acceleration RF system of the continues-wave (CW) linac of SHINE.
Model predictive power distribution in an electric vehicle with a fuel cell
Authors: Scherler Soeren , Liu-Henke Xiaobo 
Published: December 2019

Abstract
Within the subproject “Intelligent Electric Vehicles with Range Extender in Traffic Systems with Vehicle 4.0” (iREX 4.0), which is part of the joint project “Future Vehicle Technologies in the Open Region Lab” (“Zukünftige Fahrzeugtechnologien im Open Region Lab“, ZuFOR), funded by the Ministry of Science and Culture of Lower Saxony and the Volkswagen Foundation, the research work focuses on cross-linked autonomous electric vehicles with fuel cells serving as range extenders. The aim of the project is the conception of digitized traffic systems that consist of cross-linked autonomous electric vehicles with range extender (RE). This contribution presents an approach for a model predictive power distribution to the energy sources battery and fuel cell considering their specific characteristics.
Peg-in-a-hole by haptic teleoperation
Authors: Argin Omer Faruk , Bayraktaroglu Zeki Yagiz 
Published: December 2019

Abstract
This paper presents the experimental study on the application of the peg-in-a-hole task in the proposed haptic teleoperation system. Motion references from the user towards the remote manipulator and force feedback signals from the remote environment towards the user are transmitted through a virtual reality layer where the remote operation is simulated in real-tme. Various physical interactions occuring in the bilatral loop are modelled and controlled through the introduction of virtual spring-damper elements. Modeling and controller design of the teleoperation system is made modular and straightforward with the use of identical virtual dynamics. The design approach combines the introduction of the middle layer of virtual reality and modeling of all interactons by identical virtual spring-dampers. The haptic teleoperation system is experimentally evaluated with experienced and unexperienced users in the bilateral loop. Experimental results show that stable peg-in-a-hole operation is achieved in presence of bounded time-delays in all communication channels between the user, virtual reality layer and remote environment. Improvements of the teleoperation performances in terms of position tracking and total operation time are also observed in experiments.
The Immediate Consequences of Federal Pretrial Detention
Authors: Didwania Stephanie Holmes 
Published: December 2019

Abstract
Unlike the cash-bail regimes that are prevalent in state courts, federal courts rarely use money bail as a condition of pretrial release. Nonetheless, this article presents evidence that pretrial release influences case outcomes for federal defendants. Using case data spanning 71 federal district courts, the article suggests that pretrial release reduces a defendant’s sentence and increases the probability that they will receive a sentence below the recommended sentencing range. Pretrial release also appears to lessen the probability that a defendant will receive a mandatory minimum sentence when one is charged. The analysis exploits variation in magistrate judges’ propensities to release defendants pending trial, which allows magistrate judge leniency to serve as an instrumental variable for pretrial release. The article also provides suggestive evidence that pretrial release affects case outcomes through two channels: first, by giving defendants the opportunity to present mitigating evidence at sentencing and second, by making it easier for defendants to earn a sentencing reduction by providing assistance to the government.
Inequality and majority rule
Authors: Bruner Justin P 
Published: December 2019

AbstractI provide a novel argument in favour of majority rule. In particular, I consider the distribution of voter satisfaction in response to the outcome of a vote and prove that under certain conditions majority rule minimizes the level of inequality present in the distribution of voter satisfaction. This finding is reinforced by a computer simulation as well as an analysis of over four decades of polling data. Results complement existing procedural justifications of majority rule, demonstrating that majority rule ensures equality at the level of both procedure and outcome.
Semantic persistence of ambiguous biomedical names in the citation network
Authors: Rodriguez-Esteban Raul 
Published: December 2019

Abstract

Motivation
Name ambiguity has long been a central problem in biomedical text mining. To tackle it, it has been usually assumed that names present only one meaning within a given text. It is not known whether this assumption applies beyond the scope of single documents.

Results
Using a new method that leverages large numbers of biomedical annotations and normalized citations, this study shows that ambiguous biomedical names mentioned in scientific articles tend to present the same meaning in articles that cite them or that they cite, and, to a lesser extent, two steps away in the citation network. Citations, therefore, can be regarded as semantic connections between articles and the citation network should be considered for tasks such as automatic name disambiguation, entity linking and biomedical database annotation. A simple experiment shows the applicability of these findings to name disambiguation.

Availability and implementation
The code used for this analysis is available at: https://github.com/raroes/one-sense-per-citation-network.
SSIPe: accurately estimating protein–protein binding affinity change upon mutations using evolutionary profiles in combination with an optimized physical energy function
Authors: Huang Xiaoqiang , Zheng Wei , Pearce Robin , Zhang Yang 
Published: December 2019

Abstract

Motivation
Most proteins perform their biological functions through interactions with other proteins in cells. Amino acid mutations, especially those occurring at protein interfaces, can change the stability of protein–protein interactions (PPIs) and impact their functions, which may cause various human diseases. Quantitative estimation of the binding affinity changes (ΔΔGbind) caused by mutations can provide critical information for protein function annotation and genetic disease diagnoses.

Results
We present SSIPe, which combines protein interface profiles, collected from structural and sequence homology searches, with a physics-based energy function for accurate ΔΔGbind estimation. To offset the statistical limits of the PPI structure and sequence databases, amino acid-specific pseudocounts were introduced to enhance the profile accuracy. SSIPe was evaluated on large-scale experimental data containing 2204 mutations from 177 proteins, where training and test datasets were stringently separated with the sequence identity between proteins from the two datasets below 30%. The Pearson correlation coefficient between estimated and experimental ΔΔGbind was 0.61 with a root-mean-square-error of 1.93 kcal/mol, which was significantly better than the other methods. Detailed data analyses revealed that the major advantage of SSIPe over other traditional approaches lies in the novel combination of the physical energy function with the new knowledge-based interface profile. SSIPe also considerably outperformed a former profile-based method (BindProfX) due to the newly introduced sequence profiles and optimized pseudocount technique that allows for consideration of amino acid-specific prior mutation probabilities.

Availability and implementation
Web-server/standalone program, source code and datasets are freely available at https://zhanglab.ccmb.med.umich.edu/SSIPe and https://github.com/tommyhuangthu/SSIPe.

Supplementary information
Supplementary data are available at Bioinformatics online.