bluuebunny/crossref_metadata_2025 huggingface dataset:
Do Prescription Drug Monitoring Programs Encourage Prescription – or Illicit – Opioid Abuse?
Authors: Meadowcroft Devon , Whitacre Brian
Published: December 2019

Background

Prescription drug monitoring programs (PDMPs) are tools that states can use to fight prescription opioid misuse within their jurisdiction. However, because PDMPs make prescription opioids more difficult to access, these programs may have the unintended consequence of increasing deaths related to illicit opioids.

Methods

This study uses fixed effects models to estimate how PDMP regulatory strength is associated with both prescription opioid- and heroin-related deaths between 1999 and 2016. PDMP regulatory strength is measured by creating a score using multiple correspondence analysis (MCA). Additional models replace the MCA score with a binary indicator for the presence of one particular regulation requiring physicians to access the system before writing opioid prescriptions.

Results

Results show that continuous measures of PDMP strength are not generally associated with prescription opioid- or heroin-related death rates. Yet, one model does show that PDMP scores are positively associated with the heroin-related death rate. The models using the binary mandatory access variable show a strong positive association with both prescription opioid and heroin deaths.

Conclusions

This study supports the theory that more stringent state PDMPs are associated with higher rates of heroin-related deaths, potentially due to decreases in prescription opioid availability.
Suppression of ILC2 differentiation from committed T cell precursors by E protein transcription factors
Authors: Qian Liangyue , Bajana Sandra , Georgescu Constantin , Peng Vincent , Wang Hong-Cheng , Adrianto Indra , Colonna Marco , Alberola-Ila Jose , Wren Jonathan D. , Sun Xiao-Hong
Published: December 2019

Current models propose that group 2 innate lymphoid cells (ILC2s) are generated in the bone marrow. Here, we demonstrate that subsets of these cells can differentiate from multipotent progenitors and committed T cell precursors in the thymus, both in vivo and in vitro. These thymic ILC2s exit the thymus, circulate in the blood, and home to peripheral tissues. Ablation of E protein transcription factors greatly promotes the ILC fate while impairing B and T cell development. Consistently, a transcriptional network centered on the ZBTB16 transcription factor and IL-4 signaling pathway is highly up-regulated due to E protein deficiency. Our results show that ILC2 can still arise from what are normally considered to be committed T cell precursors, and that this alternative cell fate is restrained by high levels of E protein activity in these cells. Thymus-derived lung ILC2s of E protein–deficient mice show different transcriptomes, proliferative properties, and cytokine responses from wild-type counterparts, suggesting potentially distinct functions.
It’s time to look more closely at RYR3
Authors: Sedwick Caitlin
Published: December 2019

JGP study shows that ryanodine receptor 3 is important for extraocular muscle function.
A Cross-Cell Interleaved Nonlinear Lattice for Potential NSLS-II Upgrade
Authors: Li Yongjun , He An , Shaftan Timur , Smaluk Victor , Kosciuk Bernard , Bai Zhenghe , Wang Lin
Published: December 2019

An interleaved sextupole scheme using a cross-cell betatron phase cancellation technique is adopted as a candidate for a future upgrade to the NSLS-II lattice. The upgraded lattice will use as many NSLS-II installed magnets as possible, including 30 dipoles, which will create a triple bend achromat configuration. A 300 pm-rad horizontal beam emittance has already been achieved with the current configuration. The emittance can be further reduced to around 200 pm-rad with damping wigglers. Some new design concepts used in modern 4th-generation light sources, such as adopting longitudinal gradient bends and reverse bends, are incorporated into the design as well. The betatron phase-advance between sextupoles is designed to have a cross-cell interleaved cancellation pattern in the transverse planes. The dynamic aperture is sufficient to allow the conventional off-axis top-off injection. At the same time, a large energy acceptance looks promising and would ensure a sufficiently long beam lifetime.
A General Comparison On Impedance Theory And Cst Simulation of Discontinuities
Authors: Khosravi N. , Akhyani M. , Ahmadi E. , Mashal A. , Karimi H. , Dastan S.
Published: December 2019

Inhomogeneity of vacuum chamber components is the main source of coupling impedance. Nowadays, wake impedances are mostly predictable by 3D codes and analytical prediction of impedance theories can be helpful as a side solution. On the other hand, some asymmetries in the geometry of components might make troubles and lead to imprecise numerical results in 3D simulations. Analytical approximation of discontinuities, holes and grooves can give us an estimation of expected results and can be used as a benchmark in the case that we do not have any experimental data.

To clarify the validity of theoretical expressions, general discontinuities are simulated in CST Particle Studio. The comparison of final results is presented here. At last, Resistive Wall impedance and some general discontinuities of components at ILSF storage ring are compared form the theoretical and simulation point of view.
Synchrotron Radiation Reflections in the CLIC Beam Delivery System
Authors: Arominski D. , Latina A. , Sailer A. , Schulte D.
Published: December 2019

Synchrotron radiation (SR) reflction is an important issue for future linear colliders. High fluxes of SR might impact the performance of the detector, through irradiation of the forward luminosity and beam quality calorimeters or of the innermost layers of the vertex detector. The photon reflections depend on the beam pipe apertures' size, their shape, and materials used with various surface roughness. In this work, we present a study of SR including reflection for the 380GeV and 3 TeV beam parameters and optics of the Compact Linear Collider's Final Focus System. The simulations of the SR reections using the Synrad+ software are presented and the impact on the detector is discussed.
Coherent vs incoherent effects and Debye length
Authors: Franchetti Giuliano
Published: December 2019

For some class of studies, the space charge is treated as frozen, allowing to capture the dynamics of incoherent phenomena. We explore the possibility that a beam may exhibit non-resonant coherent behavior by developing and studying a one-dimensional model.
SixTrack Version 5: Status and New Developments
Authors: De Maria R. , Andersson J. , Berglyd Olsen V.K. , Field L. , Giovannozzi M. , Hermes P.D. , Høimyr N. , Iadarola G. , Kostoglou S. , Maclean E.H. , McIntosh E. , Mereghetti A. , Molson J. , Pellegrini D. , Persson T. , Schwinzerl M. , Dalena B. , Pugnat T. , Zacharov I. , Sjobak K.N.
Published: December 2019

SixTrack Version 5 is a major SixTrack release that introduces new features, with improved integration of the existing ones, and extensive code restructuring. New features include dynamic-memory management, scattering-routine integration, a new initial-condition module, and reviewed post-processing methods. Existing features like on-line aperture checking and Fluka-coupling are now enabled by default. Extensive performance regression tests have been developed and deployed as part of the new-release generation. The new features of the tracking environment developed for the massive numerical simulations will be discussed as well.
Frequency Map Measurements at the TPS
Authors: Chen C H , Chiu M S , Chen J Y , Tseng F H , Chen B Y , Huang B Y , Hsu T W , Lin W Y , Kuo C C , Tsai H J , Liu Y C , Chou P J
Published: December 2019

The Taiwan Photon Source (TPS) has been operated now for several years since its successful commissioning in December 2014 and has achieved reliable routine operation up to 500 mA with more than 10 hrs beam lifetime. Dynamic aperture (DA) measurements and associated frequency map analyses (FMA) at the TPS reveal beam dynamics behavior with and without insertion devices. A preliminary study based on turn-by-turn beam position monitor (BPMs) is presented in this paper.
An analytic approach to emittance growth from the beam- beam effect with applications to the LHeC
Authors: Nissen E , Schulte D
Published: December 2019

In colliders with asymmetric rigidity such as the proposed Large Hadron electron Collider, jitter in the weaker beam can cause emittance growth via coherent beam-beam interactions. The LHeC in this case would collide 7 TeV protons on 60 GeV electrons, which can be modeled using a weak-strong model. In this work we estimate the proton beam emittance growth by separating out the longitudinal angular kicks from an off-center bunch interaction and produce an analytic expression for the emittance growth per turn in systems like the LHeC.
Improving high precision cam mover’s stiffness
Authors: Kemppinen J , Mainaud Durand H , Herty A
Published: December 2019

Pre-alignment is a key challenge of the Compact Linear Collider (CLIC) study. The requirement for CLIC main beam quadrupole (MBQ) alignment is positioning to within 1 μm from target in 5 degrees of freedom (DOF) with ± 3mm travel. After motion, the position should be kept passively while the system's fundamental frequency is above 100Hz. Cam movers are considered for the task. Traditionally they are used for the alignment of heavier magnets with lower accuracy and stiffness requirement. This paper presents a new CLIC prototype cam mover with design emphasis on the fundamental frequency. A finite element method (FEM) model predicts the mode shapes and eigenfrequencies of the system and can be used for further improving the design. Experimental modal analysis (EMA) of the prototype shows that the prototype's fundamental frequency is at 44Hz. It also validates the FEM model.
Collimation of target induced halo following MAGIX at MESA
Authors: Ledroit B , Aulenbacher K
Published: December 2019

The Mainz Energy-recovering Superconducting Accelerator (MESA) will be an electron accelerator allowing operation in energy-recovery linac (ERL) mode. It provides the opportunity to operate scattering experiments at energies of ~ 100 MeV with thin gas-targets. The MESA Internal Gas Target Experiment (MAGIX) aims to operate windowless jet targets and different gases up to Xenon to search for possible dark photon interactions, to precisely measure the magnetic proton radius and astrophysical S-factors. Investigations on the impact of the target on beam dynamics and beam losses are required for machine safety and to examine limits to ERL operation. The goal of this work is to understand target induced halo in the different experimental setups, track halo particles through downstream sections to examine beam losses and include a suitable collimation system and shielding into the accelerator layout to protect the machine from direct and indirect damage through beam losses and radiation. The present status of the investigations is presented.
Energy measurement and correction for stable operation in J-PARC
Authors: Moriya K , Harada H , Liu Y , Otani M
Published: December 2019

In Japan Proton Accelerator Research Complex (J-PARC), the beam accelerated up to 400MeV in the Linac is injected to 3 GeV rapid cycling synchrotron (RCS), and we realize the high intensity beam by using multi-turn injection. During a user operation, we rarely detected the beam loss at the high dispersion area in the RCS or the beam collimator section in the extraction beam transport line. These incidents indicate that the beam loss is caused by the momentum shift of RCS injection beam according to the experimental and simulated data. In the beam commissioning, we check the Linac beam momentum just before a user operation of the RCS. However, we could not previously measure the Linac beam momentum during the user operation because we adopt the multi-turn injection with synchrotron oscillation for longitudinal plane. Therefore, we measured the beam momentum in the beam injection line of the RCS. Because the Linac-to-3-GeV-RCS Beam Transport line (L3BT) has the high dispersion areas, we estimated the RCS-injection momentum from the beam orbit data by the Beam Position Monitors (BPMs). We measured the beam position data by these BPMs, and estimated the momentum shift by using the data and beam simulation. As a result, we found the momentum fluctuation during the user operation, and the fluctuation ∆p/p was shifted up to 0.1% from the reference. In addition, to suppress this beam loss induced by the momentum fluctuation and shift, we developed the momentum correction system. The fluctuation was achieved less than ±0.02 % with this system. Finally, the beam loss incidents induced by the beam momentum shift does not occur, and we successfully achieved the more stable user operation in J-PARC.
Reduction of beam induced RF-heating in the horizontal stripline kicker at the TPS
Authors: Chou P J , Chan C K , Chang C C , Hsu K T , Hu K H , Kuan C K , Sheng I C
Published: December 2019

In preparation for 500 mA operation at the Taiwan Photon Source (TPS), we redesigned the horizontal stripline kicker for the beam feedback system to gain a smaller loss factor with higher shunt impedance. We introduced ground fenders (see figure 1) to this new design which resulted in the reduction of the loss factor and substantial increase of the kicker shunt impedance. The transverse profile of the kicker electrodes was matched to the racetrack beam pipe in the straight sections to minimize broadband impedance. The ground fenders can reduce the leakage of image currents through the gaps between the two strip line electrodes and also help to achieve a better impedance matching for the TEM modes in the transmission lines formed by the stripline electrodes and beam pipe in the kicker. The RF design and analysis of trapped resonant modes in the kicker were simulated by the 3-D electromagnetic code GdfidL [1]. Results of the RF design and analysis of trapped resonant modes will be discussed together with analytical estimates of coupled bunch instabilities at a beam current of 500 mA.
A remote-controlled robot-car in the TPS tunnel
Authors: Lee T Y , Chen B Y , Hsu T W , Huang B Y , Lin W Y , Kuo C H
Published: December 2019

A remote-controlled robot-car named “PhotonBot” was put into the TPS accelerator tunnel and is equipped with a 360 ° LiDAR for SLAM and navigation, two cameras for perception and first-person view, and a thermal imaging system. The robot can be remotely controlled and can send data to a remote PC through Wi-Fi. With SLAM, it can go more freely without being restricted to a designated path. In order to ensure it can work continuously, there is a wireless charging station in case of a low battery.
Archive System of Beam Injection Information at SuperKEKB
Authors: Kaji Hiroshi , Obina Takashi , Iitsuka Yuichi , Hirose Masaya
Published: December 2019

The injection archiver system is developed for the SuperKEKB collider. It records the information related to beam injection, pulse-by-pulse, so that the detailed studies of injection conditions become possible. The system is successfully operated during the phase-2 operation of SuperKEKB. The fluctuation and significant loss of injected current are observed with its new determination method. Besides, the recorded data can be utilized for studying the beam backgrounds related to the injection.
Beam Control and Monitors for the Spiral Injection Test Experiment
Authors: Rehman Muhammad Abdul , Iinuma Hiromi , Ohsawa Satoshi , Nakayama Hisayoshi , Furukawa Kazuro , Mibe Tsutomu , Hisamatsu Hiromi
Published: December 2019

A new experiment at J-PARC (E34) is under construction to measure the muon's g – 2 to unprecedented precision of 0.1 ppm and electric dipole moment up to the sensitivity of 10–21 e.cm in order to explore new physics beyond the standard model. A novel three-dimensional spiral injection scheme has been devised to inject and store the beam into a small diameter MRI-type storage magnet for E34. The new injection scheme features smooth injection with high storage efficiency for the compact magnet. However, spiral injection scheme is an unproven idea, therefore, a Spiral Injection Test Experiment (SITE) at KEK Tsukuba Campus is underway to establish this injection scheme. SITE consists of a 80keV thermionic electron gun, two-meter-long beamline, and a solenoid storage magnet. The DC electron beam spiral track has been confirmed by the de-excitation of the nitrogen gas in the vacuum chamber of the storage magnet. A new wire scanner system has been developed to extract the beam current, profile and geometrical information of three-dimensional trajectory.
Multi-Ribbon Profile Monitor for high power proton beam at J-PARC MR Abort Line
Authors: Sato K , Hashimoto Y , Sato Y , Igarashi S , Koseki T , Hamada E
Published: December 2019

Japan Proton Accelerator Research Complex (J-PARC) Main Ring (MR), the world-class high intensity proton synchrotron, provides proton beam to two experimental facilities with two extraction modes: Fast extraction (FX) and Slow extraction (SX). The number of protons per pulse (ppp) in MR recorded the world highest value of 2.7 × 1014 in the FX mode. Now we are planning to increase the ppp further up to 3.3 × 1014 in near future. The beam profile is one of the most important parameters to discuss the high intensity beam dynamics in MR. Monitors using multi-wires /ribbons are effective to measure the beam profile with good accuracy and wide dynamic range. However, they cause significant beam losses by interactions with high-intensity circulating beam in synchrotrons. Recently, we installed new multi-ribbon profile monitor (MRPM) in an abort line in MR. The abort line is one of the extracted beam lines of the FX system. It has a quadrupole doublet which is called Abort Q and transports extracted beam to a beam dump. The FX system can extract the circulating beam in MR with an arbitrary energy. Performing the single-pass measurement with MRPM and changing the transfer matrix by sweeping field strength of Abort Q, the emittance of the extracted beam can be measured. In this paper, we present the design, manufacturing, and results of the first beam test of newly installed MRPM system.
Study on the influence of beam transverse position on the cavity bunch length measurement
Authors: Wang Qian , Luo Qing , Sun Baogen
Published: December 2019

Monopole modes in the resonant cavities are wildly used to obtain the beam current and the bunch length, while dipole modes are used to measure the beam transverse position. It is generally recognized that the monopole modes are independent of the beam transverse offset. In this paper, the influence of beam transverse offset on the bunch length measurement using monopole modes is analyzed. The simulation results show that the relative error of the bunch length measurement is less than 1 % when the beam offset is within 1 mm.
A rotation method to calibrate BPM electric offsets
Authors: Wang M.W. , Wang D. , Wang Z.M. , Qiu M.T. , Zheng S.X. , Ma P.F. , Guan X.L. , Huang W.H. , Wang X.W.
Published: December 2019

Beam position monitor is a key instrument for machine commissioning. To measure beam position accurately, offline calibrations to acquire the sensitivity and offsets of the BPM are essential prerequisites. A new method to calibrate the BPM electric offset is proposed in this paper. By measuring the location variation of the BPM electric center after rotating the BPM 180 degrees, the BPM offset can be derived. The method is more convenient, universal and accurate than the traditional methods. The method is successfully applied to calibrate the button BPM of Xi’an Proton Application Facility. The repetitive measurement error is 20.8μm.
Design and simulation of thin eddy-current septum for injection of diffraction limited storing ring
Authors: Tong J , Gu M , Liu B , Liu Y , Wang R
Published: December 2019

Ultra-low emittance in Diffraction Limited Storage Ring (DLSR) usually has small Dynamic Aperture (DA), which makes the traditional off-axis injection inadequate. Fast kickers together with thin septum magnets or direct current lambertsons could support on-axis injection for closely-spaced bunches with small DA. Thin eddy-current septum prototype had been designed for injection with laminated silicon steel sheets as magnet core. Theoretical analysis and transient simulation had been carried out within OPERA software. Due to the minimum thickness of the septa is only 1 mm, several optimization approaches had been applied, such as shielding with strongly paramagnetic material and exciting with full cycle driving pulse, to satisfy the requirement that the leakage field is less than 0.1% with respect to the main one.
The preliminary long-term slow drift calibration study in low- level RF system
Authors: Lin Z.Y. , Du Y. C. , Huang W.H. , Tang J.H. , Tang C.X. , Huang G. , Xu Y.L , Zhang D. , Sun Z.C.
Published: December 2019

The phase drift of the RF signal in the low-level radio frequency (LLRF) system is observed in the long-term operation, which limits the performance and stability of the LLRF system. The long-term drift was reproduced in the lab. Its effect and sources of error were explored in the simple LLRF46 board and the simplest LLRF system. It is founded that the temperature will significantly lead to the phase distortion of the two signal channels, although with the same electron device. The distortion will finally cause the long-term drift with temperature floating. A fixed phase calibration signal (CAL signal) is applied to deal with the signal channels difference. The preliminary tests were conducted and the results were analysed.
HiRadMat: A Facility Beyond the Realms of Materials Testing
Authors: Harden F J , Bouvard A , Charitonidis N , Kadi Y
Published: December 2019

The ever-expanding requirements of high-power targets and accelerator equipment has highlighted the need for facilities capable of accommodating experiments with a diverse range of objectives. HiRadMat, a High Radiation to Materials testing facility at CERN has, throughout operation, established itself as a global user facility capable of going beyond its initial design goals. Pulsed high energy, high intensity, proton beams have been delivered to experiments ranging from materials testing, detector's prototype validation, radiation to electronics assessment and beam instrumentation. A 440 GeV/c proton beam is provided directly from the CERN SPS. Up to 288 bunches/pulse at a maximum pulse intensity of 3.5 × 1013 protons/pulse can be delivered. Through collaborative efforts, HiRadMat has developed into a state-of-the-art facility with improved in situ measurement routines, beam diagnostic systems and data acquisition techniques, offered to all users. This contribution summarises the recent experimental achievements, highlights previous facility enhancements and discusses potential future upgrades with particular focus on HiRadMat as a facility open to novel experiments.
RF Data Acquisition and Soft Alarm System for the Taiwan Photon Source
Authors: Liu Z. K. , Chang F. Y. , Chang L. H. , Chang M. H. , Chang S. W. , Chen L. J. , Chung F. T. , Li Y. T. , Lin M. C. , Lo C. H. , Wang C. , Yeh M. S. , Yu T. C.
Published: December 2019

The Taiwan Photon Source (TPS) is a modern, high brightness 3 GeV light source. A data acquisition program for the radio frequency (RF) system, including a transient data recorder, a long term data archiver and real time data monitoring, has been developed for the analysis of RF trips and RF system debugging. A soft alarm system is implemented as well utilizing EPICS and python packages. The hardware architecture and the functionality of the RF data acquisition and soft alarm system will be discussed in this article.
Progress and TDR plans of the Mechanical system of CEPC
Authors: Wang H , Bai S , Li M , Liu Y , Meng C , Qu H , Wang J , Zhang P , Zhou N
Published: December 2019

The TDR of CEPC is aimed at the key science and technology problems and makes preparations for the real project. This paper will describe the progress of mechanical system including the regular supports and transport vehicle design, the mockup plan, the installation scenario of machine detector interface (MDI) and the movable collimator, as well as the TDR plans of mechanical system.
Preparation of Titanum-Zirconium-Vanadium films by quantitative deposition
Authors: Shao J Q , Ge X Q , Wei W , Zhang B , Wang S H , Zhang Y X , Zhu B L , Chen C , Li W M , Wang Y
Published: December 2019

TiZrV has been used in vacuum technology and electric vacuum devices due to its high pumping speed and low activation temperature in recent years. At the same time, many preparation methods have been developed. Different from the current coating method of magnetron sputtering, this paper discusses the preparation of thin film coating from the viewpoint of vacuum sintering, which is flexible in design and more suitable for operation. Based on the analysis of the surface morphology of the sintered film, the feasibility and operability of the experimental method were explored from the surface compactness of the getter.
New small diameter rotating coil shaft for characterizing new generation of multipolar magnets
Authors: Campmany J. , Marcos J. , Massana V. , Ribó Ll. , Petrocelli R.
Published: December 2019

The proliferation of ultimate-light source facilities around the world has yielded the need of accurate characterization of small gap magnets. This also applies to multipolar magnets. Clearance diameters down to 10 mm for quadrupoles and sextupoles become to be used and need to be accurately measured. At these small gaps, the high order multipoles influence on electron beam dynamics is high, and it should be well characterized in order to guarantee a feasible operation of the accelerator. To face this challenge, ALBA magnetic measurement laboratory has developed a new rotating coil shaft with a diameter of 10 mm able to be introduced inside narrow-gap multipolar magnets. In this paper we present the design as well as the manufacturing of such a device.
The commission of the home-made 500MHz, 80kW solid-state amplifier in NSRRC
Authors: Yu T C , Wang Ch , Chang L H , Yeh M S , Lin M C , Lo C H , Chung F T , Chang M H , Chen L J , Liu Z K , Chang Fu-Yu , Chang S W , Li Yi-Da
Published: December 2019

Solid-state for high power RF application is an attracting and interesting technology which is now become popular in accelerator field. To adopt and master such technique, a 500MHz, 80kW solid-state amplifier is thus developed in NSRRC. The amplifier is consisted of 100 900W amplifier modules which are driving by identical modules. Each module contains input and output directional couplers and status monitoring circuits. To have longer life time and better performance, the RF power transistors are integrated with water cooled heat sink directly. In such a way, the transistors have higher output power and better efficiency. The RF power of each module is combined through coaxial combiner while its DC power is provided by parallel connected DC power supplies which can provide better redundancy and reliability. The home-made solid-state amplifier is demonstrated to have quite high quality RF power and reliability with acceptable power combination efficiency.
Design of the Neutron Imaging Differential Pumping Line at LLNL*
Authors: Caggiano J A , Castronovo D , Fitsos P , Gibson D J , Hall J , Johnson M S , Marsh R A , Rusnak B
Published: December 2019

The neutron imaging system at LLNL is a radiographic capability for imaging objects with fast, quasi-monoenergetic neutrons at ⩽1mm spatial resolution. The neutron production source is a deuteron beam (4 or 7 MeV) incident upon a rotating, high-pressure, windowless, pure-deuterium gas target. The windowless nature of the target combined with the high pressure leads to significant gas leakage upstream of the neutron production target. This leakage degrades the imaging quality by (1) increasing the depth-of-field blurring and (2) increasing the beam diameter and divergence in the transverse direction via angular straggling in the residual gas. To mitigate these effects, and guided by bench tests and simulations, we designed a differential pumping line (DPL) to ensure the highest quality imaging system. The system consists of three primary stages (chambers), each separated by carefully shaped apertures. These apertures can be long and thin with low-angle tapers due to the high quality of the beam optics (convergence at the target < 5mrad) and low emittance of the beam (~5 pi mm- mrad). The primary cascaded roots pumps are sized to remove >99% of the incoming mass flow in each stage, ensuring that by the third stage furthest from the target, turbomolecular pumps are able to operate in a nominal ~mTorr range. We anticipate full system testing with helium in mid 2019.
Data-driven Controller Design Using the CERN Power Converter Control Libraries (CCLIBS)
Authors: Nicoletti Achille , Martino Michele
Published: December 2019

The data-driven control approach is a control methodology in which a controller is designed without the need of a model. Parametric uncertainties and the associated unmodeled dynamics are therefore irrelevant; the only source of uncertainty comes from the measurement process. The CERN Power Converter Control Libraries (CCLIBS) have been updated to include data-driven H-infinity control methods recently proposed in literature. In particular, a two-step convex optimization algorithm is performed for obtaining the 2-degree-of-freedom controller parameters. The newly implemented tools in CCLIBS can be used both for frequency response measurement of the load and for controller synthesis. A case study is presented where these tools are used for an application in the CERN East Area Renovation Project for which a high-precision 900 A trapezoidal current pulse is required with 450 ms flat-top and 350 ms ramp-up and ramp-down times. The tracking error must remain within +/- 100 parts-per-million (ppm) during the flat-top (before the ramp-down phase starts). The magnet considered in the case study is of non-laminated iron type, hence the necessity of data-driven techniques since the dynamics of such a magnet is difficult to be modeled accurately (due to eddy currents losses). The power converter used is a SIRIUS 2P (with a current and voltage rating of 400 Arms and 450 V, respectively) whose digital control loop is regulated at a sampling rate of 5kS/s.
Stand-alone accelerator system based on SRF quarter-wave resonators
Authors: Kutsaev S V , Agustsson R , Berry R , Chao D , Conway Z A
Published: December 2019

Superconducting accelerators are large and complex systems requiring a central refrigerator and distributed transfer systems to supply 2-4 K liquid helium. Stand-alone, cryocooler-based systems are of interest both to scientific facilities and for industrial applications, as they do not require large cryogenic infrastructure and trained specialists for operation. Presented here is our approach to the challenge of using low-power commercially avail-able cryocoolers to operate niobium superconducting resonators at 4.4 K with high accelerating voltages and several watts of heating. Engineering and design results from RadiaBeam Systems, collaborating with Argonne National Laboratory, for a stand-alone liquid-cooled cryomodule with 10 Watts of 4.4 K cooling capacity housing a 72.75 MHz quarter-wave resonator operating at 2 MV for synchronous ions travelling at 7.7% of speed of light will be discussed.
Simulation of quench detection algorithms for Helmholtz Zentrum Berlin SRF cavities
Authors: Echevarria P , Garcia Arruabarrena B , Ushakov A , Jugo J , Neumann A
Published: December 2019

The Helmholtz Zentrum Berlin is carrying out two accelerator projects which make use of high gradient Continuous Wave (CW) Superconducting Radiofrequency (SRF) cavities: bERLinPro and BESSY-VSR. In both projects, a prompt detection of a quench is crucial to avoid damages in the cryomodules and cavities themselves. In this paper, the response of real time estimation of the cavity parameters using the transmitted and forward RF signals is simulated, in order to perform the quench detection. The time response of the estimated half bandwidth is compared with the dissipated energy in the cavity walls for the different type of SRF cavities used in both projects, i.e., bERLinPro’s photoinjector, booster and linac, and BESSY-VSR 1.5 GHz and 1.75 GHz cavities. As an intermediate step prior to the implementation in an mTCA.4 system together with the LLRF control and test with a real cavity, the algorithm has been implemented using a National Instruments FPGA board to check its proper behavior.
Tuning of a tapered ridge-loaded waveguide coupler for a drift tube linac of the compact pulsed hadron source
Authors: Lei Y , Zheng S , Xing Q , Tang R , Du C , Guan X , Wang X
Published: December 2019

This paper presents the tuning result of a tapered ridge-loaded waveguide coupler for the drift tube linac (DTL) of the compact pulsed hadron source (CPHS) at Tsinghua University. The coupler has been designed, manufactured, and mounted on the DTL cavity for the cold measurement and tuning. The iris diameter of the coupler which is related to the coupling coefficient needs to be determined in the tuning experiment, due to the difference between the designed and measured quality factors. Meanwhile, we found that the relationship between the coupling coefficient and iris diameter from the traditional analytical design method is not applicable when the iris diameter is relatively large. In this paper, the target coupling coefficient is analyzed, and the limit of the original analytical design is presented. The measurement method is introduced to improve the measurement efficiency and the tuning process of the coupling coefficient to the target value is described. After several iterations, the coupling coefficient is tuned to 1.54 which is close to the desired value of 1.56.
Multi-physics computation and deformation testing of a shell-type 1.5-GHz cavity
Authors: Lin M C , Yeh M K , Lu M R , Lo C H
Published: December 2019

A copper prototype of a 1.5-GHz cavity was manufactured to simulate a superconducting radio-frequency cavity for technique development. Frequency tuning with longitudinal compression of this prototype and cryogenic cooling with liquid nitrogen were performed to examine the numerical results from finite-element models, mainly the corresponding shifts of the fundamental resonant frequency. An appropriate element option improved the accuracy of the resonant frequency and the distribution of the magnetic field. Effects of geometry distortion of an uneven length on the frequency shift of this shell-type cavity as loaded on longitudinal compression are also examined and discussed.
Electromagnetic design of the low beta cavities for the JAEA ADS
Authors: Yee-Rendon B , Kondo Y , Maekawa F , Meigo S , Tamura J
Published: December 2019

The Japan Atomic Energy Agency (JAEA) is designing a superconducting CW proton linear accelerator for the ADS project. The superconducting region will use five types of radio frequency cavities. In the region from 2 to 180 MeV the acceleration will be done using Half Wave Resonator (HWR) and Single Spokes (SS) cavities. HWR cavities will accelerate the beam from 2 to 10 MeV with a geometrical beta of 0.08 and the SS ones will do from 10 to 180 MeV using two cavity families with geometrical betas of 0.16 and 0.43. The results of electromagnetic model design are presented and the comparison with similar cavities from other projects are included.
Modelling of electron acceleration in relativistic supernovae
Authors: Romansky V I , Bykov A M , Osipov S M
Published: December 2019

Radio and X-ray observations revealed a rare but a very interesting class of supernovae (SNe) with a sizeable fraction of the kinetic energy of ejecta moving with a trans-relativistic speed. These relativistic SNe are comprising a population of the objects intermediate between the numerous core collapse SNe expanding with non-relativistic velocities and the gamma-ray bursts with highly relativistic ejecta. An interpretation of the observed non-thermal emission from relativistic SNe requires a model of electron acceleration in trans-relativistic shocks. In this paper we present numerical Particle-in-Cell (PIC) simulation of electron spectra in trans-relativistic shock waves propagating in clumped stellar winds of the SN progenitors. It is shown here that the presence of background magnetic fluctuations has a drastical effect on the electron acceleration by the trans-relativistic shocks propagating transverse to the regular magnetic field in the clumped wind of a massive progenitor star.
Force on a moving proton vortex in a superfluid neutron star
Authors: Gusakov M E
Published: December 2019

A controversy is resolved about the form of the Lorentz-type force on proton vortices moving with respect to the bulk neutron-star matter. The result is important for modeling the evolution of stellar magnetic field.
On the possibility of research the photon-photon interaction at the European X-ray Free Electron Laser – European XFEL
Authors: Popov A N , Bobashev S V , Bezverkhnii N O , Sorokin A A
Published: December 2019

The possibility of performing the experimental research in the field of fundamental physics based on the unique instrument – European X-ray Free Electron Laser (E-XFEL) is considered in this paper. The calculations of the reaction γ + γ → e+ + e−
cross section for gamma quanta with E ∼ (1 − 100) GeV energy with X-ray photons are performed. The possibility of experimental registration of reaction γ + γ → e+ + e−
product are reviewed. Also, the optical depth of the interaction between gamma-rays with the E-XFEL’s photon pulses is estimated. Astrophysical applications are discussed.
Classification of gamma-ray bursts observed with Konus-Wind
Authors: Svinkin D S , Aptekar R L , Golenetskii S V , Frederiks D D , Ulanov M V , Tsvetkova A E
Published: December 2019

We present the analysis of duration and spectral-hardness distributions of ∼ 3000 gamma-ray bursts (GRBs) detected by Konus-Wind (KW) between November 1994 and early February 2019. We analyse burst T
50 and T
90 durations (the time intervals which contain the central 50% to 90% of the total burst count fluence, respectively) and argue that T
50 is more robust duration measure than T
90. Using a two log-normal component fit to the T
50 distribution we pick the boundary between the overlapping classes of short-duration and long-duration bursts to be at T
50 = 0.7 s, which implies the fraction of short GRBs (T
50
< 0.7 s) to be ∼ 17%. Using Gaussian mixture model fits we show that hardness-duration distribution can be well described by three Gaussian components, with two components corresponding to short/hard and long/soft GRB population, and the third component covering the softest GRBs with intermediate durations. This classification suggests that ∼ 14% KW GRBs are from short/hard population.

Finally we discuss a possibility to discriminate between physically distinct Type I and Type II GRBs with the help of hardness-duration distribution.
Detection of the PSR J1741+1351 white dwarf companion with the Gran Telescopio Canarias
Authors: Zyuzin D A , Kirichenko A Yu , Karpova A V , Shibanov Yu A , Zharikov S V , Fonseca E , Cabrera-Lavers A
Published: December 2019

We report detection of the binary companion to the millisecond pulsar J1741+1351 with the Gran Telescopio Canarias. The optical source position coincides with the pulsar coordinates and its magnitudes are g′ = 24.84(5), r′ = 24.38(4) and i′ = 24.17(4). Comparison of the data with the WD evolutionary models shows that the source can be a He-core WD with a temperature of ≈ 6000 K and a mass of ≈ 0.2M⊙. The latter is in excellent agreement with the companion mass obtained from the radio timing solution for PSR J1741+1351.
Glitches in neutron stars with magnetically decoupled core
Authors: Goglichidze O A , Barsukov D P
Published: December 2019

The magnetically decoupled core model was proposed earlier as a way to solve the problem of inconsistency between the neutron star long-period precession and superfluid vortex pinning which is the base of most theories of pulsar glitches. It was assumed that the pinning takes place in the region of the neutron star core which, being magnetically decoupled, can rotate relative to the crust. In present work some aspects of the glitch spin-up stage in the framework of the proposed model are discussed. Estimated spin-up time-scales are compared with observational data. According to the estimations the Crab pulsar is likely posses a magnetically decoupling core region, while the results for the Vela pulsar is more controversial.
Optical identification of binary system millisecond pulsar J1045−4509 with the VLT
Authors: Bobakov A V , Zyuzin D A , Shibanov Yu A
Published: December 2019

We analyse archival optical data on the binary companion to the millisecond pulsar J1045-4509 obtained with the Very Large Telescope. A possible optical counterpart candidate is found at the pulsar position. Its magnitudes are V > 26.4, R = 25.7(2) and I = 25.4(2). The data are compared with white dwarf evolutionary models. Depending on still poorly known distance to the pulsar, two alternative interpretations are possible. For the radio timing parallax distance, the candidate can be a very cool and old white dwarf with the hydrogen atmosphere and the temperature of < 3000 K and the age of > 5 Gyr. The dispersion measure distance suggests a younger (∼ 2 Gyr) and hotter (∼ 6000 K) white dwarf, whose atmosphere composition remains unknown.
Investigation of the asteroids Masaakikoyama (13553) and 5131 (1990 BG) during their close approaches to the Earth
Authors: Petrova S N , Devyatkin A V , Gorshanov D L , L’vov V N
Published: December 2019

Astrometric and photometric observations of two near-Earth asteroids having poorly-defined axial rotation periods – Masaakikoyama (13553) and 5131 (1990 BG) – were performed using two telescopes of the Pulkovo Observatory (CAO RAS). Both asteroids in question have proved to be very slow rotators with signs of tumbling. Using the data obtained their periods were derived (97.1 ± 0.2 and 157.82 ± 0.2 hours, respectively), dense lightcurves were obtained. Accuracy of the orbital elements of the asteroids was also improved.
Radiocarbon data from the Most Ancient Dryas to the Younger Dryas: cosmic rays and climate
Authors: Kudryavtsev I V , Dergachev V A
Published: December 2019

In the present work we consider the abundance of radiocarbon (Δ14C) in the Earth’s atmosphere in 12000-8500 BC years. Some periods of sharp cold and warming are fixed in this time interval. The so-called Younger Dryas (≈ 10700–9700 BC) is one of the most well known examples of dramatic change of terrestrial climate. The Younger Dryas (≈ 10700–9700 BC) lasted for ca one thousand years and a transition from the Last Glaciation to the interglacial Holocene has happened about 12 thousand years ago. During the Younger Dryas the amount of Δ14C increased within ≈ 10800 –10560 BC by 3% and it decreased by 6 % over a period 10560-9680BC. The reconstructions of the radiocarbon production rate and the heliospheric modulation potential based on 14C and 18O data sets are presents. The periods of extreme levels of these parameters are determined.
Boron Isotopes in the PAMELA Experiment
Authors: Bogomolov E A , Vasilyev G I
Published: December 2019

Analysis of the isotopic composition of nuclei in galactic cosmic rays (GCR) in the PAMELA orbital international experiment allows us to study the problems of the origin and propagation of cosmic rays in the Galaxy. Due to the high statistical and methodical accuracy, the PAMELA magnetic spectrometer data provided significant progress in the study of the isotopic composition of the light nuclei from H to Be in the GCR in the energy region of ∼0.1–1 GeV/nucleon and, for the first time, made it possible to estimate the contribution in GCR from local (∼100 pc) recent (∼106 years) interstellar sources (LS) from supernova explosions. An isotopic analysis of boron (B) nuclei in the GCR has so far been carried out only in the energy region ∼0.08–0.17 GeV/nucleon in the space experiments Voyager, Ulysses, ACE. In this work using the PAMELA data 2006-2014 about the rigidities of the detected nuclei and their speed (time of flight analysis (TOF) and ionization losses in a multilayer calorimeter) for the first time was made an attempt to determine the 11B/10B ratio in the energy range of ∼0.1–1.0 GeV/nucleon. The new PAMELA data are consistent with existing measurements and those expected from modeling, but the statistical and methodological accuracy of measurements does not allow us to separate the contribution of local boron sources to GCR. The results of the isotope analysis of boron nuclei in the GCR (spectra 10B, 11B and 11B/10B ratio depending on the rigidity and energy of the nuclei) in comparison with the existing measurement data and calculations will be presented.
Estimates dark halo parameters in S-galaxies
Authors: Butenko M , Kuzmin N , Nichiporov I
Published: December 2019

The dark mass problem is the most important for cosmology and galaxies physics. Various observational data of galaxies and galaxies clusters kinematics and dynamics require presence of massive dark matter. We estimate the dark mass within the galaxies optical radius using several different approaches, such as the maximum disk model, the marginal condition of the stellar disk gravitational stability and the vertical equilibrium condition in the galactic disk. The distribution functions of the relative dark mass within the optical radius Ropt
for a set of 50 galaxies are constructed. Most of the objects from our set have a relative mass within µ = 2. This agrees well with the results of numerical simulations.
Gravitational lensing probability for the Konus-Wind gamma-ray bursts detected in the triggered mode
Authors: Tsvetkova A E , Svinkin D S , Frederiks D D
Published: December 2019

Although half a century has passed since the discovery of Gamma-ray bursts (GRBs), there is no evidence for any strongly lensed event. Using GRB luminosity function and GRB formation rate estimates for the Konus-Wind burst sample with known redshifts, and a Singular Isothermal Sphere as a gravitational lens model, we predict the detection rate of both GRB images being ≈ 0.02–0.05 events per year. The result is consistent with the non-detection of lensed bursts in the KW triggered GRB sample.