Continuous Beam Steering Through Broadside Using Asymmetrically Modulated Goubau Line Leaky-Wave Antennas

Goubau line is a single-conductor transmission line, featuring easy integration and low-loss transmission properties. Here, we propose a periodic leaky-wave antenna (LWA) based on planar Goubau transmission line on a thin dielectric substrate. The leaky-wave radiations are generated by introducing periodic modulations along the Goubau line. In this way, the surface wave, which is slow-wave mode supported by the Goubau line, achieves an additional momentum and hence enters the fast-wave region for radiations. By employing the periodic modulations, the proposed Goubau line LWAs are able to continuously steer the main beam from backward to forward within the operational frequency range. However, the LWAs usually suffer from a low radiation efficiency at the broadside direction. To overcome this drawback, we explore both transversally and longitudinally asymmetrical modulations to the Goubau line. Theoretical analysis, numerical simulations and experimental results are given in comparison with the symmetrical LWAs. It is demonstrated that the asymmetrical modulations significantly improve the radiation efficiency of LWAs at the broadside. Furthermore, the measurement results agree well with the numerical ones, which experimentally validates the proposed LWA structures. These novel Goubau line LWAs, experimentally demonstrated and validated at microwave frequencies, show also great potential for millimeter-wave and terahertz systems

A data analysis method for isochronous mass spectrometry using two time-of-flight detectors at CSRe

The concept of isochronous mass spectrometry (IMS) applying two time-of-flight (TOF) detectors originated many years ago at GSI. However, the corresponding method for data analysis has never been discussed in detail. Recently, two TOF detectors have been installed at CSRe and the new working mode of the ring is under test. In this paper, a data analysis method for this mode is introduced and tested with a series of simulations. The results show that the new IMS method can significantly improve mass resolving power via the additional velocity information of stored ions. This improvement is especially important for nuclides with Lorentz factor $\gamma$-value far away from the transition point $\gamma _t$ of the storage ring CSRe.Comment: published in Chinese Physics C Vol. 39, No. 10 (2015) 10620

Time and Position-sensitive Foil MCP Detector for Mass Measurements at the Rare-RI Ring

埼玉大学博士(理学)xv, 233 p.High accuracy and precise mass measurements of exotic nuclei are very important for the study of nuclear physics and nuclear astrophysics. To increase the accuracy and extend the capability of now existing storage ring techniques for mass measurements, a newly constructed storage ring, the Rare-RI Ring, operating as an isochronous Mass Spectrometry （IMS） in RIKEN Nishina center to measure the mass of rare radioactive ions with a target precision of 10-6 for even one event during a time of flight （TOF） less than 1 millisecond, has been commissioned and studied experimently. To satisfy the requirements of high resolution, good accuracy, very fast and efficient mass measurements with the Rare RI Ring as an IMS, the TOF and extra velocity/magnetic-rigidity （for TOF correction） have to be measured with required accuracy and high resolution. Therefore, a high efficiency, good resolution for both timing and position, large effective area and low energy loss detector are dispensable. For these reasons, the study of the principle of mass measurements via the new obit-IMS method （IMS TOF with extra velocity/magnetic-rigidity correction） by the Rare-RI Ring and the development of the high performance detector described are carried out in this thesis. An experiment aimed to study the performance of the Rare RI Ring performing as an Isochronous mass spectroscopy （IMS） and the principle of IMS mass measurements with additional velocity or momentum measurements has been carried out at RIBF. In-flight fission fragments, created by 238U projectiles in a beryllium target at the entrance of the BigRIPS focus F0, were spatially separated by the BigRIPS-HA-SHARAQ beam-lines and injected into the Rare-RI Ring. In the experiment, we succeeded in selection, injection, accumulation and extraction of 5 different nuclei to R3 for mass determination and the isochronism ～5x10-6 was achieved by checking the TOF spectrum of 78Ge. A two stage selection and particle identification method has been carried out with the Bρ-TOF-ΔE-E method based on individual injection technique, and with this new method, all the ions have be well separated and identified for mass deduction analysis. The analysis of the data was done to investigate and verify that the IMS method with extra velocity or magnetic-rigidity correction can increase the mass accuracy and precision with a large momentum acceptance other than only using the IMS method without extra correction. It is proved that to achieve a high resolution, the revolution time measurement of the storied ions and the magnetic rigidity or the velocity for correction of the in ring TOF should be simultaneously measured, thus we can achieve higher resolution with small systematic error to cover relative large range of δm/m relative to reference ion in isochronous condition for the IMS method. From the analysis, it is also confirmed that from one experiment run, two complementary mass measurements methods （IMS and Bρ-TOF） can be employed simultaneously to deduce masses and benefit each other, in which it is very suitable to save beam time and cover large area of nuclide of chart and large momentum area of secondary products from experiment of very exotic nuclei. Besides, the first new mass of 74Ni which is not included in the newest atomic mass evolution （2016） is deduced in this work by Bρ-TOF method at the Rare-RI-Ring. The mass of 74Ni is very important for the research of nuclear shell effect and also shows importance of the impact on the r-process modeling. The pioneering mass measurements experiment by using two complementary time-of-flight methods （Bρ-TOF and IMS） simultaneously in one experiment run for mass determination in the world has been realized and verified within this work. In the in-flight fission experiment, there is large energy loss in the PPAC at F6 dispersive focus, which is for position measurement to deduce the momentum have large influence to the mass accuracy. At the same time the timing resolution of MCP detector of about 200 ps can not satisfy the high resolution mass measurements form the TOF. For these reasons, a electrostatic large-area thin-foil MCP detector was developed at the RIBF, which possess a higher timing resolution and has a capability to measure the position （to deduce velocity and magnetic-rigidity） at the same time with low energy loss and a large active area. The specification and performance of different position-sensitive anode that can be coupled with MCPs for position measurements have been studied systematically. A 2-dimentional delay-line type anode with dual wires for each coordinate are been chosen and utilized for our final design. The secondary electrons （SEs） electro-magnetic motion and trajectory in the detector are studied theoretically and by simulation. To calibrate the delay-line MCP detector （DLD120） system, a higher order calibration method is carried out and the precision and accuracy of the DLD120 system is discussed for different calibration methods. An isochronous condition for the operation of the electrostatic detector was calculated and studied by simulation. To characterize and optimize the timing and position resolution of the detector, the position resolution dependence of high voltage supplies has been studied both in the isochronous and non-isochronous condition by simulation and experimentally with 241Am alpha source. The detection efficiency and position resolution by using a carbon foil with thickness of 60 μg/cm2 or 2 μmm mylar foil coated with aluminium as SEs emitters are studied with variations of HV supplies of the detector potential plates. Two ex periments aimed at studying the performance （efficiency, timing and position resolution） of the position-sensitive timing detector were conducted at HIMAC （Heavy Ion Medical Accelerator in Chiba） with heavy ion beam for the detector with different grid pitch of 1mm and 3mm for the outer mirror. The performance of the detector have been optimized and the best achieved timing resolution and position is ≤ 50 ps and 1 mm in σ respectively, for which the detection efficiency is ～ 95 %. The performance of another same type of mirror detector coupled with timing anode which is dedicated for TOF measurement has been studied by heavy ions at HIMAC . The best achieved timing resolution is ～ 40 ps （in σ） and detection efficiency is ～ 96 % for heavy ion beams. This timing detector will be used for revolution time measurement inside R3, start TOF detector of the total TOF for in-ring circulation, beam-line TOF measurement for beam-line mass determination and velocity reconstruction for in-ring mass correction. Prospects of mass measurements at the Rare RI Ring employing the two complementary time-of-flight methods （Bρ-TOF and Orbit-IMS） have been demonstrated and the versatility of the fast low-energy-loss position-sensitive timing detector developed within this work in use for in-ring and on beam-line are discussed and summarized. Other next generation facilities with storage rings which are in plan to perform IMS mass measurements and possible new methods are summarized.1 Introduction 1 1.1 The history and present of mass spectrometry . . . . . . . . . . . . . . . . 1 1.2 Nuclear masses and mass models . . . . . . . . . . . . . . . . . . . . . . . 5 1.3 Physics motivation for mass measurements at storage rings . . . . . . . . . 10 1.3.1 Nuclear Structure Studies . . . . . . . . . . . . . . . . . . . . . . 11 1.3.2 Test of nuclear mass models and mass formulas . . . . . . . . . . . 12 1.3.3 Nuclear astrophysics . . . . . . . . . . . . . . . . . . . . . . . . . 13 1.4 Techniques for mass measurements . . . . . . . . . . . . . . . . . . . . . . 21 1.4.1 Indirect techniques . . . . . . . . . . . . . . . . . . . . . . . . . . 21 1.4.2 Direct techniques . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 2 TOF Mass measurements at the Rare-RI Ring and high resolution beam-line 37 2.1 Rare-RI Ring at RIBF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 2.2 Overview of present machine study experiments at the Rare-RI Ring . . . . 39 2.3 In-flight fission for mass measurements at the Rare-RI Ring . . . . . . . . . 41 2.3.1 Primary beam production . . . . . . . . . . . . . . . . . . . . . . 41 2.3.2 Secondary beam production, separation and particle identification . 42 2.3.3 Setup of beam-lines in conjunction with the Rare-RI-Ring as IMS . 44 2.3.4 Setup of BigRIPS and High-resolution beam-line as Bρ-TOF Mass Spectrometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 2.3.5 Introduction of the SHARAQ spectrometry . . . . . . . . . . . . . 46 2.4 Analysis of mass measurements experiment of 238U fission fragments . . . 47 2.4.1 Particle identification (PID) . . . . . . . . . . . . . . . . . . . . . 47 3 Results of in-flight fission mass measurement experiment 55 3.1 Analysis results of Obit-IMS mass measurements . . . . . . . . . . . . . . 55 3.1.1 Confirmation of circulation of RIs in the Rare-RI Ring . . . . . . . 57 3.1.2 Isochronicity curve . . . . . . . . . . . . . . . . . . . . . . . . . . 58 3.1.3 Extraction of RIs from the Rare-RI Ring . . . . . . . . . . . . . . . 58 3.1.4 Double kicker TOF . . . . . . . . . . . . . . . . . . . . . . . . . . 59 3.1.5 d E-E for PID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 3.1.6 Nuclear mass and m/q of bare ion . . . . . . . . . . . . . . . . . . 61 3.1.7 Velocity and momentum correction IMS mass measurements . . . . 62 3.2 Analysis results of Bρ-TOF mass measurements . . . . . . . . . . . . . . . 68 3.2.1 TOF determination with magnetic rigidity correction . . . . . . . . 68 3.2.2 Mass fit procedure . . . . . . . . . . . . . . . . . . . . . . . . . . 72 3.3 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82 4 The Rare-RI Ring and high resolution beam-line at RIBF 85 4.1 Introduction of MCP detectors for mass measurements . . . . . . . . . . . 85 4.2 Requirements of detectors for high precision and accuracy mass measurements 87 4.3 The electrostatic detector . . . . . . . . . . . . . . . . . . . . . . . . . . . 89 4.3.1 Description of the electrostatic mirror detector . . . . . . . . . . . 89 4.3.2 Principles for timing and/or position sensitive MCP detector for heavy nuclei . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 4.4 Conversion foils and grid . . . . . . . . . . . . . . . . . . . . . . . . . . . 96 4.5 Micro-channel plate (MCP) . . . . . . . . . . . . . . . . . . . . . . . . . . 98 4.5.1 Introduction of MCP . . . . . . . . . . . . . . . . . . . . . . . . . 98 4.5.2 MCP Operating principle and structure . . . . . . . . . . . . . . . 99 4.6 Anodes for position sensitive MCP . . . . . . . . . . . . . . . . . . . . . 101 4.6.1 Delay-Line Anodes (DL) . . . . . . . . . . . . . . . . . . . . . . . 101 4.6.2 Selection of anode . . . . . . . . . . . . . . . . . . . . . . . . . . 105 4.7 Simulation for the electrostaic detector . . . . . . . . . . . . . . . . . . . . 105 4.8 The performance of delay-line anode MCP detector . . . . . . . . . . . . . 113 4.8.1 The delay line anode . . . . . . . . . . . . . . . . . . . . . . . . . 113 4.8.2 Preparation, assembly and mounting of the Delay-line detector . . . 114 4.8.3 The high voltage supply for DLD and the foil detector . . . . . . . 117 4.8.4 The delay-line and MCP signal, the signal processing . . . . . . . . 122 5 Foil-MCP Detector Experimental Test 125 5.1 Calibration of the MCP with helical delay-lines . . . . . . . . . . . . . . . 125 5.2 Offline test of the electrostatic detector with DLD120 . . . . . . . . . . . . 147 5.2.1 Experimental setup and basis of analysis . . . . . . . . . . . . . . . 147 5.2.2 Offline test results with alpha source . . . . . . . . . . . . . . . . . 155 5.3 Online test of the electrostatic detector . . . . . . . . . . . . . . . . . . . . 168 5.3.1 Position-sensitive timing detector online test . . . . . . . . . . . . 168 5.3.2 Timing electrostatic detector online test . . . . . . . . . . . . . . . 185 5.4 Summary and Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . 188 6 Summary and prospects 191 6.1 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191 6.2 Outlook . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193 6.2.1 Other next generation facilities with storage rings for mass measurements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194 References 197 Appendix A Principle of Isochronous Mass Spectrometry 209 A.1 Principle of Isochronous Mass Spectrometry (IMS) by the Rare-RI Ring . . 209 A.1.1 Principle of orbit-IMS method at Rare-RI Ring . . . . . . . . . . . 213 A.2 Magnets and Isochronous field of the Rare-RI Ring . . . . . . . . . . . . . 219 Appendix B Specifications and Properties of MCPs & Storage, Handling and Operation of MCP 223 B.1 Rectangular type chevron MCP . . . . . . . . . . . . . . . . . . . . . . . . 223 B.1.1 Specifications and properties of rectangle-type MCP . . . . . . . . 223 B.2 Circle type chevron MCP . . . . . . . . . . . . . . . . . . . . . . . . . . . 224 B.3 Storage, Handling and Operation of Micro-channel Plates (from PHOTONIS)226 Appendix C Dimensions 229 Appendix D Analysis of m/q resolution by beam-line detectors 231指導教員 : 上坂友洋textapplication/pdfdoctoral thesi

Time and Position-sensitive Foil MCP Detector for Mass Measurements at the Rare-RI Ring

学位記号番号 : 博理工甲第1094号博士の専攻分野の名称 : 博士(理学) 学位授与年月日 : 平成30年9月21日textapplication/pdfthesi

Some Operations on Quaternion Numbers

In this article, we give some equality and basic theorems about quaternion numbers, and some special operations.Li Bo - Qingdao University of Science and Technology, ChinaLiang Xiquan - Qingdao University of Science and Technology, ChinaWang Pan - Qingdao University of Science and Technology, ChinaZhuang Yanping - Qingdao University of Science and Technology, ChinaGrzegorz Bancerek. The ordinal numbers. Formalized Mathematics, 1(1):91-96, 1990.Czesław Byliński. The complex numbers. Formalized Mathematics, 1(3):507-513, 1990.Czesław Byliński. Functions and their basic properties. Formalized Mathematics, 1(1):55-65, 1990.Czesław Byliński. Functions from a set to a set. Formalized Mathematics, 1(1):153-164, 1990.Czesław Byliński. Some basic properties of sets. Formalized Mathematics, 1(1):47-53, 1990.Fuguo Ge. Inner products, group, ring of quaternion numbers. Formalized Mathematics, 16(2):135-139, 2008, doi:10.2478/v10037-008-0019-x.Krzysztof Hryniewiecki. Basic properties of real numbers. Formalized Mathematics, 1(1):35-40, 1990.Xiquan Liang and Fuguo Ge. The quaternion numbers. Formalized Mathematics, 14(4):161-169, 2006, doi:10.2478/v10037-006-0020-1.Andrzej Trybulec. Enumerated sets. Formalized Mathematics, 1(1):25-34, 1990.Andrzej Trybulec and Czesław Byliński. Some properties of real numbers. Formalized Mathematics, 1(3):445-449, 1990.Zinaida Trybulec. Properties of subsets. Formalized Mathematics, 1(1):67-71, 1990.Edmund Woronowicz. Relations and their basic properties. Formalized Mathematics, 1(1):73-83, 1990.Edmund Woronowicz. Relations defined on sets. Formalized Mathematics, 1(1):181-186, 1990

Bloch surface plasmon enhanced blue emission from InGaN/GaN light-emitting diode structures with Al-coated GaN nanorods

InGaN/GaN light-emitting diode structures with Al-coated GaN nanorods were fabricated by using soft ultraviolet nanoimprint lithography. The intensity of light emission was found to be greatly enhanced due to the strong near-fields confined at the interface of Al/GaN and extended to the multiple quantum wells (MQWs) active region. The dynamics of carrier recombination and plasmon-enhanced Raman scattering were also investigated, providing a progressive view on the effective energy transfer between MQWs and surface plasmons.This work was supported by Special Funds for Major State Basic Research Project (Nos. 2011CB301900 and 2012CB619304), the Hi-tech Research Project (No. 2014AA032605), National Nature Science Foundation of China (Nos. 11104130, 61274003, 60990311, 61176063, and 61422401), the Program for New Century Excellent Talents in University (No. NCET-11-0229), Nature Science Foundation of Jiangsu Province (Nos. BK2011556, BK2011010, BK2010385, BY2013077, and BE2011132), Funds of Key Laboratory (No. 9140C140102120C14), Scientific Innovation Research of College Graduate in Jiangsu Province (CXZZ12_0052), PAPD, the Fundamental Research Funds for the Central Universities, the Research Funds from NJUYangzhou Institute of Opto-electronics, and the Australian Research Council Discovery Early Career Researcher Award (DE130101700)

Debris Flow Annual Frequency and Sediment Delivery Variations Compared to Rainfall Changes Over the Last 40 Years (Jiangjia Gully, China)

Natural hazards occur more frequently due to ongoing global climate change, which has increased the impact of precipitation. Debris flows and their relative activities have also changed over the past 39 years at Jiangjia Gully, a typical debris flow valley with high-frequency debris flows located in the Yunnan Province of China. This paper concentrates on the responses of sediment transportation induced by debris ows at Jiangjia Gully to rainfall change, using statistical analysis of the observation data of debris ows and rainfall. The results showed that: (1) the annual precipitation and rainy season precipitation both decreased in uctuation over the past over 40 years and experienced two high rainfall stages and one low rainfall stage; (2) the days of the daily precipitation that exceeded 20mm, 30mm, and 50mm changed in dissimilarity, and the days with over 20mm of daily precipitation increased slowly and with over 30mm and 50mm both decreased slowly; (3) the sediment amount transported by debris flow generally increased with just a little fluctuation in the past 40 years, which was consistent with the change in annual precipitation and the days with over 20mm of daily precipitation; and (4) the sediment transported by debris ow had a good relativity to annual precipitation and the days with over 20mm of daily precipitation. The frequency of debris flow occurrence has a good relativity to the rainy season precipitation and the days with over 20mm of daily precipitation, and their correlation coefficients are 0.4454 and 0.4737, respectively. The work can provide a scientific basis for the long-term forecast and prevention of debris flows