Author: Ren, Z.L.
Paper Title Page
MOPAB074 Preliminary Study of Design Method for Hybrid MBA Lattice 297
 
  • J.J. Tan, Z.H. Bai, Z.L. Ren, J.H. Xu
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
  • Q. Zhang
    INEST, Hefei, People’s Republic of China
 
  Nonlinear optimization of hybrid multi-bend-achromat (HMBA) lattice is a difficult task due to its quite limited variables of multipole magnets. As a result, it is necessary to consider nonlinear potential of the lattice in its linear design. Nonlinear dynamics can be estimated by nonlinear driving terms and detuning terms. In this paper, we propose a design method for HMBA lattice. In this method, objective functions include emittance and two indicators of nonlinear dynamics, which consist of nonlinear driving terms and detuning terms. As an example, an HMBA lattice for a 2.2 GeV storage ring with circumference of 460.8 m was designed to demonstrate the method.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB074  
About • paper received ※ 19 May 2021       paper accepted ※ 21 May 2021       issue date ※ 21 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
MOPAB112 A Modified Hybrid 6BA Lattice for the HALF Storage Ring 407
 
  • Z.H. Bai, G.Y. Feng, T.L. He, W. Li, W.W. Li, G. Liu, Z.L. Ren, L. Wang, P.H. Yang, S.C. Zhang, T. Zhang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  In this paper, we propose a modified hybrid 6BA lattice as the baseline lattice of the Hefei Advanced Light Facility (HALF) storage ring. Similar to the Diamond-II lattice, the proposed lattice cell has one long straight section and one mid-straight section; but the two bend units adjacent to the mid-straight are LGB/RB units (LGB: longitudinal gradient bend, RB: reverse bend), which can give both lower emittance and shorter damping times. The designed HALF storage ring, with an energy of 2.2 GeV and 20 lattice cells, has a natural emittance of about 85 pm·rad.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-MOPAB112  
About • paper received ※ 15 May 2021       paper accepted ※ 20 May 2021       issue date ※ 01 September 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
TUPAB368 Design of the Longitudinal Gradient Dipole Magnets for HALF 2378
 
  • M.Y. Mingyao
    Wang, Hefei, People’s Republic of China
  • G.Y. Feng, Z.L. Ren, H. Xu
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  Hefei Advanced Light Facility (HALF) is the fourth generation diffraction-limited storage ring light source project in China. The lattice of the storage ring consists of six different dipoles with longitudinal gradients. The longitudinal-gradient dipoles (LGBs) are permanent magnets. This paper presents the designed construction of LGBs and the magnetic field results using OPERA3D. By optimizing the shape of the polar surface, the magnetic field uniformity is optimized to about 5×10-4. With some movable adjusting block, the magnetic field can be controlled accurately. The temperature stability of the magnet is better than 0.0074 T*mm/°C by setting temperature compensating shunt.  
poster icon Poster TUPAB368 [0.862 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB368  
About • paper received ※ 15 May 2021       paper accepted ※ 02 June 2021       issue date ※ 10 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPAB263 Complex Unit Lattice Cell for Low-Emittance Synchrotrons 3254
 
  • Z.L. Ren, Z.H. Bai, J.J. Tan, L. Wang, H. Xu, P.H. Yang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  To reach the real diffraction-limited emittance, it is generally required to increase the number of bends in multi-bend achromat (MBA) lattices that are used in the designs of fourth-generation synchrotron light sources. For an MBA lattice with distributed chromatic correction, more bends mean much tighter space and much stronger magnets. Inspired by the hybrid MBA lattice concept, in this paper we propose a new lattice concept called complex unit lattice cell, which can save space and reduce magnet strengths. A 17BA lattice based on the complex unit cell concept is designed for a 3 GeV synchrotron light source with a circumference of 537.6 m, which reaches a natural emittance of about 21 pm·rad. Comparison is also made between this 17BA lattice and the 17BA lattice with distributed chromatic correction to demonstrate the merit of the complex unit cell concept.  
poster icon Poster WEPAB263 [1.279 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB263  
About • paper received ※ 16 May 2021       paper accepted ※ 02 July 2021       issue date ※ 12 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
WEPAB264 MOGA Optimization of Superconducting Longitudinal Gradient Bend Based on NbTi Wire 3257
 
  • C. Chen, Z.H. Bai, G.Y. Feng, Z.L. Ren, Zh.X. Tang, L. Wang, H. Xu
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
 
  Funding: Work supported by National Key Research and Development Program of China, (2016YFA0402001)
Multi-bend achromat lattices with unit cells have been used in diffraction-limited storage ring designs. The longitudinal gradient bend can reduce the horizontal emittance below the theoretical minimum of a given magnet structure, and generally the horizontal emittance reduces with the peak field grows. Therefore superconducting longitudinal gradient bend (SLGB) can produce higher peak field value and quasi-hyperbolic field profile to minimize emittance at location of radiation and generate better hard X-rays. NbTi conductor, rather than Nb3Sn conductor, is selected to keep the design and manufacture of SLGB magnet as simple as possible. In this paper, how the field profiles of race-track type coil and solenoid coil change with their geometric parameters is studied, and multi-objective genetic algorithm is used to optimize SLGB magnet structure considering Hefei Advanced Light Facility lattice design demand and NbTi critical current.
 
poster icon Poster WEPAB264 [1.476 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-WEPAB264  
About • paper received ※ 14 May 2021       paper accepted ※ 05 July 2021       issue date ※ 14 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPAB073 Study of Seven-Bend-Achromat Lattice Option for Half 3926
 
  • J.H. Xu, Z.H. Bai, Z.L. Ren, J.J. Tan, P.H. Yang
    USTC/NSRL, Hefei, Anhui, People’s Republic of China
  • Q. Zhang
    INEST, Hefei, People’s Republic of China
 
  A seven-bend-achromat (7BA) storage ring lattice design for Hefei Advanced Light Facility (HALF) with a beam energy of 2.2 GeV and a circumference of 388.8 m is presented. The 7BA lattice is designed with the combined function bends and reverse bends which has a natural emittance of about 67 pm·rad. Two lattice candidates with different tunes have been selected. One lattice has better nonlinear dynamic performance for off-axis injection. The other lattice provides lower beta functions at the center of straight sections. The results of these studies are discussed in this paper.  
poster icon Poster THPAB073 [1.146 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB073  
About • paper received ※ 15 May 2021       paper accepted ※ 28 July 2021       issue date ※ 16 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)