The coherent synchrotron radiation （CSR） effect emittance dilution in high-brightness light sources and linear in a bending path plays an important role in transverse colliders, where the electron beams are of short...The coherent synchrotron radiation （CSR） effect emittance dilution in high-brightness light sources and linear in a bending path plays an important role in transverse colliders, where the electron beams are of short bunch length and high peak current. Suppression of the emittance growth induced by CSR is critical to preserve the beam quality and help improve the machine performance. It has been shown that the CSR effect in a double-bend achromat （DBA） can be analyzed with the two-dimensional point-kick analysis method. In this paper, this method is applied to analyze the CSR effect in a triple-bend achromat （TBA） with symmetric layout, which is commonly used in the optics designs of energy recovery linacs （ERLs）. A condition of cancelling the CSR linear effect in such a TBA is obtained, and is verified through numerical simulations. It is demonstrated that emittance preservation can be achieved with this condition, and to a large extent, has a high tolerance to the fluctuation of the initial transverse phase space distribution of the beam.展开更多
When an electron bunch is compressed in a chicane compressor, the CSR （coherent synchrotron radiation） will induce energy redistribution along the bunch. Such energy redistribution will affect the longitudinal emitt...When an electron bunch is compressed in a chicane compressor, the CSR （coherent synchrotron radiation） will induce energy redistribution along the bunch. Such energy redistribution will affect the longitudinal emittance as a direct consequence. It will also excite betatron oscillation due to the chromatic transfer functions, and hence a transverse emittance change. So, it is indispensable for us to find a way to alleviate the CSR-caused emittance dilution and the bad result of chicane compressor in PKU-FEL.展开更多
The emittance growth induced by Coherent Synchrotron Radiation （CSR） is an important issue when electron bunches with short bunch length and high peak current are transported in a bending magnet. In this paper, a si...The emittance growth induced by Coherent Synchrotron Radiation （CSR） is an important issue when electron bunches with short bunch length and high peak current are transported in a bending magnet. In this paper, a single kick method is introduced that could give the same result as the R-matrix method, but is much easier to use. Then, with this method, an optics design technique is introduced that could minimize the emittance dilution within a single achromatic cell.展开更多
基金Supported by National Natural Science Foundation of China(11475202,11405187)Youth Innovation Promotion Association of Chinese Academy of Sciences(2015009)
文摘The coherent synchrotron radiation （CSR） effect emittance dilution in high-brightness light sources and linear in a bending path plays an important role in transverse colliders, where the electron beams are of short bunch length and high peak current. Suppression of the emittance growth induced by CSR is critical to preserve the beam quality and help improve the machine performance. It has been shown that the CSR effect in a double-bend achromat （DBA） can be analyzed with the two-dimensional point-kick analysis method. In this paper, this method is applied to analyze the CSR effect in a triple-bend achromat （TBA） with symmetric layout, which is commonly used in the optics designs of energy recovery linacs （ERLs）. A condition of cancelling the CSR linear effect in such a TBA is obtained, and is verified through numerical simulations. It is demonstrated that emittance preservation can be achieved with this condition, and to a large extent, has a high tolerance to the fluctuation of the initial transverse phase space distribution of the beam.
基金National Nature Science Foundation of China (10276001)
文摘When an electron bunch is compressed in a chicane compressor, the CSR （coherent synchrotron radiation） will induce energy redistribution along the bunch. Such energy redistribution will affect the longitudinal emittance as a direct consequence. It will also excite betatron oscillation due to the chromatic transfer functions, and hence a transverse emittance change. So, it is indispensable for us to find a way to alleviate the CSR-caused emittance dilution and the bad result of chicane compressor in PKU-FEL.
文摘The emittance growth induced by Coherent Synchrotron Radiation （CSR） is an important issue when electron bunches with short bunch length and high peak current are transported in a bending magnet. In this paper, a single kick method is introduced that could give the same result as the R-matrix method, but is much easier to use. Then, with this method, an optics design technique is introduced that could minimize the emittance dilution within a single achromatic cell.
