TY - JOUR
T1 - Demonstration of low emittance in the Cornell energy recovery linac injector prototype
AU - Gulliford, Colwyn
AU - Bartnik, Adam
AU - Bazarov, Ivan
AU - Cultrera, Luca
AU - Dobbins, John
AU - Dunham, Bruce
AU - Gonzalez, Francisco
AU - Karkare, Siddharth
AU - Lee, Hyeri
AU - Li, Heng
AU - Li, Yulin
AU - Liu, Xianghong
AU - Maxson, Jared
AU - Nguyen, Christian
AU - Smolenski, Karl
AU - Zhao, Zhi
PY - 2013/7/16
Y1 - 2013/7/16
N2 - We present a detailed study of the six-dimensional phase space of the electron beam produced by the Cornell Energy Recovery Linac Photoinjector, a high-brightness, high repetition rate (1.3 GHz) DC photoemission source designed to drive a hard x-ray energy recovery linac (ERL). A complete simulation model of the injector has been constructed, verified by measurement, and optimized. Both the horizontal and vertical 2D transverse phase spaces, as well as the time-resolved (sliced) horizontal phase space, were simulated and directly measured at the end of the injector for 19 and 77 pC bunches at roughly 8 MeV. These bunch charges were chosen because they correspond to 25 and 100 mA average current if operating at the full 1.3 GHz repetition rate. The resulting 90% normalized transverse emittances for 19 (77) pC/bunch were 0.23±0.02 (0.51±0.04) μm in the horizontal plane, and 0.14±0.01 (0.29±0.02) μm in the vertical plane, respectively. These emittances were measured with a corresponding bunch length of 2.1±0.1 (3.0±0.2) ps, respectively. In each case the rms momentum spread was determined to be on the order of 10-3. Excellent overall agreement between measurement and simulation has been demonstrated. Using the emittances and bunch length measured at 19 pC/bunch, we estimate the electron beam quality in a 1.3 GHz, 5 GeV hard x-ray ERL to be at least a factor of 20 times better than that of existing storage rings when the rms energy spread of each device is considered. These results represent a milestone for the field of high-brightness, high-current photoinjectors.
AB - We present a detailed study of the six-dimensional phase space of the electron beam produced by the Cornell Energy Recovery Linac Photoinjector, a high-brightness, high repetition rate (1.3 GHz) DC photoemission source designed to drive a hard x-ray energy recovery linac (ERL). A complete simulation model of the injector has been constructed, verified by measurement, and optimized. Both the horizontal and vertical 2D transverse phase spaces, as well as the time-resolved (sliced) horizontal phase space, were simulated and directly measured at the end of the injector for 19 and 77 pC bunches at roughly 8 MeV. These bunch charges were chosen because they correspond to 25 and 100 mA average current if operating at the full 1.3 GHz repetition rate. The resulting 90% normalized transverse emittances for 19 (77) pC/bunch were 0.23±0.02 (0.51±0.04) μm in the horizontal plane, and 0.14±0.01 (0.29±0.02) μm in the vertical plane, respectively. These emittances were measured with a corresponding bunch length of 2.1±0.1 (3.0±0.2) ps, respectively. In each case the rms momentum spread was determined to be on the order of 10-3. Excellent overall agreement between measurement and simulation has been demonstrated. Using the emittances and bunch length measured at 19 pC/bunch, we estimate the electron beam quality in a 1.3 GHz, 5 GeV hard x-ray ERL to be at least a factor of 20 times better than that of existing storage rings when the rms energy spread of each device is considered. These results represent a milestone for the field of high-brightness, high-current photoinjectors.
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U2 - 10.1103/PhysRevSTAB.16.073401
DO - 10.1103/PhysRevSTAB.16.073401
M3 - Article
AN - SCOPUS:84883527101
SN - 1098-4402
VL - 16
JO - Physical Review Special Topics - Accelerators and Beams
JF - Physical Review Special Topics - Accelerators and Beams
IS - 7
M1 - 073401
ER -