Author/Authors :
Takayama، نويسنده , , Yasuhiro and Takaya، نويسنده , , Noriko and Miyahara، نويسنده , , Tsuneaki and Kamada، نويسنده , , Susumu and Okamoto، نويسنده , , Wataru and Hatano، نويسنده , , Tadashi and Tai، نويسنده , , RenZhong and Kagoshima، نويسنده , , Yasushi، نويسنده ,
Abstract :
A novel approximation for calculating the first-order spatial coherence of undulator radiation is presented. Since the far-field approximation is not used in the calculation, it is applicable even in the near-field region. Compared with numerical results based on the first principles, the approximation is proved to be quite reasonable. The spatial coherence measured at the Photon Factory, KEK is analyzed using the formula and the results are found to be consistent with the design value within experimental errors.
Keywords :
Undulator , Van Cittert–Zernike theorem , emittance , spatial coherence
