Lattice Definitions

The APS PAR lattice consists of 2 superperiods, 2 quadrants per superperiod. The magnets are powered in series by families. There are 8 dipoles (BM) and 16 focussing quads (QF). Defocusing is provided by the wedge effect of the dipole magnets. The PAR has 2 focusing sextupole (SF) and 8 defocusing sextupole (SD and S1) for chramaticity corrections. S1 sextupoles are not used currently. Orbit correction is performed using 10 horizontal and 10 vertical correctors. The sextupoles and correctors are implemented in 10 combination magnets each contain a sextupole, a vertical corrector and a horizontal corrector. Trim coils of the dipoles magnets are also available for orbit corrections in horizontal plane. Injection is achieved through two injection kickers located 180 degrees apart in betatron phase. Extraction uses the same injection kickers and a dedicated extraction kicker. A septum magnet serves both injection and extraction. PAR has two normal conducting cavities located in the straight section opposit to the injection section. The fundamental RF cavity captures the injected bunches into a single bunch and the harmonic RF cavity is turned on later in the cycle to compress the bunch to 0.3 ns in length. The current operations PAR lattice has a 4 mm DC orbit bump in the septum, which reduces the requirement on kicker pulse amplitudes. Because of that beam parameters are slightly different than the official design lattice. The links listed below give the full lattice definitions in MAD format for the PAR operations and design lattice. The two figure below shows Twiss functions of full PAR lattices. The final figure shows the PAR layout.

• Full lattice description for the operational lattice with orbit bump (elegant input file)

• Full lattice description for the ``original design'' lattice (elegant input file)

Figure 1: Twiss parameters for the operational lattice.

Figure 2: Twiss parameters for the ``original design'' lattice.

Figure 3: PAR layout