[en] This report deals with chromaticity correction in the TRISTAN phase I main ring version 11. The program PATRICIA is used to track the trajectories of test particles over 2000 turns. The results show that particles with transverse initial amplitudes of at least 11 σ in both planes and with a synchrotron oscillation amplitude of 7 σsub(e) remain stable. (author)

[en] The TRISTAN main ring now under construction has four insertions. Besides the normal modes in which the four insertions have the same optics, the TRISTAN main ring will be operated in somewhat more complicated configurations with insertions having different optics. This report will consider chromaticity corrections using six families of sextupoles for the TRISTAN main ring with two different insertion types; opposite insertions have the same optics. The strength of correcting sextupoles is determined mainly using the W-correction method. The program PATRICIA is used to track the trajectories of test particles over 800 turns. The results show that the correction scheme adopted allows adequately large amplitudes of betatron and synchrotron oscillations. (author)

[en] The author presents a prelimiary design of how a Tau Charm Factory could be added to the Beijing Electron Positron Collider (BEPC) facility. The design is offered independent of the issue of funding, which the facility would need outside help to accomplish. Included in the design are specifications for the storage rings, siting, and design goals

[en] General expressions of Ampere-Turns for superconducting dipole and quadrupole magnets based on sector coils are proposed. According to the magnetic field generated by simplified coil layouts using the line current theory, the required excitation current to achieve the desired field strength in the aperture is calculated. The contribution of magnetic field by an iron yoke is taken into account by using the image current method. The validity of derived equations is confirmed by applications to main superconducting magnets which have been built in several high energy accelerators. The proposed analytical expressions provide a simple relationship among the bore field, main dimensions of the magnet, and the total excitation current. These expressions are complementary to the existing method in the electromagnetic design, and are shown to be quite similar to those of conventional magnets. Finally, the comparison of Ampere-Turns between superconducting magnets and conventional magnets is presented

[en] A new idea to compensate the coupling of BEPC II will be introduced in this paper. The detector solenoid field in the interaction region will be compensated by six anti-solenoids which are located nearby the interaction point. Skew quadrupoles are adopted for the global coupling compensation. The coupling compensation scheme and the method to measure and tune the x-y coupling will be discussed in detail. (authors)

[en] Two multifunction superconducting magnets in the interaction region (IR) for Beijing electron positron collider upgrade project (BEPCII) have been measured in BESIII detector hall in 2007. Each superconducting magnet package contains multiple concentric layers with several function magnets called as a vertical focusing quadrupole (SCQ), a horizontal corrector (HDC/SCB), a vertical corrector (VDC), a skew quadrupole (SKQ) and three anti-solenoids (AS1, AS2 and AS3) to compensate the experimental detector solenoid field. All these function magnets SCQs, SCB/HDCs, VDCs and SKQs have been measured using two rotating coils. Their integral fields, their high order harmonics contents and the local fields along the beam line are obtained in detail with the rotating coil probe system. Comparing the results to the stretched wire, the differences for the integral fields are less than 0.2%. As a result, the method presented in this paper can be used as an absolute field measurement in our lab. - Highlights: → Absolute field measurements were realized, other calibration methods can be omitted.→ Multiple function harmonic coils were designed in order to simplify the coil design.→ A skew coil was added in the harmonic coil design.→ A short harmonic coil was used to scan the magnet end effect.

[en] BEPCII is a double ring e⁺e ^- collider with high beam currents and luminosity, so the high beam-related backgrounds may disturb the detector. In order to have a good quality of data taking, backgrounds should be kept at a level as low as possible. A series of collimators are designed and installed in both the e⁺ and e^- rings. Two of the collimators are horizontally movable, each for one ring, about 8 m upstream from the interaction point. Experiments have been done to identify the effectiveness of the movable collimators with different apertures and beam currents. The results show that the movable collimators are very effective and can reduce as much as about 50% of beam-related backgrounds. (authors)

[en] Superconducting interaction region (IR) magnets for Beijing Electron Positron Collider Upgrade Project (BEPC II) are used for increasing the BEPC II luminosity, correcting close orbit and coupling. These magnets are placed as close as possible to the interaction point (IP), immersed within the BES III detector solenoid field of 1.0 T. These magnets are designed into two magnet packages at each side of the IP with each contained inside a magnet cryostat.Each superconducting magnet package includes several function magnets of SCQ, SCB/HDC, VDC, SKQ and AS. Some of them, such as SCQ, SCB/HDC, VDC, SKQ were measured by rotating coil, and the integrals field and high order harmonic contents, local field along the beam line are known in details. Comparing these results with that from BNL which were measured inside the vertical Dewar, it's found that there were only small differences. Comparing with the results from the stretched wire, for SCQ and SCB as examples, it's found that the differences for the main fields are less than 3 x 10^-3. As a result, the method presented in the paper can be used for absolute magnetic field measurements. (authors)