266 research outputs found
Correction of vertical dispersion and betatron coupling for the CLIC damping ring
The sensitivity of the CLIC damping ring to various kinds of alignment errors has been studied. Without any correction, fairly small vertical misalignments of the quadrupoles and, in particular, the sextupoles, introduce unacceptable distortions of the closed orbit as well as intolerable spurious vertical dispersion and coupling due to the strong focusing optics of the damping ring. A sophisticated beam-based correction scheme has been developed to bring the design target emittances and the dynamic aperture back to the ideal value. The correction using dipolar correctors and several skew quadrupole correctors allows a minimization of the closed-orbit distortion, the cross-talk between vertical and horizontal closed orbits, the residual vertical dispersion and the betatron coupling
Luminosity Tuning at the Interaction Point
Minimisation of the emittance in a linear collider is not enough to achieve optimal performance. For optimisation of the luminosity, tuning of collision parameters such as angle, offset, waist, etc. is needed, and a fast and reliable tuning signal is required. In this paper tuning knobs are presented, and their optimisation using beamstrahlung as a tuning signal is studied
Minimizing Emittance for the CLIC Damping Ring
The CLIC damping rings aim at unprecedented small normalized equilibrium emittances of 3.3 nm vertical and 550 nm horizontal, for a bunch charge of 2.6·109 particles and an energy of 2.4 GeV. In this parameter regime the dominant emittance growth mechanism is intra-beam scattering. Intense synchrotron radiation damping from wigglers is required to counteract its effect. Here the overall optimization of the wiggler parameters is described, taking into account state-of-the-art wiggler technologies, wiggler effects on dynamic aperture, and problems of wiggler radiation absorption. Two technical solutions, one based on superconducting magnet technology the other on permanent magnets are presented. Although dynamic aperture and tolerances of this ring design remain challenging, benefits are obtained from the strong damping. For optimized wigglers, only bunches for a single machine pulse may need to be stored, making injection/extraction particularly simple and limiting the synchrotron-radiation power. With a 365 m circumference the ring remains comparatively small
Inclusion of beta-carotene in various courses of chemotherapy of lympholeucosis L1210
Possibility of including of synthetic beta-carotene in variuos courses of chemotherapy of lympholeucosis of mice BDF1 was investigated. In experimental models cyclophosphan and platidiam (50, 100, 200 and 8 mg/kg b.w. respectively) was used as anticancer drugs. Beta-carotene (5, 10, 20, 50 mg/kg b.w.) was administrated to mice in different schemes. During experiments it was observed that beta-carotene does not effect the rapeutic action of cyclophósphan and platidiam during treatment of lympholeucosis L1210
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