109912783
ICARUS 600 ton: A status report
The goal of the ICARUS Project is the installation of a multi-kiloton LAr TPC in the underground Gran Sasso Laboratory. The programme foresees the realization of the detector in a modular way. The first step is the construction of a 600 ton module which is now at an advanced phase. It will be mounted and tested in Pavia in one year and then it will be moved to Gran Sasso for the final operation. The major cryogenic and purification systems and the mechanical components of the detector have been constructed and tested in a 10 m3 prototype. The results of these tests are here summarized.
56470793
DESIGN OF BEAM TRANSPORT LINE FROM RCS TO TARGET FOR CSNS
China Spallation Neutron Source (CSNS) uses the high energy proton beam to strike the Tungsten target to generate neutrons through spallation reaction. The proton beam is extracted from the Rapid Cycling Synchrotron (RCS), whose beam power reaches 100 kW. For the sake of target lifetime, beam distribution at the target surface is required as uniform as possible. Nonlinear beam density redistribution method with two octupole magnets has been studied. Also some simulation and theoretical calculation have been done. According to the simulation result, the beam density at the target is optimized and the beam loss is under control.
124075894
General conditions for self-cancellation of geometric aberrations in a lattice structure
In this paper we will discuss the general conditions for self-cancellation of geometric aberrations in an uncoupled or even coupled lattice structure. The self-cancellation conditions show that - I transformer even noninterleaved multipoles is not necessary. We will also give two examples for sextupole case to specify the application.
55843797
LATTICE DESIGN FOR THE BEPCII STORAGE RING
BEPCII, the upgrading project of the BEPC, has been being designed with a luminosity of 10 33 cm -2 s -1 at the J/ψ energy. It still keeps the potential to provide beams as a synchrotron radiation (SR) facility. The storage rings for collision contain a positron and an electron ring and the ring for dedicated SR uses the outer parts of the two rings. To fit all the conditions either on beam or on space limit, lattices are carefully designed for both high energy physics and SR experiments with sufficient dynamic apertures and high efficiencies for injection. The features of the lattices are also discussed in the paper. 1 DESIGN REQUIREMENTS BEPCII is an upgrade project of the Beijing ElectronPositron Collider (BEPC), in which a new inner ring will be installed inside the old one. It will provide colliding beams with the center-of-mass energy from 1.0GeV×2 to 2.0GeV×2 and also the dedicated synchrotron radiation beam with 2.5 GeV. For the colliding beams the luminosity is optimized at 1.89 GeV with 1×10 33 cm -2 s -1 . For the dedicated synchrotron radiation beam, the current is 250 mA with an emittance as low as possible. There have been several beam-lines in the BEPC for the synchrotron radiation experiments, so the current bending magnets and insertion devices in the southern region have to be fixed at their present positions. In order to increase the average luminosity, the “topoff” injection scheme up to 1.89 GeV is adopted. This requires that the injection and collision optics must be the same. The main parameters are shown in Tables 1 and 2.
123594822
Transfer matrices of dipoles with bending radius variation
With the increasing demand of high brightness in light source, the uniform dipole can not meet the needs of low emittance, and thus the dipole with bending radius variation is introduced in this paper. The transfer matrix of a non-uniform dipole whose bending radius is linearly changed is chosen as an example and a very simple calculation formula of non-uniform dipole transfer matrices is given. The transfer matrices of some common profile non-uniform dipoles are also listed. The comparison of these transfer matrices and the matrices calculated with slices method verifies the numerical accuracy of this formula. This method can make the non-uniform beam dynamic problem simpler, very helpful for emittance research and lattice design with non-uniform dipoles.
60626146
ILC Reference Design Report: ILC Global Design Effort and World Wide Study
125301587
Study of the process $e^+ e^- \to \omega\pi^0 $ with the KLOE detector
Using $\sim$ 600 pb$^{-1}$ collected with the KLOE detector at DA$\Phi$NE, we have studied the production cross section of $\pi^+\pi^-\pi^0\pi^0$ and $\pi^0\pi^0\gamma$ final states in $e^+ e^-$ collisions at center of mass energies between 1000 and 1030 MeV. By fitting the observed interference pattern around $M_\phi$ for both final states, we extract a measurement (preliminary) for the ratio $\Gamma(\omega\to\pi^0\gamma)/\Gamma(\omega\to\pi^+\pi^-\pi^0) = 0.0934\pm 0.0022$. Since these two final states represent the 98% of the $\omega$ decay channels, we use unitarity to derive $BR(\omega\to\pi^+\pi^-\pi^0)= (89.94\pm 0.23)%$ and $BR(\omega\to\pi^0\gamma) = (8.40\pm 0.19)%$. % Moreover, the parameters describing the \eeto\wpc reaction around $M_\phi$ are used to extract the branching fraction for the OZI and G-parity violating $\phi\to\omega\pi^0$ decay: $BR(\phi\to\omega\pi^0) = (5.63\pm 0.70)\times 10^{-5}$.
118728331
KLOE measurement of the $\sigma(\pi^+ \pi^- (\gamma))$ cross section and the pi+ pi- contribution to the muon anomaly
125260045
Evidence of sigma particle in J / psi ---> omega pi pi
18889238
Studies of the vector meson mass generation scheme by chiral anomalies in two-dimensional nonAbelian gauge theories
Higher order effects of the two-dimensional non-Abelian gauge theories, in which the vector-meson mass is generated by chiral anomalies, will be studied. The $\beta$ function and the topological nature of the non-linear $\sigma$ model in the action and unitarity of the theory will be discussed.
110626236
Tests of MVD prototype pad detector with a β- source
Abstract The MVD group has been testing two versions of silicon pad detectors. One design uses a single metal layer for readout trace routing. The second type uses two layers of metal, allowing for greatly simplified signal routing. However, because the readout traces for the pads pass over the other pads in the same column (separated by an oxide layer), the double-metal design introduces crosstalk into the system. A simple test stand using a 90 Sr β − source with scintillator triggers was made to estimate the crosstalk. The crosstalk between pads in the same column of the pad detector was 1.6–3.1%. The values measured between pads in different columns were very close to zero. The measured crosstalk was below our maximum allowed value of 7.8%.