A novel, least invasive beam profile monitor based on a supersonic gas jet has been developed by the QUASAR Group at the Cockcroft Institute, UK. It allows the measurement of beam profiles for various particle beams across a range of energies and vacuum levels. A finely collimated neutral gas jet, produced by a nozzle and several skimmers, is injected into the vacuum chamber perpendicular to th...

Direct detector device (DDD) cameras have revolutionized single particle electron cryomicroscopy (cryo-EM). In addition to an improved camera detective quantum efficiency, acquisition of DDD movies allows for correction of movement of the specimen, due to both instabilities in the microscope specimen stage and electron beam-induced movement. Unlike specimen stage drift, beam-induced movement is...

The importance of nonlinear beam dynamics effects in synchrotron light sources is caused by strong demands on beam quality to obtain long lifetime, small emittance and stability. In this paper, the non-linear particle trajectory equation modifications are given, which simplify the single particle tracking simulation in storage ring using the Matlab environment [1]. The radiation damping times i...

A key element in the generation of optical torque in optical traps, which occurs when electromagnetic angular momentum is transferred from the trapping beam to the trapped particle by scattering, is the symmetries of the scattering particle and the trapping beam. We discuss the effect of such symmetries on the generation and measurement of optical torque in optical tweezers, and some consequent...

We compute the rapidity dependence of particle and transverse energy production in ultrarelativistic heavy ion collisions at various beam energies and atomic numbers using the perturbative QCD + saturation model. The distribution is a broad gaussian near y = 0 but the rapid increase of particle production with the beam energy will via energy conservation strongly constrain the rapidity distribu...

The alpha-particle emission spectrum in beam-injected (non-Maxwellian) deuterium-tritium (DT) burning plasma is examined by solving the Boltzmann-Fokker-Planck (BFP) equations for deuteron, triton and alpha-particle simultaneously. It is shown that owing to the existence of energetic component in fuel-ion energy distribution functions due to neutral-beam injection (NBI) and/or nuclear elastic s...

Every accelerator or storage ring system consists of a charged particle beam propagating through a beam line. Although a number of computer programs exist that simulate the propagation of a beam% a given beam line, only a few provide the capabilities for designing, commissioning and operating the beam line. This paper shows how a “multi-track” simulation and analysis code can be used for these ...

The nonlinear interaction of a tenuous continuous electron beam with a traveling electromagnetic wave in the cyclotron resonance laser accelerator is analyzed using a single-particle model and multi-particle simulation. It is found that the maximum beam energy gain and acceleration distance obey certain scaling laws for optimized systems, and that the maximum energy gain is limited primarily by...

The Manne Siegbahn Laboratory is planning for the transfer of the CRYRING synchrotron and storage ring to the future FAIR facility, where it will be used for deceleration of antiprotons and heavy ions at FLAIR. The efficiency of the deceleration process, i.e. the minimization of particle losses, is important, and we show here a strong correlation between losses during the start of the decelerat...

Results on strange particle production in Pb-Pb collisions at 158 and 40 A GeV/c beam momentum from the NA57 experiment at CERN SPS are presented. Particle yields and ratios are compared with those measured at RHIC. Strangeness enhancements with respect to p-Be reactions at the same beam momenta have been also measured: results about their dependence on centrality and collision energy are repor...