Effects of accelerated crucible rotation on segregation and interface morphology for vertical Bridgman crystal growth: Visualization and simulation
Abstract The effects of accelerated crucible rotation technique (ACRT) on the segregation, interface shape, and morphological instability during vertical Bridgman (VB) crystal growth of succinonitrile (SCN) containing 0.064 wt% acetone were investigated by visualization experiments and computer simulation. It was found that ACRT was effective in reducing time-averaged constitutional supercooling and thus the morphological instability. However, at low rotation amplitudes, the morphology was less stable and the breakdown area was found to be wider as a result of flow transition. The simulated interface shapes were in good agreement with the observed ones. In addition, the onset of morphological breakdown was consistent with the numerical prediction based on the time-averaged constitutional supercooling.
Abstract A very promising spin physics programme will be soon on the way at the BNL Relativistic Heavy Ion Collider (RHIC). By studying the spin asymmetries for various processes (single photon, single jet and W ± production), we will compare the different predictions obtained using some sets of polarized parton distributions, available in the recent literature. We will put some emphasise on the analysis of the anticipated errors, given the event rates expected from this high luminosity new machine and the current acceptance for the detector systems at RHIC.