160 MeV H- injection into the CERN PSB
The H- beam from the proposed LINAC4 will be injected into the four existing rings of the PS Booster at 160 MeV. A substantial upgrade of the injection region is required, including the modification of the beam distribution system and the construction of a new H- injection system. This paper discusses beam dynamics and hardware requirements and presents the results of optimisation studies of the injection process for different beam characteristics and scenarios. The resulting conceptual design of the injection region is presented, together with the main hardware modifications and performance specifications.
Simulation of the CERN PS booster performance with 160 MeV H- injection from LINAC4
The ultimate luminosity (2.3 x 1034 cm-2 s-1) in the LHC can only be reached or even exceeded if a major upgrade of the CERN proton injector complex takes place. The first identified bottleneck towards higher brightness beams is the 50 MeV proton injection of Linac2 into the PS booster (PSB). Doubling the intensity in the PSB can be achieved with a new linac (Linac4), which increases the injection energy to 160 MeV. Linac4 will provide H- ions and use charge-exchange injection into the PSB instead of the present multi-turn injection. We present the current status of simulations with ACCSIM, ORBIT, and ESME for all three planes. We use different initial distributions, compare the results of ACCSIM and ORBIT and highlight their differences.
ARRESTS AMONG HOMELESS AND RUNAWAY YOUTHS: THE EFFECTS OF RACE AND GENDER
ABSTRACT This study examined the contributions of race and gender to the likelihood of a first post-run arrest for a more serious and less serious offense in a sample of homeless and runaway youths from four Midwestern states. Event history analysis was used to test the hypothesis that race and gender would interact so that the likelihood of a first post-run arrest for a more serious and less serious offense would be highest for non-white males and non-white females, respectively. Potentially confounding factors—deviant subsistence strategies, substance use, gang involvement and membership, prior arrests, age, prior physical abuse, age on own, and spending time on the street—were controlled in the analyses. The hypotheses regarding the interaction of race and gender were not supported by the data. Non-whites were more likely than whites, and males were more likely than females, to be arrested for a more serious offense, and white females were more likely than non-white females to be arrested for a less serious offense.