A ug 2 00 5 The ATLAS Pixel Detector
The ATLAS Pixel Detector is the innermost layer of the ATLAS tracking system and will contribute significantly to the ATLAS track and vertex reconstruction. The detector consists of identical modules, arranged in three barrels concentric wi th the beam line and centered on the interaction point and three dis ks on either side for the forward region. The position of the Pixel Detector near the interaction point requires excellent radiation hardness, mechanical and the rmal robustness and good long-term stability, all combined witha low material budget. The detector layout, results from production modules and the status of assembly are presented.
MCC: The Module Controller Chip for the ATLAS pixel detector
In this article we describe the architecture of the Module Controller Chip for the ATLAS Pixel Detector. The project started in 1997 with the definition of the system specifications. A first fully-working rad-soft prototype was designed in 1998, while a radiation hard version was submitted in 2000. The 1998 version was used to build pixel detector modules. Results from those modules and from the simulated performance in ATLAS are reported. In the article we also describe the hardware/software tools developed to test the MCC performance at the LHC event rate.
To Devolve or Not To Devolve? Welfare Reform in the States
This article analyzes variation in the degree to which states have responded to the devolution of welfare at the federal level by devolving authority over welfare policy to local government. I find that to the extent that states have devolved authority to lower levels of government, they tend to be states that already had a high degree of involvement of local government in welfare provision. In states without this record of local government involvement, the devolution that has occurred has not generated greater involvement of local government, but rather responsibility has been devolved to regional entities with ties to workforce development and with a substantial degree of business involvement. As states gain increasing authority over a redistributive policy, they may begin to treat it as a subset of a larger developmental policy—workforce development.