Readout System for the CMS RPC Muon Trigger
The CMS detector contains the RPC chambersa dedicated trigger subdetectorto identify muons, measure their transverse momenta pT, and determine the bunch crossing from which they originated.The RPC Muon Trigger algorithm is based on muon track search and classification in raw data from the RPC chambers. Large part of the RPC trigger electronics will reside in the control room (approx. 90 meters from the detector) where all trigger data are concentrated. Dedicated synchronous compression decompression algorithm is needed to sent all data for each bunch crossing via optical links. The RPC Readout system uses the same data as Trigger system and will be placed in the Trigger Racks. The idea of readout system and its limitations are discussed below. The paper includes description of prototype boards and tests in the synchronous CERN LHC like test beam H2 in May 2000.
Resistive Plate Chamber (RPC) based Muon Trigger System for the CMS experiment – PAttern Comparator ASIC
Abstract The CMS detector will have a dedicated subdetector (RPC chambers) to identify muons, measure their transverse momenta pt, and determine the bunch crossings from which they originate. The trigger algorithm is based on muon track search and classification in raw data from the RPC chambers grouped in the four muon stations in the CMS magnet yoke. The PAttern Comparator (PCA) ASIC will search for tracks of muons and measure their momenta. The idea of PAC and its first prototype implementation are shown here.
Negatively charged phospholipids trigger the interaction of a bacterial Tat substrate precursor protein with lipid monolayers.
Folded proteins can be translocated across biological membranes via the Tat machinery. It has been shown in vitro that these Tat substrates can interact with membranes prior to translocation. Here we report a monolayer and infrared reflection-absorption spectroscopic (IRRAS) study of the initial states of this membrane interaction, the binding to a lipid monolayer at the air/water interface serving as a model for half of a biological membrane. Using the model Tat substrate HiPIP (high potential iron-sulfur protein) from Allochromatium vinosum, we found that the precursor preferentially interacts with monolayers of negatively charged phospholipids. The signal peptide is essential for the interaction of the precursor protein with the monolayer because the mature HiPIP protein showed no interaction with the lipid monolayer. However, the individual signal peptide interacted differently with the monolayer compared to the complete precursor protein. IRRA spectroscopy indicated that the individual signal peptide forms mainly aggregated β-sheet structures. This β-sheet formation did not occur for the signal peptide when being part of the full length precursor. In this case it adopted an α-helical structure upon membrane insertion. The importance of the signal peptide and the mature domain for the membrane interaction is discussed in terms of current ideas of Tat substrate-membrane interactions.