3,016 research outputs found
A 3-D Track-Finding Processor for the CMS Level-1 Muon Trigger
We report on the design and test results of a prototype processor for the CMS
Level-1 trigger that performs 3-D track reconstruction and measurement from
data recorded by the cathode strip chambers of the endcap muon system. The
tracking algorithms are written in C++ using a class library we developed that
facilitates automatic conversion to Verilog. The code is synthesized into
firmware for field-programmable gate-arrays from the Xilinx Virtex-II series. A
second-generation prototype has been developed and is currently under test. It
performs regional track-finding in a 60 degree azimuthal sector and accepts 3
GB/s of input data synchronously with the 40 MHz beam crossing frequency. The
latency of the track-finding algorithms is expected to be 250 ns, including
geometrical alignment correction of incoming track segments and a final
momentum assignment based on the muon trajectory in the non-uniform magnetic
field in the CMS endcaps.Comment: 7 pages, 5 figures, proceedings for the conference on Computing in
High Energy and Nuclear Physics, March 24-28 2003, La Jolla, Californi
Approximate computation of an eigenwave from measurements of its amplitudes at a given point
Under the assumption that the variables in the wave equation can be separated and its coefficients are periodic, we develop a classification of seismic eigenwaves and use it to answer some questions as to how to specify the type and basic parameters of a wave on the basis of measurements of amplitudes, whether there exist points of chaos, and how to predict them. © 2014 Pleiades Publishing, Ltd
2D shallow seismic study of terrigenous heavy oil reservoir driven by SAGD at the Ashalchy Oil Field, Tatarstan
The objective of seismic experiments was to estimate possibilities of shallow seismic in control of SAGD recovery process under geological conditions of the South Tatar arch. Bituminous sandstone member Ufimian time (P2ss) is the productive formation of Ashalchy heavy oil field. Seismic acquisition, data processing and results obtained at north-west dome heavy oil field are presented in this paper. Thermal field established in reservoir driven by SAGD has complicated distribution. It was found that steam chambers were mapped by low values of interval velocity and bright spot dynamic anomalies. Distribution of anomalies along seismic profiles let make an assumption that size and temperature of steam chamber are controlled by effective porosity of surrounding formation and integrity overlying seal. Dense rocks are observed around high temperature chamber. Dynamic anomalies are conditioned by hydrocarbon gas and hydrogen disulfide let out from heated heavy oil. Gas products accumulate at the reservoir top and also above low temperature chambers forming gas cap. The results obtained allow to recommend shallow seismic for monitoring steam chamber's dimensions in terrigenous reservoir within Cheremshan-Barstrick group of heavy oil fields
2D shallow seismic study of heated by steam flooding heavy oil reservoir of Ashalchinskoye field
The aim of executed seismic experiments was to estimate a possibilities of shallow seismic in data support of heavy oil recovery process like steam assisted gravity drainage (SAGD), in particular a localization of steam chamber under geological conditions within the western slope of the South Tatar arch. Seismic acquisition, peculiarity of data processing and results received at Ashalchinskoye heavy oil field, are presented in this article. It was found that steam chambers within seismic survey area were mapped by low values of interval velocity Developed shallow seismic technology make it possible to delineate zones with decreased bitumen viscosity because of heat carrier injection in terrigenous reservoir (steam chambers) and get information about possible geologic causes of steady temperature regimes in productive formation
The Track-Finding Processor for the Level-1 Trigger of the CMS Endcap Muon System
We report on the development and test of a prototype track-finding processor for the level-1 trigger of the CMS endcap muon system. The processor links track segments identified in the cathode strip chambers of the endcap muon system into complete three-dimensional tracks, and measures the transverse momentum of the best track candidates from the sagitta induced by the magnetic bending. The algorithms are implemented using SRAM and Xilinx Virtex FPGAs, and the measured latency is 15 clocks. We also report on the design of the pre-production prototype, which achieves further latency and size reduction using state-of-the-art technology. (4 refs)
A novel application of Fiber Bragg Grating (FBG) sensors in MPGD
We present a novel application of Fiber Bragg Grating (FBG) sensors in the
construction and characterisation of Micro Pattern Gaseous Detector (MPGD),
with particular attention to the realisation of the largest triple (Gas
electron Multiplier) GEM chambers so far operated, the GE1/1 chambers of the
CMS experiment at LHC. The GE1/1 CMS project consists of 144 GEM chambers of
about 0.5 m2 active area each, employing three GEM foils per chamber, to be
installed in the forward region of the CMS endcap during the long shutdown of
LHC in 2108-2019. The large active area of each GE1/1 chamber consists of GEM
foils that are mechanically stretched in order to secure their flatness and the
consequent uniform performance of the GE1/1 chamber across its whole active
surface. So far FBGs have been used in high energy physics mainly as high
precision positioning and re-positioning sensors and as low cost, easy to
mount, low space consuming temperature sensors. FBGs are also commonly used for
very precise strain measurements in material studies. In this work we present a
novel use of FBGs as flatness and mechanical tensioning sensors applied to the
wide GEM foils of the GE1/1 chambers. A network of FBG sensors have been used
to determine the optimal mechanical tension applied and to characterise the
mechanical tension that should be applied to the foils. We discuss the results
of the test done on a full-sized GE1/1 final prototype, the studies done to
fully characterise the GEM material, how this information was used to define a
standard assembly procedure and possible future developments.Comment: 4 pages, 4 figures, presented by Luigi Benussi at MPGD 2015 (Trieste,
Italy). arXiv admin note: text overlap with arXiv:1512.0848
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