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Status of the Control Sytem for the Front-End of the Spallation Neutron Source  [PDF]
S. A. Lewis,C. A. Lionberger,P. T. Cull
Physics , 2001,
Abstract: The Spallation Neutron Source (SNS) is a partnership between six laboratories. To ensure a truly integrated control system, many standards have been agreed upon, including the use of EPICS as the basic toolkit. However, unique within the partnership is the requirement for Lawrence Berkeley National Lab, responsible for constructing the Front End, to operate it locally before shipping it to the Oak Ridge National Lab (ORNL) site. Thus, its control system must be finished in 2001, well before the SNS completion date of 2006. Consequently many decisions regarding interface hardware, operator screen layout, equipment types, and so forth had to be made before the other five partners had completed their designs. In some cases the Front-End has defined a standard by default; in others an upgrade to a new standard is anticipated by ORNL later. Nearly all Front-End devices have been commissioned with the EPICS control system. Of the approximately 1500 signals required, about 60% are now under daily operational use. The control system is based on "standard architecture"; however, it has a field-bus dominated layout. This paper will discuss some unique interface requirements that led to adding new device families into the EPICS repertoire. It will also describe the choices and trade-offs made for all major areas.
The BTeV RICH Front End Electronics  [PDF]
Marina Artuso
Physics , 2005, DOI: 10.1016/j.nima.2005.08.021
Abstract: We report on the design and testing of novel mixed analog and digital front end ASICs custom made for the single photon detectors considered for the BTeV RICH system. The key features are reviewed, as well as results achieved using electronics bench tests and beam studies.
Status of the warm front end of PXIE  [PDF]
A. Shemyakin,M. Alvarez,R. Andrews,C. Baffes,A. Chen,B. Hanna,L. Prost,G. Saewert,V. Scarpine,J. Steimel,D. Sun,D. Li,R. D'Arcy
Physics , 2015,
Abstract: A CW-compatible, pulsed H- superconducting linac is envisaged as a possible path for upgrading Fermilab's injection complex. To validate the concept of the front- end of such a machine, a test accelerator (a.k.a. PXIE) is under construction. The warm part of this accelerator comprises a 10 mA DC, 30 keV H- ion source, a 2m-long LEBT, a 2.1 MeV CW RFQ, and a 10-m long MEBT that is capable of creating a large variety of bunch structures. The paper will report commissioning results of a partially assembled LEBT, status of RFQ manufacturing, and describe development of the MEBT, in particular, of elements of its chopping system.
Muon capture for the front end of a muon collider  [PDF]
D. Neuffer,C. Yoshikawa
Physics , 2012,
Abstract: We discuss the design of the muon capture front end for a \mu+-\mu- Collider. In the front end, a proton bunch on a target creates secondary pions that drift into a capture transport channel, decaying into muons. A sequence of rf cavities forms the resulting muon beams into strings of bunches of differing energies, aligns the bunches to (nearly) equal central energies, and initiates ionization cooling. The muons are then cooled and accelerated to high energy into a storage ring for high-energy high luminosity collisions. Our initial design is based on the somewhat similar front end of the International Design Study (IDS) neutrino factory.
Chaotic Behavior in Receiver Front-End Limiters
Fran ois Caudron;Achour Ouslimani;Rene Vezinet;Abed-elhak Kasbari
PIER Letters , 2011, DOI: 10.2528/PIERL11020305
Abstract: A delay nonlinear differential equation is proposed to investigate the condition of the microwave chaotic behavior existing between the antenna and the front-end protection circuit of a receiver such as the radar front-end limiter circuit. This investigation concerns the case of intentional or unintentional signals applied to the antenna outside of its bandwidth. Bifurcation diagrams show that the chaotic behavior appears for antenna impedance up to 10 Ω and for amplitudes greater than 1.2 V. Electrical simulation results agree well with theoretical ones.
Front-end Electronics for the CALICE/EUDET Calorimeters  [PDF]
Remi Cornat
Physics , 2009,
Abstract: The CALICE collaboration is involved in the design of compact calorimeters featuring a high granularity. The technical developments have to overcome various design issues such as the power dissipation, the integration of the front-end electronics inside the detector and connections between the parts. A huge collaborative work is required to achieve the devices using common tools and designs.
Muon capture in the front end of the IDS neutrino factory  [PDF]
D. Neuffer,M. Martini,G. Prior,C. Rogers,C. Yoshikawa
Physics , 2012,
Abstract: We discuss the design of the muon capture front end of the neutrino factory International Design Study. In the front end, a proton bunch on a target creates secondary pions that drift into a capture transport channel, decaying into muons. A sequence of rf cavities forms the resulting muon beams into strings of bunches of differing energies, aligns the bunches to (nearly) equal central energies, and initiates ionization cooling. The muons are then accelerated to high energy where their decays provide neutrino beams. For the International Design Study (IDS), a baseline design must be developed and optimized for an engineering and cost study. We present a baseline design that can be used to establish the scope of a future neutrino Factory facility.
Electromagnetic Interference Impact on Front-End Receivers Outside the Antenna Bandwidth
Fran ois Caudron;Achour Ouslimani;Rene Vezinet;Abed-elhak Kasbari
PIER B , 2012, DOI: 10.2528/PIERB11111004
Abstract: Impact of electromagnetic interference on front-end receiver behaviour is theoretically and experimentally studied outside the bandwidth of the antennas. Microwave chaotic generation is observed. Under certain conditions, reflected waves combined to the non linearity of the front-end receiver leads to a chaotic signal generation between the antenna and the front-end receiver. Different antennas, such as patch, loop, monopole and horn, are tested. Theoretical and experimental results are presented for each antenna.
A Subband-Based SVM Front-End for Robust ASR  [PDF]
Jibran Yousafzai,Zoran Cvetkovic,Peter Sollich,Matthew Ager
Computer Science , 2013,
Abstract: This work proposes a novel support vector machine (SVM) based robust automatic speech recognition (ASR) front-end that operates on an ensemble of the subband components of high-dimensional acoustic waveforms. The key issues of selecting the appropriate SVM kernels for classification in frequency subbands and the combination of individual subband classifiers using ensemble methods are addressed. The proposed front-end is compared with state-of-the-art ASR front-ends in terms of robustness to additive noise and linear filtering. Experiments performed on the TIMIT phoneme classification task demonstrate the benefits of the proposed subband based SVM front-end: it outperforms the standard cepstral front-end in the presence of noise and linear filtering for signal-to-noise ratio (SNR) below 12-dB. A combination of the proposed front-end with a conventional front-end such as MFCC yields further improvements over the individual front ends across the full range of noise levels.
Front-End electronics configuration system for CMS  [PDF]
P. Gras,F. Drouhin,W. Funk,L. Gross,D. Vintache
Physics , 2001,
Abstract: The four LHC experiments at CERN have decided to use a commercial SCADA (Supervisory Control And Data Acquisition) product for the supervision of their DCS (Detector Control System). The selected SCADA, which is therefore used for the CMS DCS, is PVSS II from the company ETM. This SCADA has its own database, which is suitable for storing conventional controls data such as voltages, temperatures and pressures. In addition, calibration data and FE (Front-End) electronics configuration need to be stored. The amount of these data is too large to be stored in the SCADA database [1]. Therefore an external database will be used for managing such data. However, this database should be completely integrated into the SCADA framework, it should be accessible from the SCADA and the SCADA features, e.g. alarming, logging should be benefited from. For prototyping, Oracle 8i was selected as the external database manager. The development of the control system for calibration constants and FE electronics configuration has been done in close collaboration with the CMS tracker group and JCOP (Joint COntrols Project)(1). (1)The four LHC experiments and the CERN IT/CO group has merged their efforts to build the experiments controls systems and set up the JCOP at the end of December, 1997 for this purpose.
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