Recent astrophysical and terrestrial experiments have motivated the proposal of a dark sector with GeV-scale gauge boson force carriers and new Higgs bosons. We present a search for a dark Higgs ...boson using 516 fb(-1) of data collected with the BABAR detector. We do not observe a significant signal and we set 90% confidence level upper limits on the product of the standard model-dark-sector mixing angle and the dark-sector coupling constant.
The existing muon detectors for high-energy physics experiments are mainly made of gas chambers such as Resistive Plate Chambers, Limited Streamer Tubes or Multi Wire Proportional Chambers. With the ...increasing luminosity of the new accelerators and the increment in dimensions of the experiments the development of a new detection technique, which is robust, cheap and capable to sustain high particle rate, is mandatory. We present the technology proposed for the Super B muon system. The detector is based on MINOS style extruded scintillators coupled to wavelength shifting fibers. The light readout is done by means of Silicon Photomultiplier devices. We report the R&D results on prototypes that can be operated either with binary readout, measuring only one coordinate, or with a TDC readout that can measure both the coordinate at the same time with adequate precision. Efficiency and time resolution will be discussed for different prototype geometry as well as the main operational issues related to the photodetectors, like stability, noise rate and neutron damage. A full-scale prototype with the same geometry designed for the SuperB experiment is under construction in our lab and it will be tested with a muon/pion beam at FNAL next fall. The structure optimization has been studied using a GEANT4 Monte Carlo simulation and the expected muon identification performances have been evaluated with a neural network algorithm, we present preliminary results of the optimization and its implication for the SuperB muon system.
Using the grid for the BaBar experiment Bozzi, C.; Adye, T.; Andreotti, D. ...
IEEE transactions on nuclear science,
10/2004, Letnik:
51, Številka:
5
Journal Article
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The BaBar experiment has been taking data since 1999. In 2001 the computing group started to evaluate the possibility to evolve toward a distributed computing model in a grid environment. We built a ...prototype system, based on the European Data Grid (EDG), to submit full-scale analysis and Monte Carlo simulation jobs. Computing elements, storage elements, and worker nodes have been installed at SLAC and at various European sites. A BaBar virtual organization (VO) and a test replica catalog (RC) are maintained in Manchester, U.K., and the experiment is using three EDG testbed resource brokers in the U.K. and in Italy. First analysis tests were performed under the assumption that a standard BaBar software release was available at the grid target sites, using RC to register information about the executable and the produced n-tuples. Hundreds of analysis jobs accessing either Objectivity or Root data files ran on the grid. We tested the Monte Carlo production using a farm of the INFN-grid testbed customized to install an Objectivity database and run BaBar simulation software. First simulation production tests were performed using standard Job Description Language commands and the output files were written on the closest storage element. A package that can be officially distributed to grid sites not specifically customized for BaBar has been prepared. We are studying the possibility to add a user friendly interface to access grid services for BaBar.
This paper discusses the use of e-science grid in providing computational resources for modern international high energy physics (HEP) experiments. We investigate the suitability of the current ...generation of grid software to provide the necessary resources to perform large-scale simulation of the experiment and analysis of data in the context of multinational collaboration.
SuperB is a super-flavor factory that will be built in Tor Vergata (Italy). The project, recently approved by the Italian Government, and classified as the flagship project of the Italian INFN, foresees ...the construction of a high intensity asymmetric electron-positron collider and of the related detector. The expected luminosity of 2x1036cm−2 s−1, a factor 100 higher than the last generation of B-factories, will allow the high statistic study of rare decays and, possibly, will allow a deeper insight in the field of new physics. Part of the SuperB apparatus is the Instrumented Flux Return (IFR). This detector exploits the flux return iron structure of the superconducting solenoid as absorber for the identification of muons and neutral hadrons. In more details, It consists of ≃ 92 cm of iron interleaved by 9 layers of highly segmented scintillators. The detection technique is based on relatively inexpensive extruded plastic scintillator bars produced at the FNAL-NICADD facility. The scintillation light is collected through Wave Length Shifting fibers and guided to recently developed devices called Silicon Photon Multipliers used as photodetectors. The use of plastic scintillator as active material ensures reliability, robustness and long term stability while the high granularity and the fast response guarantee a good space-time resolution, extremely important to cope with the expected high particles flux. The readout scheme under evaluation is this manuscript is the double coordinate readout (“BIRO readout”) where two layers of orthogonal scintillator bars provide both, the polar and azimuthal coordinate. In order to deeply understand the performances and possible drawbacks of the above technique, a full depth prototype has been designed and built in Ferrara and Padova, and tested at the Fermilab Test Beam Facility (FBTF) in December 2010. In this paper a comprehensive description of the IFR related R&D studies will be presented. In particular, we will focus on the results of the Fermilab beam test, issues and future activities will also be outlined.
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