Search results for "detector"
showing 10 items of 3491 documents
Solid-phase extraction disks for determining pesticides from soil leachates
1997
Abstract Analytical techniques are essential for identifying and quantifying the chemicals present in environmental samples. A method for extracting pesticides from soil leachates was developed. The proposed method is based on solid-phase extraction and uses 47-mm disks of octyl-bonded silica. Analysis was carried out by gas chromatography with nitrogen–phosphorus and electron-capture detectors. Several factors that can provide better pesticide recoveries with this extraction method are discussed. These factors are: the kind and percentage of organic solvent used in the extraction procedure, the volume and the ionic strength (adding 15% of NaCl) of the aqueous phase which passes through the…
Signal to Noise Ratio of Silicon Photomultipliers measured in the Continuous Wave Regime
2014
We performed a Signal to Noise Ratio characterization, in the continuous wave regime, at different bias voltages, frequencies and temperatures, on a novel class of silicon photomultipliers fabricated in planar technology on silicon p-type substrate. Signal to Noise Ratio has been measured as the ratio of the photogenerated current, filtered and averaged by a lock-in amplifier, and the Root Mean Square deviation of the overall current flowing to the device. The measured noise takes into account the shot noise, resulting from the photocurrent and the dark current. We have also performed a comparison between our SiPMs and a photomultiplier tube in terms of Signal to Noise Ratio, as a function …
SEARCHES FOR POINT-LIKE AND EXTENDED NEUTRINO SOURCES CLOSE TO THE GALACTIC CENTER USING THE ANTARES NEUTRINO TELESCOPE
2014
A search for cosmic neutrino sources using six years of data collected by the ANTARES neutrino telescope has been performed. Clusters of muon neutrinos over the expected atmospheric background have been looked for. No clear signal has been found. The most signal-like accumulation of events is located at equatorial coordinates R.A. = -46º.8 and decl. = -64º.9 and corresponds to a 2.2 sigma background fluctuation. In addition, upper limits on the flux normalization of an E-2 muon neutrino energy spectrum have been set for 50 pre-selected astrophysical objects. Finally, motivated by an accumulation of seven events relatively close to the Galactic Center in the recently reported neutrino sample…
Performance of the Advanced GAmma Tracking Array at GANIL
2020
The performance of the Advanced GAmma Tracking Array (AGATA) at GANIL is discussed, on the basis of the analysis of source and in-beam data taken with up to 30 segmented crystals. Data processing is described in detail. The performance of individual detectors are shown. The efficiency of the individual detectors as well as the efficiency after $\gamma$-ray tracking are discussed. Recent developments of $\gamma$-ray tracking are also presented. The experimentally achieved peak-to-total is compared with simulations showing the impact of back-scattered $\gamma$ rays on the peak-to-total in a $\gamma$-ray tracking array. An estimate of the achieved position resolution using the Doppler broadeni…
Large area strip edgeless detectors fabricated by plasma etching process
2007
This work presents the last results from large area edgeless detector, fabricated by Plasma Etching Process to reduce the conventional width of the terminating structure of position sensitive detectors to the detector rim.. A current terminating ring is used to decouple the electrical behavior of the surface from the sensitive volume within a few tens of micrometers. The detectors have been illuminated using an infrared laser and their surface scanned in order to understand their collection behavior at the cut edge. The detectors have very high efficiency up to the insensitive area which is located about 60 mum from the detector edge.
Measurements of the stopping forces for heavy ions in Ge, Ag and Au using novel ‘polka-dot’ detectors
2006
Measurements of the stopping forces for C-14, N-14 and O-16 ions in Ge and Au, for N-14 and F-19 ions in Ag, as well as for F-19 ions in Au have been made, respectively. A novel technique, reported recently, using PIN diodes coated directly with the stopping medium in a polka dot pattern was used. This provided a set of precise, self-consistent measurements on the same stopping medium. Results show small but significant deviations from SRIM stopping predictions and are also compared to a recently-developed empirical stopping force predictor.
Hard probes in heavy ion collisions at the lhc: pdfs, shadowing and pa collisions
2003
This manuscript is the outcome of the subgroup ``PDFs, shadowing and $pA$ collisions'' from the CERN workshop ``Hard Probes in Heavy Ion Collisions at the LHC''. In addition to the experimental parameters for $pA$ collisions at the LHC, the issues discussed are factorization in nuclear collisions, nuclear parton distributions (nPDFs), hard probes as the benchmark tests of factorization in $pA$ collisions at the LHC, and semi-hard probes as observables with potentially large nuclear effects. Also, novel QCD phenomena in $pA$ collisions at the LHC are considered. The importance of the $pA$ program at the LHC is emphasized.
High Energy Nuclear Collisions
1999
Highlights of the results from ultrarelativistic heavy ion collisions at CERN-SPS are reviewed. In particular, I discuss how the experimental results indicate that a collective strongly interacting system has been produced, and what are the implications towards the Quark Gluon Plasma. The physical ideas behind measuring certain observables are introduced. The future program of high energy nuclear collisions at BNL-RHIC and CERN-LHC/ALICE is also briefly discussed.
Searching for Axion Dark Matter in Atoms: ~Oscillating Electric Dipole Moments and Spin-Precession Effects
2015
Roberts, Benjamin M. "Searching for Axion Dark Matter in Atoms: ~Oscillating Electric Dipole Moments and Spin-Precession Effects" in Proceedings, 11th Patras Workshop on Axions, WIMPs and WISPs (Axion-WIMP 2015) / Irastorza, Igor G., Redondo, Javier, Carmona, José Manuel, Cebrian, Susana, Dafni, Theopisti, Iguaz, Francisco J., Luzon, Gloria (eds.), Verlag Deutsches Elektronen-Synchrotron : 2015 ; AXION-WIMP 2015 : 11th Patras Workshop on Axions, WIMPs and WISPs, 2015-06-22 - 2015-06-26, Zaragoza 11th Patras Workshop on Axions, WIMPs and WISPs, AXION-WIMP 2015, Zaragoza, Spain, 22 Jun 2015 - 26 Jun 2015 ; DESY-PROC 120-123(2015). doi:10.3204/DESY-PROC-2015-02/roberts_benjamin_axions
Real-time measurements of solar $pp$ neutrinos using $^{131}$Xe
2020
Various large-scale experiments for double beta decay or dark matter are based on xenon. Current experiments are on the tonne scale but there are also ideas to aim for even larger sizes in the future. Here we study the potential of the isotope $^{131}$Xe to allow to make real-time measurements of solar $pp$ neutrinos, besides classical neutrino-electron scattering. Improved nuclear models are used to determine the cross-section of neutrinos on $^{131}$Xe. The present calculations deviate significantly from the previous ones due to updated estimates for the excited-state contributions. The updated capture-rate estimate for $pp$ neutrinos is $(4.47\pm 0.09)\ \rm SNU$ and for all solar neutrin…