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Author ANTARES Collaboration (Aguilar, J.A. et al); Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Salesa, F.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J.
Title Performance of the front-end electronics of the ANTARES neutrino telescope Type Journal Article
Year 2010 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 622 Issue 1 Pages 59-73
Keywords Neutrino telescope; Photomultiplier tube; Front-end electronics; ASIC
Abstract ANTARES is a high-energy neutrino telescope installed in the Mediterranean Sea at a depth of 2475 m. It consists of a three-dimensional array of optical modules, each containing a large photomultiplier tube. A total of 2700 front-end ASICs named analogue ring samplers (ARS) process the phototube signals, measure their arrival time, amplitude and shape as well as perform monitoring and calibration tasks. The ARS chip processes the analogue signals from the optical modules and converts information into digital data. All the information is transmitted to shore through further multiplexing electronics and an optical link. This paper describes the performance of the ARS chip: results from the functionality and characterization tests in the laboratory are summarized and the long-term performance in the apparatus is illustrated.
Address [Aguilar, J. A.; Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J. P.; Hernandez-Rey, J. J.; Mangano, S.; Salesa, F.; Toscano, S.; Yepes, H.; Zornoza, J. D.; Zuniga, J.] Univ Valencia, IFIC, CSIC, Valencia 46071, Spain, Email: s.loucatos@cea.fr
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes (up) ISI:000282530300009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 363
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Author SuperNEMO Collaboration (Argyriades, J. et al); Carcel, S.; Diaz, J.; Monrabal, F.; Serra, L.; Yahlali, N.
Title Results of the BiPo-1 prototype for radiopurity measurements for the SuperNEMO double beta decay source foils Type Journal Article
Year 2010 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 622 Issue 1 Pages 120-128
Keywords Double beta decay; NEMO-3; SuperNEMO; BiPo; Majorana neutrino; Radiopurity
Abstract The development of BiPo detectors is dedicated to the measurement of extremely high radiopurity in (TI)-T-208 and Bi-214 for the SuperNEMO double beta decay source foils. A modular prototype, called BiPo-1, with 0.8 m(2) of sensitive surface area, has been running in the Modane Underground Laboratory since February, 2008. The goal of BiPo-1 is to measure the different components of the background and in particular the surface radiopurity of the plastic scintillators that make up the detector. The first phase of data collection has been dedicated to the measurement of the radiopurity in (TI)-T-208. After more than one year of background measurement, a surface activity of the scintillators of A((TI)-T-208) = 1.5 μBq/m(2) is reported here. Given this level of background, a larger BiPo detector having 12 m(2) of active surface area, is able to qualify the radiopurity of the SuperNEMO selenium double beta decay foils with the required sensitivity of A((TI)-T-208) <2 μBq/kg (90% CL.) with a six month measurement.
Address [Argyriades, J.; Augier, C.; Bongrand, M.; Bourgeois, C.; Breton, D.; Briere, M.; Broudin-Bay, G.; Garrido, X.; Jenzer, S.; Jullian, S.; Sarazin, X.; Simard, L.; Szklarz, G.] Univ Paris 11, LAL, CNRS, IN2P3, F-91405 Orsay, France, Email: sarazin@lal.in2p3.fr
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes (up) ISI:000282530300016 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 364
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Author AGATA Collaboration; Doncel, M.; Recchia, F.; Quintana, B.; Gadea, A.; Farnea, E.
Title Experimental test of the background rejection, through imaging capability, of a highly segmented AGATA germanium detector Type Journal Article
Year 2010 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 622 Issue 3 Pages 614-618
Keywords Gamma spectroscopy; Gamma tracking; Imaging; Position-sensitive germanium detectors
Abstract The development of highly segmented germanium detectors as well as the algorithms to identify the position of the interaction within the crystal opens the possibility to locate the gamma-ray source using Compton imaging algorithms. While the Compton-suppression shield, coupled to the germanium detector in conventional arrays, works also as an active filter against the gamma rays originated outside the target, the new generation of position sensitive gamma-ray detector arrays has to fully rely on tracking capabilities for this purpose. In specific experimental conditions, as the ones foreseen at radioactive beam facilities, the ability to discriminate background radiation improves the sensitivity of the gamma spectrometer. In this work we present the results of a measurement performed at the Laboratori Nazionali di Legnaro (LNL) aiming the evaluation of the AGATA detector capabilities to discriminate the origin of the gamma rays on an event-by-event basis. It will be shown that, exploiting the Compton scattering formula, it is possible to track back gamma rays coming from different positions, assigning them to specific emitting locations. These imaging capabilities are quantified for a single crystal AGATA detector.
Address [Doncel, M.; Quintana, B.] Univ Salamanca, Lab Radiac Ionizantes, E-37008 Salamanca, Spain, Email: doncel@usal.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes (up) ISI:000282562700017 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 257
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Author Carbone, C.; Mena, O.; Verde, L.
Title Cosmological parameters degeneracies and non-Gaussian halo bias Type Journal Article
Year 2010 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 020 - 17pp
Keywords power spectrum; redshift surveys; galaxy clusters; cosmological parameters from LSS
Abstract We study the impact of the cosmological parameters uncertainties on the measurements of primordial non-Gaussianity through the large-scale non-Gaussian halo bias effect. While this is not expected to be an issue for the standard Lambda CDM model, it may not be the case for more general models that modify the large-scale shape of the power spectrum. We consider the so-called local non-Gaussianity model, parametrized by the f(NL) non-Gaussianity parameter which is zero for a Gaussian case, and make forecasts on f(NL) from planned surveys, alone and combined with a Planck CMB prior. In particular, we consider EUCLID- and LSST-like surveys and forecast the correlations among f(NL) and the running of the spectral index alpha(s), the dark energy equation of state w, the effective sound speed of dark energy perturbations c(s)(2), the total mass of massive neutrinos M-nu = Sigma m(nu), and the number of extra relativistic degrees of freedom N-nu(rel). Neglecting CMB information on f(NL) and scales k > 0.03h/Mpc, we find that, if N-nu(rel) is assumed to be known, the uncertainty on cosmological parameters increases the error on f(NL) by 10 to 30% depending on the survey. Thus the f(NL) constraint is remarkable robust to cosmological model uncertainties. On the other hand, if N-nu(rel) is simultaneously constrained from the data, the f(NL) error increases by similar to 80%. Finally, future surveys which provide a large sample of galaxies or galaxy clusters over a volume comparable to the Hubble volume can measure primordial non-Gaussianity of the local form with a marginalized 1-sigma error of the order Delta f(NL) similar to 2 – 5, after combination with CMB priors for the remaining cosmological parameters. These results are competitive with CMB bispectrum constraints achievable with an ideal CMB experiment.
Address [Carbone, Carmelita] Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy, Email: carmelita.carbone@unibo.it
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes (up) ISI:000283573200010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 347
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Author Wagner, C.; Verde, L.; Boubekeur, L.
Title N-body simulations with generic non-Gaussian initial conditions I: power spectrum and halo mass function Type Journal Article
Year 2010 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 10 Issue 10 Pages 022 - 24pp
Keywords power spectrum; cosmological simulations; initial conditions and eternal universe; galaxy clusters
Abstract We address the issue of setting up generic non-Gaussian initial conditions for N-body simulations. We consider inflationary-motivated primordial non-Gaussianity where the perturbations in the Bardeen potential are given by a dominant Gaussian part plus a non-Gaussian part specified by its bispectrum. The approach we explore here is suitable for any bispectrum, i.e. it does not have to be of the so-called separable or factorizable form. The procedure of generating a non-Gaussian field with a given bispectrum (and a given power spectrum for the Gaussian component) is not univocal, and care must be taken so that higher-order corrections do not leave a too large signature on the power spectrum. This is so far a limiting factor of our approach. We then run N-body simulations for the most popular inflationary-motivated non-Gaussian shapes. The halo mass function and the non-linear power spectrum agree with theoretical analytical approximations proposed in the literature, even if they were so far developed and tested only for a particular shape (the local one). We plan to make the simulations outputs available to the community via the non-Gaussian simulations comparison project web site http://icc.ub.edu/similar to liciaverde/NGSCP.html.
Address [Wagner, Christian; Verde, Licia] Univ Barcelona, ICCUB IEEC, E-08028 Barcelona, Spain, Email: cwagner@icc.ub.edu
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes (up) ISI:000283577600013 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 339
Permanent link to this record