International Federation of Gynecology and Obstetrics

Publication year: 2012
Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Available online 2 February 2012

Reiner Zorn

For high resolution time-of-flight neutron scattering spectrometers, a significant contribution to the instrumental resolution broadening will be due to the flight path uncertainty induced by the sample size. In linear approximation, this contribution is an additional convolution of the resolution function with the scaled distribution of flight path lengths. This distribution, its moments, and its Fourier transform will be calculated for flat film and hollow-cylindrical sample geometry. The minima in the Fourier transform are shown to correspond to experimentally inaccessible ranges of the intermediate scattering function.

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Publication year: 2012
Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Available online 2 February 2012

J.A. Aguilar, I. Al Samarai, A. Albert, M. André, M. Anghinolfi, ...

The primary aim of ANTARES is neutrino astronomy with upward going muons created in charged current muon neutrino interactions in the detector and its surroundings. Downward going muons are background for neutrino searches. These muons are the decay products of cosmic-ray collisions in the Earth's atmosphere far above the detector. This paper presents a method to identify and count electromagnetic showers induced along atmospheric muon tracks with the ANTARES detector. The method is applied to both cosmic muon data and simulations and its applicability to the reconstruction of muon event energies is demonstrated.

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Publication year: 2012
Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Available online 2 February 2012

Sezen Sekmenon behalf of the CMS Collaboration

We report on the dark matter searches performed by the Compact Muon Solenoid Experiment using the 35 pbof 7 TeVppdata collected by the CERN Large Hadron Collider in 2010. All observations so far were found to be consistent with the Standard Model predictions. The search results were used for setting exclusion limits on various new physics scenarios.

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Publication year: 2012
Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Available online 2 February 2012

Andrea Mammarella

We have studied the lightest masses in the fermionic sector of an anomalousextension of the Minimal Supersymmetric Standard Model (MSSM) inspired by brane constructions. The LSP of this model is an XWIMP (extremely weak interaction particle). We have studied its relic density in the cases in which there is mixing with the neutralinos of the MSSM and in the case in which there is not such mixing. We have showed that this extended model can satisfy the WMAP data. To perform this calculation we have modified the DarkSUSY package.

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Publication year: 2012
Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Available online 3 February 2012

A.K. Çiftçi, R. Çiftçi, H. Yıldız, K. Zengin

The Turkish Accelerator Center Synchrotron Radiation, TAC-SR, is the first project for accelerator based synchrotron and applied researches supported by Turkish Republic Ministry of Development(TRMOD). This initiative taken by the Turkish Government aims at the construction of advanced research infrastructures based on particle accelerators, considered an important asset to support and foster the national research in science and technology. In this framework, the primary objective of the TAC-SR working group is to produce the preliminary design of the Synchrotron Radiation Source. Achieved beam emittance of the studied design is nominally 1.18 nm. Also, the frequency map analysis and the dynamic aperture calculations for the TAC Synchrotron Storage Ring are optimised. For demonstration, parameter sets and performance of some undulators are presented. It is seen that the insertion devices with the proposed parameter sets acquire competitive brilliance values to cover 10 eV–50 keV photon energy range.

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Publication year: 2012
Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Available online 31 January 2012

A.M. Ivanov, N.B. Strokan, A.A. Lebedev

A polarization effect characteristically occurs in detectors based on wide-bandgap materials at considerable concentrations of radiation defects. The appearance of an electromotive force in the bulk of a detector is due to the long-term capture of carriers at deep levels related to radiation centers. The kinetics and strength of the polarization field have been determined. The carrier capture by the radiation centers can be controlled by varying the detector temperature, with a compromise reached at the “optimal” temperature between the generation current and the position of the deepest of the levels whose contribution to the loss of charge via capture is negligible. It has been found that the depth of a level of this kind (related to the energy gap width) is close to 1/3, irrespective of a material. The optimal temperatures are strictly individual for materials.

Highlights

► We analyze the strength of the polarization field and his kinetics. ► We find the optimal operating temperature at which carrier capture can be precluded. ► Simultaneously the generation current does not exceed a prescribed value. ► A comparison of the materials radiation hardnesses is correct at optimal temperature.

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Publication year: 2012
Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Available online 31 January 2012

Marco Battaglia, Dario Bisello, Richard Celestre, Devis Contarato, Peter Denes, ...

This paper presents the results of the characterisation of a back-illuminated pixel sensor manufactured in Silicon-on-Insulator technology on a high-resistivity substrate with soft X-rays. The sensor is thinned and a low energy phosphorus implantation is performed on the back-plane. The response to X-rays from 2.12 to 8.6 keV is evaluated with fluorescence radiation at the LBNL Advanced Light Source.

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Publication year: 2012
Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Available online 31 January 2012

G.A. Gómez-Vargas

Theis a supersymmetric model that has been proposed to solve the problems generated by other supersymmetric extensions of the standard model of particle physics. Given thatR-parity is broken in the, the gravitino is a natural candidate for decaying dark matter since its lifetime becomes much longer than the age of the Universe. In this model, gravitino dark matter could be detectable through the emission of a monochromatic gamma ray in a two-body decay. We study the prospects of the Fermi-LAT telescope to detect such monochromatic lines in 5 years of observations of the most massive nearby extragalactic objects. We focus on the Virgo galaxy cluster, since it is associated to a particularly high signal-to-noise ratio and is located at high Galactic latitude. The simulation of both signal and background gamma-ray events is carried out with the Fermi Science Tools, and the dark matter distribution around Virgo is taken from anN-body simulation, with constrained initial conditions provided by the CLUES project. We find that a gravitino with a mass range of 0.6–2 GeV, and with a lifetime range of aboutwould be detectable by the Fermi-LAT with a signal-to-noise ratio larger than 3. We also obtain that gravitino masses larger than about 4 GeV are already excluded in theby Fermi-LAT data of the galactic halo. These proceedings are based on Ref.

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Publication year: 2012
Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Available online 1 February 2012

K. LaihemFor the IceCube Collaboration

New detection techniques for (GZK) neutrinos are required for instrumenting a large detector volume needed to observe the low neutrino fluxes at the EeV energy range. Studies on a larger IceCube Neutrino Observatory at the South Pole have been intensively investigated in the last decade. A larger effective volume at a reasonable cost is possible if an acoustic array is a part of a large hybrid detector which includes radio and the existing optical array. The feasibility and the physics capabilities of an acoustic array at the South Pole depend on the knowledge of the acoustic properties of the ice such as the sound speed, the attenuation length, the background noise level and the transient rate. To investigate the ice properties, the first three acoustic strings of the South Pole Acoustic Test Setup (SPATS) have been deployed in the austral summer 2006/2007, then completed with an additional string in 2007/2008. With its four strings SPATS was able to evaluate in situ the acoustic properties of the South Pole ice in the 10–100 kHz frequency range. In this paper the performance of SPATS is described, results on the acoustic ice properties are presented and a new drilling method to deploy acoustic strings in ice is introduced.

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Publication year: 2012
Source: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Available online 2 February 2012

Carlos Muñoz

Indirect dark matter searchers are briefly reviewed. Current experimental data from satellites and Cherenkov telescopes searching for antimatter and gamma rays in galactic and extragalactic regions, are compared with predictions from theoretical models of dark matter. The analysis is focused on WIMPs such as the neutralino and the sneutrino, and superWIMPs such as the gravitino, in several interesting supersymmetric models. In particular, the discussion is carried out in the context ofR-parity conserving models such as the MSSM, NMSSM, and NMSSM with dynamical neutrino masses, and theR-parity violating model.

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