|   | 
Details
   web
Records
Author Poley, L. et al; Lacasta, C.
Title Investigations into the impact of locally modified sensor architectures on the detection efficiency of silicon micro-strip sensors Type Journal Article
Year 2017 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 12 Issue Pages P07006 - 17pp
Keywords Si microstrip and pad detectors; Inspection with x-rays; Hybrid detectors; Instrumentation for particle accelerators and storage rings – high energy (linear accelerators, synchrotrons)
Abstract The High Luminosity Upgrade of the LHC will require the replacement of the Inner Detector of ATLAS with the Inner Tracker (ITk) in order to cope with higher radiation levels and higher track densities. Prototype silicon strip detector modules are currently developed and their performance is studied in both particle test beams and X-ray beams. In previous test beam measurements of prototype modules, the response of silicon sensors has been studied in detailed scans across individual sensor strips. These scans found instances of sensor strips collecting charge across areas on the sensor deviating from the geometrical width of a sensor strip. The variations have been linked to local features of the sensor architecture. This paper presents results of detailed sensor measurements in both X-ray and particle beams investigating the impact of sensor features (metal pads and p-stops) on the sensor strip response.
Address [Poley, L.] DESY, Notkestr, Hamburg, Germany, Email: Anne-Luise.Poley@desy.de
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title (up)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000406392600006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3234
Permanent link to this record
 

 
Author Albiol, F.; Corbi, A.; Albiol, A.
Title Evaluation of modern camera calibration techniques for conventional diagnostic X-ray imaging settings Type Journal Article
Year 2017 Publication Radiological Physics and Technology Abbreviated Journal Radiol. Phys. Technol.
Volume 10 Issue 1 Pages 68-81
Keywords Conventional X-ray camera calibration; Detector resolution; Intrinsic and extrinsic parameters; Zhang's method; Direct linear transform; Tsai's approach
Abstract We explore three different alternatives for obtaining intrinsic and extrinsic parameters in conventional diagnostic X-ray frameworks: the direct linear transform (DLT), the Zhang method, and the Tsai approach. We analyze and describe the computational, operational, and mathematical background differences for these algorithms when they are applied to ordinary radiograph acquisition. For our study, we developed an initial 3D calibration frame with tin cross-shaped fiducials at specific locations. The three studied methods enable the derivation of projection matrices from 3D to 2D point correlations. We propose a set of metrics to compare the efficiency of each technique. One of these metrics consists of the calculation of the detector pixel density, which can be also included as part of the quality control sequence in general X-ray settings. The results show a clear superiority of the DLT approach, both in accuracy and operational suitability. We paid special attention to the Zhang calibration method. Although this technique has been extensively implemented in the field of computer vision, it has rarely been tested in depth in common radiograph production scenarios. Zhang's approach can operate on much simpler and more affordable 2D calibration frames, which were also tested in our research. We experimentally confirm that even three or four plane-image correspondences achieve accurate focal lengths.
Address [Albiol, Francisco; Corbi, Alberto] Univ Valencia, CSIC, Inst Fis Corpuscular, Valencia, Spain, Email: alberto.corbi@ific.uv.es
Corporate Author Thesis
Publisher Springer Japan Kk Place of Publication Editor
Language English Summary Language Original Title (up)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1865-0333 ISBN Medium
Area Expedition Conference
Notes WOS:000405867100009 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 3238
Permanent link to this record
 

 
Author Bhattacharya, A.; Esmaili, A.; Palomares-Ruiz, S.; Sarcevic, I.
Title Probing decaying heavy dark matter with the 4-year IceCube HESE data Type Journal Article
Year 2017 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 027 - 36pp
Keywords dark matter theory; neutrino astronomy; neutrino detectors; ultra high energy photons and neutrinos
Abstract After the first four years of data taking, the IceCube neutrino telescope has observed 54 high-energy starting events (HESE) with deposited energies between 20TeV and 2PeV. The background from atmospheric muons and neutrinos is expected to be of about 20 events, all below 100TeV, thus pointing towards the astrophysical origin of about 8 events per year in that data set. However, their precise origin remains unknown. Here, we perform a detailed analysis of this event sample (considering simultaneously the energy, hemisphere and topology of the events) by assuming two contributions for the signal events: an isotropic power-law flux and a flux from decaying heavy dark matter. We fit the mass and lifetime of the dark matter and the normalization and spectral index of an isotropic power-law flux, for various decay channels of dark matter. We find that a significant contribution from dark matter decay is always slightly favored, either to explain the excess below 100TeV, as in the case of decays to quarks or, as in the case of neutrino channels, to explain the three multi-PeV events. Also, we consider the possibility to interpret all the data by dark matter decays only, considering various combinations of two decay channels. We show that the decaying dark matter scenario provides a better fit to HESE data than the isotropic power-law flux.
Address [Bhattacharya, Atri] Univ Liege, Space Sci Technol & Astrophys Res STAR Inst, Bat B5a, B-4000 Liege, Belgium, Email: a.bhattacharya@ulg.ac.be;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title (up)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000406420500009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3243
Permanent link to this record
 

 
Author Garcia, A.R.; Mendoza, E.; Cano-Ott, D.; Nolte, R.; Martinez, T.; Algora, A.; Tain, J.L.; Banerjee, K.; Bhattacharya, C.
Title New physics model in GEANT4 for the simulation of neutron interactions with organic scintillation detectors Type Journal Article
Year 2017 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 868 Issue Pages 73-81
Keywords Organic scintillator; Neutron detectors; GEANT4; BC501A; NE213; EJ301
Abstract The accurate determination of the response function of organic scintillation neutron detectors complements their experimental characterization. Monte Carlo simulations with GEANT4 can reduce the effort and cost implied, especially for complex detection systems for which the characterization is more challenging. Previous studies have reported on the inaccuracy of GEANT4 in the calculation of the neutron response of organic scintillation detectors above 6 MeV, due to an incomplete description of the neutron-induced alpha production reactions on carbon. We have improved GEANT4 in this direction by incorporating models and data from NRESP, an excellent Monte Carlo simulation tool developed at the Physikalisch-Technische Bundesanstalt (PTB), Germany, for the specific purpose of calculating the neutron response function of organic scintillation detectors. The results have been verified against simulations with NRESP and validated against Time-Of-Flight measurements with an NE213 detector at PTB. This work has potential applications beyond organic scintillation detectors, to other types of detectors where reactions induced by fast neutrons on carbon require an accurate description.
Address [Garcia, A. R.; Mendoza, E.; Cano-Ott, D.; Martinez, T.] Ctr Invest Energet Medioambientales & Tecnol CIEM, Ave Complutense 40, Madrid 28040, Spain, Email: daniel.cano@ciemat.es
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title (up)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000408406700012 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3250
Permanent link to this record
 

 
Author Korichi, A.; Lauritsen, T.; Wilson, A.N.; Dudouet, J.; Clement, E.; Lalovic, N.; Perez-Vidal, R.M.; Pietri, S.; Ralet, D.; Stezowski, O.
Title Performance of a gamma-ray tracking array: Characterizing the AGATA array using a Co-60 source Type Journal Article
Year 2017 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 872 Issue Pages 80-86
Keywords Segmented germanium detectors; Efficiency measurements; gamma-ray tracking; AGATA; gamma-ray spectroscopy; Nuclear structure
Abstract The AGATA (Advanced GAmma Tracking Array) tracking detector is being designed to far surpass the performance of the previous generation, Compton-suppressed arrays. In this paper, a characterization of AGATA is provided based on data from the second GSI campaign. Emphasis is placed on the proper corrections required to extract the absolute photopeak efficiency and peak-to-total ratio. The performance after tracking is extracted and GEANT4 simulations are used both to understand the results and to scale the measurements up to predicted values for the full 4 pi implementation of the device.
Address [Korichi, A.] CNRS, IN2P3, CSNSM, Bat 104-108,Orsay Campus, F-91405 Orsay, France, Email: Amel.Korichi@csnsm.in2p3.fr
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title (up)
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000411755300009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3311
Permanent link to this record