Records |
Author |
Araujo Filho, A.A. |
Title |
Thermodynamics of massless particles in curved spacetime |
Type |
Journal Article |
Year |
2023 |
Publication |
International Journal of Geometric Methods in Modern Physics |
Abbreviated Journal |
Int. J. Geom. Methods Mod. Phys. |
Volume |
12 |
Issue |
13 |
Pages |
2350226 - 40pp |
Keywords |
Einstein-aether; thermodynamic properties; curved spacetime |
Abstract |
This work is devoted to study the behavior of massless particles within the context of curved spacetime. In essence, we investigate the consequences of the scale factor C(?) of the Friedmann-Robertson-Walker metric in the Einstein-aether formalism to study photon-like particles. To do so, we consider the system within the canonical ensemble formalism in order to derive the following thermodynamic state quantities: spectral radiance, Helmholtz free energy, pressure, entropy, mean energy and the heat capacity. Moreover, the correction to the Stefan-Boltzmann law and the equation of states are also provided. Particularly, we separate our study within three distinct cases, i.e. s = 0, p = 0; s = 1, p = 1; s = 2, p = 1. In the first one, the results are derived numerically. Nevertheless, for the rest of the cases, all the calculations are accomplished analytically showing explicitly the dependence of the scale factor C(?) and the Riemann zeta function ?(s). Furthermore, our analyses are accomplished in general taking into account three different regimes of temperature of the universe, i.e. the inflationary era (T = 10(13)GeV), the electroweak epoch (T = 10(3)GeV) and the cosmic microwave background (T = 10(-13)GeV). |
Address |
[Araujo Filho, A. A.] Univ Fed Cearra UFC, Dept Fis, Campus Pici,CP 6030, BR-60455760 Fortaleza, CE, Brazil, Email: dilto@fisica.ufc.br |
Corporate Author |
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Thesis |
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Publisher |
World Scientific Publ Co Pte Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0219-8878 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001048378900001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5613 |
Permanent link to this record |
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Author |
Oliveira, C.A.B.; Sorel, M.; Martin-Albo, J.; Gomez-Cadenas, J.J.; Ferreira, A.L.; Veloso, J.F.C.A. |
Title |
Energy resolution studies for NEXT |
Type |
Journal Article |
Year |
2011 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
Volume |
6 |
Issue |
|
Pages |
P05007 - 13pp |
Keywords |
Scintillators, scintillation and light emission processes (solid, gas and liquid scintillators); Detector modelling and simulations II (electric fields, charge transport, multiplication and induction, pulse formation, electron emission etc); Large detector systems for particle and astroparticle physics; Time projection chambers |
Abstract |
This work aims to present the current state of simulations of electroluminescence (EL) produced in gas-based detectors with special interest for NEXT – Neutrino Experiment with a Xenon TPC. NEXT is a neutrinoless double beta decay experiment, thus needs outstanding energy resolution which can be achieved by using electroluminescence. The process of light production is reviewed and properties such as EL yield and associated fluctuations, excitation and electroluminescence efficiencies, and energy resolution, are calculated. An EL production region with a 5 mm width gap between two infinite parallel planes is considered, where a uniform electric field is produced. The pressure and temperature considered are 10 bar and 293 K, respectively. The results show that, even for low values of VUV photon detection efficiency, good energy resolution can be achieved: below 0.4% (FWHM) at Q(beta beta) = 2.458 MeV. |
Address |
[Oliveira, CAB; Ferreira, AL; Veloso, JFCA] Univ Aveiro, Dept Phys, i3N, P-3810193 Aveiro, Portugal, Email: carlos.oliveira@ua.pt |
Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1748-0221 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000294491900008 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ elepoucu @ |
Serial |
747 |
Permanent link to this record |
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Author |
Pasqualato, G. et al; Gadea, A.; Jurado, M. |
Title |
An alternative viewpoint on the nuclear structure towards 100Sn: Lifetime measurements in 105Sn |
Type |
Journal Article |
Year |
2023 |
Publication |
Physics Letters B |
Abbreviated Journal |
Phys. Lett. B |
Volume |
845 |
Issue |
|
Pages |
138148 - 7pp |
Keywords |
Nuclear structure; gamma-ray spectroscopy; Transition probabilities; Neutron-deficient isotopes; Odd-mass nuclei; Lifetime measurements |
Abstract |
This work aims at presenting an alternative approach to the long standing problem of the B(E2) values in Sn isotopes in the vicinity of the N=Z double-magic nucleus Sn-100, until now predominantly measured with relativistic and intermediate-energy Coulomb excitation reactions. The direct measurement of the lifetime of low-lying excited states in odd-even Sn isotopes provides a new and precise guidance for the theoretical description of the nuclear structure in this region. Lifetime measurements have been performed in Sn-105 for the first time with the coincidence Recoil Distance Doppler Shift technique. The lifetime results for the 7/2(1)(+) first excited state and the 11/2(1)(+) state, 2(+)(Sn-104) circle times nu 1g(7/2) multiplet member, are discussed in comparison with state-of-the-art shell model and mean field calculations, highlighting the crucial contribution of proton excitation across the core of Sn-100. The reduced transition probability B(E2) of the 11/2(1)(+) core-coupled state points out an enhanced staggering with respect to the B(E2; 2(1)(+) -> 0(1)(+)) in the even-mass Sn-104 and Sn-106 isotopes. |
Address |
[Pasqualato, G.; Mengonia, D.; Goasduff, A.; Lenzi, S. M.; Menegazzo, R.; Montaner-Piza, A.; Recchia, F.; Testov, D.] INFN, Sez Padova, Padua, Italy, Email: giorgia.pasqualato@IJCLAB.IN2P3.FR |
Corporate Author |
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Thesis |
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Publisher |
Elsevier |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0370-2693 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:001084426400001 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
5725 |
Permanent link to this record |
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Author |
Egea Canet, F.J. et al; Gadea, A.; Huyuk, T. |
Title |
Digital Front-End Electronics for the Neutron Detector NEDA |
Type |
Journal Article |
Year |
2015 |
Publication |
IEEE Transactions on Nuclear Science |
Abbreviated Journal |
IEEE Trans. Nucl. Sci. |
Volume |
62 |
Issue |
3 |
Pages |
1063-1069 |
Keywords |
Digital systems; front-end electronics; neutron detectors; neutron-gamma discrimination |
Abstract |
This paper presents the design of the NEDA (Neutron Detector Array) electronics, a first attempt to involve the use of digital electronics in large neutron detector arrays. Starting from the front-end modules attached to the PMTs (PhotoMultiplier Tubes) and ending up with the data processing workstations, a comprehensive electronic system capable of dealing with the acquisition and pre-processing of the neutron array is detailed. Among the electronic modules required, we emphasize the front-end analog processing, the digitalization, digital pre-processing and communications firmware, as well as the integration of the GTS (Global Trigger and Synchronization) system, already used successfully in AGATA (Advanced Gamma Tracking Array). The NEDA array will be available for measurements in 2016. |
Address |
[Egea Canet, F. J.; Gonzalez, V.; Sanchis, E.] Univ Valencia, Dept Elect Engn, Escola Tecn Super Engn, Valencia, Spain, Email: jaegea@ific.uv.es |
Corporate Author |
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Thesis |
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Publisher |
Ieee-Inst Electrical Electronics Engineers Inc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0018-9499 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000356458000029 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
yes |
Call Number |
IFIC @ pastor @ |
Serial |
2279 |
Permanent link to this record |
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Author |
Carrio, F.; Castillo Gimenez, V.; Ferrer, A.; Gonzalez, V.; Higon-Rodriguez, E.; Marin, C.; Moreno, P.; Sanchis, E.; Solans, C.; Valero, A.; Valls Ferrer, J.A. |
Title |
Optical Link Card Design for the Phase II Upgrade of TileCal Experiment |
Type |
Journal Article |
Year |
2011 |
Publication |
IEEE Transactions on Nuclear Science |
Abbreviated Journal |
IEEE Trans. Nucl. Sci. |
Volume |
58 |
Issue |
4 |
Pages |
1657-1663 |
Keywords |
High energy physics instrumentation computing; optical-fiber communication high-speed electronics; programmable logic devices |
Abstract |
This paper presents the design of an optical link card developed in the frame of the R&D activities for the phase 2 upgrade of the TileCal experiment. This board, that is part of the evaluation of different technologies for the final choice in the next years, is designed as a mezzanine that can work independently or be plugged in the optical multiplexer board of the TileCal backend electronics. It includes two SNAP 12 optical connectors able to transmit and receive up to 75 Gb/s and one SFP optical connector for lower speeds and compatibility with existing hardware as the read out driver. All processing is done in a Stratix II GX field-programmable gate array (FPGA). Details are given on the hardware design, including signal and power integrity analysis, needed when working with these high data rates and on firmware development to obtain the best performance of the FPGA signal transceivers and for the use of the GBT protocol. |
Address |
[Carrio, F; Gonzalez, V; Marin, C; Sanchis, E] Univ Valencia, Dept Elect Engn, E-46100 Valencia, Spain, Email: vicente.gonzalez@uv.es |
Corporate Author |
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Thesis |
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Publisher |
Ieee-Inst Electrical Electronics Engineers Inc |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0018-9499 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000293975700037 |
Approved |
no |
Is ISI |
yes |
International Collaboration |
no |
Call Number |
IFIC @ elepoucu @ |
Serial |
722 |
Permanent link to this record |