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Author (down) n_TOF Collaboration (Alcayne, V. et al); Balibrea-Correa, J.; Domingo-Pardo, C.; Lerendegui-Marco, J.; Babiano-Suarez, V.; Ladarescu, I. url  doi
openurl 
  Title A Segmented Total Energy Detector (sTED) optimized for (n,γ) cross-section measurements at n_TOF EAR2 Type Journal Article
  Year 2024 Publication Radiation Physics and Chemistry Abbreviated Journal Radiat. Phys. Chem.  
  Volume 217 Issue Pages 11pp  
  Keywords Neutron capture; PHWT; Scintillation detectors; Monte Carlo simulation  
  Abstract The neutron time-of-flight facility nTOF at CERN is a spallation source dedicated to measurements of neutroninduced reaction cross-sections of interest in nuclear technologies, astrophysics, and other applications. Since 2014, Experimental ARea 2 (EAR2) is operational and delivers a neutron fluence of similar to 4 center dot 10(7) neutrons per nominal proton pulse, which is similar to 50 times higher than the one of Experimental ARea 1 (EAR1) of similar to 8 center dot 10(5) neutrons per pulse. The high neutron flux at EAR2 results in high counting rates in the detectors that challenged the previously existing capture detection systems. For this reason, a Segmented Total Energy Detector (sTED) has been developed to overcome the limitations in the detector's response, by reducing the active volume per module and by using a photo-multiplier (PMT) optimized for high counting rates. This paper presents the main characteristics of the sTED, including energy and time resolution, response to gamma-rays, and provides as well details of the use of the Pulse Height Weighting Technique (PHWT) with this detector. The sTED has been validated to perform neutron-capture cross-section measurements in EAR2 in the neutron energy range from thermal up to at least 400 keV. The detector has already been successfully used in several measurements at nTOF EAR2.  
  Address [Alcayne, V.; Cano-Ott, D.; Garcia, J.; Gonzalez-Romero, E.; Martinez, T.; de Rada, A. Perez; Plaza, J.; Sanchez-Caballero, A.; Mendoza, E.] Ctr Invest Energet Medioambient & Tecnol CIEMAT, Madrid, Spain, Email: victor.alcayne@ciemat.es  
  Corporate Author Thesis  
  Publisher Pergamon-Elsevier Science Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0969-806x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001185584800001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5999  
Permanent link to this record
 

 
Author (down) Nzongani, U.; Zylberman, J.; Doncecchi, C.E.; Perez, A.; Debbasch, F.; Arnault, P. url  doi
openurl 
  Title Quantum circuits for discrete-time quantum walks with position-dependent coin operator Type Journal Article
  Year 2023 Publication Quantum Information Processing Abbreviated Journal Quantum Inf. Process.  
  Volume 22 Issue 7 Pages 270 - 46pp  
  Keywords Quantum walks; Quantum circuits; Quantum simulation  
  Abstract The aim of this paper is to build quantum circuits that implement discrete-time quantum walks having an arbitrary position-dependent coin operator. The position of the walker is encoded in base 2: with n wires, each corresponding to one qubit, we encode 2(n) position states. The data necessary to define an arbitrary position-dependent coin operator is therefore exponential in n. Hence, the exponentiality will necessarily appear somewhere in our circuits. We first propose a circuit implementing the position-dependent coin operator, that is naive, in the sense that it has exponential depth and implements sequentially all appropriate position-dependent coin operators. We then propose a circuit that “transfers” all the depth into ancillae, yielding a final depth that is linear in n at the cost of an exponential number of ancillae. Themain idea of this linear-depth circuit is to implement in parallel all coin operators at the different positions. Reducing the depth exponentially at the cost of having an exponential number of ancillae is a goal which has already been achieved for the problem of loading classical data on a quantum circuit (Araujo in Sci Rep 11:6329, 2021) (notice that such a circuit can be used to load the initial state of the walker). Here, we achieve this goal for the problem of applying a position-dependent coin operator in a discrete-time quantum walk. Finally, we extend the result of Welch (New J Phys 16:033040, 2014) from position-dependent unitaries which are diagonal in the position basis to position-dependent 2 x 2-block-diagonal unitaries: indeed, we show that for a position dependence of the coin operator (the block-diagonal unitary) which is smooth enough, one can find an efficient quantum-circuit implementation approximating the coin operator up to an error epsilon (in terms of the spectral norm), the depth and size of which scale as O(1/epsilon). A typical application of the efficient implementation would be the quantum simulation of a relativistic spin-1/2 particle on a lattice, coupled to a smooth external gauge field; notice that recently, quantum spatial-search schemes have been developed which use gauge fields as the oracle, to mark the vertex to be found (Zylberman in Entropy 23:1441, 2021), (Fredon arXiv:2210.13920). A typical application of the linear-depth circuit would be when there is spatial noise on the coin operator (and hence a non-smooth dependence in the position).  
  Address [Nzongani, Ugo; Doncecchi, Carlo-Elia; Arnault, Pablo] Univ Paris Saclay, CNRS, INRIA, Lab Methodes Formelles,ENS Paris Saclay, F-91190 Gif Sur Yvette, France, Email: ugo.nzongani@universite-paris-saclay.fr;  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1570-0755 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:001022408900002 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5587  
Permanent link to this record
 

 
Author (down) Nunes, R.C.; Vagnozzi, S.; Kumar, S.; Di Valentino, E.; Mena, O. url  doi
openurl 
  Title New tests of dark sector interactions from the full-shape galaxy power spectrum Type Journal Article
  Year 2022 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 105 Issue 12 Pages 123506 - 18pp  
  Keywords  
  Abstract We explore the role of redshift-space galaxy clustering data in constraining nongravitational interactions between dark energy (DE) and dark matter (DM), for which state-of-the-art limits have so far been obtained from late-time background measurements. We use the joint likelihood for prereconstruction full-shape (FS) galaxy power spectrum and postreconstruction Baryon Acoustic Oscillation (BAO) measurements from the BOSS DR12 sample, alongside Cosmic Microwave Background (CMB) data from Planck: from this dataset combination we infer H0 1/4 68.02+0.49 and the 2?? lower limit ?? > ???0.12, among the strongest limits ever reported on the DM-DE coupling strength ?? for the particular model considered. Contrary to what has been observed for the ??CDM model and simple extensions thereof, we find that the CMB + FS combination returns tighter constraints compared to the CMB + BAO one, suggesting that there is valuable additional information contained in the broadband of the power spectrum. We test this finding by running additional CMB-free analyses and removing sound horizon information, and discuss the important role of the equality scale in setting constraints on DM-DE interactions. Our results reinforce the critical role played by redshift-space galaxy clustering measurements in the epoch of precision cosmology, particularly in relation to tests of nonminimal dark sector extensions of the ??CDM model.  
  Address [Nunes, Rafael C.] Univ Fed Rio Grande Do Sul, Inst Fis, BR-91501970 Porto Alegre, RS, Brazil, Email: rafadcnunes@gmail.com;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000813312800005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5269  
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Author (down) Nunes da Silva, T.; Chinellato, D.D.; Giannini, A.V.; Takahashi, J.; Ferreira, M.N.; Denicol, G.S.; Hippert, M.; Noronha, J.; Luzum, M. url  doi
openurl 
  Title Prehydrodynamic evolution in large and small systems Type Journal Article
  Year 2023 Publication Physical Review C Abbreviated Journal Phys. Rev. C  
  Volume 107 Issue 4 Pages 044901 - 12pp  
  Keywords  
  Abstract We extend our previous investigation of the effects of prehydrodynamic evolution on final-state observables in heavy-ion collisions [38] to smaller systems. We use a state-of-the-art hybrid model for the numerical simulations with optimal parameters obtained from a previous Bayesian study. By studying p-Pb collisions, we find that the effects due to the assumption of a conformal evolution in the prehydrodynamical stage are even more important in small systems. We also show that this effect depends on the time duration of the pre-equilibrium stage, which is further enhanced in small systems. Finally, we show that the recent proposal of a free-streaming with subluminal velocity for the pre-equilibrium stage, thus effectively breaking conformal invariance, can alleviate the contamination of final-state observables. Our study further reinforces the need for moving beyond conformal approaches in pre-equilibrium dynamics modeling, especially when extracting transport coefficients from hybrid models in the high-precision era of heavy-ion collisions.  
  Address [da Silva, T. Nunes] Univ Fed Santa Catarina, Ctr Ciencias Fis & Matemat, Dept Fis, Campus Univ Reitor Joao David Ferreira Lima, BR-88040900 Florianopolis, Brazil, Email: t.j.nunes@ufsc.br;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2469-9985 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000974911400001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5524  
Permanent link to this record
 

 
Author (down) Nieves, J.; Pavao, R.; Tolos, L. url  doi
openurl 
  Title Xi(c) and Xi(b) excited states within a SU(6)(lsf) x HQSS model Type Journal Article
  Year 2020 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C  
  Volume 80 Issue 1 Pages 22 - 12pp  
  Keywords  
  Abstract We study odd parity J = 1/2 and J = 3/2 Xi(c) resonances using a unitarized coupled-channel framework based on a SU(6)(lsf) xHQSS-extended Weinberg-Tomozawa baryon-meson interaction, while paying a special attention to the renormalization procedure. We predict a large molecular Lambda(c)(K) over bar component for the Xi(c) (2790) with a dominant 0(-) light-degree-of-freedom spin configuration. We discuss the differences between the 3/2(-) Lambda(c)(2625) and Xi(c)(2815) states, and conclude that they cannot be SU(3) siblings, whereas we predict the existence of other Xi(c)-states, one of them related to the two-pole structure of the Lambda(c)(2595). It is of particular interest a pair of J = 1/2 and J = 3/2 poles, which form a HQSS doublet and that we tentatively assign to the Xi(c)(2930) and Xi(c)(2970), respectively. Within this picture, the Xi(c)(2930) would be part of a SU(3) sextet, containing either the Omega(c)(3090) or the Omega(c)(3119), and that would be completed by the Sigma(c)(2800). Moreover, we identify a J = 1/2 sextet with the Xi(b)(6227) state and the recently discovered Sigma(b)(6097). Assuming the equal spacing rule and to complete this multiplet, we predict the existence of a J = 1/2 Omega(b) odd parity state, with a mass of 6360 MeV and that should be seen in the Xi(b) (K) over bar channel.  
  Address [Nieves, J.; Pavao, R.] UV, CSIC, Inst Invest Paterna, Inst Fis Corpuscular,Ctr Mixto, Aptdo 22085, Valencia 46071, Spain, Email: tolos@ice.csic.es  
  Corporate Author Thesis  
  Publisher Springer Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1434-6044 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000514590400004 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4295  
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