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Author Angles-Castillo, A.; Bañuls, M.C.; Perez, A.; De Vega, I.
Title Prethermalization of quantum systems interacting with non-equilibrium environments Type Journal Article
Year 2020 Publication New Journal of Physics Abbreviated Journal New J. Phys.
Volume 22 Issue 8 Pages 083067 - 17pp
Keywords open quantum systems; prethermalization; master equations
Abstract The usual paradigm of open quantum systems falls short when the environment is actually coupled to additional fields or components that drive it out of equilibrium. Here we explore the simplest such scenario, by considering a two level system coupled to a first thermal reservoir that in turn couples to a second thermal bath at a different temperature. We derive a master equation description for the system and show that, in this situation, the dynamics can be especially rich. In particular, we observe prethermalization, a transitory phenomenon in which the system initially approaches thermal equilibrium with respect to the first reservoir, but after a longer time converges to the thermal state dictated by the temperature of the second environment. Using analytical arguments and numerical simulations, we analyze the occurrence of this phenomenon, and how it depends on temperatures and coupling strengths. The phenomenology gets even richer if the system is placed between two such non-equilibrium environments. In this case, the energy current through the system may exhibit transient features and even switch direction, before the system eventually reaches a non-equilibrium steady state.
Address [Angles-Castillo, Andreu; Perez, Armando] Univ Valencia, CSIC, Dept Fis Teor, Burjassot 46100, Valencia, Spain, Email: banulsm@mpq.mpg.de
Corporate Author Thesis
Publisher (up) 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 1367-2630 ISBN Medium
Area Expedition Conference
Notes WOS:000565705900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4525
Permanent link to this record
 
 
Author Alimena, J. et al; Hirsch, M.; Mamuzic, J.; Mitsou, V.A.; Santra, A.
Title Searching for long-lived particles beyond the Standard Model at the Large Hadron Collider Type Journal Article
Year 2020 Publication Journal of Physics G Abbreviated Journal J. Phys. G
Volume 47 Issue 9 Pages 090501 - 226pp
Keywords beyond the Standard Model; long-lived particles; Large Hadron Collider; high-luminosity LHC; collider phenomenology; high-energy collider experiments
Abstract Particles beyond the Standard Model (SM) can generically have lifetimes that are long compared to SM particles at the weak scale. When produced at experiments such as the Large Hadron Collider (LHC) at CERN, these long-lived particles (LLPs) can decay far from the interaction vertex of the primary proton-proton collision. Such LLP signatures are distinct from those of promptly decaying particles that are targeted by the majority of searches for new physics at the LHC, often requiring customized techniques to identify, for example, significantly displaced decay vertices, tracks with atypical properties, and short track segments. Given their non-standard nature, a comprehensive overview of LLP signatures at the LHC is beneficial to ensure that possible avenues of the discovery of new physics are not overlooked. Here we report on the joint work of a community of theorists and experimentalists with the ATLAS, CMS, and LHCb experiments-as well as those working on dedicated experiments such as MoEDAL, milliQan, MATHUSLA, CODEX-b, and FASER-to survey the current state of LLP searches at the LHC, and to chart a path for the development of LLP searches into the future, both in the upcoming Run 3 and at the high-luminosity LHC. The work is organized around the current and future potential capabilities of LHC experiments to generally discover new LLPs, and takes a signature-based approach to surveying classes of models that give rise to LLPs rather than emphasizing any particular theory motivation. We develop a set of simplified models; assess the coverage of current searches; document known, often unexpected backgrounds; explore the capabilities of proposed detector upgrades; provide recommendations for the presentation of search results; and look towards the newest frontiers, namely high-multiplicity 'dark showers', highlighting opportunities for expanding the LHC reach for these signals.
Address [Alimena, Juliette; Hill, Christopher S.] Ohio State Univ, Dept Phys, 191 W Woodruff Ave, Columbus, OH 43210 USA, Email: juliette.alimena@cern.ch;
Corporate Author Thesis
Publisher (up) 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 0954-3899 ISBN Medium
Area Expedition Conference
Notes WOS:000570614200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4535
Permanent link to this record
 
 
Author ATLAS Collaboration (Aad, G. et al); Aparisi Pozo, J.A.; Bailey, A.J.; Cabrera Urban, S.; Castillo, F.L.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Higon-Rodriguez, E.; Lacasta, C.; Lozano Bahilo, J.J.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Martinez Agullo, P.; Miñano, M.; Mitsou, V.A.; Moreno Llacer, M.; Poveda, J.; Rodriguez Bosca, S.; Rodriguez Rodriguez, D.; Ruiz-Martinez, A.; Salt, J.; Santra, A.; Sayago Galvan, I.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M.
Title Operation of the ATLAS trigger system in Run 2 Type Journal Article
Year 2020 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 15 Issue 10 Pages P10004 - 59pp
Keywords Data acquisition concepts; Data reduction methods; Online farms and online filtering; Trigger concepts and systems (hardware and software)
Abstract The ATLAS experiment at the Large Hadron Collider employs a two-level trigger system to record data at an average rate of 1 kHz from physics collisions, starting from an initial bunch crossing rate of 40 MHz. During the LHC Run 2 (2015-2018), the ATLAS trigger system operated successfully with excellent performance and flexibility by adapting to the various run conditions encountered and has been vital for the ATLAS Run-2 physics programme For proton-proton running, approximately 1500 individual event selections were included in a trigger menu which specified the physics signatures and selection algorithms used for the data-taking, and the allocated event rate and bandwidth. The trigger menu must reflect the physics goals for a given data collection period, taking into account the instantaneous luminosity of the LHC and limitations from the ATLAS detector readout, online processing farm, and offline storage. This document discusses the operation of the ATLAS trigger system during the nominal proton-proton data collection in Run 2 with examples of special data-taking runs. Aspects of software validation, evolution of the trigger selection algorithms during Run 2, monitoring of the trigger system and data quality as well as trigger configuration are presented.
Address [Deliot, F.; Duvnjak, D.; Jackson, P.; Kong, A. X. Y.; Oliver, J. L.; Petridis, A.; Qureshi, A.; Sharma, A. S.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
Corporate Author Thesis
Publisher (up) 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 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000577278000004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4569
Permanent link to this record
 
 
Author ATLAS Collaboration (Aad, G. et al); Aparisi Pozo, J.A.; Bailey, A.J.; Cabrera Urban, S.; Castillo, F.L.; Castillo Gimenez, V.; Cerda Alberich, L.; Costa, M.J.; Escobar, C.; Estrada Pastor, O.; Ferrer, A.; Fiorini, L.; Fullana Torregrosa, E.; Fuster, J.; Garcia, C.; Garcia Navarro, J.E.; Gonzalez de la Hoz, S.; Gonzalvo Rodriguez, G.R.; Guerrero Rojas, J.G.R.; Higon-Rodriguez, E.; Lacasta, C.; Lozano Bahilo, J.J.; Madaffari, D.; Mamuzic, J.; Marti-Garcia, S.; Martinez Agullo, P.; Miñano, M.; Mitsou, V.A.; Moreno Llacer, M.; Poveda, J.; Rodriguez Bosca, S.; Rodriguez Rodriguez, D.; Ruiz-Martinez, A.; Salt, J.; Santra, A.; Sayago Galvan, I.; Soldevila, U.; Sanchez, J.; Valero, A.; Valls Ferrer, J.A.; Vos, M.
Title Performance of the ATLAS muon triggers in Run 2 Type Journal Article
Year 2020 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 15 Issue 9 Pages P09015 - 57pp
Keywords Data acquisition concepts; Data processing methods; Online farms and online filtering; Trigger concepts and systems (hardware and software)
Abstract The performance of the ATLAS muon trigger system is evaluated with proton-proton (pp) and heavy-ion (HI) collision data collected in Run 2 during 2015-2018 at the Large Hadron Collider. It is primarily evaluated using events containing a pair of muons from the decay of Z bosons to cover the intermediate momentum range between 26 GeV and 100 GeV. Overall, the efficiency of the single-muon triggers is about 68% in the barrel region and 85% in the endcap region. The p(T) range for efficiency determination is extended by using muons from decays of J/psi mesons, W bosons, and top quarks. The performance in HI collision data is measured and shows good agreement with the results obtained in pp collisions. The muon trigger shows uniform and stable performance in good agreement with the prediction of a detailed simulation. Dedicated multi-muon triggers with kinematic selections provide the backbone to beauty, quarkonia, and low-mass physics studies. The design, evolution and performance of these triggers are discussed in detail.
Address [Deliot, F.; Duvnjak, D.; Jackson, P.; Kong, A. X. Y.; Oliver, J. L.; Petridis, A.; Qureshi, A.; Sharma, A. S.; White, M. J.] Univ Adelaide, Dept Phys, Adelaide, SA, Australia
Corporate Author Thesis
Publisher (up) 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 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000577273400015 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4571
Permanent link to this record
 
 
Author Beltran Jimenez, J.; de Andres, D.; Delhom, A.
Title Anisotropic deformations in a class of projectively-invariant metric-affine theories of gravity Type Journal Article
Year 2020 Publication Classical and Quantum Gravity Abbreviated Journal Class. Quantum Gravity
Volume 37 Issue 22 Pages 225013 - 25pp
Keywords alternative theories of gravity; metric-affine gravity; anisotropic solutions
Abstract Among the general class of metric-affine theories of gravity, there is a special class conformed by those endowed with a projective symmetry. Perhaps the simplest manner to realise this symmetry is by constructing the action in terms of the symmetric part of the Ricci tensor. In these theories, the connection can be solved algebraically in terms of a metric that relates to the spacetime metric by means of the so-called deformation matrix that is given in terms of the matter fields. In most phenomenological applications, this deformation matrix is assumed to inherit the symmetries of the matter sector so that in the presence of an isotropic energy-momentum tensor, it respects isotropy. In this work we discuss this condition and, in particular, we show how the deformation matrix can be anisotropic even in the presence of isotropic sources due to the non-linear nature of the equations. Remarkably, we find that Eddington-inspired-Born-Infeld (EiBI) theories do not admit anisotropic deformations, but more general theories do. However, we find that the anisotropic branches of solutions are generally prone to a pathological physical behaviour.
Address [Jimenez, Jose Beltran] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: jose.beltran@usal.es;
Corporate Author Thesis
Publisher (up) 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 0264-9381 ISBN Medium
Area Expedition Conference
Notes WOS:000580878200001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4576
Permanent link to this record
 
 
Author Ahlburg, P. et al; Marinas, C.
Title EUDAQ – a data acquisition software framework for common beam telescopes Type Journal Article
Year 2020 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 15 Issue 1 Pages P01038 - 30pp
Keywords Data acquisition concepts; Detector control systems (detector and experiment monitoring and slow-control systems, architecture, hardware, algorithms, databases); Particle tracking detectors; Calorimeters
Abstract EUDAQ is a generic data acquisition software developed for use in conjunction with common beam telescopes at charged particle beam lines. Providing high-precision reference tracks for performance studies of new sensors, beam telescopes are essential for the research and development towards future detectors for high-energy physics. As beam time is a highly limited resource, EUDAQ has been designed with reliability and ease-of-use in mind. It enables flexible integration of different independent devices under test via their specific data acquisition systems into a top-level framework. EUDAQ controls all components globally, handles the data flow centrally and synchronises and records the data streams. Over the past decade, EUDAQ has been deployed as part of a wide range of successful test beam campaigns and detector development applications.
Address [Arling, J. -H.; Dreyling-Eschweiler, J.; Eichhorn, T.; Gregor, I. -M.; Irles, A.; Jansen, H.; Keller, J. S.; Kulis, S.; Lange, J.; Luetticke, F.; Perrey, H.; Peschke, R.; Pitzl, D.; Rossi, E.; Rubinsky, I.; Stanitzki, M.] Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany, Email: jan.dreyling-eschweiler@desy.de
Corporate Author Thesis
Publisher (up) 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 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000525449600038 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4649
Permanent link to this record
 
 
Author Ros Garcia, A.; Barrio, J.; Etxebeste, A.; Garcia-Lopez, J.; Jimenez-Ramos, M.C.; Lacasta, C.; Muñoz, E.; Oliver, J.F.; Roser, J.; Llosa, G.
Title MACACO II test-beam with high energy photons Type Journal Article
Year 2020 Publication Physics in Medicine and Biology Abbreviated Journal Phys. Med. Biol.
Volume 65 Issue 24 Pages 245027 - 12pp
Keywords Compton imaging; Compton camera; proton therapy; LaBr3; test-beam; image reconstruction
Abstract The IRIS group at IFIC Valencia is developing a three-layer Compton camera for treatment monitoring in proton therapy. The system is composed of three detector planes, each made of a LaBr3<i monolithic crystal coupled to a SiPM array. Having obtained successful results with the first prototype (MACACO) that demonstrated the feasibility of the proposed technology, a second prototype (MACACO II) with improved performance has been developed, and is the subject of this work. The new system has an enhanced detector energy resolution which translates into a higher spatial resolution of the telescope. The image reconstruction method has also been improved with an accurate model of the sensitivity matrix. The device has been tested with high energy photons at the National Accelerator Centre (CNA, Seville). The tests involved a proton beam of 18 MeV impinging on a graphite target, to produce 4.4 MeV photons. Data were taken at different system positions of the telescope with the first detector at 65 and 160 mm from the target, and at different beam intensities. The measurements allowed successful reconstruction of the photon emission distribution at two target positions separated by 5 mm in different telescope configurations. This result was obtained both with data recorded in the first and second telescope planes (two interaction events) and, for the first time in beam experiments, with data recorded in the three planes (three interaction events).
Address [Ros Garcia, A.; Barrio, J.; Etxebeste, A.; Lacasta, C.; Munoz, E.; Oliver, J. F.; Roser, J.; Llosa, G.] Univ Valencia, CSIC, Inst Fis Corpuscular, Valencia, Spain, Email: arosgar@ific.uv.es
Corporate Author Thesis
Publisher (up) 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 0031-9155 ISBN Medium
Area Expedition Conference
Notes WOS:000600803000001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4654
Permanent link to this record
 
 
Author Arrechea, J.; Delhom, A.; Jimenez-Cano, A.
Title Inconsistencies in four-dimensional Einstein-Gauss-Bonnet gravity Type Journal Article
Year 2021 Publication Chinese Physics C Abbreviated Journal Chin. Phys. C
Volume 45 Issue 1 Pages 013107 - 8pp
Keywords alternative theories of gravity; singularities; Einstein-Gauss-Bonnet
Abstract We attempt to clarify several aspects concerning the recently presented four-dimensional Einstein-Gauss-Bonnet gravity. We argue that the limiting procedure outlined in [Phys. Rev. Lett. 124, 081301 (2020)] generally involves ill-defined terms in the four dimensional field equations. Potential ways to circumvent this issue are discussed, alongside remarks regarding specific solutions of the theory. We prove that, although linear perturbations are well behaved around maximally symmetric backgrounds, the equations for second-order perturbations are ill-defined even around a Minkowskian background. Additionally, we perform a detailed analysis of the spherically symmetric solutions and find that the central curvature singularity can be reached within a finite proper time.
Address [Arrechea, Julio] CSIC, Inst Astrofis Andalucia, Granada, Spain, Email: arrechea@iaa.es;
Corporate Author Thesis
Publisher (up) 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 1674-1137 ISBN Medium
Area Expedition Conference
Notes WOS:000606026400001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4676
Permanent link to this record
 
 
Author Poley, L.; Stolzenberg, U.; Schwenker, B.; Frey, A.; Gottlicher, P.; Marinas, C.; Stanitzki, M.; Stelzer, B.
Title Mapping the material distribution of a complex structure in an electron beam Type Journal Article
Year 2021 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 16 Issue 1 Pages P01010 - 33pp
Keywords Detector modelling and simulations I (interaction of radiation with matter, interaction of photons with matter, interaction of hadrons with matter, etc); Particle tracking detectors; Detector design and construction technologies and materials
Abstract The simulation and analysis of High Energy Physics experiments require a realistic simulation of the detector material and its distribution. The challenge is to describe all active and passive parts of large scale detectors like ATLAS in terms of their size, position and material composition. The common method for estimating the radiation length by weighing individual components, adding up their contributions and averaging the resulting material distribution over extended structures provides a good general estimate, but can deviate significantly from the material actually present. A method has been developed to assess its material distribution with high spatial resolution using the reconstructed scattering angles and hit positions of high energy electron tracks traversing an object under investigation. The study presented here shows measurements for an extended structure with a highly inhomogeneous material distribution. The structure under investigation is an End-of-Substructure-card prototype designed for the ATLAS Inner Tracker strip tracker – a PCB populated with components of a large range of material budgets and sizes. The measurements presented here summarise requirements for data samples and reconstructed electron tracks for reliable image reconstruction of large scale, inhomogeneous samples, choices of pixel sizes compared to the size of features under investigation as well as a bremsstrahlung correction for high material densities and thicknesses.
Address [Poley, L.; Stelzer, B.] Simon Fraser Univ, Dept Phys, Univ Dr, Burnaby, BC, Canada, Email: APoley@cern.ch
Corporate Author Thesis
Publisher (up) 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 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000608273000010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4687
Permanent link to this record
 
 
Author Archidiacono, M.; Gariazzo, S.; Giunti, C.; Hannestad, S.; Tram, T.
Title Sterile neutrino self-interactions: H-0 tension and short-baseline anomalies Type Journal Article
Year 2020 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 12 Issue 12 Pages 029 - 20pp
Keywords cosmological neutrinos; cosmological parameters from CMBR; particle physics – cosmology connection; physics of the early universe
Abstract Sterile neutrinos with a mass in the eV range have been invoked as a possible explanation of a variety of short baseline (SBL) neutrino oscillation anomalies. However, if one considers neutrino oscillations between active and sterile neutrinos, such neutrinos would have been fully thermalised in the early universe, and would be therefore in strong conflict with cosmological bounds. In this study we first update cosmological bounds on the mass and energy density of eV-scale sterile neutrinos. We then perform an updated study of a previously proposed model in which the sterile neutrino couples to a new light pseudoscalar degree of freedom. Consistently with previous analyses, we find that the model provides a good fit to all cosmological data and allows the high value of H-0 measured in the local universe to be consistent with measurements of the cosmic microwave background. However, new high l polarisation data constrain the sterile neutrino mass to be less than approximately 1 eV in this scenario. Finally, we combine the cosmological bounds on the pseudoscalar model with a Bayesian inference analysis of SBL data and conclude that only a sterile mass in narrow ranges around 1 eV remains consistent with both cosmology and SBL data.
Address [Archidiacono, Maria] Univ Milan, Via G Celoria 16, I-20133 Milan, Italy, Email: maria.archidiacono@unimi.it;
Corporate Author Thesis
Publisher (up) 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 WOS:000609105900015 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4688
Permanent link to this record