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Author Ramirez, H.; Passaglia, S.; Motohashi, H.; Hu, W.; Mena, O.
Title Reconciling tensor and scalar observables in G-inflation Type Journal Article
Year 2018 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 039 - 20pp
Keywords (down) inflation; cosmological parameters from CMBR
Abstract The simple m(2)phi(2) potential as an inflationary model is coming under increasing tension with limits on the tensor-to-scalar ratio r and measurements of the scalar spectral index n(s). Cubic Galileon interactions in the context of the Horndeski action can potentially reconcile the observables. However, we show that this cannot be achieved with only a constant Galileon mass scale because the interactions turn off too slowly, leading also to gradient instabilities after inflation ends. Allowing for a more rapid transition can reconcile the observables but moderately breaks the slow-roll approximation leading to a relatively large and negative running of the tilt alpha(s) that can be of order n(s) – 1. We show that the observables on CMB and large scale structure scales can be predicted accurately using the optimized slow-roll approach instead of the traditional slow-roll expansion. Upper limits on vertical bar alpha(s)vertical bar place a lower bound of r greater than or similar to 0.005 and, conversely, a given r places a lower bound on vertical bar alpha(s)vertical bar, both of which are potentially observable with next generation CMB and large scale structure surveys.
Address [Ramirez, Hector] Univ Valencia, Dept Fis Teor, Dr Moliner 50, E-46100 Burjassot, Spain, Email: hector.ramirez@uv.es;
Corporate Author Thesis
Publisher 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:000429895200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3557
Permanent link to this record
 

 
Author Fernandez-Tejero, J. et al; Soldevila, U.
Title Humidity sensitivity of large area silicon sensors: Study and implications Type Journal Article
Year 2020 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 978 Issue Pages 164406 - 6pp
Keywords (down) Humidity sensitivity; Large area silicon sensors; Slim-edge; HL-LHC
Abstract The production of large area sensors is one of the main challenges that the ATLAS collaboration faces for the new Inner-Tracker full-silicon detector. During the prototype fabrication phase for the High Luminosity Large Hadron Collider upgrade, several ATLAS institutes observed indications of humidity sensitivity of large area sensors, even at relative humidities well below the dew point. Specifically, prototype Barrel and End-Cap silicon strip sensors fabricated in 6-inch wafers manifest a prompt decrease of the breakdown voltage when operating under high relative humidity, adversely affecting the performance of the sensors. In addition to the investigation of these prototype sensors, a specific fabrication batch with special passivation is also studied, allowing for a deeper understanding of the responsible mechanisms. This work presents an extensive study of this behaviour on large area sensors. The locations of the hotspots at the breakdown voltage at high humidity are revealed using different infrared thermography techniques. Several palliative treatments are attempted, proving the influence of sensor cleaning methods, as well as baking, on the device performance, but no improvement on the humidity sensitivity was achieved. Furthermore, a study of the incidence of the sensitivity in different batches is also presented, introducing a hypothesis of the origins of the humidity sensitivity associated to the sensor edge design, together with passivation thickness and conformity. Several actions to be taken during sensor production and assembly are extracted from this study, in order to minimize the impact of humidity sensitivity on the performance of large area silicon sensors for High Energy Physics experiments.
Address [Fernandez-Tejero, J.; Avino, O.; Fleta, C.; Ullan, M.; Vellvehi, M.] CSIC, Ctr Nacl Microelect IMB CNM, Campus UAB Bellaterra, Barcelona 08193, Spain, Email: Xavi.Fdez@cern.ch
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000560076700009 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4504
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Author Di Valentino, E.; Melchiorri, A.; Mena, O.; Vagnozzi, S.
Title Interacting dark energy in the early 2020s: A promising solution to the H-0 and cosmic shear tensions Type Journal Article
Year 2020 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe
Volume 30 Issue Pages 100666 - 12pp
Keywords (down) Hubble tension; Cosmological parameters; Dark matter; Dark energy; Interacting dark energy
Abstract We examine interactions between dark matter and dark energy in light of the latest cosmological observations, focusing on a specific model with coupling proportional to the dark energy density. Our data includes Cosmic Microwave Background (CMB) measurements from the Planck 2018 legacy data release, late-time measurements of the expansion history from Baryon Acoustic Oscillations (BAO) and Supernovae Type Ia (SNeIa), galaxy clustering and cosmic shear measurements from the Dark Energy Survey Year 1 results, and the 2019 local distance ladder measurement of the Hubble constant H-0 from the Hubble Space Telescope. Considering Planck data both in combination with BAO or SNeIa data reduces the H-0 tension to a level which could possibly be compatible with a statistical fluctuation. The very same model also significantly reduces the Omega(m) – sigma(8) tension between CMB and cosmic shear measurements. Interactions between the dark sectors of our Universe remain therefore a promising joint solution to these persisting cosmological tensions.
Address [Di Valentino, Eleonora] Univ Manchester, Jodrell Bank, Ctr Astrophys, Manchester M13 9PL, Lancs, England, Email: eleonora.divalentino@manchester.ac.uk;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2212-6864 ISBN Medium
Area Expedition Conference
Notes WOS:000595300400037 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4646
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Author Miyagawa, P.S. et al; Bernabeu, P.; Lacasta, C.; Solaz, C.; Soldevila, U.
Title Analysis of the results from Quality Control tests performed on ATLAS18 Strip Sensors during on-going production Type Journal Article
Year 2024 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 1064 Issue Pages 169457 - 9pp
Keywords (down) HL-LHC; ATLAS; ITk; Strip sensors
Abstract The ATLAS experiment will replace its existing Inner Detector with the new all -silicon Inner Tracker (ITk) to cope with the operating conditions of the forthcoming high -luminosity phase of the LHC (HL-LHC). The outer regions of the ITk will be instrumented with similar to 18000 ATLAS18 strip sensors fabricated by Hamamatsu Photonics K.K. (HPK). With the launch of full-scale sensor production in 2021, the ITk strip sensor community has undertaken quality control (QC) testing of these sensors to ensure compliance with mechanical and electrical specifications agreed with HPK. The testing is conducted at seven QC sites on each of the monthly deliveries of similar to 500 sensors. This contribution will give an overview of the QC procedures and analysis; the tests most likely to determine pass/fail for a sensor are IV, long-term leakage current stability, full strip test and visual inspection. The contribution will then present trends in the results and properties following completion of similar to 60% of production testing. It will also mention challenges overcome through collaborative efforts with HPK during the early phases of production. With less than 5% of sensors rejected by QC testing, the overall production quality has been very good.
Address [Miyagawa, P. S.; Beck, G. A.; Bevan, A. J.; Chen, Z.; Dawson, I.; Zenz, S. C.] Queen Mary Univ London, Particle Phys Res Ctr, GO Jones Bldg, Mile End Rd, London E14NS, England, Email: paul.miyagawa@cern.ch
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:001249611300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 6158
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Author Latonova, V. et al; Bernabeu, J.; Lacasta, C.; Solaz, C.; Soldevila, U.
Title Characterization of the polysilicon resistor in silicon strip sensors for ATLAS inner tracker as a function of temperature, pre- and post-irradiation Type Journal Article
Year 2023 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 1050 Issue Pages 168119 - 5pp
Keywords (down) HL-LHC; ATLAS ITk; Silicon micro-strip sensor; Polysilicon bias resistor; Testchip
Abstract The high luminosity upgrade of the Large Hadron Collider, foreseen for 2029, requires the replacement of the ATLAS Inner Detector with a new all-silicon Inner Tracker (ITk). The expected ultimate total integrated luminosity of 4000 fb(-1) means that the strip part of the ITk detector will be exposed to the total particle fluences and ionizing doses reaching the values of 1.6 center dot 10(15) MeVn(eq)/cm(2) and 0.66MGy, respectively, including a safety factor of 1.5. Radiation hard n(+)-in-p micro-strip sensors were developed by the ATLAS ITk strip collaboration and are produced by Hamamatsu Photonics K.K. The active area of each ITk strip sensor is delimited by the n-implant bias ring, which is connected to each individual n(+) implant strip by a polysilicon bias resistor. The total resistance of the polysilicon bias resistor should be within a specified range to keep all the strips at the same potential, prevent the signal discharge through the grounded bias ring and avoid the readout noise increase. While the polysilicon is a ubiquitous semiconductor material, the fluence and temperature dependence of its resistance is not easily predictable, especially for the tracking detector with the operational temperature significantly below the values typical for commercial microelectronics. Dependence of the resistance of polysilicon bias resistor on the temperature, as well as on the total delivered fluence and ionizing dose, was studied on the specially-designed test structures called ATLAS Testchips, both before and after their irradiation by protons, neutrons, and gammas to the maximal expected fluence and ionizing dose. The resistance has an atypical negative temperature dependence. It is different from silicon, which shows that the grain boundary has a significant contribution to the resistance. We discuss the contributions by parameterizing the activation energy of the polysilicon resistance as a function of the temperature for unirradiated and irradiated ATLAS Testchips.
Address [Latonova, V.; Federicova, P.; Kroll, J.; Kvasnicka, J.; Mikestikova, M.] Acad Sci Czech Republ, Inst Phys, Slovance 2, Prague 8, Czech Republic, Email: vera.latonova@cern.ch
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:001035405300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5601
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Author Becchetti, M.; Bonciani, R.; Cieri, L.; Coro, F.; Ripani, F.
Title Two-loop form factors for diphoton production in quark annihilation channel with heavy quark mass dependence Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 12 Issue 12 Pages 105 - 28pp
Keywords (down) Higher-Order Perturbative Calculations; Top Quark
Abstract We present the computation of the two-loop form factors for diphoton production in the quark annihilation channel. These quantities are relevant for the NNLO QCD corrections to diphoton production at LHC recently presented in [1]. The computation is performed retaining full dependence on the mass of the heavy quark in the loops. The master integrals are evaluated by means of differential equations which are solved exploiting the generalised power series technique.
Address [Becchetti, Matteo] Univ Torino, Dipartimento Fis, Via Pietro Giuria 1, I-10125 Turin, Italy, Email: matteo.becchetti@unito.it;
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:001130350300001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5865
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Author Alvarez, M.; Cantero, J.; Czakon, M.; Llorente, J.; Mitov, A.; Poncelet, R.
Title NNLO QCD corrections to event shapes at the LHC Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages 129 - 24pp
Keywords (down) Higher-Order Perturbative Calculations; Specific QCD Phenomenology
Abstract In this work we perform the first ever calculation of jet event shapes at hadron colliders at next-to-next-to leading order (NNLO) in QCD. The inclusion of higher order corrections removes the shape difference observed between data and next-to-leading order predictions. The theory uncertainty at NNLO is comparable to, or slightly larger than, existing measurements. Except for narrow kinematical ranges where all-order resummation becomes important, the NNLO predictions for the event shapes considered in the present work are reliable. As a prime application of the results derived in this work we provide a detailed investigation of the prospects for the precision determination of the strong coupling constant and its running through TeV scales from LHC data.
Address [Czakon, Michal] Rhein Westfal TH Aachen, Inst Theoret Teilchenphys & Kosmol, D-52056 Aachen, Germany, Email: manuel.alvarez.estevez@cern.ch;
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 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000992064600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5560
Permanent link to this record
 

 
Author Goasduff, A. et al; Gadea, A.
Title The GALILEO gamma-ray array at the Legnaro National Laboratories Type Journal Article
Year 2021 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 1015 Issue Pages 165753 - 15pp
Keywords (down) High-resolution gamma-ray spectroscopy; HPGe; Silicon; Neutron; Electronics; DAQ
Abstract GALILEO, a new 4 pi high-resolution gamma-detection array, based on HPGe detectors, has been developed and installed at the Legnaro National Laboratories. The GALILEO array greatly benefits from a fully-digital readout chain, customized DAQ, and a variety of complementary detectors to improve the resolving power by the detection of particles, ions or high-energy gamma-ray transitions. In this work, a full description of the array, including electronics and DAQ, is presented together with its complementary instrumentation.
Address [Goasduff, A.; Valiente-Dobon, J. J.; Barrientos, D.; Biasotto, M.; Brugnara, D.; Cocconi, P.; Cortes, M. L.; de Angelis, G.; Egea, F. J.; Fantinel, S.; Gambalonga, A.; Gottardo, A.; Gozzelino, A.; Gregor, E. T.; Gulmini, M.; Hadynska-Klek, K.; Illana, A.; Jaworski, G.; Napoli, D. R.; Pellumaj, J.; Perez-Vidal, R. M.; Rosso, D.; Siciliano, M.; Toniolo, N.; Volpe, V.; Zanon, I] INFN Lab Nazl Legnaro, Legnaro, Italy, Email: alain.goasduff@lnl.infn.it
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000717077900015 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5025
Permanent link to this record
 

 
Author HAWC Collaboration (Alfaro, R. et al); Salesa Greus, F.
Title Gamma/hadron separation with the HAWC observatory Type Journal Article
Year 2022 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 1039 Issue Pages 166984 - 13pp
Keywords (down) High energy; Crab Nebula; G/H separation; Machine Learning
Abstract The High Altitude Water Cherenkov (HAWC) gamma-ray observatory observes atmospheric showers produced by incident gamma rays and cosmic rays with energy from 300 GeV to more than 100 TeV. A crucial phase in analyzing gamma-ray sources using ground-based gamma-ray detectors like HAWC is to identify the showers produced by gamma rays or hadrons. The HAWC observatory records roughly 25,000 events per second, with hadrons representing the vast majority (> 99.9%) of these events. The standard gamma/hadron separation technique in HAWC uses a simple rectangular cut involving only two parameters. This work describes the implementation of more sophisticated gamma/hadron separation techniques, via machine learning methods (boosted decision trees and neural networks), and summarizes the resulting improvements in gamma/hadron separation obtained in HAWC.
Address [Alfaro, R.; Angeles Camacho, J. R.; Avila Rojas, D.; Belmont-Moreno, E.; Espinoza, C.; Garcia, D.; Hernandez, S.; Leon Vargas, H.; Sandoval, A.; Serna-Franco, J.] Univ Nacl Autonoma Mexico, Inst Fis, Mexico City, DF, Mexico, Email: tcapistran@astro.unam.mx;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000861747900006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5371
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Author Aebischer, J.; Brivio, I.; Celis, A.; Evans, J.A.; Jiang, Y.; Kumar, J.; Pan, X.Y.; Porod, W.; Rosiek, J.; Shih, D.; Staub, F.; Straub, D.M.; van Dyk, D.; Vicente, A.
Title WCxf : An exchange format for Wilson coefficients beyond the Standard Model Type Journal Article
Year 2018 Publication Computer Physics Communications Abbreviated Journal Comput. Phys. Commun.
Volume 232 Issue Pages 71-83
Keywords (down) High energy physics and computing; Models beyond the standard model
Abstract We define a data exchange format for numerical values of Wilson coefficients of local operators parameterising low-energy effects of physics beyond the Standard Model. The format facilitates interfacing model-specific Wilson coefficient calculators, renormalisation group (RG) runners, and observable calculators. It is designed to be unambiguous (defining a non-redundant set of operators with fixed normalisation in each basis), extensible (allowing the addition of new EFTs or bases by the user), and robust (being based on industry standard file formats with parsers implemented in many programming languages). We have implemented the format for the Standard Model EFT (SMEFT) and for the weak effective theory (WET) below the electroweak scale and have added interfaces to a number of public codes dealing with SMEFT or WET. We also provide command-line utilities and a Python module for convenient manipulation of WCxf files, including translation between different bases and matching from SMEFT to WET. (C) 2018 Elsevier B.V. All rights reserved.
Address [Aebischer, Jason; Pan, Xuanyou; Straub, David M.] TUM, Excellence Cluster Universe, Boltzmannstr 2, D-85748 Garching, Germany, Email: david.straub@tum.de
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0010-4655 ISBN Medium
Area Expedition Conference
Notes WOS:000442190200006 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3695
Permanent link to this record