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Author Babeluk, M. et al; Marinas, C.
Title (down) CMOS MAPS upgrade for the Belle II Vertex Detector Type Journal Article
Year 2023 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 1048 Issue Pages 168015 - 5pp
Keywords Belle II; VXD; SVD; PXD; VTX; Upgrade; CMOS; DMAPS
Abstract The success of the Belle II experiment in Japan relies on the very high instantaneous luminosity, close to 6x1035 cm-2 s-1, expected from the SuperKEKB collider. The corresponding beam conditions at such luminosity levels generate large rates of background particles and creates stringent constraints on the vertex detector, adding to the physics requirements. Current prospects for the occupancy rates in the present vertex detector (VXD) at full luminosity fall close to the acceptable limits and bear large uncertainties. In this context, the Belle II collaboration is considering the possibility to install an upgraded VXD system around 2027 to provide a sufficient safety margin with respect to the expected background rate and possibly enhance tracking and vertexing performance. The VTX collaboration has started the design of a fully pixelated VXD, called VTX, based on fast and highly granular Depleted Monolithic Active Pixel Sensors (DMAPS) integrated on light support structures. The two main technical features of the VTX proposal are the usage of a single sensor type over all the layers of the system and the overall material budget below 2% of radiation length, compared to the current VXD which has two different sensor technologies and about 3% of radiation length. A dedicated sensor (OBELIX), taylored to the specific needs of Belle II, is under development, evolving from the existing TJ-Monopix2 sensor. The time-stamping precision below 100 ns will allow all VTX layers to take part in the track finding strategy contrary to the current situation. The first two detection layers are designed according to a self-supported all-silicon ladder concept, where 4 contiguous sensors are diced out of a wafer, thinned and interconnected with post-processed redistribution layers. The outermost detection layers follow a more conventional approach with a cold plate and carbon fibre support structure, and light flex cables interconnecting the sensors. This document will review the context, technical details and development status of the proposed Belle II VTX.
Address [Babeluk, M.; Bergauer, T.; Irmler, C.; Schwanda, C.] Austrian Acad Sci, Inst High Energy Phys, A-1050 Vienna, Austria, Email: christian.wessel@desy.de
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:000990246200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5538
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Author Capozzi, F.; Ferreira, R.Z.; Lopez-Honorez, L.; Mena, O.
Title (down) CMB and Lyman-alpha constraints on dark matter decays to photons Type Journal Article
Year 2023 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 06 Issue 6 Pages 060 - 23pp
Keywords reionization; axions; cosmological parameters from CMBR; dark matter theory
Abstract Dark matter energy injection in the early universe modifies both the ionization history and the temperature of the intergalactic medium. In this work, we improve the CMB bounds on sub-keV dark matter and extend previous bounds from Lyman-& alpha; observations to the same mass range, resulting in new and competitive constraints on axion-like particles (ALPs) decaying into two photons. The limits depend on the underlying reionization history, here accounted self-consistently by our modified version of the publicly available DarkHistory and CLASS codes. Future measurements such as the ones from the CMB-S4 experiment may play a crucial, leading role in the search for this type of light dark matter candidates.
Address [Capozzi, Francesco] Univ Aquila, Dipartimento Sci Fis & Chim, I-67100 Laquila, Italy, Email: francesco.capozzi@univaq.it;
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:001025410500001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5584
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Author Vilella, E.; Alonso, O.; Trenado, J.; Vila, A.; Casanova, R.; Vos, M.; Garrido, L.; Dieguez, A.
Title (down) A test beam setup for the characterization of the Geiger-mode avalanche photodiode technology for particle tracking Type Journal Article
Year 2012 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A
Volume 694 Issue Pages 199-204
Keywords The Geiger-mode avalanche photodiode (GAPD); CMOS; EUDET/AIDA telescope; Schottky detector; Test beam; Trigger logic unit (TLU)
Abstract It is well known that avalanche photodiodes operated in the Geiger mode above the breakdown voltage offer a virtually infinite gain and time accuracy in the picosecond range that can be used for single photon detection. However, their performance in particle detection still remains unexplored. In this contribution, we are going to expose different steps that we have taken in order to prove the efficiency of the Geiger mode avalanche photodiodes in the aforementioned field. In particular, we will present a setup for the characterization of these sensors in a test beam. The expected results of the test beam at DESY and CERN have been simulated with Geant4 and will also be exposed.
Address [Vilella, E.; Alonso, O.; Vila, A.; Casanova, R.; Dieguez, A.] Univ Barcelona, Dept Elect, E-08028 Barcelona, Spain, Email: evilella@el.ub.es
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 0168-9002 ISBN Medium
Area Expedition Conference
Notes WOS:000311020500029 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1256
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Author Zhai, Y.J.; Giare, W.; van de Bruck, C.; Di Valentino, E.; Mena, O.; Nunes, R.C.
Title (down) A consistent view of interacting dark energy from multiple CMB probes Type Journal Article
Year 2023 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 032 - 16pp
Keywords cosmological parameters from CMBR; dark energy theory
Abstract We analyze a cosmological model featuring an interaction between dark energy and dark matter in light of the measurements of the Cosmic Microwave Background released by three independent experiments: the most recent data by the Planck satellite and the Atacama Cosmology Telescope, and WMAP (9-year data). We show that different combinations of the datasets provide similar results, always favoring an interacting dark sector with a 95% C.L. significance in the majority of the cases. Remarkably, such a preference remains consistent when cross-checked through independent probes, while always yielding a value of the expansion rate H0 consistent with the local distance ladder measurements. We investigate the source of this preference by scrutinizing the angular power spectra of temperature and polarization anisotropies as measured by different experiments.
Address [Zhai, Yuejia; Giare, William; van de Bruck, Carsten; Di Valentino, Eleonora] Univ Sheffield, Sch Math & Stat, Hounsfield Rd, Sheffield S3 7RH, England, Email: yzhai13@sheffield.ac.uk;
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:001066525900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5673
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Author Villanueva-Domingo, P.; Mena, O.; Palomares-Ruiz, S.
Title (down) A Brief Review on Primordial Black Holes as Dark Matter Type Journal Article
Year 2021 Publication Frontiers in Astronomy and Space Sciences Abbreviated Journal Front. Astron. Space Sci.
Volume 8 Issue Pages 681084 - 10pp
Keywords primordial black holes; dark matter; cosmology; accretion; 21 cm cosmology; gravitational waves; cosmic microwave background; microlensing
Abstract Primordial black holes (PBHs) represent a natural candidate for one of the components of the dark matter (DM) in the Universe. In this review, we shall discuss the basics of their formation, abundance and signatures. Some of their characteristic signals are examined, such as the emission of particles due to Hawking evaporation and the accretion of the surrounding matter, effects which could leave an impact in the evolution of the Universe and the formation of structures. The most relevant probes capable of constraining their masses and population are discussed.
Address [Villanueva-Domingo, Pablo; Mena, Olga; Palomares-Ruiz, Sergio] CSIC Univ Valencia, Inst Fis Corpuscular IFIC, Paterna, Spain, Email: pablo.villanueva.domingo@gmail.com
Corporate Author Thesis
Publisher Frontiers Media Sa Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2296-987x ISBN Medium
Area Expedition Conference
Notes WOS:000660081700001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4852
Permanent link to this record