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Author Archidiacono, M.; Gariazzo, S.; Giunti, C.; Hannestad, S.; Tram, T. url  doi
openurl 
  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 (down) 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 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
 

 
Author Reig, M.; Valle, J.W.F.; Yamada, M. url  doi
openurl 
  Title Light majoron cold dark matter from topological defects and the formation of boson stars Type Journal Article
  Year 2019 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 09 Issue 9 Pages 029 - 25pp  
  Keywords (down) Cosmic strings; domain walls; monopoles; particle physics – cosmology connection; cosmology of theories beyond the SM; cosmological neutrinos  
  Abstract We show that for a relatively light majoron (<< 100 eV) non-thermal production from topological defects is an efficient production mechanism. Taking the type I seesaw as benchmark scheme, we estimate the primordial majoron abundance and determine the required parameter choices where it can account for the observed cosmological dark matter. The latter is consistent with the scale of unification. Possible direct detection of light majorons with future experiments such as PTOLEMY and the formation of boson stars from the majoron dark matter are also discussed.  
  Address [Reig, Mario; Valle, Jose W. F.] Univ Valencia, AHEP Grp, Inst Fis Corpuscular, CSIC, Parc Cient Paterna,Catedrat Jose Beltran 2, E-46980 Paterna, Valencia, Spain, Email: mario.reig@ific.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:000487690100005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4154  
Permanent link to this record
 

 
Author Fischer, O.; Pattnaik, B.; Zurita, J. url  doi
openurl 
  Title Testing Heavy Neutral Leptons in Cosmic Ray Beam Dump experiments Type Journal Article
  Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 07 Issue 7 Pages 193 - 24pp  
  Keywords (down) Cosmic Rays; Sterile or Heavy Neutrinos; New Light Particles  
  Abstract In this work, we discuss the possibility to test Heavy Neutral Leptons (HNLs) using “Cosmic Ray Beam Dump” experiments. In analogy with terrestrial beam dump experiments, where a beam first hits a target and is then absorbed by a shield, we consider high-energy incident cosmic rays impinging on the Earth's atmosphere and then the Earth's surface. We focus here on HNL production from atmospherically produced kaon, pion and D-meson decays, and discuss the possible explanation of the appearing Cherenkov showers observed by the SHALON Cherenkov telescope and the ultra-high energy events detected by the neutrino experiment ANITA. We show that these observations can not be explained with a long-lived HNL, as the relevant parameter space is excluded by existing constraints. Then we propose two new experimental setups that are inspired by these experiments, namely a Cherenkov telescope pointing at a sub-horizontal angle and shielded by the mountain cliff at Mount Thor, and a geostationary satellite that observes part of the Sahara desert. We show that the Cherenkov telescope at Mount Thor can probe currently untested HNL parameter space for masses below the kaon mass. We also show that the geostationary satellite experiment can significantly increase the HNL parameter space coverage in the whole mass range from 10 MeV up to 2 GeV and test neutrino mixing |U-& alpha;4|(2) down to 10(-11) for masses around 300 MeV.  
  Address [Fischer, Oliver] Univ Liverpool, Dept Math Sci, Liverpool L69 3BX, England, Email: Oliver.Fischer@liverpool.ac.uk;  
  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:001037689200008 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5615  
Permanent link to this record
 

 
Author Jueid, A.; Kip, J.; Ruiz de Austri, R.; Skands, P. url  doi
openurl 
  Title The Strong Force meets the Dark Sector: a robust estimate of QCD uncertainties for anti-matter dark matter searches Type Journal Article
  Year 2024 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.  
  Volume 02 Issue 2 Pages 119 - 48pp  
  Keywords (down) Cosmic Rays; Particle Nature of Dark Matter; Specific QCD Phenomenology  
  Abstract In dark-matter annihilation channels to hadronic final states, stable particles – such as positrons, photons, antiprotons, and antineutrinos – are produced via complex sequences of phenomena including QED/QCD radiation, hadronisation, and hadron decays. These processes are normally modelled by Monte Carlo (MC) event generators whose limited accuracy imply intrinsic QCD uncertainties on the predictions for indirect-detection experiments like Fermi-LAT, Pamela, IceCube or Ams-02. In this article, we perform a comprehensive analysis of QCD uncertainties, meaning both perturbative and nonperturbative sources of uncertainty are included – estimated via variations of MC renormalization-scale and fragmentation-function parameters, respectively – in antimatter spectra from dark-matter annihilation, based on parametric variations of the Pythia 8 event generator. After performing several retunings of light-quark fragmentation functions, we define a set of variations that span a conservative estimate of the QCD uncertainties. We estimate the effects on antimatter spectra for various annihilation channels and final-state particle species, and discuss their impact on fitted values for the dark-matter mass and thermally-averaged annihilation cross section. We find dramatic impacts which can go up to O(10%) for the annihilation cross section. We provide the spectra in tabulated form including QCD uncertainties and code snippets to perform fast dark-matter fits, in this github repository.  
  Address [Jueid, Adil] Inst Basic Sci IBS, Ctr Theoret Phys Universe, Particle Theory & Cosmol Grp, Daejeon 34126, South Korea, Email: adiljueid@ibs.re.kr;  
  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:001165531600003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5956  
Permanent link to this record
 

 
Author Rodriguez-Alvarez, M.J.; Sanchez, F.; Soriano, A.; Iborra, A.; Mora, C. doi  openurl
  Title Exploiting symmetries for weight matrix design in CT imaging Type Journal Article
  Year 2011 Publication Mathematical and Computer Modelling Abbreviated Journal Math. Comput. Model.  
  Volume 54 Issue 7-8 Pages 1655-1664  
  Keywords (down) Computerized tomography imaging; Polar grid; System matrix; Rotation symmetries; ART  
  Abstract In this paper we propose several methods of constructing the system matrix (SM) of a Computed Tomography (CT) scanner with two objectives: (1) to construct SMs in the shortest possible time and store them in an ordinary PC without losing quality, (2) to analyze the possible applications of the proposed method to 3D, taking into account SMs' sizes, computing time and reconstructed image quality. In order to build the SM, we propose two new field of view (FOV) pixellation schemes, based on a polar coordinate system (polar grid) by taking advantage of the polar rotation symmetries of CT devices. Comparisons between the SMs proposed are performed using two phantom and a real CT-simulator images. Global error, contrast, noise and homogeneity of the reconstructed images are discussed.  
  Address [Rodriguez-Alvarez, MJ; Iborra, A; Mora, C] Univ Politecn Valencia, Inst Matemat Multidisciplinar, Valencia 46022, Spain, Email: mjrodri@imm.upv.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 0895-7177 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000293269200007 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ elepoucu @ Serial 708  
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Author Brook, N.H.; Castillo Garcia, L.; Conneely, T.M.; Cussans, D.; van Dijk, M.W.U.; Fohl, K.; Forty, R.; Frei, C.; Gao, R.; Gys, T.; Hancock, T.H.; Harnew, N.; Lapington, J.; Milnes, J.; Piedigrossi, D.; Rademacker, J.; Ros Garcia, A. url  doi
openurl 
  Title Testbeam studies of a TORCH prototype detector Type Journal Article
  Year 2018 Publication Nuclear Instruments & Methods in Physics Research A Abbreviated Journal Nucl. Instrum. Methods Phys. Res. A  
  Volume 908 Issue Pages 256-268  
  Keywords (down) Cherenkov radiation; Particle identification; TORCH; MCP-PMT  
  Abstract TORCH is a novel time-of-flight detector that has been developed to provide charged-particle identification between 2 and 10 GeV/c momentum. TORCH combines arrival times from multiple Cherenkov photons produced within a 10 mm-thick quartz radiator plate, to achieve a 15 ps time-of-flight resolution per incident particle. A customised Micro-Channel Plate photomultiplier tube (MCP-PMT) and associated readout system utilises an innovative charge-sharing technique between adjacent pixels to obtain the necessary 70 ps time resolution of each Cherenkov photon. A five-year R&D programme has been undertaken, culminating in the construction of a small-scale prototype TORCH module. In testbeams at CERN, this prototype operated successfully with customised electronics and readout system. A full analysis chain has been developed to reconstruct the data and to calibrate the detector. Results are compared to those using a commercial Planacon MCP-PMT, and single photon resolutions approaching 80 ps have been achieved. The photon counting efficiency was found to be in reasonable agreement with a GEANT4 Monte Carlo simulation of the detector. The small-scale demonstrator is a precursor to a full-scale TORCH module (with a radiator plate of 660 x 1250 x 10 mm(3)), which is currently under construction.  
  Address [Brook, N. H.; Cussans, D.; Garcia, A. Ros] Univ Bristol, HH Wills Phys Lab, Tyndall Ave, Bristol BS8 1TL, Avon, England, Email: mvandijk@cern.ch  
  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:000446864600033 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3760  
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. doi  openurl
  Title The Pierre Auger Observatory scaler mode for the study of solar activity modulation of galactic cosmic rays Type Journal Article
  Year 2011 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 6 Issue Pages P01003 - 16pp  
  Keywords (down) Cherenkov detectors; Large detector systems for particle and astroparticle physics; Particle detectors  
  Abstract Since data-taking began in January 2004, the Pierre Auger Observatory has been recording the count rates of low energy secondary cosmic ray particles for the self-calibration of the ground detectors of its surface detector array. After correcting for atmospheric effects, modulations of galactic cosmic rays due to solar activity and transient events are observed. Temporal variations related with the activity of the heliosphere can be determined with high accuracy due to the high total count rates. In this study, the available data are presented together with an analysis focused on the observation of Forbush decreases, where a strong correlation with neutron monitor data is found.  
  Address [Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] LIP, P-1000 Lisbon, Portugal  
  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 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000291345600003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 646  
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Author KM3NeT Collaboration (Aiello, S. et al); Barrios-Marti, J.; Calvo, D.; Coleiro, A.; Colomer, M.; Gozzini, S.R.; Hernandez-Rey, J.J.; Illuminati, G.; Khan-Chowdhury, N.R.; Lotze, M.; Perez Romero, J.; Real, D.; Thakore, T.; Zornoza, J.D.; Zuñiga, J. doi  openurl
  Title Characterisation of the Hamamatsu photomultipliers for the KM3NeT Neutrino Telescope Type Journal Article
  Year 2018 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 13 Issue Pages P05035 - 17pp  
  Keywords (down) Cherenkov detectors; Large detector systems for particle and astroparticle physics; Neutrino detectors; Photon detectors for UV, visible and IR photons (vacuum)  
  Abstract The Hamamatsu R12199-023-inch photomultiplier tube is the photodetector chosen for the first phase of the KM3NeT neutrino telescope. About 7000 photomultipliers have been characterised for dark count rate, timing spread and spurious pulses. The quantum efficiency, the gain and the peak-to-valley ratio have also been measured for a sub-sample in order to determine parameter values needed as input to numerical simulations of the detector.  
  Address [Morganti, M.] Accademia Navale Livorno, Viale Italia 72, I-57100 Livorno, Italy, Email: oleg.kalekin@physik.uni-erlangen.de;  
  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 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000433886900001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3601  
Permanent link to this record
 

 
Author KM3NeT Collaboration (Aiello, S. et al); Alves Garre, S.; Calvo, D.; Carretero, V.; Colomer, M.; Corredoira, I; Gozzini, S.R.; Hernandez-Rey, J.J.; Illuminati, G.; Khan Chowdhury, N.R.; Manczak, J.; Pieterse, C.; Real, D.; Salesa Greus, F.; Thakore, T.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title Event reconstruction for KM3NeT/ORCA using convolutional neural networks Type Journal Article
  Year 2020 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 15 Issue 10 Pages P10005 - 39pp  
  Keywords (down) Cherenkov detectors; Large detector systems for particle and astroparticle physics; Neutrino detectors; Performance of High Energy Physics Detectors  
  Abstract The KM3NeT research infrastructure is currently under construction at two locations in the Mediterranean Sea. The KM3NeT/ORCA water-Cherenkov neutrino detector off the French coast will instrument several megatons of seawater with photosensors. Its main objective is the determination of the neutrino mass ordering. This work aims at demonstrating the general applicability of deep convolutional neural networks to neutrino telescopes, using simulated datasets for the KM3NeT/ORCA detector as an example. To this end, the networks are employed to achieve reconstruction and classification tasks that constitute an alternative to the analysis pipeline presented for KM3NeT/ORCA in the KM3NeT Letter of Intent. They are used to infer event reconstruction estimates for the energy, the direction, and the interaction point of incident neutrinos. The spatial distribution of Cherenkov light generated by charged particles induced in neutrino interactions is classified as shower- or track-like, and the main background processes associated with the detection of atmospheric neutrinos are recognized. Performance comparisons to machine-learning classification and maximum-likelihood reconstruction algorithms previously developed for KM3NeT/ORCA are provided. It is shown that this application of deep convolutional neural networks to simulated datasets for a large-volume neutrino telescope yields competitive reconstruction results and performance improvements with respect to classical approaches.  
  Address [Aiello, S.; Leonora, E.; Longhitano, F.; Randazzo, N.] Ist Nazl Fis Nucl, Sez Catania, Via Santa Sofia 64, I-95123 Catania, Italy, Email: thomas.eberl@fau.de;  
  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 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000577278000005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4570  
Permanent link to this record
 

 
Author KM3NeT Collaboration (Aiello, S. et al); Alves Garre, S.; Calvo, D.; Carretero, V.; Colomer, M.; Garcia Soto, A.; Gozzini, S.R.; Hernandez-Rey, J.J.; Khan Chowdhury, N.R.; Lazo, A.; Manczak, J.; Palacios Gonzalez, J.; Pieterse, C.; Real, D.; Salesa Greus, F.; Sanchez Losa, A.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title The KM3NeT multi-PMT optical module Type Journal Article
  Year 2022 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.  
  Volume 17 Issue 7 Pages P07038 - 28pp  
  Keywords (down) Cherenkov detectors; Large detector systems for particle and astroparticle physics; Neutrino detectors  
  Abstract The optical module of the KM3NeT neutrino telescope is an innovative multi-faceted large area photodetection module. It contains 31 three-inch photomultiplier tubes in a single 0.44 m diameter pressure-resistant glass sphere. The module is a sensory device also comprising calibration instruments and electronics for power, readout and data acquisition. It is capped with a breakout-box with electronics for connection to an electro-optical cable for power and long-distance communication to the onshore control station. The design of the module was qualified for the first time in the deep sea in 2013. Since then, the technology has been further improved to meet requirements of scalability, cost-effectiveness and high reliability. The module features a sub-nanosecond timing accuracy and a dynamic range allowing the measurement of a single photon up to a cascade of thousands of photons, suited for the measurement of the Cherenkov radiation induced in water by secondary particles from interactions of neutrinos with energies in the range of GeV to PeV. A distributed production model has been implemented for the delivery of more than 6000 modules in the coming few years with an average production rate of more than 100 modules per month. In this paper a review is presented of the design of the multi-PMT KM3NeT optical module with a proven effective background suppression and signal recognition and sensitivity to the incoming direction of photons.  
  Address [Aiello, S.; Bruno, R.; Leonora, E.; Longhitano, F.; Randazzo, N.] Ist Nazl Fis Nucl, Sez Catania, Via Santa Sofia 64, I-95123 Italy, Italy, Email: km3net-pc@km3net.de  
  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 1748-0221 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000898568200003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5449  
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