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Author Stadler, J.; Boehm, C.; Mena, O. url  doi
openurl 
  Title Comprehensive study of neutrino-dark matter mixed damping Type Journal Article
  Year 2019 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal (down) J. Cosmol. Astropart. Phys.  
  Volume 08 Issue 8 Pages 014 - 23pp  
  Keywords CMBR theory; cosmological perturbation theory; neutrino properties; power spectrum  
  Abstract Mixed damping is a physical effect that occurs when a heavy species is coupled to a relativistic fluid which is itself free streaming. As a cross-case between collisional damping and free-streaming, it is crucial in the context of neutrino-dark matter interactions. In this work, we establish the parameter space relevant for mixed damping, and we derive an analytical approximation for the evolution of dark matter perturbations in the mixed damping regime to illustrate the physical processes responsible for the suppression of cosmological perturbations. Although extended Boltzmann codes implementing neutrino-dark matter scattering terms automatically include mixed damping, this effect has not been systematically studied. In order to obtain reliable numerical results, it is mandatory to reconsider several aspects of neutrino-dark matter interactions, such as the initial conditions, the ultra-relativistic fluid approximation and high order multiple moments in the neutrino distribution. Such a precise treatment ensures the correct assessment of the relevance of mixed damping in neutrino-dark matter interactions.  
  Address [Stadler, Julia] Univ Durham, Inst Particle Phys Phenomenol, South Rd, Durham DH1 3LE, England, Email: julia.j.stadler@durham.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:000481534700003 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4111  
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 (down) J. Cosmol. Astropart. Phys.  
  Volume 09 Issue 9 Pages 029 - 25pp  
  Keywords 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 Afonso, V.I.; Olmo, G.J.; Orazi, E.; Rubiera-Garcia, D. url  doi
openurl 
  Title New scalar compact objects in Ricci-based gravity theories Type Journal Article
  Year 2019 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal (down) J. Cosmol. Astropart. Phys.  
  Volume 12 Issue 12 Pages 044 - 20pp  
  Keywords modified gravity; gravity; GR black holes; Wormholes  
  Abstract Taking advantage of a previously developed method, which allows to map solutions of General Relativity into a broad family of theories of gravity based on the Ricci tensor (Ricci-based gravities), we find new exact analytical scalar field solutions by mapping the free-field static, spherically symmetric solution of General Relativity (GR) into quadratic f(R) gravity and the Eddington-inspired Born-Infeld gravity. The obtained solutions have some distinctive feature below the would-be Schwarzschild radius of a configuration with the same mass, though in this case no horizon is present. The compact objects found include wormholes, compact balls, shells of energy with no interior, and a new kind of object which acts as a kind of wormhole membrane. The latter object has Euclidean topology but connects antipodal points of its surface by transferring particles and null rays across its interior in virtually zero affine time. We point out the relevance of these results regarding the existence of compact scalar field objects beyond General Relativity that may effectively act as black hole mimickers.  
  Address [Afonso, Victor I.] Univ Fed Campina Grande, Unidade Acad Fis, BR-58429900 Campina Grande, PB, Brazil, Email: viafonso@df.ufcg.edu.br;  
  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:000507261900041 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4252  
Permanent link to this record
 

 
Author Blanco, C.; Escudero, M.; Hooper, D.; Witte, S.J. url  doi
openurl 
  Title Z ' mediated WIMPs: dead, dying, or soon to be detected? Type Journal Article
  Year 2019 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal (down) J. Cosmol. Astropart. Phys.  
  Volume 11 Issue 11 Pages 024 - 48pp  
  Keywords dark matter theory; dark matter detectors; dark matter experiments  
  Abstract Although weakly interacting massive particles (WIMPs) have long been among the most studied and theoretically attractive classes of candidates for the dark matter of our universe, the lack of their detection in direct detection and collider experiments has begun to dampen enthusiasm for this paradigm. In this study, we set out to appraise the status of the WIMP paradigm, focusing on the case of dark matter candidates that interact with the Standard Model through a new gauge boson. After considering a wide range of Z' mediated dark matter models, we quantitatively evaluate the fraction of the parameter space that has been excluded by existing experiments, and that is projected to fall within the reach of future direct detection experiments. Despite the existence of stringent constraints, we find that a sizable fraction of this parameter space remains viable. More specifically, if the dark matter is a Majorana fermion, we find that an order one fraction of the parameter space is in many cases untested by current experiments. Future direct detection experiments with sensitivity near the irreducible neutrino floor will be able to test a significant fraction of the currently viable parameter space, providing considerable motivation for the next generation of direct detection experiments.  
  Address [Blanco, Carlos] Univ Chicago, Dept Phys, Chicago, IL 60637 USA, Email: carlosblanco2718@uchicago.ed;  
  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:000507259700021 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4255  
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Author KM3NeT Collaboration (Aiello, S. et al); Calvo, D.; Coleiro, A.; Colomer, M.; Gozzini, S.R.; Hernandez-Rey, J.J.; Illuminati, G.; Khan Chowdhury, N.R.; Manczak, J.; Pieterse, C.; Real, D.; Thakore, T.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title KM3NeT front-end and readout electronics system: hardware, firmware, and software Type Journal Article
  Year 2019 Publication Journal of Astronomical Telescopes, Instruments and Systems Abbreviated Journal (down) J. Astron. Telesc. Instrum. Syst.  
  Volume 5 Issue 4 Pages 046001 - 15pp  
  Keywords front-end electronics; readout electronics; neutrino telescope; KM3NeT  
  Abstract The KM3NeT research infrastructure being built at the bottom of the Mediterranean Sea will host water-Cherenkov telescopes for the detection of cosmic neutrinos. The neutrino telescopes will consist of large volume three-dimensional grids of optical modules to detect the Cherenkov light from charged particles produced by neutrino-induced interactions. Each optical module houses 31 3-in. photomultiplier tubes, instrumentation for calibration of the photomultiplier signal and positioning of the optical module, and all associated electronics boards. By design, the total electrical power consumption of an optical module has been capped at seven Watts. We present an overview of the front-end and readout electronics system inside the optical module, which has been designed for a 1-ns synchronization between the clocks of all optical modules in the grid during a life time of at least 20 years. (C) 2019 Society of Photo-Optical Instrumentation Engineers (SPIE)  
  Address [Aiello, Sebastiano; Leonora, Emanuele; Longhitano, Fabio; Randazzo, Nunzio] INFN, Sez Catania, Catania, Italy, Email: v.van.beveren@nikhef.nl;  
  Corporate Author Thesis  
  Publisher Spie-Soc Photo-Optical Instrumentation Engineers Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2329-4124 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000510649500024 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4282  
Permanent link to this record
 

 
Author Bordes, J.; Hong-Mo, C.; Tsun, T.S. url  doi
openurl 
  Title Accommodating three low-scale anomalies (g-2, Lamb shift, and Atomki) in the framed Standard Model Type Journal Article
  Year 2019 Publication International Journal of Modern Physics A Abbreviated Journal (down) Int. J. Mod. Phys. A  
  Volume 34 Issue 25 Pages 1950140 - 27pp  
  Keywords Phenomenology beyond the Standard Model; lepton anomalous magnetic; moments Atomki anomaly  
  Abstract The framed Standard Model (FSM) predicts a 0(+) boson with mass around 20 MeV in the “hidden sector,” which mixes at tree level with the standard Higgs hW and hence acquires small couplings to quarks and leptons which can be calculated in the FSM apart from the mixing parameter rho Uh. The exchange of this mixed state U will contribute to g – 2 and to the Lamb shift. By adjusting rho Uh alone, it is found that the FSM can satisfy all present experimental bounds on the g – 2 and Lamb shift anomalies for μand e, and for the latter for both hydrogen and deuterium. The FSM predicts also a 1(-) boson in the “hidden sector” with a mass of 17 MeV, that is, right on top of the Atomki anomaly X. This mixes with the photon at 1-loop level and couples thereby like a dark photon to quarks and leptons. It is however a compound state and is thought likely to possess additional compound couplings to hadrons. By adjusting the mixing parameter and the X's compound coupling to nucleons, the FSM can reproduce the production rate of the X in beryllium decay as well as satisfy all the bounds on X listed so far in the literature. The above two results are consistent in that the U, being 0(+), does not contribute to the Atomki anomaly if parity and angular momentum are conserved, while X, though contributing to g – 2 and Lamb shift, has smaller couplings than U and can, at first instance, be neglected there. Thus, despite the tentative nature of the three anomalies in experiment on the one hand and of the FSM as theory on the other, the accommodation of the former in the latter has strengthened the credibility of both. Indeed, if this FSM interpretation were correct, it would change the whole aspect of the anomalies from just curiosities to windows into a vast hitherto hidden sector comprising at least in part the dark matter which makes up the bulk of our universe.  
  Address [Bordes, Jose] Univ Valencia, Ctr Mixto CSIC, Dept Fis Teor, Calle Dr Moliner 50, E-46100 Burjassot, Valencia, Spain, Email: jose.m.bordes@uv.es;  
  Corporate Author Thesis  
  Publisher World Scientific Publ Co Pte Ltd Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0217-751x ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000485680700004 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4142  
Permanent link to this record
 

 
Author Vague, J.; Melgarejo, J.C.; Boria, V.E.; Guglielmi, M.; Moreno, R.; Reglero, M.; Mata, R.; Montero, I.; Gonzalez-Iglesias, D.; Gimeno, B.; Gomez, A.; Vegas, A.; Raboso, D. doi  openurl
  Title Experimental Validation of Multipactor Effect for Ferrite Materials Used in L- and S-Band Nonreciprocal Microwave Components Type Journal Article
  Year 2019 Publication IEEE Transactions on Microwave Theory and Techniques Abbreviated Journal (down) IEEE Trans. Microw. Theory Tech.  
  Volume 67 Issue 6 Pages 2151-2161  
  Keywords Ferrites; ferromagnetic resonance; gadolinium-aluminum garnet; Holmium garnet; multipactor; space applications; wideband nonreciprocal devices  
  Abstract This paper reports on the experimental measurement of power threshold levels for the multipactor effect between samples of ferrite material typically used in the practical implementation of L-and S-band circulators and isolators. For this purposes, a new family of wideband, nonreciprocal rectangular waveguide structures loaded with ferrites has been designed with a full-wave electromagnetic simulation tool. The design also includes the required magnetostatic field biasing circuits. The multipactor breakdown power levels have also been predicted with an accurate electron tracking code using measured values for the secondary electron yield (SEY) coefficient. The measured results agree well with simulations, thereby fully validating the experimental campaign.  
  Address [Vague, Joaquin; Carlos Melgarejo, Juan; Boria, Vicente E.; Guglielmi, Marco; Reglero, Marta] Univ Politecn Valencia, iTEAM, Dept Comunicac, E-46022 Valencia, Spain, Email: jvague@dcom.upv.es;  
  Corporate Author Thesis  
  Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0018-9480 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000470969100006 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4056  
Permanent link to this record
 

 
Author Zhang, X.; Chang, C.; Gimeno, B. doi  openurl
  Title Multipactor Analysis in Circular Waveguides Excited by TM01 Mode Type Journal Article
  Year 2019 Publication IEEE Transactions on Electron Devices Abbreviated Journal (down) IEEE Trans. Electron Devices  
  Volume 66 Issue 11 Pages 4943-4951  
  Keywords Circular waveguide; multipactor; ponderomotive force; TM01 mode  
  Abstract A series of detailed numerical simulations are used to investigate the properties ofmultipactor breakdown in circularwaveguidespropagating the TM01 mode. AMonte Carlo model is constructed to track the motion of the electrons, study the multipactor scenarios, and predict the multipactor thresholds. The theoretical and numerical analyses indicate that the product of the frequency and the gap (f . D) affects both the intensity of the ponderomotive force and its spatial distribution, which results from the nonuniformity of the radio frequency (RF) field and significantly influences the electrons' trajectoriesandmultipactor trends. The decrease in f . D results in a remarkable enhancement in the magnitude of the ponderomotive force, while the maximal intensity gradually moves toward the half radius R/2 area. Low values of f . D correspond to high ponderomotive potential, which sustains the short-range electrons and triggers the single-sidedmultipactor. In contrast, high values of f . D correspond to low ponderomotive potential, contributing to long-range electrons and exciting the double-sided multipactor. Fitting to the susceptibility diagram produces the border line and a modified f . D threshold of (f . D) th approximate to 338.4 GHz mm, which separates the susceptibility diagram into single-sided, double-sided, andmixed-sided zones. The initial electron energy influences their trajectories at high f . D and low RF power. This effect tends to dominate the multipactor behavior in the mixed-sided region.  
  Address [Zhang, Xue] Xiangtan Univ, Coll Informat Engn, Xiangtan 411105, Hunan, Peoples R China, Email: zhangxue.iecas@yahoo.com;  
  Corporate Author Thesis  
  Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0018-9383 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000494419900066 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4191  
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Author Berenguer, A.; Coves, A.; Gimeno, B.; Bronchalo, E.; Boria, V.E. doi  openurl
  Title Experimental Study of the Multipactor Effect in a Partially Dielectric-Loaded Rectangular Waveguide Type Journal Article
  Year 2019 Publication IEEE Microwave and Wireless Components Letters Abbreviated Journal (down) IEEE Microw. Wirel. Compon. Lett.  
  Volume 29 Issue 9 Pages 595-597  
  Keywords Dielectric; multipactor effect; rectangular waveguide; RF breakdown; Secondary Electron Yield (SEY); waveguide transformer  
  Abstract This letter presents the experimental study of the multipactor threshold in a partially dielectric-loaded rectangular waveguide, whose results validate a multipactor model recently developed by the authors, which includes the charge distribution appearing on the dielectric surface during the multipactor discharge. First, the variation of the multipactor RF voltage threshold has been theoretically analyzed in different waveguide configurations: in an empty waveguide, and also in the cases of a one-sided and two-sided dielectric-loaded waveguides. To reach this aim, an in-house Monte Carlo simulation tool has been developed. The Secondary Electron Yield (SEY) of the metallic and dielectric materials used in the numerical simulations have been measured experimentally. Finally, an aluminum WR-75 symmetric E-plane rectangular waveguide transformer has been designed and fabricated, in which several multipaction tests have been carried out to validate the in-house software tool, demonstrating an excellent agreement between the simulation results and the experimental data.  
  Address [Berenguer, Andres; Coves, Angela; Bronchalo, Enrique] Univ Miguel Hernandez Elche, Dept Commun Engn, Elche 03202, Spain, Email: angela.coves@umh.es  
  Corporate Author Thesis  
  Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1531-1309 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000489754400009 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 4170  
Permanent link to this record
 

 
Author Albiol, F.; Corbi, A.; Albiol, A. doi  openurl
  Title Densitometric Radiographic Imaging With Contour Sensors Type Journal Article
  Year 2019 Publication IEEE Access Abbreviated Journal (down) IEEE Access  
  Volume 7 Issue Pages 18902-18914  
  Keywords Conventional X-ray imaging; contour data; densitometric images; dynamic range; depth information  
  Abstract We present the technical/physical foundations of a new imaging technique that combines ordinary radiographic information (generated by conventional X-ray settings) with the patient's volume to derive densitometric images. Traditionally, these images provide quantitative information about tissues densities. In our approach, they graphically enhance either soft or bony regions. After measuring the patient's volume with contour recognition devices, the physical traversed lengths within it (as the Roentgen beam intersects the patient) are calculated and pixel-wise associated with the original radiograph (X). In order to derive this map of lengths (L), the camera equations of the X-ray system and the contour sensor are determined. The patient's surface is also translated to the point-of-view of the X-ray beam and all its entrance/exit points are sought with the help of ray-casting methods. The derived L is applied to X as a physical operation (subtraction), obtaining soft tissue-(D-S) or bone-enhanced (D'(B)) figures. In the D-S type, the contained graphical information can be linearly mapped to the average electronic density (traversed by the X-ray beam). This feature represents an interesting proof-of-concept of associating density data to radiographs, but most important, their intensity histogram is objectively compressed, i.e., the dynamic range is more shrunk (compared against the corresponding X). This leads to other advantages: improvement in the visibility of border/edge areas (high gradient), extended manual window level/width manipulations during screening, and immediate correction of underexposed X instances. In the D-B' type, high-density elements are highlighted and easier to discern. All these results can be achieved with low-energy beam exposures, saving costs and dose. Future work will deepen this clinical side of our research. In contrast with other image-based modifiers, the proposed method is grounded on the measurement of a physical entity: the span of the X-ray beam within a body while undertaking a radiographic examination.  
  Address [Albiol, Francisco; Corbi, Alberto] CSIC, Inst Fis Corpuscular, Paterna 46980, Spain, Email: kiko@ific.uv.es  
  Corporate Author Thesis  
  Publisher Ieee-Inst Electrical Electronics Engineers Inc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2169-3536 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000459591800001 Approved no  
  Is ISI yes International Collaboration no  
  Call Number IFIC @ pastor @ Serial 3920  
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