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Author (down) Valcarce, A.; Vijande, J.; Richard, J.M.; Garcilazo, H. doi  openurl
  Title Stability of Heavy Tetraquarks Type Journal Article
  Year 2018 Publication Few-Body Systems Abbreviated Journal Few-Body Syst.  
  Volume 59 Issue 2 Pages 9 - 7pp  
  Keywords  
  Abstract We discuss the stability of tetraquark systems with two different masses. After some reminders about the stability of very asymmetric QQ (q) over bar(q) over bar tetraquarks, we demonstrate that in the all-heavy limit q -> Q, the system becomes unstable for standard color-additive models. We also analyze the consequences of symmetry breaking for Qq (Q) over bar(q) over bar configurations: we find a kind of metastability between the lowest threshold Q (Q) over bar + q (q) over bar and the highest one, Q (q) over bar + (Q) over barq, and we calculate the width of the resonance. Our results are consistent with the experimental observation of narrow hadrons lying well above their lowest decay threshold.  
  Address [Valcarce, A.] Univ Salamanca, Dept Fis Fundamental, E-37008 Salamanca, Spain, Email: valcarce@usal.es;  
  Corporate Author Thesis  
  Publisher Springer Wien Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0177-7963 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000427011200005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3574  
Permanent link to this record
 

 
Author (down) 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 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 (down) Vagnozzi, S.; Visinelli, L.; Mena, O.; Mota, D.F. url  doi
openurl 
  Title Do we have any hope of detecting scattering between dark energy and baryons through cosmology? Type Journal Article
  Year 2020 Publication Monthly Notices of the Royal Astronomical Society Abbreviated Journal Mon. Not. Roy. Astron. Soc.  
  Volume 493 Issue 1 Pages 1139-1152  
  Keywords cosmic background radiation; cosmological parameters; cosm logy: observations; dark energy; large-scale structure of Universe  
  Abstract We consider the possibility that dark energy and baryons might scatter off each other. The type of interaction we consider leads to a pure momentum exchange, and does not affect the background evolution of the expansion history. We parametrize this interaction in an effective way at the level of Boltzmann equations. We compute the effect of dark energy-baryon scattering on cosmological observables, focusing on the cosmic microwave background (CMB) temperature anisotropy power spectrum and the matter power spectrum. Surprisingly, we find that even huge dark energy-baryon cross-sections sigma(xb) similar to O(b), which are generically excluded by non-cosmological probes such as collider searches or precision gravity tests, only leave an insignificant imprint on the observables considered. In the case of the CMB temperature power spectrum, the only imprint consists in a sub-per cent enhancement or depletion of power (depending whether or not the dark energy equation of state lies above or below -1) at very low multipoles, which is thus swamped by cosmic variance. These effects are explained in terms of differences in how gravitational potentials decay in the presence of a dark energy-baryon scattering, which ultimately lead to an increase or decrease in the late-time integrated Sachs-Wolfe power. Even smaller related effects are imprinted on the matter power spectrum. The imprints on the CMB are not expected to be degenerate with the effects due to altering the dark energy sound speed. We conclude that, while strongly appealing, the prospects for a direct detection of dark energy through cosmology do not seem feasible when considering realistic dark energy-baryon cross-sections. As a caveat, our results hold to linear order in perturbation theory.  
  Address [Vagnozzi, Sunny] Univ Cambridge, Kat Inst Cosmol, Madingley Rd, Cambridge CB3 0HA, England, Email: sunny.vagnozzi@ast.cam.ac.uk  
  Corporate Author Thesis  
  Publisher Oxford Univ Press Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0035-8711 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000518156100081 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4320  
Permanent link to this record
 

 
Author (down) Vagnozzi, S.; Giusarma, E.; Mena, O.; Freese, K.; Gerbino, M.; Ho, S.; Lattanzi, M. url  doi
openurl 
  Title Unveiling nu secrets with cosmological data: Neutrino masses and mass hierarchy Type Journal Article
  Year 2017 Publication Physical Review D Abbreviated Journal Phys. Rev. D  
  Volume 96 Issue 12 Pages 123503 - 26pp  
  Keywords  
  Abstract Using some of the latest cosmological data sets publicly available, we derive the strongest bounds in the literature on the sum of the three active neutrino masses, M-nu, within the assumption of a background flat Lambda CDM cosmology. In the most conservative scheme, combining Planck cosmic microwave background temperature anisotropies and baryon acoustic oscillations (BAO) data, as well as the up-to-date constraint on the optical depth to reionization (tau), the tightest 95% confidence level upper bound we find is M-nu < 0.151 eV. The addition of Planck high-l polarization data, which, however, might still be contaminated by systematics, further tightens the bound to M-nu < 0.118 eV. A proper model comparison treatment shows that the two aforementioned combinations disfavor the inverted hierarchy at similar to 64% C.L. and similar to 71% C.L., respectively. In addition, we compare the constraining power of measurements of the full- shape galaxy power spectrum versus the BAO signature, from the BOSS survey. Even though the latest BOSS full-shape measurements cover a larger volume and benefit from smaller error bars compared to previous similar measurements, the analysis method commonly adopted results in their constraining power still being less powerful than that of the extracted BAO signal. Our work uses only cosmological data; imposing the constraint M-nu > 0.06 eV from oscillations data would raise the quoted upper bounds by O(0.1 sigma) and would not affect our conclusions.  
  Address [Vagnozzi, Sunny; Freese, Katherine; Gerbino, Martina] Stockholm Univ, Dept Phys, Oskar Klein Ctr Cosmoparticle Phys, SE-10691 Stockholm, Sweden, Email: sunny.vagnozzi@fysik.su.se;  
  Corporate Author Thesis  
  Publisher Amer Physical Soc Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2470-0010 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000416948100004 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 3396  
Permanent link to this record
 

 
Author (down) Vagnozzi, S.; Di Valentino, E.; Gariazzo, S.; Melchiorri, A.; Mena, O.; Silk, J. url  doi
openurl 
  Title The galaxy power spectrum take on spatial curvature and cosmic concordance Type Journal Article
  Year 2021 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe  
  Volume 33 Issue Pages 100851 - 17pp  
  Keywords Cosmological parameters; Spatial curvature; Cosmological tensions  
  Abstract The concordance of the ACDM cosmological model in light of current observations has been the subject of an intense debate in recent months. The 2018 Planck Cosmic Microwave Background (CMB) temperature anisotropy power spectrum measurements appear at face value to favour a spatially closed Universe with curvature parameter Omega(K) < 0. This preference disappears if Baryon Acoustic Oscillation (BAO) measurements are combined with Planck data to break the geometrical degeneracy, although the reliability of this combination has been questioned due to the strong tension present between the two datasets when assuming a curved Universe. Here, we approach this issue from yet another point of view, using measurements of the full-shape (FS) galaxy power spectrum, P(k), from the Baryon Oscillation Spectroscopic Survey DR12 CMASS sample. By combining Planck data with FS measurements, we break the geometrical degeneracy and find Omega(K) = 0.0023 +/- 0.0028. This constrains the Universe to be spatially flat to sub-percent precision, in excellent agreement with results obtained using BAO measurements. However, as with BAO, the overall increase in the best-fit chi(2) suggests a similar level of tension between Planck and P(k) under the assumption of a curved Universe. While the debate on spatial curvature and the concordance between cosmological datasets remains open, our results provide new perspectives on the issue, highlighting the crucial role of FS measurements in the era of precision cosmology.  
  Address [Vagnozzi, Sunny] Univ Cambridge, Kavli Inst Cosmol, Cambridge CB3 0HA, England, Email: sunny.vagnozzi@ast.cam.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 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000704383100022 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 4984  
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